Yokes and dismay with trimming
Jim Logajan
always wondered why the elevator trim mechanisms aren't realistic with
respect to flying smaller planes - it shouldn't have been hard to
accomplish.
In a real C-152 I apply pressure to the yoke to set the desired attitude
and then rotate the trim wheel to trim out the pressure required to hold
that yoke elevator position. But with the CH yoke I have to press a button
while simultaneously allow the yoke to return to its centered position - a
mechanism that I find too unreal. (The CH Sim Yoke has a potentiometer
wheel one might use too, but would not differ in net "feel" from pressing
buttons mapped to elevator trim.)
But I recently noticed that the CH Eclipse Yoke appears to have finally
done what I thought would be the correct thing to do from the start: a trim
wheel that allegedly adjusts the position of the centering springs so that
one could in theory "trim out" control pressure as one would in a real
small GA plane. Except that I found this:
"You may also notice another wheel on the base of the Yoke. This
is a mechanical trim setting for centering the elevator shaft axis
during setup or calibration of the yoke. I have only had to adjust
this once during initial setup but otherwise it will be rarely used. It
is NOT to be used as an elevator trim control."
http://www.chproducts.com/retail/pdf/CH_Eclipse.pdf
I'm not sure what to make of that admonition. One of these days I may just
dismantle my CH Yoke and see how difficult it would be to rig up a proper
mechanical system with the right feel.
Vic Baron
"Jim Logajan" <Jam...@Lugoj.com> wrote in message
news:Xns9E0F73BCA7F2...@216.168.3.30...
Maybe I misunderstand your complaint but the CH yoke trim seems fine to me.
The caution re the thumbwheel has been there since day one on all models -
it is an initial coarse setup adjustment and is rarely needed again.
For me, when flying, if the aircraft is descending, I pull back on the yoke
to maintain level flight and hit the trim button a few times as I release
back pressure and repeat as necessary. I end up with the yoke centered and
the a/c straight and level.
Works just fine.
Vic Baron
"Jim Logajan" <Jam...@Lugoj.com> wrote in message
news:Xns9E0F73BCA7F2...@216.168.3.30...
> I have a CH Products Flight Sim Yoke (not the newer Eclipse Yoke) and have
> always wondered why the elevator trim mechanisms aren't realistic with
> respect to flying smaller planes - it shouldn't have been hard to
> accomplish.
Read another post of yours Jim, and I am now confused. :) - happens a lot
lately.
You say you don't like to have to trim the elevator with buttons while
letting the yoke come back to center.
Are you saying that, in a real aircraft, you pull the yoke back and then
adjust trim so that the yoke stays back without recentering?
IRL you pull the yoke back and trim to remove back pressure - which centers
the yoke. I don't see a difference.
What am I not understanding?
Vic
Andy Hawkins
In article <K02to.253843$pX3.2...@en-nntp-11.dc1.easynews.com>,
Vic Baron<vgb...@hotmail.com> wrote:
> IRL you pull the yoke back and trim to remove back pressure - which centers
> the yoke. I don't see a difference.
Not so. The yoke in a real aircraft doesn't move in response to a trim
adjustment (when using trim in the correct manner). All the trim does is
remove the force required to hold the yoke in that position.
The sequence is:
1. Hold the yoke to get the appropriate attitude.
2. Adjust the trim to remove any pressure required to maintain the yoke in
that position.
3. Take your hands off (effectively).
In flight sim you have to:
1. Hold the yoke to get the appropriate attitude.
2. Adjust the trim, while simultaneously releasing pressure on the yoke to
move it back to the centre position.
The two are subtlely different, but different enough to be very unrealistic
in the flight sim case (when compared to the real world case of a typical
light aircraft).
Andy
sambodidley
"Vic Baron" <vgb...@hotmail.com> wrote in message
news:K02to.253843$pX3.2...@en-nntp-11.dc1.easynews.com...
confused.<g>
Jim Logajan
> "Jim Logajan" <Jam...@Lugoj.com> wrote in message
> news:Xns9E0F73BCA7F2...@216.168.3.30...
>> I have a CH Products Flight Sim Yoke (not the newer Eclipse Yoke) and
>> have always wondered why the elevator trim mechanisms aren't
>> realistic with respect to flying smaller planes - it shouldn't have
>> been hard to accomplish.
