Hensley wreck - witness account
W F Sill
For the benefit of the three or four people on the Planet who still
believe Phil Sinewe's claim that no Hensley hitch ever allowed a
trailer to sway, I find the following exact words in the account of
the witness who saw it happen and had no particular axe to grind:
". . .Traveling about 55. BRAND NEW Suburban with a older
airstream came up behind me. Slowed at first place he could pass
and let him by. He pulled back in way too close in front of me.
Missed by about 10'. Thought the usuall about his driving and watched
him catch up to the truck. Next short open spot the Sub and trailer
take off to pass. Not enough room to see oncoming traffic. Car
comes from other way over the hill, Burb cuts in front of truck,
trailer is going to hit truck, truck elects to drive thru the
sagebrush, Burb driver sees truck leaving road just as oncoming car
uses other shoulder and part of ditch to miss trailer. Burb yanks
hard left, whole rig commences to jackknife and slide down road.
Trailer brake lights come on and Burb makes sharp manuver to right.
(At this point I was braking hard and deciding which ditch to use)
Burb driver is busy cranking wheel to the left again (Why?) and
trailer brake lights go out. Burb and trailer exit road to my left at
about 40 MPH. Driver continues to make sharp left turn and
manages to roll the airstream over on its right side. I come to
serene stop just past the dust cloud. <snip> Just to let you know
the Hensley is not "Idiot Proof".
Obviously this witness agrees with me that the driver was at fault -
yet he did exactly what the Hensley literature says you can do with
impunity. This is the evidence supporting my opinion that it's
entirely possible to get a trailer swaying with ANY kind of hitch.
Even if you have one of the best-handling trailers made.
Will KD3XR ---- the Curmudgeon of Sill Hill
"Everyone is entitled to his own views. No one
is entitled to his own facts." J. Schlesinger
David Osborn
This is NOT "sway" as defined by Mr. Sill, which is "cyclic mistracking of
the towed vehicle." This was clearly driver error, with the trailer simply
following an out-of-control vehicle to the scene of the crash! No hitch,
including the Hensley Arrow, will stop a trailer from swinging around behind
the towing vehicle when the towing vehicle initiates the motion. However, this
is far different from the "cyclic mistracking of the towed vehicle" that Mr.
Sill has defined as "sway."
Following Mr. Sill's logic, I'm going to blame the Suburban's radiator cap
for not preventing this accident. It's just as reasonable to implicate the
radiator cap as it is the Hensley Arrow when the driver is the one doing doing
stupid things!
- - - - -
David, N8DO; FMCA 147762
djosborn at aol dot com
Hugh
Suburban. Besides, if you get the hitch beyond that 15 deg either way
from center, the hitch isn't supposed to act the same is it? I watched
the video again and also viewed the Pullrite video. Both use al lot of
hype. The Pullrite actually, in my opinion, uses as much or more than
Hensley. I'm beginning to believe the Hensley can actually remove most
of what we call sway. The part of the Hensley video that points this
out, is the segment where the guy tries to push on the hitch itself to
move it sideways. He can't move it, period. I'm sure, if he pushed on
the rear of the trailer part of the demo, he could skid the "trailer"
wheels. I don't like the hype but, unless the video has been speeded up,
the shots of both the Town Car and the S10 Blazer making hard turns, and
pulling back in line, demonstrate the stability of the Hensley setup.
That is a heck of a lot of trailer weight for that Blazer to handle and
it does handle it. If the Hensley can't nearly obliterate sway, the
Blazer would have been toast. There have been too many credible accounts
of owner satisfaction to keep hammering away on the sway issue. I've got
a problem with the hype and so apparently do a lot of others. Aside from
the hype, most of us agree the Hensley is a darn good hitch. I'm willing
to give Hensley the benefit of doubt and grant them their manufacturing
costs warrant the high price tag. That's not to say they couldn't cut
the price, farm out some of the work, set up some real dealerships or
make special arrangements with trailer manufacturers and get this damn
hitch into the hands of the people.
The Pullrite is also a fine hitch and it's video has more hype than
Hensley's. The segment showing a truck/trailer combo making a swerve,
with both conventional and Pullrite, while superimposing a pair of on
screen lines, is stupid. The conventional hitch segment has the driver
swerving and then the driver "saws" the wheel back and forth several
times making the trailer appear to sway. You can see this if you watch
the truck mirrors. They pop from side to side. You also can observe the
front wheels of the truck turning. In contrast, the Pullrite equipped
truck is swerved and the driver keeps the truck straight after making
the maneuver. Again the truck mirrors give it away, they stay rock
steady. Another segment is shot looking at the truck/trailer from a
frontal view. In this case, the combo is really moving at a good clip
and the driver swerves the truck left then back right. The trailer
wheels actually skid sideways and yet everything stays cool. They could
have done more in this vein and made a lot better video.
Bottom line is, each does the job, each has drawbacks and the Hensley
ought to be mandatory on all new trailers. This is my take on it, your
mileage may vary.
Hugh
Robert Carr
Please don't take this personally, but a few words in defense of the
Pullrite video.
When a trailer , that is conventionally hitched, starts oscillating
from side to side, it is very common for the tow vehicle to also
oscillate side to side. The trailer induces steering inputs to the tow
vehicle. In that case the video's demonstration of how the
conventionally hitch combination could behave is not at all
inconceivable. In fact substantial reduction of those steering inputs
is probably the primary benefit of the Pullrite system. I agree that
the mirrors confirm oscillation or swerving of the tow vehicle. Also,
if it were me performing this demo and I was in an actual
semi-controlled sway event such as this, you can bet that I would be
steering the tow vehicle, if for no other reason than to attempt some
control over the situation. Actually, I am not as sure as you that the
tow vehicles front wheels are being turned. I just now watched the
video again.
Now a second possibility. Before they show the questionable sway
event, they clearly say in the sound track"This is what could happen".
That means to me that they may have purposely made the conventionally
hitched trailer sway by see-sawing the steering of the tow vehicle to
demonstrate how the trailer might respond. When they do the same
maneuver with the Pullrite the sound track clearly states "This is
what will happen". I really don't see anything wrong with that. It is
trying to demonstrate the difference.
In the Hensley video, the guy pushes on the hitch and it doesn't move.
As far as I am concerned that particular demo illustrates that the
linkages prevent rotation at the hitch assembly. That demo was
accomplished right after showing that from the truck side, rotation
was possible. The two demo steps are an attempt to illustrate the
uni-directional property of the linkage system. That is fine, but
does nothing to illustrate that the trailer can still rotate about the
effective or virtual pivot point up near the rear axle of the tow
vehicle. We could argue that this is misleading or that it is simply a
demonstration of a particular technical fact. My point is that both of
these videos are attempts at "visual demonstration" of certain key
features. To the technical types that view these videos, various
observations, questions, etc. will naturally be raised. For some of
us, we would like a full technical report. All video recorded testing
would be accompanied by a test procedure document that would clearly
define the purpose, methods and results. Probably isn't going to
happen.
I think that the real problem with a lot of product marketing
material is that they, the marketeers, attempt to illustrate certain
key technical facts about their product. In doing so, they end up with
a number of dangling pieces of information. And yes, they use flowery
wording or puffery in the process. The problem comes about when these
dangling pieces of information are not recombined into the operation
of the whole product. For example: The uni-directional property of the
Hensley linkage system is crucial to the hitch operation. However,
that property, extrapolated too far, leads to misunderstanding the
overall operation of the hitch. In other words, the trailer is not
somehow magically locked to the tow vehicle, because the linkage
system has a uni-directional property.
I think that is enough for now
Bob
On Wed, 14 Jun 2000 00:23:50 -0400, Hugh <hug...@dreamscape.net>
wrote:
Phil Sinewe
Hugh <hug...@dreamscape.net> wrote in message
news:394708D6...@dreamscape.net...
> I've got to go with David on this one.
Me too Will, thanks for posting this account. It took three days for you to
do it, but finally a "credible report".
This is exactly what we say the hitch will do. The trailer followed the
driver. It just so happens that the driver found some reason to drive in
4x4 mode!!! In fact, it is Hensley's contention that an accident like this
could have been MUCH more severe had he not been using a Hensley. If you
read the account closely, the driver managed to miss other vehicles. This
could have been a much worse accident had the driver had less control than
he had.
The account NEVER,NEVER,NEVER mentions anything about sway. Take it or
leave it! Will, you are the one who is guilty of adding words to people's
accounts.
CASE CLOSED!
Now Will, your batting 0 % so far lets hear the account of the other
accident, we do not mind hearing accounts of how the Hensley Arrow allowed
the trailer to flawlessly follow the tow vehicle. We hate to see accidents
occur, but the hitch does not cure poor driving.
P. Sinewe
http://www.nosway.com
Robert C. Thomas
<394708D6...@dreamscape.net>...
> I've got to go with David on this one. The trailer followed the
> Suburban.
It jackknifed. This is following????
cheers
bob
Robert C. Thomas
<20000613214556...@ng-bj1.aol.com>...
> wi...@epix.net writes:
>
> Burb yanks
> >hard left, whole rig commences to jackknife and slide down road.
>
mistracking of
> the towed vehicle." This was clearly driver error, with the trailer
simply
> following an out-of-control vehicle to the scene of the crash!
Read again David. It jackknifed. This is NOT "following an out of control
vehicle to the scene of the crash. The tow was trying to pass the tow
vehicle.
Geezz,
bob
bill horne
>
> Hugh <hug...@dreamscape.net> wrote in article
> <394708D6...@dreamscape.net>...
> > Suburban.
>
>
> cheers
>
> bob
Just a small definitional problem that can be overlooked. As long as the
tongue is connected to the ball, it 'follows'. In extreme cases, it can
be said to 'follow from the front'.
--
bill
Theory don't mean squat if it don't work.
David Osborn
Bob,
The trailer was responding to steering inputs from the driver of an
out-of-control vehicle. This has *nothing* to do with trailer "sway" as it has
been defined and discussed here!
Robert Carr
events relayed by the witness. Here is another point of view based on
that sequence.
When I first read the witness accounting, I assumed that the first
hard left yank was performed by the driver steering to avoid the
truck. As I continued to think (dangerous I realize) about it and
coupled in the fact that the truck driver had already taken evasive
action, it just didn't make complete sense. So here is my take on the
situation.
The Burb turns back to the right, in front of the truck,to avoid
on-coming car. He obviously forgets that he is towing a trailer and
starts cutting into the trucks space. More or less immediately the
Burb yanks a hard left. My suspicion is that the hard left yank was
not all do to driver steering. Why on earth would he purposely perform
a hard left steer maneuver, when the truck was already leaving the
region and a car was occupying what was remaining of the
left(on-coming) lane. I believe that control had already been lost at
this time and caused most of what appeared as a "hard left yank",
which then progressed into the jackknife situation. The subsequent
right and left yanks or maneuvers are then largely a result of a
mistracking trailer, with some additional steering attempts by the
driver to regain control. In short this event could very well have
been initiated at or slightly delayed from when the Burb cut into the
trucks space. Maybe when the truck veered away from the potential side
swipe of the trailer, the event was initiated. Maybe something broke
at that time. Maybe the hitch was installed improperly. I just don't
see any obvious reason for the driver to have made a hard left
steering correction at that time, especially when he had an oncoming
car to avoid. Heck, I would much rather side-swipe a truck going my
same direction than turn into the path of an on-coming vehicle.
Needless to say, in my opinion, the trailer was mis-tracking. Whether
it was cyclic, I don't know. Looks as though it may have at least been
semi-cyclic(whatever that means).
Bob
On Wed, 14 Jun 2000 01:20:19 GMT, W F Sill <wi...@epix.net> wrote:
>
>For the benefit of the three or four people on the Planet who still
>believe Phil Sinewe's claim that no Hensley hitch ever allowed a
>trailer to sway, I find the following exact words in the account of
>the witness who saw it happen and had no particular axe to grind:
>
>". . .Traveling about 55. BRAND NEW Suburban with a older
>airstream came up behind me. Slowed at first place he could pass
>and let him by. He pulled back in way too close in front of me.
>Missed by about 10'. Thought the usuall about his driving and watched
>him catch up to the truck. Next short open spot the Sub and trailer
>take off to pass. Not enough room to see oncoming traffic. Car
>comes from other way over the hill, Burb cuts in front of truck,
>trailer is going to hit truck, truck elects to drive thru the
>sagebrush, Burb driver sees truck leaving road just as oncoming car
>uses other shoulder and part of ditch to miss trailer. Burb yanks
>hard left, whole rig commences to jackknife and slide down road.
>Trailer brake lights come on and Burb makes sharp manuver to right.
>(At this point I was braking hard and deciding which ditch to use)
>Burb driver is busy cranking wheel to the left again (Why?) and
>trailer brake lights go out. Burb and trailer exit road to my left at
>about 40 MPH. Driver continues to make sharp left turn and
>manages to roll the airstream over on its right side. I come to
>serene stop just past the dust cloud. <snip> Just to let you know
>the Hensley is not "Idiot Proof".
>
>Obviously this witness agrees with me that the driver was at fault -
>yet he did exactly what the Hensley literature says you can do with
>impunity. This is the evidence supporting my opinion that it's
>entirely possible to get a trailer swaying with ANY kind of hitch.
>Even if you have one of the best-handling trailers made.
>
Phil Sinewe
>Read again David. It jackknifed. This is NOT "following an out of control
>vehicle to the scene of the crash. The tow was trying to pass the tow
>vehicle.
Hi Bob, that is a good point. However, there is a hugh difference.
If you take a tow vehicle, and a trailer and drive it straight down the road,
say at 50 MPH. Now, suddenly turn sharp to the right or left (which was the
apparent case in this accident), as the vehicle turns, the trailer pivots and
follows the tow vehicle. If you turn hard enough, the tow vehicle turns too
tight on the trailer and the trailer jackknifes. But it does not sway or did
not sway in this case.
Or, to be much more specific, there is not evidence that there was sway in
this accident as my friend Will insist there is.
Here is another clear example. When you back a trailer up and turn way to
sharp, we all say the trailer is "jack knifed" I have never heard anyone
say, "that guy just swayed his trailer trying to get it into that parking
spot".
Hugh
are going to use my name in vain, please capitalize the first letter
<vbg>. "However, there is a hugh difference."
Hugh
Phil Sinewe wrote:
>
> In article <01bfd608$86bed900$170586cc@oemcomputer>, "Robert C. Thomas"
snipped
>
> Hi Bob, that is a good point. However, there is a hugh difference.
>
snipped
Hugh
the accident. I wonder now if the Hensley may have had some input in the
wreck. By this I mean, could the leveraging principles behind the
Hensley linkage cause steering inputs? This could partly explain the
second left turn when it would have been crazy to do so. I get the
distinct impression the driver was an arrogant idiot. His behavior was
extremely stupid and suggests to me he was a newbie to towing. Finding
himself in a real emergency situation and not knowing how to get out of
it, caused him to make some bad, bad, bad choices. I still stand by my
take on these videos, in other words, they coulda done better.