>
>
> Read another post of yours Jim, and I am now confused. :) - happens a
> lot lately.
I might be the one confused. :-)
> You say you don't like to have to trim the elevator with buttons while
> letting the yoke come back to center.
Not quite correct - if pressing the buttons actually reduced the pressure I
needed to hold the yoke in a given position I'd be fine with that.
> Are you saying that, in a real aircraft, you pull the yoke back and
> then adjust trim so that the yoke stays back without recentering?
That is my understanding and observation while training in a real C-152.
> IRL you pull the yoke back and trim to remove back pressure - which
> centers the yoke. I don't see a difference.
In the real C-152 I fly, trimming out the pressure does not "center the
yoke." (That may not be the case for modern fly-by-wire aircraft - I have
no knowledge or experience with them.) There is an extra "intuition"
required to accomplish trim on a CH yoke: as you press the trim button you
have to match the yoke's return to center position with the unknown amount
of change you're putting into elevators with the trim button. You have to
pay careful attention to attitude and speed while trimming and correct any
deviations during trimming. IRL I can accomplish trim by feel while
concentrating on other aspects of flying - no movement of the elevator yoke
needed while trimming. The whole point of trimming is that when I'm done, I
can release it and it stays where I put it (along with the plane's speed
and attitude!)
> What am I not understanding?
It may be that I one who is mis-understanding. All I know is that IRL I
have learned that trim is my friend and that with the CH yoke with FS9 it
is a hassle and IMHO physically incorrect.
Ian D
"Jim Logajan" <Jam...@Lugoj.com> wrote in message
Back in the 1990's, I had a CH Flightstick that acted the way
you want. It had two trim wheels, one for elevator, and one
for aileron. When you moved the wheels the spring
centering point moved, so the stick also moved. You would
hold the stick in the desired position, and trim out the
pressure. The trimming was kind of clunky and coarse
compared to a real aircraft, and the pressure didn't change
with changes in airspeed, but it was a good approximation.
That stick also had a throttle slider.
Dallas
> as you press the trim button you
> have to match the yoke's return to center position with the unknown amount
You are completely correct in everything you said... the trimming system
is unrealistic... especially for us 1970's spam can drivers without
electric trim.
Try this... you've got three levers and you're only using two of them,
assign the third one to the trim axis. I found this gives you a more
realistic feel. Yes, you'll have to back the yoke back to center while you
trim, like you do when you're pressing the buttons... But, like a real
airplane, you can move the lever to where you're pretty sure it needs to be
in one movement.
My only problem with this on my system is that the movements aren't fine
enough to really dial-in level flight. I solved this with the payware
FSUIPC which will allow you to make a response curve.. i.e. finer
movements in the center of the axis.
Before you go to the trouble of mechanically modifying your yoke, consider
making a big trim wheel with a potentiometer and connect it via USB using
this:
http://www.leobodnar.com/products/BU0836A/
--
Dallas
Dallas
> One of these days I may just
> dismantle my CH Yoke and see how difficult it would be to rig up a proper
> mechanical system with the right feel.
Yeah... I've been in there.. not much to work with:
http://img.photobucket.com/albums/v101/Dallas52/Potentiometers/InsidetheCHYoke.jpg
--
Dallas
DonK
>In the real C-152 I fly, trimming out the pressure does not "center the
>yoke." (That may not be the case for modern fly-by-wire aircraft - I have
>no knowledge or experience with them.) There is an extra "intuition"
>required to accomplish trim on a CH yoke: as you press the trim button you
>have to match the yoke's return to center position with the unknown amount
>of change you're putting into elevators with the trim button. You have to
>pay careful attention to attitude and speed while trimming and correct any
>deviations during trimming. IRL I can accomplish trim by feel while
>concentrating on other aspects of flying - no movement of the elevator yoke
>needed while trimming. The whole point of trimming is that when I'm done, I
>can release it and it stays where I put it (along with the plane's speed
>and attitude!)
>
>> What am I not understanding?
>
>It may be that I one who is mis-understanding. All I know is that IRL I
>have learned that trim is my friend and that with the CH yoke with FS9 it
>is a hassle and IMHO physically incorrect.
Jim, you just hit on my second biggest disappointment about flying FSX. My biggest disappointment is
that it's not a real airplane. :o(
I have only a little time IRL a/c but my experience is the same as yours. (I also started with
gliders and switched to powered a/c but haven't flown for 30 years) After 6-7 months with FSX I'm
finding it somewhat easier to trim some a/c but it still isn't a "simulation" of my real world
experience. It's just my "half-fast" adaptation to FSX and Saitek's version of simulated trim. I
still find that adequately trimming the higher performance a/c, like the Mooney, is almost
impossible.
I don't know if the CH yoke uses a centering spring but both my Saitek yoke and Saitek stick (CH Pro
Pedals) use them. Other than a mechanical device on the yoke (electric motor??) I don't know how RL
trim could be simulated within FSX for controllers that use centering springs.
IMO, trim is VERY important to the flying experience so, all else being equal, I would buy a
reliable yoke with realistic trim in about one second.
Good post Jim.
Don
Bothell, WA
Walt_M
<Cybnorm@spam_me_not.Hotmail.Com> wrote:
>Before you go to the trouble of mechanically modifying your yoke, consider
>making a big trim wheel with a potentiometer and connect it via USB using
>this:
>http://www.leobodnar.com/products/BU0836A/
That is a handy bit of gear. Thanks for the heads-up Dallas.
Walt
* * *
Offence freely given to those who wish to take it
email: waltK...@live.com
(Replace "K5J4H3K" with "mitty")
sambodidley
"sambodidley" <scoo...@looneyville.com> wrote in message
news:bc9f6$4cb4b175$4b5bc1b2$25...@ALLTEL.NET...
Well, not exactly all of them. The J3 Cub did. The elevator didn't move
on the Cub with trim. The front of the horizontal stabilizer moved up and
down for trim on it. I never really paid that much attention to how the
stick-yoke responded to trim when I was flying. I just trimmed for hands
off control and went about flying the airplane while doing so. That's the
same as I do in FSX. If I don't trim that way in FSX I some times run out
of travel on my control.
ManhattanMan
I never really paid that much attention to how the
> stick-yoke responded to trim when I was flying. I just trimmed for hands
> off control and went about flying the airplane while doing so. That's the
> same as I do in FSX.
Exactly what I was thinking. Logged 160 hrs back in the 60's (95% in
C-150), have been flying sims since mid 80's with a wide variety of
controllers (everything from cheapo joysticks up to a PFC yoke - still
in use after ten years with a USB adapter :) and as long as I can trim
the airplane, I'm a happy camper. I went 45 years without flying IRL,
then had a few hours in a 172 with Varmit back in '07, '08?, shit it was
this century, and it took about 30 seconds to adapt how the trim worked..
Vic Baron
"Andy Hawkins" <an...@gently.org.uk> wrote in message
news:slrnib9br...@atom.gently.org.uk...
Boy, I hate it when I get an attack of OFS - Old Fart Syndrome. Altho I
haven't flown IRL since 1986 (heart attack) I had a slew of time (10K+) in
many different a/c, hard to think I could forget something that basic.
I've just been sitting here with my eyes closed going over the steps I'd
take to trim A Cherokee or C310 and you're absolutely correct ( of course
you knew that) -
I'd pull yoke back with tips of fingers, dial in trim until nothing more
that tip pressure held the yoke "in the same position" not back to center.
Hell to get old - first goes the memory - I forget what's next. :(
Vic
sambodidley
"DonK" <don8...@verizon.net.notvalid> wrote in message
news:rof9b6lvqf075176c...@4ax.com...
One of the most annoying things I have found in FSX is that, on some
planes, when I cut the power the nose doesn't drop like a plane IRL would do
but instead the damn thing tries to go into a loop. It takes full forward
pressure on the control to prevent it. Then it will stabilize and go into a
normal nose down glide angle like it should have done when I first cut the
power. This action sure doesn't simulate any thing I've ever flow IRL.
sambodidley
"ManhattanMan" <um...@binlaid.on> wrote in message
news:At4to.244932$Bh.7...@en-nntp-12.dc1.easynews.com...