Incidentally, I also have the Equal-i-zer video and it is worse than
either of the other two. Hype is a dangerous thing if it leads to people
making bad choices while towing. Will is right to keep hammering away at
the sway issue, whether he is 100% right about his take or not. The
worst thing that can happen is for a newbie to towing thinking his hitch
setup is foolproof, resulting in an accident like described.
Hugh
"Robert Carr" <rac...@home.com> wrote in message
news:<4q3eksspafu3kpv69...@4ax.com>...
> Hugh
>
> Please don't take this personally, but a few words in defense of the
> Pullrite video.
>
snipped
Robert C. Thomas
>
> Just a small definitional problem that can be overlooked. As long as the
> tongue is connected to the ball, it 'follows'. In extreme cases, it can
> be said to 'follow from the front'.
>
> --
> bill
> Theory don't mean squat if it don't work.
>
GRIN
bob
W F Sill
after seeingh my quote of the witness report::
>This is exactly what we say the hitch will do. The trailer followed the
>driver.
Phil Sinewe is proving to be nearly as obtuse as Osborne, who has him
beat on one score because the Oz is not trying to sell anything! What
Hensley has says, in writing, is the following:
:> The force caused by slight or radical directional changes made
:> by the driver is not transferred to the trailer. The Hensley Arrow's
:> hitch box assembly prevents this from occurring.
In the incident reported, the driver's "radical directional changes"
not only whipped the trailer so far outa line that it skidded (so much
for your "straight truck" story), jacknifed, and finally rolled over -
but the Suburban towing it did not roll. Which is what anyone would
expect unless they believed the Hensley lies. Either the witness is a
deliberate liar or the hitch failed to prevent loss of control of the
trailer as advertised.
There are two possible explanations for Phile Sinewe's continued
protests on this issue, neither of them pleasant:
1) He and his bosses are so blindly ignorant of the meaning of
ordinary English sentences that they really don't understand they are
talking outa both sides of the mouths, or
2) They are the same brand of despicable liar that is so common in
marketing today.
It is simply not possible to dismiss this as a "misunderstanding" or
an "interpretation problem". The information being put out to peddle
this excellent product is clearly incorrect and deceptive, with the
result that buyers are led to believe the product will do things it
simply cannot and will not do.
W F Sill
> to be much more specific, there is not evidence that there was sway in
>this accident as my friend Will insist there is.
You are not my friend, Phil - you have forfeited that right.
There is eye-witness evidence that the trailer failed to track behind
the tow car, and that it went into uncontrolled gyrations that ended
with the trailer on it's side. The exact nature of those gyrations
was never defined, so whether there was any "cyclic" motion that you'd
call sway is a semantic issue unworthy of serious discussion.
David Osborn
>Phil Sinewe is proving to be nearly as obtuse as Osborne, who has him
>beat on one score because the Oz is not trying to sell anything!
Mr. Sill,
Please learn to spell. My name contains no "e"!
>It is simply not possible to dismiss this as a "misunderstanding" or
>an "interpretation problem". The information being put out to peddle
>this excellent product is clearly incorrect and deceptive, with the
>result that buyers are led to believe the product will do things it
>simply cannot and will not do.
Quit your griping about the Hensley advertising, unless you are going to
complain about MOST advertising. MOST advertising is deceptive in one way or
another. Two quick examples: My shirts NEVER come out as clean and as bright
as the advertising for [fill in the name here] detergent claims, and when I
drive a Pontiac I don't get any more excitement than when I drive any other GM
product, even though Pontiac claims they "build excitement"!
The question here is not, therefore, one of Hensley's advertising claims,
but rather one of whether or not the hitch actually prevents "sway" (as you
have defined it). You claim the Hensley Arrow doesn't prevent "sway" and yet
you can't provide even a single example of a case where the Hensley allowed
"cyclic mistracking of the towed behicle" (your definition of "sway."
David Osborn
>There is eye-witness evidence that the trailer failed to track behind
>the tow car, and that it went into uncontrolled gyrations that ended
>with the trailer on it's side. The exact nature of those gyrations
>was never defined, so whether there was any "cyclic" motion that you'd
>call sway is a semantic issue unworthy of serious discussion.
Mr. Sill,
A trailer that fails to track behind a wildly-weaving towing vehicle does
NOT, in any way, fit your definition of "sway." Therefore, there was -- and
remains -- no reason for you to confuse the "sway" issue with this account of a
crash clearly caused by driver error.
George Miklas
gets to 300....okay?
BTW: Phil, have you thought about the demonstration at your
place on my rig?
George
Camping page http://www.pathway.net/harmonicat/camping.htm
Got questions? Get answers over the phone at Keen.com.
Up to 100 minutes free!
http://www.keen.com
Philip Sinewe
>Not long ago, ph...@nosway.com (Phil Sinewe) wrote:
>
>> to be much more specific, there is not evidence that there was sway in
>>this accident as my friend Will insist there is.
>
>You are not my friend, Phil - you have forfeited that right.
Gee Will, I was still thinkin we were buddies {:)
Nettles
I'm just a lurker trying to learn more. Based on the example you gave
below, are we to understand the Hensley system (or the Pullrite system for
that matter) does not try to prevent a trailer to jackknife in a forward
(i.e. not backing up into a campsite) but does prevent sway.
Perhaps I am misunderstanding "jackknife". When I think of "jackknife", I
imagine the trailer trying its best at getting to the side or front of the
towing vehical (the typical "L" position).
Please, I am not trying to insult anyone, start another stupid pissing
contest, or create a new term to bitch about, I just want to educate
myself. As a disclaimer, I should note that I own a Pullrite, but I would
think that what applies to Pullrite applies to Hensley and vice versus,
thus my concern. Thanks for everyone's input!
Phil Sinewe wrote in message <3947aef1$0$25...@news.voyager.net>...
SNIP
>If you take a tow vehicle, and a trailer and drive it straight down the
road,
>say at 50 MPH. Now, suddenly turn sharp to the right or left (which was
the
>apparent case in this accident), as the vehicle turns, the trailer pivots
and
>follows the tow vehicle. If you turn hard enough, the tow vehicle turns
too
>tight on the trailer and the trailer jackknifes. But it does not sway or
did
>not sway in this case.
>
>Or, to be much more specific, there is not evidence that there was sway in
>this accident as my friend Will insist there is.
>
SNIP
Robert C. Thomas
>
> The trailer was responding to steering inputs from the driver of an
> out-of-control vehicle. This has *nothing* to do with trailer "sway" as
it has
> been defined and discussed here!
>
would have immediately been perfectly corrected back to an in line
position.
bob
Philip Sinewe
<harmonica...@pathway.net.invalid> wrote:
>Go men go! I hope that this can be settled before the thread
>gets to 300....okay?
>
>
>BTW: Phil, have you thought about the demonstration at your
>place on my rig?
George, I sent you a private E-mail.
Steph and Dud B.
I think there's an important distinction to be made here. The Hensley is
designed to help keep a trailer from getting into an out-of-control side to
side oscillation and to reduce the amount of side to side motion that is
transmitted to the tow vehicle. The jack-knife as described was initiated
by the tow vehicle. Given the situation described I'm sure a fifth-wheel
would have behaved the same way. No hitch on the market can prevent an
accident caused by reckless driving. One point is well-taken, though:
ownership of a Hensley or PullRite does not give you a license to drive like
an idiot.
--
Dudley
http://members.aol.com/stephndudb/rv.html
W F Sill <wi...@epix.net> wrote in message
news:ijmdksg55ckbr9osb...@4ax.com...
>
> For the benefit of the three or four people on the Planet who still
> believe Phil Sinewe's claim that no Hensley hitch ever allowed a
> trailer to sway, I find the following exact words in the account of
> the witness who saw it happen and had no particular axe to grind:
>
> ". . .Traveling about 55. BRAND NEW Suburban with a older
> airstream came up behind me. Slowed at first place he could pass
> and let him by. He pulled back in way too close in front of me.
> Missed by about 10'. Thought the usuall about his driving and watched
> him catch up to the truck. Next short open spot the Sub and trailer
> take off to pass. Not enough room to see oncoming traffic. Car
> comes from other way over the hill, Burb cuts in front of truck,
> trailer is going to hit truck, truck elects to drive thru the
> sagebrush, Burb driver sees truck leaving road just as oncoming car
> uses other shoulder and part of ditch to miss trailer. Burb yanks
> hard left, whole rig commences to jackknife and slide down road...
David Osborn
Not so. I never wrote anything about the Hensley correcting for foolish
driving. Any connection between the towing and towed vehicle must be designed
to allow the towed vehicle to respond to steering inputs made by the driver of
the towing vehicle, and the Hensley Arrow is no exception.
Where is the Hensley Arrow is different is in the way it allows forces
from the towed vehicle to be transferred back to the towing vehicle. Those
forces are the cause of "sway."
It only confuses the "sway"issue to introduce discussions about the towing
and towed vehicles' reactions to the driver's inapproriate steering inputs.
Bottom line: The Hensley Arrow can't prevent jacknifing; if it did, then
it wouldn't allow the combination to turn any corners!
Robert C. Thomas
<3947aef1$0$25...@news.voyager.net>...
> In article <01bfd608$86bed900$170586cc@oemcomputer>, "Robert C. Thomas"
> >Read again David. It jackknifed. This is NOT "following an out of
control
> >vehicle to the scene of the crash. The tow was trying to pass the tow
> >vehicle.
>
>
road,
> say at 50 MPH. Now, suddenly turn sharp to the right or left (which was
the
> apparent case in this accident), as the vehicle turns, the trailer pivots
and
> follows the tow vehicle. If you turn hard enough, the tow vehicle turns
too
> tight on the trailer and the trailer jackknifes.
But, why didn't the trailer immediately return to the in-line position??
But it does not sway or did
> not sway in this case.
>
> Or, to be much more specific, there is not evidence that there was sway
in
> this accident as my friend Will insist there is.
>
> Here is another clear example. When you back a trailer up and turn way
to
> sharp, we all say the trailer is "jack knifed" I have never heard anyone
> say, "that guy just swayed his trailer trying to get it into that parking
> spot".
>
There's a world of difference between backing and losing control while
going forward.
cheers
bob
>
Hugh
vise and spread grease on the floor where the trailer tires make contact
with the ground, can we then push on the rear of the trailer and make it
skid sideways in an arc? I believe we can. This would also work with the
Pullrite. We then could walk to the hitch point, both Pullrite and
Hensley, and will not be able to rock the hitch point from side to side.
This is the motion you can do with the conventional hitch, it is a
swivel point at the ball. This analogy explains the relative merits of
both hitches without complexities. This also explains why a tow vehicle
out of control, can cause a jackknife situation.
Hugh
Nettles wrote:
>
> Dear Mr. Sinewe,
> I'm just a lurker trying to learn more. Based on the example you gave
> below, are we to understand the Hensley system (or the Pullrite system for
> that matter) does not try to prevent a trailer to jackknife in a forward
> (i.e. not backing up into a campsite) but does prevent sway.
>
> Perhaps I am misunderstanding "jackknife". When I think of "jackknife", I
> imagine the trailer trying its best at getting to the side or front of the
> towing vehical (the typical "L" position).
>
> Please, I am not trying to insult anyone, start another stupid pissing
> contest, or create a new term to bitch about, I just want to educate
> myself. As a disclaimer, I should note that I own a Pullrite, but I would
> think that what applies to Pullrite applies to Hensley and vice versus,
> thus my concern. Thanks for everyone's input!
>
> Phil Sinewe wrote in message <3947aef1$0$25...@news.voyager.net>...
>
> SNIP
>
> >If you take a tow vehicle, and a trailer and drive it straight down the
> road,
> >say at 50 MPH. Now, suddenly turn sharp to the right or left (which was
> the
> >apparent case in this accident), as the vehicle turns, the trailer pivots
> and
> >follows the tow vehicle. If you turn hard enough, the tow vehicle turns
> too
> >tight on the trailer and the trailer jackknifes. But it does not sway or
> did
> >not sway in this case.
> >
> >Or, to be much more specific, there is not evidence that there was sway in
> >this accident as my friend Will insist there is.
> >
> SNIP
Philip Sinewe
>
>But, why didn't the trailer immediately return to the in-line position??
Because, It appears that the drive had lost control because he was
driving beyond the ability of any tow vehicle or trailer. No one has
said that you can not wreck a trailer with a Hensley hitch.
>There's a world of difference between backing and losing control while
>going forward.
Exactly, and a world of difference between jack knife and sway.
Philip Sinewe
>You are absolutely right. On every count. I couldn't have said it
>better, though Heaven knows I have tried - in almost the same words.
>
>A pity the Hensley people cannot communicate this story honestly.
>Instead, they make claims that the hitch WILL NOT allow unwanted
>trailer motions.
Will, I never said that the Hensley will not allow unwanted trailer
motions. I said it will not allow sway. You have a good way of
changing your statements. Now it is not sway, it is unwanted trailer
motions that you are hanging your hat.
This entire conversation is based on YOUR statement that you had two
credible reports of accidents involving sway.
I'm still waiting for you to produced the second "credible report"
W F Sill
>Will:
>I think there's an important distinction to be made here. The Hensley is
>designed to help keep a trailer from getting into an out-of-control side to
>side oscillation and to reduce the amount of side to side motion that is
>transmitted to the tow vehicle. The jack-knife as described was initiated
>by the tow vehicle. Given the situation described I'm sure a fifth-wheel
>would have behaved the same way. No hitch on the market can prevent an
>accident caused by reckless driving. One point is well-taken, though:
>ownership of a Hensley or PullRite does not give you a license to drive like
>an idiot.
You are absolutely right. On every count. I couldn't have said it
better, though Heaven knows I have tried - in almost the same words.
A pity the Hensley people cannot communicate this story honestly.
Instead, they make claims that the hitch WILL NOT allow unwanted
trailer motions.
Will KD3XR ---- the Curmudgeon of Sill Hill
Philip Sinewe
>>
>Seems like the above statement is a contradiction. Will not allow
>sway, but will allow unwanted trailer motions? How's it do that?
>Just wondering...
Hi Rich, not really a contradiction, what is being done is we lumped a
jackknife action of a tow vehicle, towing at a high rate of speed,
that was going to loose control anyway into the "sway" issue.
We have a guy who is driving totally unresponsibly. Makes a totally
dangerous passing maneuver, then has to run cars off the road, to
avoid a massive accident, and in the process, jack knifes the vehicle.
It is one of only two cases involving a Hensley hitch, and we are
calling it the final proof that a Hensley hitch allows sway to occur.
You might note that the second accident report that is "proof" has not
be provided yet.
Even Will agrees that the jackknife was initiated by the tow vehicle,
then he says that the trailer swayed. That is a contradiction in my
view.