Well, I go back quite a bit before that. I got my PPL in 1946 and took
my check ride for the ticket in a J3 Cub. I had never flown anything but
tail draggers until this year. I got a bug in my butt and I went out to the
Angelina Co. airport in Lufkin, Tx and bought an hour of dual with a CFI in
a C172. That was the first time my feet had been off the ground since 1957.
I took off and flew a few maneuvers and then did a few circuits. If I had
been in a J3 instead of a totally foreign, to me, aircraft it would have
seemed like only yesterday.
Sam
Jim Logajan
That saves me a little screwdriver time and the fear of accidently
breaking a perfectly good yoke - thanks. Hmmm. I wonder if it makes
sense to build a wooden box with a tad more room for the extra
mechanical changes I envision, and transplant all the electronics,
switches, yoke, and so on into it.
The other option is to mount a trim wheel mechanism on the right of the
CH plastic box that would change the length of a bungee or spring
wrapped around the end of the yoke's control column. Something like this
(view from the top; excuse the crudity of the ASCII art):
__
/[]\
/ [] \ <--- Bungee wrapped behind control column on back side.
/ [] \ (To minimize side force bungee would have to slide on
--------\ back of shaft, yet still allow rotation of shaft.)
| | {}
| | {} <--- The "{}" is trim wheel mechanism that changes bungee length/pull.
-------- {}
[] <--- Control column on dash side.
O====O <--- Yoke.
But the extra bungee spring force would require use of greater control
forces in all cases. Hmmm. Maybe disconnect the internal springs and use
only the external bungee? Hmmm.
Jim Logajan
> Back in the 1990's, I had a CH Flightstick that acted the way
> you want. It had two trim wheels, one for elevator, and one
> for aileron. When you moved the wheels the spring
> centering point moved, so the stick also moved. You would
> hold the stick in the desired position, and trim out the
> pressure. The trimming was kind of clunky and coarse
> compared to a real aircraft, and the pressure didn't change
> with changes in airspeed, but it was a good approximation.
> That stick also had a throttle slider.
Thanks for the heads-up. I just checked the CH products web site and it
looks like the CH Flightstick Pro is still available and may still have
that feature.
Dallas
> But the extra bungee spring force would require use of greater control
> forces in all cases. Hmmm. Maybe disconnect the internal springs and use
> only the external bungee? Hmmm.
Being a simple guy, I'd go with an electronic solution.. but you would be
correct in saying that's not a physically accurate solution.
All solutions begin with a basic definition of the problem. In this case,
you want to move a spring actuated yoke to a given position, then be able
to adjust the spring pressure back to zero.
I see some sort of movable carriage for the spring set, while the
potentiometer remains directly connected to the yoke shaft, the springs can
move forwards and backwards.
Bungee?... Na... the forces are too variable, from early resistance to
movement being weak, to further extension being strong. I'd say that's why
they all use steel springs.
How much development money do you have?... No one has ever created the
definitive yoke for flight sim. We could corner the market.
--
Dallas
Dallas
> Well, I go back quite a bit before that. I got my PPL in 1946 and took
> my check ride for the ticket in a J3 Cub.
Whoops.. I just deleted your post about inaccurate flight dynamics in
Flight Sim, then I thought of something to say. So I'll say it here...
Trot on over to RealAir and buy their "Scout Package"... just do it...
it's worth three times what they charge for it. All of your complains will
vaporize into distant memories.
http://www.realairsimulations.com
--
Dallas
Dallas
> Boy, I hate it when I get an attack of OFS - Old Fart Syndrome.
Na... you've just re-acclimated to a new reality where Flight Sim is
reality.
--
Dallas
Ian D
"Jim Logajan" <Jam...@Lugoj.com> wrote in message
I don't know if the present sticks are the same. The one I had
used the now defunct joystick port. MIDI sound cards used
the MIDI port as a joystick port also. The mechanism was
fairly simple. The stick operated the pots as in a normal
joystick, with centering springs. The difference was that the
trim wheels moved yokes that the centering springs were
attached to, so the zero tension point could be moved.