I do not consider a jackknife under these conditions "avoidable" by
any product. Again, even Will agrees that the hitch was not at fault,
but then says that the trailer swayed. If you could show that a
trailer ended up jackknifed because the trailer swayed, that would be
a totally different issue, but it has not been shown to be the case
here.
True, it is unwanted trailer action, but the hitch likely had noting
to do with it, and in my opinion, probably gave the driver more
control than he would have had otherwise. That is my reference to
"unwanted trailer motion" Our use of unwanted trailer motion is
unwanted trailer motion in regard to sway.
Using Will's new us of the term sway, if a trailer got hit in the side
by a 747 aircraft and rolled, it would be unwanted trailer motion, and
those the trailer swayed.
W F Sill
<Ph...@nosway.com>, in a continuing attempt to be the most persistent &
obnoxious peddler on the planet, wrote:
>Will, I never said that the Hensley will not allow unwanted trailer
>motions. I said it will not allow sway. You have a good way of
>changing your statements. Now it is not sway, it is unwanted trailer
>motions that you are hanging your hat.
Either way, you lie. I avoided the use of the word sway in recent
notes about the wreck reported by a witness precisely because I
realized I was dealing with a world-class semantic nitpicker. In
fact, the witness account strongly suggests that "sway" occurred, in
this case caused by the illogical and dangerous driving. You and
your firm have persisted in telling buyers that it can't happen, and
you're lying through your clenched teeth.
>I'm still waiting for you to produced the second "credible report"
Your short & faulty memory seems to have wiped out the incident
reported in Montana where a trailer had lost it's way and wrecked
because the driver was dumb enough to tow a second trailer behind, and
did so through a windy pass. Once again, driver error was clearly
the proximate cause -- yet you and Hensley keep right on telling
people that your product "prevents" all sway, neutralizes cross winds,
acts like a straight truck, etc, ad nauseum.
Instead of heckling & nitpicking & arguing over semantics and
publicly vilifying people who point out the really bad effects of
using deceptive ads, why don't you and your boss get some help to
write HONEST descriptions of your very good product. Go ahead and
demonstrate it's good qualities with undersized tow vehicles if you
like, but QUIT implying that your hitch makes them OK for highway use
- it doesn't. As I pointed out to you years ago, a souped up garden
tractor would haul your 9600 lb Airstream down the highway -- but the
first time you encountered a frost heave on a bend (or attempted a
panic stop) that silver trailer would stuff yer little tractor into
the boonies so fast it would make yer eyes water.
------------------------
This lecture brought to you free by Will Sill KD3XR, who hopes you
are not offended by anything you read, inferred, assumed, presumed
or otherwise guessed I might have possibly meant as demeaning -
unless of course you are personally a humorless nitwit who WANTS
to be insulted. In which case be my guest.
Robert C. Thomas
> ski...@swcp.com writes:
>
> >David Osborn <djos...@aol.commnet.net> wrote in article
> ><20000614113324...@ng-bk1.aol.com>...
> >>
> >> The trailer was responding to steering inputs from the driver of
an
> >> out-of-control vehicle. This has *nothing* to do with trailer "sway"
as
> >it has
> >> been defined and discussed here!
> >>
> >Uh huh. And if the hitch performed as you seem to think, the jackknife
> >would have immediately been perfectly corrected back to an in line
> >position.
>
> Not so. I never wrote anything about the Hensley correcting for
foolish
> driving.
You said the tow followed the tow vehicle off the road. It didn't.
Any connection between the towing and towed vehicle must be designed
> to allow the towed vehicle to respond to steering inputs made by the
driver of
> the towing vehicle, and the Hensley Arrow is no exception.
And, if you think about it, there are "steering inputs" made by the tow
vehicle as a result of, for instance, a low tire, loose steering, counter
forces where an input on the tow has compressed the suspension of the tow
vehicle and reacts, etc. etc. etc.
> Where is the Hensley Arrow is different is in the way it allows
forces
> from the towed vehicle to be transferred back to the towing vehicle.
Those
> forces are the cause of "sway."
Exactly my point. No matter how "rigid" the coupling, the suspension,
tires, etc. on the tow vehicle are going to allow give and reaction. This
can cause "sway".
> It only confuses the "sway"issue to introduce discussions about the
towing
> and towed vehicles' reactions to the driver's inapproriate steering
inputs.
Oh? How about a too loose steering box? Gonna take that out of the realm
of possibility too?
> Bottom line: The Hensley Arrow can't prevent jacknifing; if it did,
then
> it wouldn't allow the combination to turn any corners!
>
Right!!! You've got it! And, if it allows the tow to go too far out in
one direction, and if the rig stays on the road, the tow will then attempt
to return to an in-line position. It will, inevitably go too far in the
other direction. I have no doubt that, given enough road, the Hensley will
do much to dampen this out. But, not instantly. Until it does, however,
the trailer is "swaying".
Capice????
bob
Robert C. Thomas
>
> A trailer that fails to track behind a wildly-weaving towing vehicle
does
> NOT, in any way, fit your definition of "sway." Therefore, there was --
and
> remains -- no reason for you to confuse the "sway" issue with this
account of a
> crash clearly caused by driver error.
>
the opposite direction........"sway"? If not, was it because the rig went
off the road before that could happen? Or, did the Hensley instantly
correct the condition, forcing the tow vehicle off the road in a straight
line???
cheers
bob
Robert C. Thomas
<3948...@wznews.webzone.net>...
>
> Perhaps I am misunderstanding "jackknife". When I think of "jackknife",
I
> imagine the trailer trying its best at getting to the side or front of
the
> towing vehical (the typical "L" position).
>
it is free to swing out in the other direction as the forces working to
straighten out the rig overcompensate. This is sway. They're both DAMN
good hitches and do more to dampen and correct sway than any others I know
of. But a too short wheeled tow vehicle, or one not adequately
suspensioned to handle the tow is still dangerous and subject to sway, as
is a driver who doesn't know, or care, what he's doing.
cheers
bob
David Osborn
>You said the tow followed the tow vehicle off the road. It didn't.
The combination went off the road together, and that off-road travel was a
direct result of inappropriate steering inputs from the driver.
>Exactly my point. No matter how "rigid" the coupling, the suspension,
>tires, etc. on the tow vehicle are going to allow give and reaction. This
>can cause "sway".
Not as has been defined on thgis newsgroup. When the towed vehicle reacts
to what the towing vehicle is doing that can be called "weaving," or "wander,"
or any number of other things, but "sway" has been defined here in a specific
manner, and that is "mistracking of the towed vehicle" or "undamper or
underdamped oscillations" or "the tail wagging the dog."
>Oh? How about a too loose steering box? Gonna take that out of the realm
>of possibility too?
See my comment just above.
>Right!!! You've got it! And, if it allows the tow to go too far out in
>one direction, and if the rig stays on the road, the tow will then attempt
>to return to an in-line position. It will, inevitably go too far in the
>other direction. I have no doubt that, given enough road, the Hensley will
>do much to dampen this out. But, not instantly. Until it does, however,
>the trailer is "swaying".
No, it isn't. It is responding to what the towing vehicle has done.
Bob, get this straight: "Sway" has a long-established definition here.
I'm not going to sit idly by and allow you to now expand the definition of
"sway" to include every possible trailer action. You may keep trying, but you
will fail.
No one, that is NO ONE, has shown even a single case of the Hensley Arrow
allowing "sway" as has been defined here. The Hensley Arrow will allow
numerous other trailer motions, but they must not, and will not, be permitted
to confuse the "sway" discussion.
David Osborn
>I dunno, David. It went out in one direction. Did it then swing out in
>the opposite direction........"sway"? If not, was it because the rig went
>off the road before that could happen? Or, did the Hensley instantly
>correct the condition, forcing the tow vehicle off the road in a straight
>line???
See my response to one of your numerous posts on this subject. "Sway" has
a specific definition here, and that definition does NOT include the trailer's
reaction to the driver of the towing vehicle making wild and inappropriate
steering inputs.
Robert Carr
I would like to interject a comment. I assume I have permission to do
so. I will apologize for being a little long, but here goes.
This entire discussion of sway, Hensley, Cyclic Mis-tracking, etc is
based largely on a failure to communicate. How is that for the
understatement of the day?
To the best of my knowledge, Will Sill first offered the definition of
sway as Cyclic Mis-tracking of a towed vehicle. In my opinion, this is
a general, all-inclusive definition. It doesn't define any other
associated unique characteristics. The towed vehicle is simply
mis-tracking the tow vehicle and is doing so in a cyclic or
oscillatory fashion. In other words, any oscillatory turning of the
trailer with respect to the tow vehicle about the hitch point fits
into the definition of cyclic mis-tracking.
Now, with that as background, David repeatedly asks Will to provide
credible evidence of an actual event involving a Hensley hitch in
which the Hensley allowed sway to occur. In other words, the Hensley
hitch allowed cyclic mis-tracking to occur. Will has offered a witness
accounting of an event. Apparently this is insufficient proof because
it requires some assumptions/conclusions to be drawn from the witness
report statements. So let's leave it at that, not totally convincing.
Now consider this. I don't believe it is necessary for Will to provide
accounting of an actual event. All he needs to do is suggest a method
by which as trailer could be forced to mis-track in a cyclic manner. I
think David is fully aware that such a method could be devised and the
method is not necessarily some unique, non-real world method. For
example one could consider a series of passing big rig trucks, lined
up like an army platoon on the move and passing to both sides of our
tow vehicle/ trailer combination. The alternate wind forces generated
by such a situation could easily cause the trailer to swing
side-to-side in a cyclic manner. In this case no single point hitch
system will ever do anything to prevent this oscillation. It, the
hitch has no leverage or control to stop such movement. To stop such
motion would require elimination of the hitch pivot.
Now let me offer a brief quote(three paragraphs) from a write-up on
controlling sway. Don't, immediately, say this is BS. Bite down on a
piece of leather and just accept what is said for the moment.
"Were it not for the tendency of many travel trailers to sway at least
occasionally, the fifth-wheel trailers may not have grown so popular.
Certainly, fifth-wheels have strong attributes. Travel trailers do
too, but the fifth-wheel does not, indeed, cannot sway".
"The travel trailers Achilles' heel is the way it's hitched to the tow
vehicle - at a point often four or five feet behind the axle. Thus,
the trailer has the necessary leverage to move the tow vehicle's rear
to one side or the other, which has the effect of steering the tow
vehicle. This steering effect can go into oscillations, which are
fondly known as fishtailing - another name for sway".
"By contrast, the fifth-wheel hitch pin is centered over the axle,
unable to move laterally, which makes the fifth wheel trailer
virtually immune to this motion".
From the above quoted paragraphs, I believe that it is quite clear
that the "sway" being addressed has an entirely different scope than
what is defined by Cyclic Mis-tracking. The sway being addressed in
the above quotes is a sub set of the more general Cyclic Mis-tracking.
It is addressing the trailer to tow vehicle steering effect only.
Nothing more is being considered. For what it is worth, I have seen
this basic definition in a number of printed articles as well as other
Web site documents. That doesn't make every thing stated in the above
quotes absolutely true, but it does define a sway cause and effect.
For the record, I am not willing to accept that a fifth wheel trailer
cannot or will not sway, anymore than a travel trailer cannot or will
not sway. Some causes and reactions affect both trailer types in the
same manner and no hitch can do anything about it. However, the travel
trailer configuration has the additional steering effect issue to
contend with, when hitched in a conventional manner. This additional
steering affect issue is, to the best of my understanding, commonly
referred to as "fishtailing".
In my opinion, when a manufacturer offers a hitch that eliminates or
virtually eliminates sway, they are addressing only the steering
effect that the trailer induces upon the tow vehicle(fishtailing). I
would like to think that most people now realize that the Hensley
hitch or Pullrite hitch really only addresses the trailer induced
steering issue. Both hitches are only relocating the pivot
point(physically or virtually)They are addressing what could be
described as a narrow component or sub-set of the more general sway
problem. The problem comes about when this is not made clear. In other
words eliminating sway and eliminating sway can mean different things,
depending on the underlying definitions. Therefore I see this problem
as a communication problem. In this case it is a failure(possibly
partial failure) of the manufacturer to provide a full description. It
is directly analogous to the claim that the hitch has a
uni-directional property, but never relate that property to the
overall hitch operation. Again, a failure to communicate.
I would be interested in David's or anyone's opinion on what I have
presented. If you think I am way of course, say so.
Bob
On 15 Jun 2000 15:43:33 GMT, djos...@aol.commnet.net (David Osborn)
wrote:
David Osborn
>I would be interested in David's or anyone's opinion on what I have
>presented. If you think I am way of course, say so.
Bob,
The RV-newsgroup accepted definition of "sway" (as defined by Mr. Sill,
yourself, and others) addresses a very real, potentially dangerous, and
rather-frequently-occurring characteristic of conventional travel trailers.
You call this characteristic "fishtailing." There is real value in maintaining
this specific definition of "sway," since it allows us to discuss the relative
merits of various hitch systems.
If, OTOH, we expand the definition of sway to include trailer motions from
a wide variety of towing-vehicle motions, we have diluted the value of any
discussion of "sway," probably to the point of it having no value at all. My
recommendation is that we keep the two issues separate, and discuss them
separately. That way, we can all know exactly what we're discussing, and we
won't have people making false claims of certain situations involving "sway"
when whatever trailer motion that existed was clearly caused by driver inputs.
For example of confusing claims of "sway," I can drive down the road weaving
back and forth between lanes and complain about my trailer having a "sway"
problem, when in fact the problem is the "loose nut" behind the steering wheel!
W F Sill
on this and related issues of the PullRite & Hensley hitch. For the
record, I'm in general if not complete agreement with the technical
stuff, and only take exception to two points:
1) The common perception that 5th-wheel setups can't/don't sway (as
Bob mentioned some sources saying) is simply a falsehood and IMO
should not be given any credence at all. Even over-the-road truckers
have experienced and reported it, and their trailers (unlike rv 5th
wheels) have vastly better balance.
2) If this were just coming up, Bob's commendably dispassionate
approach to the issue would be appropriate. But at this late date I
think Hensley management should be charged with fraud. They were made
aware more than two years ago that their ads and public statements are
misleading, confusing, and in a few cases totally false. (I have
corresponded directly with them). Their attitude is characterized by
arrogance and virtual belligerance. At one point they confirmed that
they don't give a damn about bad publicity - they consider it free
advertising!
Tolerance of misunderstandings is one thing, but I personally have
very little patience with fraud.