Lopez Gomez
news:55dza73pjhkx.1ihttzpqdwdy3$.d...@40tude.net:
I'm glad you posted that photo, as it brings up a related issue I had
with my CH yoke. I had been having problems with (what I thought) were
noisy potentiometers, causing spikes and a very "twitchy" response to
control inputs, especially when applying back pressure. It got bad enough
that I twice stalled my PMDG 747 while trying to flare for landing.
Instead of being able to smoothly raise the nose in the flare, I'd hit
the "bad spot", and the nose would violently jerk to full up pitch, and
I'd slam tail-first into the runway.
So, I took the cover off as you did. I sprayed contact cleaner into the
roll and pitch pots, which did help a little, but the spikes were still
present.
I finally discovered that the actual problem was caused by the fact that
CH uses push-on spade terminals on the potentiometers. They weren't
gripping all that tightly - watching closely while pulling the yoke back,
I could see that the pressure on the wire to the center terminal of the
pitch pot was causing the spade lug to physically slide back and forth on
the terminal with yoke movement.
I proceeded to cut off the spade lugs from the ends of the wires, and
permanently soldered the wires to the terminals on the potentiometers.
The terminals are easily accessible, and it's not at all difficult if one
has some previous experience with soldering.
What a wonderful difference it has made! It eliminated all spikes
completely - the yoke response is now perfectly smooth end-to-end in both
roll and pitch.
I presume that CH uses the push-on terminals to speed assembly of the
yokes in the factory - but those kind of connectors are almost bound to
become a source of trouble over time.
Dallas
> Instead of being able to smoothly raise the nose in the flare, I'd hit
> the "bad spot", and the nose would violently jerk to full up pitch, and
> I'd slam tail-first into the runway.
Nothing ruins the experience worse than a wonky controller.
The cover is off in that photo because that was one of many various tweaks
needed to keep the thing running smoothly. But, overall the CH yoke has
more reliable than most of my other controllers.
--
Dallas
sambodidley
"Dallas" <Cybnorm@spam_me_not.Hotmail.Com> wrote in message
news:1vt9dfokpctc4.13v3h8ie0wbai$.dlg@40tude.net...
Done! I trust your judgment. I flew a perfect circuit on the first flight
and touched down in a perfect 3 point tail dragger landing just as the stall
horn sounded. You can't get much better than that.<g>
Jim Logajan
> On Tue, 12 Oct 2010 14:18:59 -0500, Jim Logajan wrote:
>
>> as you press the trim button you
>> have to match the yoke's return to center position with the unknown
>> amount
>
> You are completely correct in everything you said... the trimming
> system is unrealistic... especially for us 1970's spam can drivers
> without electric trim.
>
> Try this... you've got three levers and you're only using two of
> them, assign the third one to the trim axis. I found this gives you a
> more realistic feel. Yes, you'll have to back the yoke back to center
> while you trim, like you do when you're pressing the buttons... But,
> like a real airplane, you can move the lever to where you're pretty
> sure it needs to be in one movement.
I'll give that a try.
> My only problem with this on my system is that the movements aren't
> fine enough to really dial-in level flight. I solved this with the
> payware FSUIPC which will allow you to make a response curve.. i.e.
> finer movements in the center of the axis.
I have the payware FSUIPC so I should also be able to make the response
non-linear.
> Before you go to the trouble of mechanically modifying your yoke,
> consider making a big trim wheel with a potentiometer and connect it
> via USB using this:
> http://www.leobodnar.com/products/BU0836A/
Thanks - I came across similar solutions elsewhere, such as:
http://www.flightsim.com/main/howto/trimch.htm
http://www.desktopaviator.netfirms.com/Articles/My_Trim_Wheel/index.htm
http://www.flightsim.com/main/howto/cabina.htm#TRIM
Jim Logajan
> On Tue, 12 Oct 2010 20:22:33 -0500, Jim Logajan wrote:
>
>> But the extra bungee spring force would require use of greater
>> control forces in all cases. Hmmm. Maybe disconnect the internal
>> springs and use only the external bungee? Hmmm.
>
> Being a simple guy, I'd go with an electronic solution.. but you
> would be correct in saying that's not a physically accurate solution.
>
> All solutions begin with a basic definition of the problem. In this
> case, you want to move a spring actuated yoke to a given position,
> then be able to adjust the spring pressure back to zero.