Robert Carr
The trouble is that I don't think there is an RV-newsgroup accepted
definition of sway. In particular, Will defines sway as cyclic
mis-tracking. It is an entirely adequate definition of the overall
sway issue. I can agree with what that includes(everything). Other
people include everything, by default, in the definition of the word
sway, ignoring or unaware of cyclic mis-tracking as a definition. The
fishtailing is one sub-component of cyclic mis-tracking. When Phil,
for example, says that his hitch will not allow sway, he should really
be talking about fishtailing component, since that is the only part
of cyclic mis-tracking that his hitch addresses. Unless we could
somehow agree that sway = fishtailing, the use of the term sway in any
discussion is too general. If we did agree that sway = fishtailing,
somebody would surely come along and want to discuss sway of a
motorhome. Now we are in trouble again. As new people enter the
newsgroup, they will not be aware of some prior agreement on what the
word sway means and might even consult the dictionary(heaven forbid).
They probably won't even know what fishtailing means for sure.
I tend to think that when someone is talking about sway, regardless of
some prior agreement, that person needs to clarify, reasonably
precisely, as to what aspect of sway he/she is referring, if required.
Otherwise it will likely include everything, by default. For example:
My hitch eliminates the sway effects caused by trailer induced
steering inputs to the tow vehicle. Of course it would be a little
better if "eliminates" was replaced with "substantially reduces".
Bob
On 15 Jun 2000 20:28:16 GMT, djos...@aol.commnet.net (David Osborn)
wrote:
snipped previous reference
>
>Bob,
> The RV-newsgroup accepted definition of "sway" (as defined by Mr. Sill,
>yourself, and others) addresses a very real, potentially dangerous, and
>rather-frequently-occurring characteristic of conventional travel trailers.
>You call this characteristic "fishtailing." There is real value in maintaining
>this specific definition of "sway," since it allows us to discuss the relative
>merits of various hitch systems.
> If, OTOH, we expand the definition of sway to include trailer motions from
>a wide variety of towing-vehicle motions, we have diluted the value of any
>discussion of "sway," probably to the point of it having no value at all. My
>recommendation is that we keep the two issues separate, and discuss them
>separately. That way, we can all know exactly what we're discussing, and we
>won't have people making false claims of certain situations involving "sway"
>when whatever trailer motion that existed was clearly caused by driver inputs.
>For example of confusing claims of "sway," I can drive down the road weaving
>back and forth between lanes and complain about my trailer having a "sway"
>problem, when in fact the problem is the "loose nut" behind the steering wheel!
>
Robert Carr
I agree with your comment on item (1), pertaining to 5th-wheel setups
or semi's for that matter. I understand your position on item (2).
Bob
David Osborn
>The trouble is that I don't think there is an RV-newsgroup accepted
>definition of sway. In particular, Will defines sway as cyclic
>mis-tracking. It is an entirely adequate definition of the overall
>sway issue. I can agree with what that includes(everything).
Bob,
There's no need to go any farther, because "cyclic mistracking" doesn't
include "everything." If a trailer weaves down the road behind someone
swinging the steering wheel side-to-side, then it's "NOT cyclic mistracking,"
since the trailer is tracking the weaving towing vehicle. I can't imagine any
reasonable person calling this "cyclic mistracking," since the trailer is still
tracking behind the weaving vehicle.
Next, take the weaving caused by the driver swinging the steering wheel to
the extreme where the trailer tires don't have sufficient grip to keep from
skidding sideways. I still can't imagine any reasonable person calling this
"cyclic mistracking," since the tires are clearly being asked to perform
outside their design envelope, and they are no longer maintaining traction.
Take the sideways-skidding trailer above one step further into a jacknife
condition because the driver slams on the brakes while the wild side-to-side
weaving is going on. I still can't imagine any reasonable person calling this
"cyclic mistracking" since it is clearly caused by the driver making totally
unreasonable steering and braking inputs, and the trailer tires simply cannot
maintain their traction under those conditions. HOWEVER, there are some on
this newsgroup who DO call this "sway," and claim that it's evidence that a
Hensley Arrow allows "sway." The logic of this conclusion escapes me, because
it's in the same category as condemning all Mercedes Benz automobiles as
grossly unsafe because one killed Princess on a city street in Paris.
I'm sorry, Bob, but I cannot accept your premise that "cyclic mistracking"
includes "everything," and I won't believe those who claim the Hensley Arrow
allows sway when all they can offer is evidence that driver error causes
crashes!
gonzo
I think you've nailed the issue down. To use David's
concept "sway as defined in this NG" which Will has stepped out
and attempted to define. Is this what the Hensley ads and Phil
speak of? Is this what the "common RV owner" speaks of?
Sway and fishtailing mean many things to many people. To some,
sway is body roll, thus to use of "anti-sway" bars to at least
minimize it. Fishtailing is pretty much self-descriptive.
I know when I first heard the term "sway" I was wondering why
body roll in trailer moving down a highway was an issue. To me,
the applied definition herein was "swerve" or "fishtailing".
And yep, I've seen it in 5th wheels...
Perhaps everyone is looking at the same word ("sway") and seeing
different things. Since I don't own a trailer, this disscussion
is merely interesting and perhaps gives me something else to
watch the other guy for. Just my $.02
Mark
mtsof...@aol.com
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Robert C. Thomas
> ski...@swcp.com writes:
>
> >You said the tow followed the tow vehicle off the road. It didn't.
>
> The combination went off the road together, and that off-road travel
was a
> direct result of inappropriate steering inputs from the driver.
>
understand.
> >Exactly my point. No matter how "rigid" the coupling, the suspension,
> >tires, etc. on the tow vehicle are going to allow give and reaction.
This
> >can cause "sway".
>
> Not as has been defined on thgis newsgroup. When the towed vehicle
reacts
> to what the towing vehicle is doing that can be called "weaving," or
"wander,"
> or any number of other things, but "sway" has been defined here in a
specific
> manner, and that is "mistracking of the towed vehicle" or "undamper or
> underdamped oscillations" or "the tail wagging the dog."
>
And the towed vehicle did react to the steering input ONCE. After that,
undampened oscillations WILL take place. In this case I don't know if the
whole shebang went off the road before that could happen. Is this so hard
to understand??
> >Oh? How about a too loose steering box? Gonna take that out of the
realm
> >of possibility too?
>
> See my comment just above.
>
> >Right!!! You've got it! And, if it allows the tow to go too far out in
> >one direction, and if the rig stays on the road, the tow will then
attempt
> >to return to an in-line position. It will, inevitably go too far in the
> >other direction. I have no doubt that, given enough road, the Hensley
will
> >do much to dampen this out. But, not instantly. Until it does,
however,
> >the trailer is "swaying".
>
> No, it isn't. It is responding to what the towing vehicle has done.
>
ONCE. Everything ELSE that happens subsequent to the input, be it
steering, wind blast, etc. is undampened oscillation...sway.
> Bob, get this straight: "Sway" has a long-established definition
here.
Actually YOU are the only one I've seen use it and that for the purpose of
trying to beat Will over the head with it. GET THIS STRAIGHT, things
happen AFTER an input, assuming the rig doesn't instantly dive off the
road. The Hensley can't prevent it.
> I'm not going to sit idly by and allow you to now expand the definition
of
> "sway" to include every possible trailer action. You may keep trying,
but you
> will fail.
You are going to sit there and allow me to anything I damn well please.
You may whine, but I will continue.
> No one, that is NO ONE, has shown even a single case of the Hensley
Arrow
> allowing "sway" as has been defined here. The Hensley Arrow will allow
> numerous other trailer motions, but they must not, and will not, be
permitted
> to confuse the "sway" discussion.
>
Yeah, you won't be confused because you think an instant slice of a dynamic
process is all there is. A pox on your house.
bob
Robert C. Thomas
> ski...@swcp.com writes:
>
> >I dunno, David. It went out in one direction. Did it then swing out in
> >the opposite direction........"sway"? If not, was it because the rig
> >off the road before that could happen? Or, did the Hensley instantly
> >correct the condition, forcing the tow vehicle off the road in a
straight
> >line???
>
> See my response to one of your numerous posts on this subject.
I did. It was as blind as most of your numerous posts.
"Sway" has
> a specific definition here, and that definition does NOT include the
trailer's
> reaction to the driver of the towing vehicle making wild and
inappropriate
> steering inputs.
It's a definition YOU like. Is it a universal constant?? I'm sorry, I'm
not going to play according to your rules. And, as I have repeatedly tried
to beat into your exceedingly dense skull, those "wild and inappropriate
steering inputs" cause the tow to react ONCE. THEN, the tow reacts in the
opposite direction, NOT in response to steering inputs but in reaction to
those forces that try to make a tow follow a tow vehicle. This will not
happen in one sharp correction to exactly the correct point. Please stop
your constant repetition of the same tired line that totally ignores the
law of physics AFTER the initial tow diversion from "in-line" Try, for
once in your life, to look at the WHOLE picture, instead of that little bit
that allows you to claim you're "RIGHT"
bob
David Osborn
>Bob,
>I think you've nailed the issue down. To use David's
>concept "sway as defined in this NG" which Will has stepped out
>and attempted to define. Is this what the Hensley ads and Phil
>speak of? Is this what the "common RV owner" speaks of?
>
>Sway and fishtailing mean many things to many people. To some,
>sway is body roll, thus to use of "anti-sway" bars to at least
>minimize it. Fishtailing is pretty much self-descriptive.
>
>I know when I first heard the term "sway" I was wondering why
>body roll in trailer moving down a highway was an issue. To me,
>the applied definition herein was "swerve" or "fishtailing".
>And yep, I've seen it in 5th wheels...
>
>Perhaps everyone is looking at the same word ("sway") and seeing
>different things. Since I don't own a trailer, this disscussion
>is merely interesting and perhaps gives me something else to
>watch the other guy for. Just my $.02
Mark,
Probably the best definition for "sway" was given by someone who described
it as "undamped or underdamped positive-feedback oscillation of the towed
vehicle." While that may be less-than-meaningful to some, it gives an
excellent description of what is happening when a trailer sways going down the
road.
BTW, I've never seen a semi-trailer experiencing that type of oscillation.
I've seen full semi-trailer/full trailer combinations (doubles and triples)
experiencing it, but that's not surprising considering the dolly arrangement
they use. (Anyone who's familiar with four-wheel farm wagons knows they have a
most interesting "wiggle" while going down the road, particularly if there is a
combination "train" of more than one!)
David Osborn
>"Sway" has
>> a specific definition here, and that definition does NOT include the
>trailer's
>> reaction to the driver of the towing vehicle making wild and
>inappropriate
>> steering inputs.
>It's a definition YOU like. Is it a universal constant??
It's Mr. Sill's definition. It's been good enough that no one, including
you, has claimed that it's wrong. If you wish to argue with Mr. Sill's
definition, then take it up with him.
>I'm sorry, I'm
>not going to play according to your rules.
Then go away. You add nothing useful to the discussion of sway when you
include the trailer's reaction to a crazy driver.
>And, as I have repeatedly tried
>to beat into your exceedingly dense skull, those "wild and inappropriate
>steering inputs" cause the tow to react ONCE. THEN, the tow reacts in the
>opposite direction, NOT in response to steering inputs but in reaction to
>those forces that try to make a tow follow a tow vehicle.
That is still not the "sway" that trailerists are concerned about. They
are concerned when they go sraight down the road and the combination begins to
act as if it has a "mind of it's own. That's the "mistracking" Mr. Sill has
written about. A better term is undamped or underdamped positive-feedback
oscillation. That's an ENTIRELY different scenerio from the one you keep
discussing.
>This will not
>happen in one sharp correction to exactly the correct point.
I never said that it would.
>Please stop
>your constant repetition of the same tired line that totally ignores the
>law of physics AFTER the initial tow diversion from "in-line"
I will continue the same repetition as long as we're discussing "sway."
If you wish to discuss the physics of the towed vehicle reaponding to wild
excursions of the towing vehicle then I'll be happy to do that. However, I
will NOT pollute the "sway" discussion with that one!
>Try, for
>once in your life, to look at the WHOLE picture, instead of that little bit
>that allows you to claim you're "RIGHT"
I have been looking at the "WHOLE" picture. I'm simply calling that
picture what it is, instead of claiming that it's something it isn't, as you
are!
Robert Carr
When I said that cyclic mis-tracking included everything, I was not
thinking about driver inputs at that time. I was only considering
other sway causes/effects that no hitch could prevent. Specifically
other sway forms that are not included within the definition of
fishtailing. However, now that you brought it up, it needs to be dealt
with in some manner.
My first thought, about 1 milli-second after reading your comment, was
to exclude driver inputs. However, that is not a proper approach. For
example: The so-called fishtailing form of sway is created through the
steering inputs from the trailer to the tow vehicle. One of the
biggest problems with this form of sway is that the driver will most
likely attempt corrective steering actions. In some cases the driver
will also use the brakes. I suppose in some cases the driver may help
the situation, but often the driver further amplifies the sway. It is
just the nature of what is going on and the instinctive nature of a
driver to attempt saving his rig and himself. This facet of
fishtailing is, in my opinion, why this particular form of sway is so
dangerous.
In reference to a driver weaving down the road, with the trailer
following. I suppose I could nit pick this one and say that if the
driver is purposely following a sine wave type pattern while
proceeding down the road, he is causing cyclic mis-tracking. The
trailer will not track the tow vehicle and will in general track to
the inside of the tow vehicle. The polarity of the mis-tracking will
be left/right turn dependent and therefore cyclic in nature. I don't
think this is what either of us, or anyone else, is interested in
discussing. So let's just forget about this particular possibility. I
would only add that this sort of driving may very well initiate a sway
event, if the tow vehicle/trailer rig is improperly set-up,
particularly with a conventional hitch.
In reference to the driver violently turning the tow vehicle, such
that the trailer tires adhesion has long been lost. Actually this is
an extension of the previous paragraph, with the key difference being
that something is over-driving the rig. Of course this so-called
over-driving of the rig could be initiated as a part of accident
avoidance, an avoidance situation not created by this driver. This
would be different than the witness account for the Hensley Wreck, in
which the driver of the Suburban/trailer did a lot of dumb things,
although accident avoidance became an issue. Unfortunately, it could
also be an extension of fishtailing, which as described earlier,
usually get's the driver involved with possible radical steering
attempts.
I think the key point in addressing violent steering inputs by the
driver is to realize that no hitch can guarantee the outcome. Some
will do better than others. It becomes a matter of degree. At some
point the tow vehicle/trailer combination becomes a wreck. Discussion
of sway, fishtailing, cyclic mis-tracking becomes moot point. In this
recent report, one cannot very well claim that the rig in a jackknife
configuration sliding down the road was cyclic mis-tracking. It was
mis-tracking, but not cyclic. After that, the rig was apparently
changing direction in some form. The cause may have been solely the
driver, possibly the trailer was dictating direction and more likely a
combination of the two inputs. As I understood this particular event,
following the jackknife slide, we got one right yank followed by one
left yank and that was all she wrote. Not much of a cyclic phenomena.
Again, the key point is to realize that no single point(pivot) hitch
system can flat dictate what the trailer will do. In this situation,
the tow vehicle was not in control.
I reserve the right to change my opinions on this particular part of
the discussion. I am offering my initial opinions, so that we may
proceed.
Bob
On 15 Jun 2000 22:03:04 GMT, djos...@aol.commnet.net (David Osborn)
wrote:
>rac...@home.com writes (in part):
David Osborn
>In reference to the driver violently turning the tow vehicle, such
>that the trailer tires adhesion has long been lost. Actually this is
>an extension of the previous paragraph, with the key difference being
>that something is over-driving the rig. Of course this so-called
>over-driving of the rig could be initiated as a part of accident
>avoidance, an avoidance situation not created by this driver. This
>would be different than the witness account for the Hensley Wreck, in
>which the driver of the Suburban/trailer did a lot of dumb things,
>although accident avoidance became an issue.
It is not at all clear that "this would be different." We have one
account of the accident, and if you are at all familiar with accident
investigation, you are well aware that the details of single eyewitness account
can be quite close to what actually happened, or they can be quite far removed.
You are also undoubtedly aware that different eyewitness accounts of the same
incident can vary so widely that one sometimes wonders if they saw the same
incident. Therefore, we can't possibly (without much additional scientific
investigation that we don't have available to us) know exactly what happened
and in what sequence. We can only know that the driver made grossly
inappropriate steering inputs that resulted in a crash during which a jacknife
occurred.
>I think the key point in addressing violent steering inputs by the
>driver is to realize that no hitch can guarantee the outcome. Some
>will do better than others. It becomes a matter of degree. At some
>point the tow vehicle/trailer combination becomes a wreck. Discussion
>of sway, fishtailing, cyclic mis-tracking becomes moot point. In this
>recent report, one cannot very well claim that the rig in a jackknife
>configuration sliding down the road was cyclic mis-tracking. It was
>mis-tracking, but not cyclic. After that, the rig was apparently
>changing direction in some form. The cause may have been solely the
>driver, possibly the trailer was dictating direction and more likely a
>combination of the two inputs. As I understood this particular event,
>following the jackknife slide, we got one right yank followed by one
>left yank and that was all she wrote. Not much of a cyclic phenomena.
>Again, the key point is to realize that no single point(pivot) hitch
>system can flat dictate what the trailer will do. In this situation,
>the tow vehicle was not in control.
When the towing vehicle is out of control, all bets are off, and any
discussion of "sway" is meaningless. That's why I have consistently objected
to this crash being used in any way to make any statements of any kind
regarding the performance of the Hensley Arrow. There are so many questions
that cannot possibly be answered that the discussion is at best a waste of
time, and at worst an unfair indictment of a fine product.
>I reserve the right to change my opinions on this particular part of
>the discussion. I am offering my initial opinions, so that we may
>proceed.
I appreciate the way you approach this, and other, discussions. Thanks!
Robert Carr
Sorry, pushed wrong button and sent you email.
Now have correct button
That description(UPFO) does describe, in a reasonable fashion, what is
happening, but again too general. It does not directly relate,
without further comment, that we are describing trailer induced
steering inputs to the tow vehicle. By not clarifying that point,
discussion of what a fifth wheel, Pullrite or Hensley hitch addresses
becomes confusing. I am not hung-up on calling it fishtailing at all.
That's a term used in various RV literature and of course requires
it's own definition. I would much rather see a person just lay out on
the line, what he/she is talking about. If it is trailer induced
steering inputs, then say so in the discussion. That way there is no
confusion and all readers can at least start with the same foundation.
Bob
On 15 Jun 2000 23:13:11 GMT, djos...@aol.commnet.net (David Osborn)
wrote:
snipped previous reference
>
>Mark,
> Probably the best definition for "sway" was given by someone who described
>it as "undamped or underdamped positive-feedback oscillation of the towed
>vehicle." While that may be less-than-meaningful to some, it gives an
>excellent description of what is happening when a trailer sways going down the
>road.
> BTW, I've never seen a semi-trailer experiencing that type of oscillation.
> I've seen full semi-trailer/full trailer combinations (doubles and triples)
>experiencing it, but that's not surprising considering the dolly arrangement
>they use. (Anyone who's familiar with four-wheel farm wagons knows they have a
>most interesting "wiggle" while going down the road, particularly if there is a
>combination "train" of more than one!)
>
>
David Osborn
>rac...@home.com writes (in part):
>
>>In reference to the driver violently turning the tow vehicle, such
>>that the trailer tires adhesion has long been lost. Actually this is
>>an extension of the previous paragraph, with the key difference being
>>that something is over-driving the rig. Of course this so-called
>>over-driving of the rig could be initiated as a part of accident
>>avoidance, an avoidance situation not created by this driver. This
>>would be different than the witness account for the Hensley Wreck, in
>>which the driver of the Suburban/trailer did a lot of dumb things,
>>although accident avoidance became an issue.
>
> It is not at all clear that "this would be different."
PLEASE DELETE THE ABOVE COMMENT. IT SOULD NOT BE IN THIS POST
David Osborn
>That description(UPFO) does describe, in a reasonable fashion, what is
>happening, but again too general. It does not directly relate,
>without further comment, that we are describing trailer induced
>steering inputs to the tow vehicle. By not clarifying that point,
>discussion of what a fifth wheel, Pullrite or Hensley hitch addresses
>becomes confusing. I am not hung-up on calling it fishtailing at all.
>That's a term used in various RV literature and of course requires
>it's own definition. I would much rather see a person just lay out on
>the line, what he/she is talking about. If it is trailer induced
>steering inputs, then say so in the discussion. That way there is no
>confusion and all readers can at least start with the same foundation.
Bob,
I would be quite happy if all of the discussions here started with the a
common foundation that eliminated confusion. I anxiously await the day that
occurs. (Pleas note, however, that I'm not holding my breath!)
Ralph Lindberg & Ellen Winnie
<wi...@epix.net> wrote:
>
> 1) The common perception that 5th-wheel setups can't/don't sway (as
> Bob mentioned some sources saying) is simply a falsehood and IMO
> should not be given any credence at all. Even over-the-road truckers
> have experienced and reported it, and their trailers (unlike rv 5th
> wheels) have vastly better balance.
I've had a slight sway problem under extreme conditions. Like
cross-winds with approaching semi's. Not bad, but I have felt the
trailer move.
--
Ralph Lindberg personal email n7...@amsat.org
RV and Camping FAQ http://kendaco.telebyte.com/rlindber/rv
If Windows is the answer I would really like to know what the question is
David Osborn
>In article <hjgiksc0rbr0t5ia3...@4ax.com>, W F Sill
><wi...@epix.net> wrote:
>
>
>>
>> 1) The common perception that 5th-wheel setups can't/don't sway (as
>> Bob mentioned some sources saying) is simply a falsehood and IMO
>> should not be given any credence at all. Even over-the-road truckers
>> have experienced and reported it, and their trailers (unlike rv 5th
>> wheels) have vastly better balance.
>
> I've had a slight sway problem under extreme conditions. Like
>cross-winds with approaching semi's. Not bad, but I have felt the
>trailer move.
The real problem here is that things are being called "sway" even though
they don't fit the RV-newsgroup definition of "sway"!
Remember, "sway" is an undamped or underdamped oscillation, or a cyclic
mistracking, of the trailer. A gust of wind from a passing semi (or from
whatever source) may move the trailer, but if the trailer promptly returns to
the proper position, then it isn't sway! There needs to be a sustained
oscillation, such as numerous conventionally-hitched trailers exhibit, to fit
the RV newsgroup definition.
If we allow *any* trailer motion to qualify as "sway," then the term
becomes totally meaningless, since even turning a corner would qualify as
"sway"!
bill horne
>
> rlin...@kendaco.telebyte.com writes:
>
> >In article <hjgiksc0rbr0t5ia3...@4ax.com>, W F Sill
> ><wi...@epix.net> wrote:
> >
> >
> >>
> >> 1) The common perception that 5th-wheel setups can't/don't sway (as
> >> Bob mentioned some sources saying) is simply a falsehood and IMO
> >> should not be given any credence at all. Even over-the-road truckers
> >> have experienced and reported it, and their trailers (unlike rv 5th
> >> wheels) have vastly better balance.
> >
> > I've had a slight sway problem under extreme conditions. Like
> >cross-winds with approaching semi's. Not bad, but I have felt the
> >trailer move.
>
> The real problem here is that things are being called "sway" even though
> they don't fit the RV-newsgroup definition of "sway"!
> Remember, "sway" is an undamped or underdamped oscillation, or a cyclic
> mistracking, of the trailer. A gust of wind from a passing semi (or from
> whatever source) may move the trailer, but if the trailer promptly returns to
> the proper position, then it isn't sway!
It is, in fact, the beginning of sway, and if it crosses the
longitudinal axis once before returning to dead straight, it is sway by
the newsgroup definition, as it's made one oscillation. When it finally
returns to dead straight, whether after one oscillation or ten, the sway
has been damped by some force, or cessation of some force.
> There needs to be a sustained
> oscillation, such as numerous conventionally-hitched trailers exhibit, to fit
> the RV newsgroup definition.
What is 'sustained oscillation'? Is two or more complete cycles, or 4,
or 7, or 15?
I contend that Any movement of the trailer off the ball centerline is
the beginning of sway, and if it crosses dead straight just once, it is
sway. For example, take my rig. I have no sway controls whatever. If I'm
travelling at about 60, a gust of wind or and abrupt steering input on
my part will cause my TT to pivot on the ball, come back across dead
straight maybe once, and then settle down. That's sway. If I'm going 75,
a similar situation results in the TT crossing dead straight a number of
times before settling down. That's also sway.
My rig has never experienced the so-called positive feedback sway, where
succeeding oscillations get larger with each oscillation. I have
however, experienced non-increasing and non-decreasing sway where it
appeared that it was not going to stop until I took some action to make
it stop. This has always been to let off the gas and slow down a few
mph.
> If we allow *any* trailer motion to qualify as "sway," then the term
> becomes totally meaningless, since even turning a corner would qualify as
> "sway"!
And yes, turning a corner is the beginning of sway, but the speed is
generally slow enough that the sway does not continue. Nevertheless,
I've seen long rigs go around corners, and the TT wobbled back and forth
a couple of times before settling down. That's sway.
Sway is not caused only by direct side forces on the trailer, but also
by vertical leaning forces. If you turn any vehicle to the left, it will
lean to some degree to the right, and will nearly always overshoot to
some degree when coming back to vertical. How much it leans and how much
it overshoots and how much horizontal sway this causes depends on the
rig.
My TT is a compact (not as tall as average) and most of the weight in it
is near the floor and frame. Vertical lean does not contribute as much
to sway as it might in other rigs.
Phil: Does the Hensley damp vertical lean? If so, how? Or does it just
damp the horizontal motion caused by vertical lean?
Also, my rig is a living example that, as long as I don't drive to fast,
sway can be damped by natural forces, without dependence on various
devices.
That doesn't mean that I think sway prevention devices are useless,
because they are not. If I were to install a Hensley, I have little
doubt that I could tow faster than I can now. However, 70 is fast enough
for me while towing, and I see no reason to spend $2800 in order to go a
few mph faster, nor to let off the gas every now and then to stop the
minor, but persistent, sway that I get above 70 mph in nearly all but
dead calm conditions.
In any event, if a trailer pivots on the ball, for whatever reason, it's
beginning to sway. If it crosses the centerline even once, and by even a
small amount, when returning, it has swayed. One might even argue that
if it moves off the centerline, and then returns to centerline, without
crossing it, that that is also sway, but I won't be the one to argue
that. But 'sustained', until specifically defined, just doesn't hack it
as a useful word when discussing sway.
I'll concede that a Hensley substantially reduces sway, but before I'll
believe that it eliminates it completely, I'd have to see at least the
following:
A rig that sways at say, 60mph.
Install a Hensley and drive it at 85 with no detectable sway.
Yes, I arbitrarily picked those numbers. Pick 40 and 65 if you like.
> - - - - -
> David, N8DO; FMCA 147762
> djosborn at aol dot com
--
bill
Theory don't mean squat if it don't work.
Robert Carr
There is no RV-newsgroup definition of "sway". You have a definition
of sway in your mind, I have one, Will has one and everyone else has
one. There are obvious overlaps in our definitions, but nobody has
agreed to anything.
You are absolutely correct that if we allow any trailer motion to
qualify as "sway", then the term becomes meaningless. Well, it has
become meaningless or is meaningless, for the purpose of discussing
specific issues, such as hitch configuration. The term "sway" whether
described as under damped oscillation or cyclic mis-tracking does not
offer enough specificity to proceed in a discussion. Sway can, per
Webster, also mean swerve. The example you gave about the trailer
moving to one side and then returning could easily be classed as
swerve(sway). You or I have no right to exclude common definitions.
Therefore it becomes imperative that whomever is talking about sway,
specifically identify in some manner exactly what he/she is talking
about and not rely on some quasi-definition. Don't get me wrong, it is
ok to use the word "sway", but don't necessarily expect the next
person to know what you are talking about. The other person has every
right to include most everything within the definition of the word
"sway". I am sure that some people will refer to sway as the
side-to-side rolling motion of the trailer. Kind of like a tree
swaying in the breeze. Just one possible example.
Bob
On 16 Jun 2000 16:34:44 GMT, djos...@aol.commnet.net (David Osborn)
wrote:
snipped previous references
>
> The real problem here is that things are being called "sway" even though
>they don't fit the RV-newsgroup definition of "sway"!
> Remember, "sway" is an undamped or underdamped oscillation, or a cyclic
>mistracking, of the trailer. A gust of wind from a passing semi (or from
>whatever source) may move the trailer, but if the trailer promptly returns to
>the proper position, then it isn't sway! There needs to be a sustained
>oscillation, such as numerous conventionally-hitched trailers exhibit, to fit
>the RV newsgroup definition.
> If we allow *any* trailer motion to qualify as "sway," then the term
>becomes totally meaningless, since even turning a corner would qualify as
>"sway"!
David Osborn
> If I'm
>travelling at about 60, a gust of wind or and abrupt steering input on
>my part will cause my TT to pivot on the ball, come back across dead
>straight maybe once, and then settle down. That's sway.
It's an oscillation that propmtly ceases. It's neither an undamped or an
underdamped oscillation. It doesn't fit the definition of "sway" that's
existed on these RV newsgroups for many months, and against which no one
(AFAIK) has argued until the last few days.
>My rig has never experienced the so-called positive feedback sway, where
>succeeding oscillations get larger with each oscillation. I have
>however, experienced non-increasing and non-decreasing sway where it
>appeared that it was not going to stop until I took some action to make
>it stop. This has always been to let off the gas and slow down a few
>mph.
That is certainly an undamped oscillation, and it fits the long-standing
RV newsgroup definition of "sway." It's a considerably different animal than
damped oscillation you mentioned just above.