>
> I see some sort of movable carriage for the spring set, while the
> potentiometer remains directly connected to the yoke shaft, the
> springs can move forwards and backwards.
That's the kind of mechanism I am considering.
> Bungee?... Na... the forces are too variable, from early resistance
> to movement being weak, to further extension being strong. I'd say
> that's why they all use steel springs.
Agreed.
> How much development money do you have?...
I believe I'm spending it on flight lessons, so pretty soon not very much.
:-)
> No one has ever created
> the definitive yoke for flight sim. We could corner the market.
How big a market would you guess it is, though, and how price sensitive?
Throw in force-feedback and I suspect it would have to have at least a
US$200 to $300 list price. I have no idea if a "definitive" ~$300 yoke
would sell only a few hundred a year, a few thousand, or the tens of
thousands.
sambodidley
"Dallas" <Cybnorm@spam_me_not.Hotmail.Com> wrote in message
news:1vt9dfokpctc4.13v3h8ie0wbai$.dlg@40tude.net...
Dallas,
Have you flown that Scout Tundra out of and back into that little Bear
Creek Aviation strip. I did it on the first try. That thing is a teal
booger.<g>
sambodidley
Oops, that was supposed to be Bear Gulch Aviation. Just type it in for
airport selection. When I looked at that strip I thought they had to be
kidding. But I made it out and back in with the Scout without hitting any
of those trees. It was like threading a needle.
Sam
Dallas
Whoa the first one is too ambitious... before I spent hours drilling holes
in my yoke I'd just pay the $40 to buy that USB circuit board I posted.
I like the second one..
--
Dallas
Dallas
> How big a market would you guess it is, though, and how price sensitive?
> Throw in force-feedback and I suspect it would have to have at least a
> US$200 to $300 list price.
CH Products and Saitek seem to think it was worth making...
And these guys seem to be happy making $400+ yokes..
http://www.flypfc.com/index.php?m_id=2&d_id=29
--
Dallas
Dallas
> Whoa the first one is too ambitious... before I spent hours drilling holes
> in my yoke I'd just pay the $40 to buy that USB circuit board I posted.
Oh.. it looks like this guy made exactly what I was talking about.
http://www.desktopaviator.com/Products/Model_2030/index.htm
Except for the funky looking wheel, it looks like a good thing.
--
Dallas
scatter
> I have a CH Products Flight Sim Yoke (not the newer Eclipse Yoke) and
> have
> always wondered why the elevator trim mechanisms aren't realistic with
>
> respect to flying smaller planes - it shouldn't have been hard to
> accomplish.
If you would be happy with an electronic version similar to this
(obviously not the same)- I wrote a CH trim script for CH gear for Black
Shark. You basically get your controls in position, hold a button and
release them - the controls in the sim stay in position.
It's on my squad's wiki
www.vaaf.net/wiki2/index.php5?title=CH_HOTAS_hardware_trim
Gregory
brought the following to our attention:
>Boy, I hate it when I get an attack of OFS - Old Fart Syndrome. Altho I
>haven't flown IRL since 1986 (heart attack) I had a slew of time (10K+) in
>many different a/c, hard to think I could forget something that basic.
>
>Hell to get old - first goes the memory - I forget what's next. :(
1986!! well yur darn tootin' gettin' old ther. 1986 seems like a long
time ago. Things were going great back then!! What about joints?
Don't the hip joints start acting up?
Back on topic.. there was a line of force feedback sticks. Did they
function like real, or would they just throb in your hand? MS did away
with all its flightsticks. Can't understand it.
-G
Gregory
>Before you go to the trouble of mechanically modifying your yoke, consider
>making a big trim wheel with a potentiometer and connect it via USB using
>this:
>http://www.leobodnar.com/products/BU0836A/
Thanks for reposting.. was looking for that link. You guys have a
soldering iron?
-G
scatter
> Back on topic.. there was a line of force feedback sticks. Did they
> function like real, or would they just throb in your hand? MS did
> away
> with all its flightsticks. Can't understand it.
I'm not sure about msfs but Microsoft's sidewinder ffb pro works quite
well in Black Shark (position changing with trim). If no one else knows,
I could try it in fsx on the weekend.