>And yes, turning a corner is the beginning of sway, but the speed is
>generally slow enough that the sway does not continue. Nevertheless,
>I've seen long rigs go around corners, and the TT wobbled back and forth
>a couple of times before settling down. That's sway.
It's not an undamped or underdamped motion. The trailer motion is
properly damped.
>In any event, if a trailer pivots on the ball, for whatever reason, it's
>beginning to sway. If it crosses the centerline even once, and by even a
>small amount, when returning, it has swayed. One might even argue that
>if it moves off the centerline, and then returns to centerline, without
>crossing it, that that is also sway, but I won't be the one to argue
>that. But 'sustained', until specifically defined, just doesn't hack it
>as a useful word when discussing sway.
You may adopt any definition of "sway" you may choose, but your definition
isn't at all consistent with the accepted RV-newsgroup definition. By your
definition, a trailer turning a corner in a campground is beginning to sway,
and that's clearly NOT the case.
Let me illustrate the lack a viability of your definition with a parallel
example. Using your reasoning, a shock absorber on a suspension system would
be malfunctioning if it allowed the suspension to cross the neutral point "even
once, and by even a small amount, when returning." That's clearly *not* how a
properly-designed and functioning shock-absorber operates, and one that *did*
operate in that manner would be totally unsuitable for highway operation.
Likewise, there is no reasonable need for any hitch system to prevent the
trailer from "cross[ing] the centerline even once, and by even a small amount,
when returning." To call that event "sway" is to give "sway" absolutely *no*
useful meaning, and render any discussion of "sway" totally useless!
>I'll concede that a Hensley substantially reduces sway, but before I'll
>believe that it eliminates it completely, I'd have to see at least the
>following:
>A rig that sways at say, 60mph.
>Install a Hensley and drive it at 85 with no detectable sway.
No hitch system that totally eliminates "sway" (according to your
definition) would be practical for towing. It could easily impose forces on
the towing vehicle that would be unsafe under normal driving conditions.
However, one that properly damps trailer oscillations is ideal for towing. It
allows an appropriate amount of properly-damped motion, while eliminating the
undamped or underdamped trailer motion commonly called "sway" that is
irritating and potentially dangerous.
David Osborn
>There is no RV-newsgroup definition of "sway". You have a definition
>of sway in your mind, I have one, Will has one and everyone else has
>one. There are obvious overlaps in our definitions, but nobody has
>agreed to anything.
Nobody (AFAIK) , until the last few days, has challenged the definition
offered many months ago by Mr. Sill, and expanded upon by yourself and at least
one other person.
>You are absolutely correct that if we allow any trailer motion to
>qualify as "sway", then the term becomes meaningless. Well, it has
>become meaningless or is meaningless, for the purpose of discussing
>specific issues, such as hitch configuration. The term "sway" whether
>described as under damped oscillation or cyclic mis-tracking does not
>offer enough specificity to proceed in a discussion. Sway can, per
>Webster, also mean swerve. The example you gave about the trailer
>moving to one side and then returning could easily be classed as
>swerve(sway). You or I have no right to exclude common definitions.
>Therefore it becomes imperative that whomever is talking about sway,
>specifically identify in some manner exactly what he/she is talking
>about and not rely on some quasi-definition. Don't get me wrong, it is
>ok to use the word "sway", but don't necessarily expect the next
>person to know what you are talking about. The other person has every
>right to include most everything within the definition of the word
>"sway". I am sure that some people will refer to sway as the
>side-to-side rolling motion of the trailer. Kind of like a tree
>swaying in the breeze. Just one possible example.
Bob, you and I have nothing further to discuss, because you have chosen to
make "sway" undefined. Should you choose to give "sway" a specific definition,
and then stick with that definition, I'll be happy to discuss the "sway" issue
further.
Hugh
discussion on this newsgroup. Your only aim has been to take aim at Will
Sill whenever you feel like it. This whole thread and all the others
like it on sway, you have posted on, are proof of this. You took Will's
post on definition of sway as another way to "get" Will. It took me
awhile but, now I see your purpose. You once had meaningful input into
this group but, your obsession to "get" Will has overcome your senses.
It's sad to see the disintrigation of a once fruitful mind. May it rest
in peace. As to your dismissal of Bob's most excellent dissertation on
sway, get real.
Hugh
David Osborn wrote:
>
Bob's excellent verbiage snipped
Robert Carr
So by default, we have all adopted a standard definition of sway for
the RV-newsgroup, because David says that we did not challenge Mr.
Sill's definition(as somehow modified), by the appropriate deadline.
Come on.
David, I don't think you wish to discuss anything. However, it sure is
nice to know that I could redeem myself, by accepting some David
decreed definition and then I would be permitted to have further
discussions on the sway issue. How generous.
Nice discussing an issue with you
No response required
Bob
On 16 Jun 2000 20:41:54 GMT, djos...@aol.commnet.net (David Osborn)
wrote:
>rac...@home.com writes:
David Osborn
>David you do not now, have never in the past, been a participant in any
>discussion on this newsgroup. Your only aim has been to take aim at Will
>Sill whenever you feel like it. This whole thread and all the others
>like it on sway, you have posted on, are proof of this. You took Will's
>post on definition of sway as another way to "get" Will. It took me
>awhile but, now I see your purpose. You once had meaningful input into
>this group but, your obsession to "get" Will has overcome your senses.
>It's sad to see the disintrigation of a once fruitful mind. May it rest
>in peace. As to your dismissal of Bob's most excellent dissertation on
>sway, get real.
Hugh,
I am real. I don't see how using Mr. Sill's entirely reasonable
definition of 'sway" is a way to "get" him. The fact is that certain types of
hitches are very effective at minimizing, or eliminating (depending upon your
POV), the undamped or underdamped oscillation commonsly called "sway."
The additional fact is that Mr. Sill has repeatedly stated that the
Hensley Arrow allows "sway," and yet he can't cite even a single instance of a
Hensley Arrow allowing "sway" (as he has defined it). Furthermore, unless I
have missed something, Mr. Sill has never claimed to have *any* actual
experience with the Hensley Arrow, yet he makes authoritative statements
regarding what it will, and won't, do.
My point is quite simple: Mr. Sill should either "put up or shut up." If
he has evidence of the Hensley Arrow allowing "sway" (as he has defined it),
then he should provide it; if he doesn't, then he should stop claiming it does.
In the lack of *any* evidence his claim must be considered just as goofy as
his claim that the truck-tire manufacturers really mean "maximum" every time
they write "minimum."
David Osborn
>David
>
>So by default, we have all adopted a standard definition of sway for
>the RV-newsgroup, because David says that we did not challenge Mr.
>Sill's definition(as somehow modified), by the appropriate deadline.
>Come on.
>
>David, I don't think you wish to discuss anything. However, it sure is
>nice to know that I could redeem myself, by accepting some David
>decreed definition and then I would be permitted to have further
>discussions on the sway issue. How generous.
>
>Nice discussing an issue with you
>
>No response required
Bob,
By default, a definition that's offered and left unchallenged over a long
period of time is accepted. That's how words and phrases get their
definitions. The dictionary doesn't arbitrarily decree that a word or phrase
has a particular meaning; rather, it reflects the commonly accepted usage.
That's all that was done here. "Sway," in the context of towing, refers
to the troublesome tendency that conventional trailers have of wiggling down
the highway. Mr. Sill's definition reflected that, and excluded such things a
lane changes and turns. It's a good, if not perfect, definition of what "sway
control" devices attempt to correct.
As I indicated, if you will give "sway" a definition, and then stick to
it, I'll discuss it with you. (That's *not* a "David decreed" definition --
it's any one you choose to give it. Just be consistent in your usage.)
Bottom line: A discussion is absolutely meaningless unless the words used
are defined, or when the definition is so broad as to include a wide variety of
events or conditions. When words are left undefined, the discussion totally
useless.
Hugh
of discussion, you won't play by any credible rules of discussion, only
your warped set of rules. David, my kids used to play this game, went
something like this, don't like my rules, I'm taking my stuff and
leaving. Sounds an awful lot like your attitude, huh? Sway is anything
from the back end of a trailer "wiggling" down the road to out and out
uncontrolled gyrations. I repeat a theme I've picked up on. Your playing
the "get Will game", plain and simple. You can try to hide it with your
rantings but, it's like dog shit, just because it's on the bottom of
your shoe, one can still smell it.
Hugh (Having more fun than a human is supposed to)
David Osborn wrote:
>
snipped
Tom J
>>I'll concede that a Hensley substantially reduces sway, but
before I'll
>>believe that it eliminates it completely, I'd have to see at
least the
>>following:
>>A rig that sways at say, 60mph.
>>Install a Hensley and drive it at 85 with no detectable sway.
>
> No hitch system that totally eliminates "sway" (according
to your
>definition) would be practical for towing. It could easily
impose forces on
>the towing vehicle that would be unsafe under normal driving
conditions.
You have finally made some sense. Even Phil Sinewe made some
sense one day by making a simular statement, as quoted exactaly,
below:
----------------------------------------
05-14-99
"The problem with believing that you can control the sway that
you will encounter is that sway occurs because of hundreds of
reasons. Trying to eliminate all the causes of sway is not
practical."
Phil Sinewe
http://www.hensleymfg.com
The Ultimate Towing Experience
-----------------------------------------
Put that in your trash burner and smoke on it a while!!
--
tomj...@my-Deja.com
http://homepages.go.com/~tomjanis/
http://homepages.go.com/~aviontravelcade/
Got questions? Get answers over the phone at Keen.com.
Up to 100 minutes free!
http://www.keen.com
gonzo
So far, I've learned alot and also learned to forget a lot.
The NG definition of "sway" can be argued until everyone is blue
in the face and beyond. However, in the context of "does the
Hensley hitch eliminate sway?", whatever definition we agree on
won't matter a bit. Obviously, the hitch eliminates whatever
Hensley defines as "sway".
Now everyone seems to agree that this is one of the two best
damn hitches made... What is being argued now is not what this
thread started off as. Instead of questioning Hensley and it's
reps, this thread is quibbling over the definition of sway as we
see it. So why is so much bandwidth be killed on this
discussion? Mr. Phil, the corporate lackey has abandoned this
discussion quite awhile ago.
Therefore, what I propose is this: Yo!!!! Mr. Phil!!!! Yeah
you. In the back... get up here and define sway as Hensley
defines it.
Now, once he's done that, then and only then can it be argued
that the hitch "eliminates sway" because only then can the NG
definition be rectified with how it's defined by Hensley.
Argue or flame me over anything you want, but the only real
thing that matters is what's contained the paragraph just above
this one. How does Hensley define "sway"?
Mark
mtsof...@aol.com
Robert Carr <rac...@home.com> wrote:
>...I would have to define sway to be exactly what the
>Hensley hitch can eliminate. Otherwise I would have no way to
talk
>about how the Hensley can eliminate sway. In other words, if
the
>definition is set up correctly, the Hensley will prevent the
sway,...."
Robert Carr
Yesterday(6/15) in our discussions I wrote several responses talking
about the need to clearly identify what particular component of sway
was being discussed. At one point(approx. 3:00PM PDT on 6/15) in your
response you indicated stop, there is no use in going any further.
This comment was in direct response to my statement that I thought
Will's definition of "Cyclic Mis-Tracking" included everything. At
that time you conveniently changed the direction of the discussion
toward the driver actions in the witness report that started this
thread. I responded with my initial impressions on including driver
inputs and related some of my response to the wreck. Notice in your
response, at the end ("I appreciate the way you approach this, and
other, discussions. Thanks"). You should appreciate my approach,
because I offered you some ammunition to further support your claim
that Will's report may not be particulary useful as evidence that a
Hensley hitch would allow sway, particularly if the definition of sway
is suitably defined. Check off item 1.
Today you sever the discussion because I will not commit to a sway
definition. All of a sudden my approach is no good. Actually I think
my approach is just fine, just not particularly convenient. You say
that I can have any definition, just stick to it once it is made. In
that context, I would have to define sway to be exactly what the
Hensley hitch can eliminate. Otherwise I would have no way to talk
about how the Hensley can eliminate sway. In other words, if the
definition is set up correctly, the Hensley will prevent the sway,
thereby supporting your contention that Will is wrong. Need item 2
checked off.
Well it isn't going to happen. There are other components to sway that
could easily be described as cyclic mis-tracking and produce an
observable side-to-side oscillation of the trailer, by simply rotating
about the effective hitch point. The Hensley hitch or no other
hitch(Pullrite or fifth wheel) will be able to prevent or stop this
component form of sway. One cause, identified by Will, is
mis-alignment of the trailer axles with respect to the hitch/tongue
centerline. I realize that the component of sway which the Hensley
addresses(steering of tow vehicle by trailer), is probably the most
prominent form for travel trailers. Will even recognizes that this
component (steering of tow vehicle by trailer) is a prominent factor.
But that does not justify confining the description of sway to this
and only this component. In fact, I am just about to the point to let
the sway definition include anything anybody wants, including severe
driving inputs.
These are your words
"Bottom line: A discussion is absolutely meaningless unless the words
used are defined, or when the definition is so broad as to include a
wide variety of events or conditions. When words are left undefined,
the discussion totally useless"
I agree and that is what I have been trying to tell you since I
entered myself into this thread. However, you do not solve this
problem by coming up with some narrow definition that is the official
"RV-newsgroup" definition of sway. Instead, when discussing sway you
make sure that the specific component/type of sway being
discussed(words used") is understood. Therefore the definition of sway
will vary, dependent upon the particular discussion issues. For
example if I am discussing sway in fifth wheel trailers or
semi-trailers, why would I necessarily need a sway definition that
pertains primarily to a travel trailer. That ought to be reasonably
clear.
David, I might be willing to give you some credit in negotiation
skills. In many ways your kind of shrewd, in your capability to steer
a discussion. I will not claim that I have that capability. In this
case, I am convinced that you have been exposed.
I do not particularly like responding to a person in this manner.
However, that is the way I see the situation.
Bob
On 16 Jun 2000 23:39:38 GMT, djos...@aol.commnet.net (David Osborn)
wrote:
snipped previous reference
bill horne
>
> You may adopt any definition of "sway" you may choose, but your definition
> isn't at all consistent with the accepted RV-newsgroup definition.
Baloney. There is no "accepted RV-newsgroup definition". Define
'sustained'.
W F Sill
> How does Hensley define "sway"?
Except as further unnecessary proof that the Hensley marketing team is
a slippery bunch, their definition is irrelevant to the topic, IMO.
The unchallenged fact is that TT's being towed with the Hensley or
PullRite hitch are less likely to get out of line than those behind
conventional hitches. The concept of "sway" has been beaten to the
point that it no longer seems to mean anything to participants in this
discussion, but whether it is self-sustaining, spontaneous, momentary,
cyclic, or whatever, the bottom line issue is not "sway" so much as
trailer *mis-tracking*. No hitch is completely immune to loss of
control.
A trailer is supposed to track the tow vehicle faithfully. When it
doesn't you have a problem, The severity of the problem can vary
from mere annoyance to a fatal wreck. The HA/PullRite hitch systems
dramatically REDUCE mis-tracking from some common causes, but as
proven by known wrecks, cannot and will not ELIMINATE loss of control.
THAT fact is as obvious as a Clinton lie.
Hand-wringing by Sinewe & Osborne about semantics cannot obscure the
truth that Hensley (and perhaps PullRite - I have not seen their ad
material and they don't harangue the NG with wild claims) tells people
their product 'eliminates' sway, 'prevents' crosswinds from affecting
stability, and even protects owners against "radical" steering. Some
readers are not bothered by that because they feel all peddlers lie,
but it bothers me that one of the most important advances in trailer
towing safety is being marketed by a lying batch of sideshow barkers
who are both implicitly and explicitly telling buyers they are getting
protection that no hitch can possibly provide.
Will KD3XR ---- the Curmudgeon of Sill Hill
"Everyone is entitled to his own views. No one
is entitled to his own facts." J. Schlesinger
David Osborn
>These are your words
>
>"Bottom line: A discussion is absolutely meaningless unless the words
>used are defined, or when the definition is so broad as to include a
>wide variety of events or conditions. When words are left undefined,
>the discussion totally useless"
>
>I agree and that is what I have been trying to tell you since I
>entered myself into this thread. However, you do not solve this
>problem by coming up with some narrow definition that is the official
>"RV-newsgroup" definition of sway. Instead, when discussing sway you
>make sure that the specific component/type of sway being
>discussed(words used") is understood. Therefore the definition of sway
>will vary, dependent upon the particular discussion issues. For
>example if I am discussing sway in fifth wheel trailers or
>semi-trailers, why would I necessarily need a sway definition that
>pertains primarily to a travel trailer. That ought to be reasonably
>clear.
>
>David, I might be willing to give you some credit in negotiation
>skills. In many ways your kind of shrewd, in your capability to steer
>a discussion. I will not claim that I have that capability. In this
>case, I am convinced that you have been exposed.
Bob,
Some people choose to define the "beginning of sway" as going around a
corner in a normal fashion. That is clearly an extreme case, and which no
hitch can eliminate. Therefore, if "sway" is left undefined, one can say that
the Hensley Arrow "allows sway" and be completely correct, since it does, in
fact, allow one to go around corners.
No matter what the type of trailer, they are all designed with a flexible
joint between the towing vehicle and the trailer. Therefore, there is no need
for a special definition of "sway" for each type of trailer -- one definition
can, and should, easily fit all. After all, any type of trailer can go around
corners, and any type can change lanes. Please give me your definitions of
"sway" for a conventional trailer and for a semi-trailer, and explain the
difference (and the need for the difference) between the two definitions.
The Hensley Arrow was designed to eliminate (if possible) the troublesome
undamped or underdamped oscillation (UUO) relatively common in conventional
travel trailers. That motion is commonly called "sway." As far as I know, no
one on this newsgroup has offered any credible evidence that the Hensley Arrow
allows that UUO to take place. If he, or anyone else, does, then I would like
to see it.
David Osborn
>David Osborn wrote:
>
>>
>> You may adopt any definition of "sway" you may choose, but your
>definition
>> isn't at all consistent with the accepted RV-newsgroup definition.
>
>Baloney. There is no "accepted RV-newsgroup definition". Define
>'sustained'.
Bill,
You are correct. Your definition of "sway" includes turning a corner as
"the beginning of sway." Clearly, then, the Hensley Arrow allows turning
corners, and therefore "allows sway."
bill horne
Define 'sustained'.
W F Sill
>Define 'sustained'.
The same as "is" but noisier.
8-)
Robert Carr
At this point in time, with all the nonsense about what and what not
to include, I am going to define sway as any mis-tracking of the
trailer with respect to the tow vehicle. The mis-tracking can be
caused by driver inputs, tow vehicle inputs and other forces acting on
or from within the trailer. I don't care whether it is oscillatory in
nature or not. This definition of sway is applicable to all trailer
configurations. When I choose to discuss the subject of sway with
someone else, I will do my best to clarify, specifically, what
particular sway cause/effect component that I am addressing, unless
the other person has already made such a clarification.
As far as what the Hensley hitch was designed to do, referenced to
UUO(undamped or under damped oscillation). In my opinion, the Hensley
hitch was not designed to eliminate UUO. It was designed to eliminate
the steering inputs to the tow vehicle created by the trailer exerting
lateral forces on the hitch point ,the hitch point being typically
located behind the tow vehicle rear bumper. If these steering forces
were not eliminated, UUO could easily take place. However, if these
steering forces are eliminated, UUO can still take place, but for
different causes.
As far as supplying credible evidence that the Hensley will allow UUO.
As I stated earlier in this thread. There is no requirement, except
from you, that evidence from an actual event is required to prove this
point. If you will accept that a trailer can simply oscillate, like a
pendulum on a clock, behind the tow vehicle, then that is all the
proof that is necessary. This has nothing at all to do with trailer
induced steering inputs to the tow vehicle, just simple oscillation
about the hitch pivot point. You, in my opinion, are also playing the
odds that Will or anyone else will be able to come up with an actual
written report that will in no uncertain terms clearly show that a
Hensley hitch will allow UUO. The chances are minuscule. Repeating
myself, the report is not essential anyway.
Bob
On 17 Jun 2000 11:59:07 GMT, djos...@aol.commnet.net (David Osborn)
wrote:
>rac...@home.com (in part):
>
>>These are your words
>>
>>"Bottom line: A discussion is absolutely meaningless unless the words
>>used are defined, or when the definition is so broad as to include a
>>wide variety of events or conditions. When words are left undefined,
>>the discussion totally useless"
>>
>>I agree and that is what I have been trying to tell you since I
>>entered myself into this thread. However, you do not solve this
>>problem by coming up with some narrow definition that is the official
>>"RV-newsgroup" definition of sway. Instead, when discussing sway you
>>make sure that the specific component/type of sway being
>>discussed(words used") is understood. Therefore the definition of sway
>>will vary, dependent upon the particular discussion issues. For
>>example if I am discussing sway in fifth wheel trailers or
>>semi-trailers, why would I necessarily need a sway definition that
>>pertains primarily to a travel trailer. That ought to be reasonably
>>clear.
>>
>>David, I might be willing to give you some credit in negotiation
>>skills. In many ways your kind of shrewd, in your capability to steer
>>a discussion. I will not claim that I have that capability. In this
>>case, I am convinced that you have been exposed.
>
>Bob,
> Some people choose to define the "beginning of sway" as going around a
>corner in a normal fashion. That is clearly an extreme case, and which no
>hitch can eliminate. Therefore, if "sway" is left undefined, one can say that
>the Hensley Arrow "allows sway" and be completely correct, since it does, in
>fact, allow one to go around corners.
> No matter what the type of trailer, they are all designed with a flexible
>joint between the towing vehicle and the trailer. Therefore, there is no need
>for a special definition of "sway" for each type of trailer -- one definition
>can, and should, easily fit all. After all, any type of trailer can go around
>corners, and any type can change lanes. Please give me your definitions of
>"sway" for a conventional trailer and for a semi-trailer, and explain the
>difference (and the need for the difference) between the two definitions.
> The Hensley Arrow was designed to eliminate (if possible) the troublesome
>undamped or underdamped oscillation (UUO) relatively common in conventional
>travel trailers. That motion is commonly called "sway." As far as I know, no
>one on this newsgroup has offered any credible evidence that the Hensley Arrow
>allows that UUO to take place. If he, or anyone else, does, then I would like
>to see it.
>
>
>
>
>
>
>
>
>
David Osborn
>>
>> red...@rye.net writes:
>>
>> >David Osborn wrote:
>> >
>> >>
>> >> You may adopt any definition of "sway" you may choose, but your
>> >definition
>> >> isn't at all consistent with the accepted RV-newsgroup definition.
>> >
>> >Baloney. There is no "accepted RV-newsgroup definition". Define
>> >'sustained'.
>>
>> Bill,
>> You are correct. Your definition of "sway" includes turning a corner
>as
>> "the beginning of sway." Clearly, then, the Hensley Arrow allows turning
>> corners, and therefore "allows sway."
>> David, N8DO; FMCA 147762
>> djosborn at aol dot com
>
Bill,
There's no need for me to define "sustained," since it doesn't appear in
your definition of "sway." Since turning a corner is "the beginning of sway,"
the meaning of "sustained" is totally irrelevant to any discussion of "sway."
Robert Carr
Go to the US Patent Office website at www.uspto.gov and look up Patent
# 4722542 (Trailer Hitch Assembly)(see procedure below). Read the
entire document if you wish. I will point you to the most informative
sections. Read the "Abstract", "Background of Invention" and "Summary
of Invention" sections. I think you can conclude, with ease, what the
Hensley hitch was designed to accomplish.
Procedure:
At website home page, click on "Patents"
Click on the title box containing"Patent Information and Searchable
Databases"
Click on "Patent Number Search"
Enter 4,722,542
Click on "Search"
When search results are displayed, click on "Trailer Hitch Assembly"
Bob
On Sat, 17 Jun 2000 17:28:01 GMT, Robert Carr <rac...@home.com>
wrote:
>David
>
snipped non-relevant section of reference
>
>As far as what the Hensley hitch was designed to do, referenced to
>UUO(undamped or under damped oscillation). In my opinion, the Hensley
>hitch was not designed to eliminate UUO. It was designed to eliminate
>the steering inputs to the tow vehicle created by the trailer exerting
>lateral forces on the hitch point ,the hitch point being typically
>located behind the tow vehicle rear bumper. If these steering forces
>were not eliminated, UUO could easily take place. However, if these
>steering forces are eliminated, UUO can still take place, but for
>different causes.
>
snipped non-relevant section of reference
>
>Bob
>
>
snipped previous reference
David Osborn
>At this point in time, with all the nonsense about what and what not
>to include, I am going to define sway as any mis-tracking of the
>trailer with respect to the tow vehicle. The mis-tracking can be
>caused by driver inputs, tow vehicle inputs and other forces acting on
>or from within the trailer. I don't care whether it is oscillatory in
>nature or not.
Bob,
That's a fine definition, but since it includes turning a corner as
"sway," (since you previously indicated that a trailer tracks to the inside
during a turn and is therefore "mistracking"), it's of essentially zero
practical use to discuss it. Given that your definition of "sway" includes the
action a trailer makes when turning, I'll gladly admit that the Hensley Arrow
Robert Carr
I didn't mean to ignore your response. I would have no problem with
Hensley defining the "sway" that they claim to eliminate, as long as
it is a clear description that doesn't invoke other undefined terms,
such as "Fishtailing", etc. If they were to do so, it should clear the
air on what the hitch was designed to accomplish, with regard to sway.
I have come to believe, in the several years of discussing this issue,
that a clear description would be appropriate. I have tried my best to
relate what I think it means, but I did not make the claims and do not
work for Hensley. I, obviously can not read their minds or know what
was on their minds when they made their claims. They, without doubt,
are the best source to address this issue.
Bob
>>...I would have to define sway to be exactly what the
>>Hensley hitch can eliminate. Otherwise I would have no way to
>talk
>>about how the Hensley can eliminate sway. In other words, if
>the
>>definition is set up correctly, the Hensley will prevent the
bill horne
>
> >David Osborn wrote:
> >>
> >> red...@rye.net writes:
> >>
> >> >David Osborn wrote:
> >> >
> >> >>
> >> >> You may adopt any definition of "sway" you may choose, but your
> >> >definition
> >> >> isn't at all consistent with the accepted RV-newsgroup definition.
> >> >
> >> >Baloney. There is no "accepted RV-newsgroup definition". Define
> >> >'sustained'.
> >>
> >> Bill,
> >as
> >> "the beginning of sway." Clearly, then, the Hensley Arrow allows turning
> >> - - - - -
> >> David, N8DO; FMCA 147762
> >> djosborn at aol dot com
> >
>
> Bill,
> There's no need for me to define "sustained," since it doesn't appear in
> your definition of "sway." Since turning a corner is "the beginning of sway,"
> - - - - -
> David, N8DO; FMCA 147762
> djosborn at aol dot com
I was attempting to understand:
"There needs to be a sustained oscillation, such as numerous
conventionally-hitched trailers exhibit, to fit the RV newsgroup
definition."
Define 'sustained'.
Robert Carr
I would not expect to see much discussion of sway as it relates to
turning a corner, other than warning some new Hensley owner, that when
turning a corner, be careful and make wider turns since the trailer
tracks more to the inside, than when using a conventional behind the
bumper hitch.
Bob
On 17 Jun 2000 18:17:44 GMT, djos...@aol.commnet.net (David Osborn)
wrote:
snipped previous reference
> That's a fine definition, but since it includes turning a corner as
>"sway," (since you previously indicated that a trailer tracks to the inside
>during a turn and is therefore "mistracking"), it's of essentially zero
>practical use to discuss it. Given that your definition of "sway" includes the
>action a trailer makes when turning, I'll gladly admit that the Hensley Arrow
bill horne
>
> To any one that is interested
>
> Go to the US Patent Office website at www.uspto.gov and look up Patent
> # 4722542 (Trailer Hitch Assembly)(see procedure below). Read the
> entire document if you wish. I will point you to the most informative
> sections. Read the "Abstract", "Background of Invention" and "Summary
> of Invention" sections. I think you can conclude, with ease, what the
> Hensley hitch was designed to accomplish.
>
> Procedure:
>
> At website home page, click on "Patents"
> Click on the title box containing"Patent Information and Searchable
> Databases"
> Click on "Patent Number Search"
> Enter 4,722,542
> Click on "Search"
> When search results are displayed, click on "Trailer Hitch Assembly"
>
> Bob
"This has the effect of placing the effective pivot point for the
trailer ahead of the actual hitch assembly, which in turn enhances the
stability of the combination tow vehicle and trailer, rendering it less
susceptible to swaying or fishtailing in the presence of side winds."
It also says this:
"...converge and indeed if projected forwardly would meet along the
centerline m of the tow vehicle B somewhat ahead of the rear bumper 8,
but most likely behind the axis x for the rear wheels 6, assuming of
course that the trailer A is aligned with the tow vehicle B, that is
directly behind the tow vehicle B, as would occur while driving
straight segments of highway. By displacing the pivot point forwardly,
the tendency to sway or fishtail is significantly reduced. Actual tests
of applicant's hitch assembly C have demonstrated a marked reduction
in fishtailing.
Note the presence of 'enhances', 'less susceptable', 'significantly
reduced', marked reduction' , and the absence of 'completely',
'prevents', and 'eliminates'.
Note also the presence of 'somewhat ahead of the rear bumper, but most
likely behind the axis x for the rear wheels', and the absence of 'over
the rear axle'.
It also indicates that, as the turn angle increases, the effective pivot
point moves rearward, and the hitch becomes less of a fiver simulation.
However, sharper angles in normal conditions require lower speeds, and
the propensity to fishtail is less at lower speeds.
The narrative does not seem to address what happens at higher speeds if
the driver should induce larger angles with large and inappropriate
steering inputs. Perhaps the witness account in this thread addresses
that situation.
So what we have here, it appears to me, in the claims of the patent
itself, is what Will has been saying all along (and I paraphrase) - it's
a damn fine hitch which closely simulates a fiver hookup (and may
completely simulate it in some cases, if the existing axle to ball
distance is short enough), and thus significantly reduces sway
(fishtailing), but does not eliminate it and will not compensate for
idiot drivers.
W F Sill
inspection of the Hensley patent papers, and concludes:
>So what we have here, it appears to me, in the claims of the patent
>itself, is what Will has been saying all along (and I paraphrase) - it's
>a damn fine hitch which closely simulates a fiver hookup (and may
>completely simulate it in some cases, if the existing axle to ball
>distance is short enough), and thus significantly reduces sway
>(fishtailing), but does not eliminate it and will not compensate for
>idiot drivers.
Thanx, but I have a confession to make: I cheated. I not only
inspected the hitch in some detail, but because I am slow to
understand miraculous things as explained by Colin's Town Car driver
I studied the patent documents a long time ago. I now realize that
was sneaky and gave me an unfair advantage over those who have no clue
about how things work. I'm as sorry as you can imagine, but being
just a farm boy I hain't smart enuf to invent a lot of stuff outa the
air like those brilliant people selling hitches!
Hugh
the Hensley is not being marketed by Hensley himself?
Hugh
bill horne wrote:
>
snipped
>
> So what we have here, it appears to me, in the claims of the patent
> itself, is what Will has been saying all along (and I paraphrase) - it's
> a damn fine hitch which closely simulates a fiver hookup (and may
> completely simulate it in some cases, if the existing axle to ball
> distance is short enough), and thus significantly reduces sway
> (fishtailing), but does not eliminate it and will not compensate for
> idiot drivers.
>
Robert Carr
I don't disagree with anything you noted or concluded. I further do
not disagree with Will's conclusions. I think, what you just concluded
from reading the patent disclosure and Will's statements are entirely
consistent with what several of us have been trying to convey for some
time on this newsgroup. I would add, as Will mentioned yesterday in
one of the threads, if a person has been following this Hensley thing
over a long period of time, it becomes apparent that some people
mis-interpret what the Hensley is capable of accomplishing. As such,
the motive of Will, myself or anyone else, is an attempt to dispell
such mis-understandings. I also agree that the use of absolutes, such
as eliminate, complete and prevent, are not really appropriate. I am
sure that there are more accurate choices of words that could be used
and essentially convey the required information.
Bob
W F Sill
>If my memory <g> serves me right, wasn't it mentioned some where that
>the Hensley is not being marketed by Hensley himself?
The current marketing people have told me that the gentleman who
invented the hitch (Hensley) is not a part of their organization. No,
I don't have a clue whether he profits from their sales.
Ben Fullerton
past hundred or so postings, I have come to the following opinions:
If I ever go back (from my Class C MH) to an articulated RV setup, I will
not buy a Hensley - as long as there is *any* viable alternative.
Some salespeople are just as creative as the lower level of politicians
when it comes to redefining the language and using it to create false
impressions.
There are several intelligent, experienced and considerate people using
this ng to try to make unsuspecting RV owners aware of the difference
between advertising hype and real-life facts. I don't remember all the
names but Will Sill is at the top of my list.
The Hensley people don't understand how many people there are who are
thoroughly disgusted with misleading advertising hype and will boycott
sellers who overdo it.
As I said - MY opinions.
Ben Fullerton
Robert Carr
I assume you realize that means no ice cream or what ever you prefer
after dinner, for a week. <g>
Bob
On Sat, 17 Jun 2000 20:50:38 GMT, W F Sill <wi...@epix.net> wrote:
snipped previous reference
>
>Thanx, but I have a confession to make: I cheated. I not ...
snipped remainder
David Osborn
>I was attempting to understand:
>
>"There needs to be a sustained oscillation, such as numerous
>conventionally-hitched trailers exhibit, to fit the RV newsgroup
>definition."
>
>Define 'sustained'.
Bill,
You have already given your definition of "sway," and it doesn't include
the word 'sustained," now does it? If you genuinely wish to find the
definition of the word "sustained," then consult your local dictionary. You
will likely find that the dictionary definition fits the common understanding
of it meaning something that's maintained or prolonged.
Note, however, that any discussion of "sustained" is purely academic since
both you and Bob Carr include turns in your definitions of "sway." Given that
definition, the Hensley Arrow fails in "reducing sway," since it allows turns
to occur.
Tom J
Bob, for those that are not going to take the time to read the
whole patent application, I have taken a few important lines out
and posted them here.
"James C. Hensley; (R.R. 2, Box 150, Centralia, IL 62801)"
He is the person that applied for the patent.
Here is part of what he had to say in the abstract:
*********************
"Trailer hitch assembly
Abstract
A hitch assembly for coupling a trailer to a tow vehicle
includes a mounting member positioned firmly at the rear of the
tow vehicle, another mounting member connected to the tongue of
the trailer such that it will not turn relative to the trailer
about a vertical axis, and a pair of short connecting links
which extend between the two mounting members and are pivotally
connected to each. The connecting links are of equal length and
converge forwardly. This has the effect of placing the effective
pivot point for the trailer ahead of the actual hitch assembly,
which in turn enhances the stability of the combination tow
vehicle and trailer, rendering it less susceptible to swaying or
fishtailing in the presence of side winds."
***********************
Note what Mr Hensley had to say about his invention, as compared
to what The current peddlers of the hitch say. He says it is
LESS SUSCEPTIBLE to swaying or fishtailing.
***********************
SUMMARY OF THE INVENTION
One of the principal objects of the present invention is to
provide a trailer hitch assembly which, although being offset
from the rear wheels of the tow vehicle to which it attaches,
enables the towed vehicle to be moved without significant
swaying or fishtailing, even in the presence of substantial side
winds.
***********************
Note again in the summary that, Mr. Hensley says "enables the
towed vehicle to be moved without significant swaying or
fishtailing, even in the presence of substantial side winds.".
He still is not saying that his invention "eliminates" sway as
some contend, only a significant part of it.
***************************
In the details of the drawings:
"By displacing the pivot point forwardly, the tendency to sway
or fishtail is significantly reduced. Actual tests of
applicant's hitch assembly C have demonstrated a marked
reduction in fishtailing."
***************************
In the drawing details, Mr Hensley again says that sway and
fishtail are significantly reduced. No place in the whole
patent papers does Mr Hensley claim that his
invention "eliminates all sway", as the current marketing group,
and some members of this newsgroup claim.
--
tomj...@my-Deja.com
http://homepages.go.com/~tomjanis/
http://homepages.go.com/~aviontravelcade/
Hugh
conventional trailer towing. What I'm surmising from all the info I've
digested is, first the principles behind the design are good, second the
cost is sort of ok as it is a more complex device than others and third,
I've not read a single post that calls it a bad hitch. Owners seem to
like the way it handles towing. Some find their trailer is not quite
rock steady with it, but is still better than with conventional hitches.
My only hope is the present marketers will sell the rights to a real
manufacturing company, with mass marketing skills. This would be a darn
good hitch to include with all trailers over 20' in length. In other
words Ben, don't let the hype stand in your way if you do go back to
travel trailers.
Hugh
bill horne
>
> Bill,
> You have already given your definition of "sway," and it doesn't include
> the word 'sustained," now does it? If you genuinely wish to find the
> definition of the word "sustained," then consult your local dictionary. You
> will likely find that the dictionary definition fits the common understanding
> of it meaning something that's maintained or prolonged.
> Note, however, that any discussion of "sustained" is purely academic since
> both you and Bob Carr include turns in your definitions of "sway." Given that
> definition, the Hensley Arrow fails in "reducing sway," since it allows turns
> to occur.
> - - - - -
> David, N8DO; FMCA 147762
> djosborn at aol dot com
I was attempting to understand:
"There needs to be a sustained oscillation, such as numerous
conventionally-hitched trailers exhibit, to fit the RV newsgroup
definition."
Define 'sustained'.
--
Ben Fullerton
The impression that I had from the various posts was that the Pullright
would provide virtually the same degree of control and for a lower cost.
I agree that the praise of the Hensley was almost as strong as the
condemnation of the misleading advertising. If it was the "only game in
town" then one would be foolish to boycott it, no matter what the reason.
I just think that the most effective way to cut off the overdone hype
would be to expose it to the point that it hurts their sales.
Did I miss something on the Pullright?
Also, if I decide to trailer my MGB rather than flat tow it, is something
that small likely to be subject to excessive "hazardous movement"? (Assume
a low trailer with good shock absorbers and an automobile-type stabilizer
bar on one or both sets of wheels.)
Ben F.
Hugh (hug...@dreamscape.net) wrote:
: Actually Ben, that is too bad. The Hensley is still the best hitch for
Hugh
in some situations might be better than the Hensley. It's only drawback
is the need to buy a new hitch for different tow vehicles and hitches
are not available for all vehicles used to tow.
Sounds like your trailer, for the MGB, is a sound idea. With shocks and
stabilizing bar, it would have the advantage of having brakes as well as
being almost as fast to load and unload as a tow bar and certainly
faster than a tow dolly. Just my opinion.
Hugh
Ben Fullerton wrote:
>
> Thanks for the response.
>
> The impression that I had from the various posts was that the Pullright
> would provide virtually the same degree of control and for a lower cost.
>
snipped
> Did I miss something on the Pullright?
>
> Also, if I decide to trailer my MGB rather than flat tow it, is something
> that small likely to be subject to excessive "hazardous movement"? (Assume
> a low trailer with good shock absorbers and an automobile-type stabilizer
> bar on one or both sets of wheels.)
>
> Ben F.
snipped
Robert C. Thomas
<20000616123444...@ng-fz1.aol.com>...
>
>
> The real problem here is that things are being called "sway" even
though
> they don't fit the RV-newsgroup definition of "sway"!
There IS no "RV newsgroup definition of "sway"".
Robert C. Thomas
> the proper position, then it isn't sway!
>
> It is, in fact, the beginning of sway, and if it crosses the
> longitudinal axis once before returning to dead straight, it is sway by
> the newsgroup definition, as it's made one oscillation.
I've told him this about 50 times. He's either too stupid or too
bullheaded to grasp this concept.
Yer wastin' yer time,
bob
Robert C. Thomas
>
> Let me illustrate the lack a viability of your definition with a
parallel
> example. Using your reasoning, a shock absorber on a suspension system
would
> be malfunctioning if it allowed the suspension to cross the neutral point
"even
> once, and by even a small amount, when returning."
Not malfunctioning, but "bouncing". Your point illustrates your
misunderstanding.
>
> No hitch system that totally eliminates "sway" (according to your
> definition) would be practical for towing.
No one has EVER said that one should. Only that Hensley should stop
bragging that it does. That's so simple even you should understand it.
bob
W F Sill
>Also, if I decide to trailer my MGB rather than flat tow it, is something
>that small likely to be subject to excessive "hazardous movement"? (Assume
>a low trailer with good shock absorbers and an automobile-type stabilizer
>bar on one or both sets of wheels.)
Virtually all of themis-tracking issues that affect TT's apply to car
trailers. If properly balanced, aligned, etc you should have no
problems. I have published my essay on trailer sway so many times
that many readers would probably wish I wouldn't do it again - so send
me email if you can't find it in the dejanews archives & want to read
it.
David Osborn
>There IS no "RV newsgroup definition of "sway"".
That is correct. In fact, a few newsgroup participants are now including
normal turns in the definition of "sway." With that definition, it is
absolutely true that the Hensley Arrow allows "sway," since it does, in fact,
allow one to turn a corner while towing.
For the record, however, the definition of "sway" that has existed here
for many months, which limited the definition of "sway" to "cyclic
mistracking," "fistailing," or "undamped or underdamped oscillation" was left
unchallenged until just the last few days. It was only when it became clear
that there is *zero* evidence of the Hensley Arrow allowing "sway" by that
definition that some here voiced the need for a new, all-inclusive, definition
of sway!
Robert C. Thomas
> ski...@swcp.com writes:
>
> >There IS no "RV newsgroup definition of "sway"".
>
> That is correct. In fact, a few newsgroup participants are now
including
> normal turns in the definition of "sway." With that definition, it is
> absolutely true that the Hensley Arrow allows "sway," since it does, in
fact,
> allow one to turn a corner while towing.
> For the record, however, the definition of "sway" that has existed
here
> for many months, which limited the definition of "sway" to "cyclic
> mistracking," "fistailing," or "undamped or underdamped oscillation" was
left
> unchallenged until just the last few days.
Utter bullshit. I have never seen anyone clearly agree with you that this
is the only type or definition of sway. Having said that, ANY or ALL
things, including going around a curve can cause the trailer. The question
is, does the hitch ALWAYS return the tow to the exact correct position? If
not, this is underdamped oscillation. I've tried to get you to understand
this repeatedly.
It was only when it became clear
> that there is *zero* evidence of the Hensley Arrow allowing "sway" by
that
> definition that some here voiced the need for a new, all-inclusive,
definition
> of sway!
>
More, self serving bullshit. Also untrue.
bob
David Osborn
>David Osborn <djos...@aol.commnet.net> wrote in article
><20000618160915...@ng-bd1.aol.com>...
>> ski...@swcp.com writes:
>>
>> >There IS no "RV newsgroup definition of "sway"".
>>
>> That is correct. In fact, a few newsgroup participants are now
>including
>> normal turns in the definition of "sway." With that definition, it is
>> absolutely true that the Hensley Arrow allows "sway," since it does, in
>fact,
>> allow one to turn a corner while towing.
>> For the record, however, the definition of "sway" that has existed
>here
>> for many months, which limited the definition of "sway" to "cyclic
>> mistracking," "fistailing," or "undamped or underdamped oscillation" was
>left
>> unchallenged until just the last few days.
>
>Utter bullshit. I have never seen anyone clearly agree with you that this
>is the only type or definition of sway. Having said that, ANY or ALL
>things, including going around a curve can cause the trailer. The question
>is, does the hitch ALWAYS return the tow to the exact correct position? If
>not, this is underdamped oscillation. I've tried to get you to understand
>this repeatedly.
It's not my definition. It was made by others.
>It was only when it became clear
>> that there is *zero* evidence of the Hensley Arrow allowing "sway" by
>that
>> definition that some here voiced the need for a new, all-inclusive,
>definition
>> of sway!
>>
>More, self serving bullshit. Also untrue.
Absolutely true. Mr. Carr saw no need to expand the definition until now.