Flap setting and airspeed in strong winds
Koopas Ly
My CFI told me to use a maximum of 20 deg. flaps on approach in strong
winds, in a 172SP. Why would you reduce the flap setting in strong
winds when landing? What would you quantify as "strong" winds?
Similarly, why would you fly a higher approach speed in GUSTING winds?
Is it because GUSTING winds can cause airspeed fluctuations, which
may lead to unexpected loss of lift, increased sink rate that
translates into a steeper descent? Note that I've only mentioned
gusting winds effects. "Steady" winds effects should only cause
changes in groundspeed that would lead the airplane to land short or
long of the runway should the pilot not take corrective action.
However, the airplane would still be controllable. On the other hand,
I take it that you'd increase your speed to offset gusting *TAILWINDS*
that can cause abrupt 1/ changes in the direction and speed of the
airmass and most importantly 2/ a sudden decrease in indicated
airspeed, which *could* lead to loss of control of the aircraft? Or
perhaps increasing your speed somehow makes the airplane generally
"more stable" [very open to interpretation]. Speaking of
controllability, I guess one wouldn't be so worried with gusting
*headwinds* since they would just result a quick boost of extra lift
and ballooning (which can really screw up an approach but not as much
as being sunk into the ground by tailwinds)
Are gusting winds and windshear synonymous? As I understand,
windshear is the sudden change in wind speed and direction. However,
gusting winds given by say ATIS will still follow the wind direction
and speed. I would fear gusting winds as much as windshear, IMO.
Do you use the rule "add half the gust wind speed to your approach
speed"? What about landing in strong winds with no gusts? In such
case, would you still up your approach speed?
An inquisitive Alex.
kontiki
would be due to gusty winds that can cause "the bottom to drop out"
on short final. The case of an increased headwind is not nearly
the problem of a sudden decreasing headwind (or even shearing
to a tailwind).
In my opinion this effect is most pronounced when the X-wind is
gusting directly accross the runway and shears from a headwind
to a tailwind. Thus, you not only are dealing with gusty direct
crosswind components but are dealing with a headwind-tailwind
components. In this case I will add a few knots to the airspeed
and even try to fly a slightly higher approach (don't want to end
up clipping trees on the end of the runway). You'd be suprised
how the airplane can drop when a headwind shears to a tailwind.
Phil Rynn
due to more control authority. You would need less wing down top rudder if
you are flying a higher airspeed in order to counteract crosswind and
maintain centerline with the nose pointed down the runway. This is a more
prevalent concern when flying multi-engine aircraft when your bank angle on
landing is limited due to the potential of a prop strike. For example in my
aircraft the maximum bank angle for touchdown is 9 degrees IOT avoid prop
strike. Another consideration in larger aircraft is to fly the approach
with extra speed for the reasons you mentioned, but to slow to a normal
touchdown speed. The reason being that extra airspeed = extra landing
ground roll distance. That coupled with the tendency to land long when
carrying extra speed could land you in an uncomfortable situation fairly
quickly if you were landing on a relatively short runway. Lastly, it is
possible to have to touch down in a crab if the crosswinds were high enough.
Definitely the last thing you want to do since landing gear do not take
torsional stress too well.
Phil
"Koopas Ly" <super...@hotmail.com> wrote in message
news:c94c7949.03052...@posting.google.com...
Julian Scarfe
news:c94c7949.03052...@posting.google.com...
> My CFI told me to use a maximum of 20 deg. flaps on approach in strong
> winds, in a 172SP. Why would you reduce the flap setting in strong
> winds when landing? What would you quantify as "strong" winds?
Such recommendations tend to be rooted in a deterioration of roll control
with higher flap settings. Strong winds tend to be gusty winds that change
direction from time to time, so roll response tends to be more of an issue.
With a hypothetical perfectly steady strong wind, there would be no point in
reducing flap setting.
Julian Scarfe
Andrew Sarangan
> Hello everyone,
>
> My CFI told me to use a maximum of 20 deg. flaps on approach in strong
> winds, in a 172SP. Why would you reduce the flap setting in strong
> winds when landing? What would you quantify as "strong" winds?
Anything that approaches the maximum demonstrated crosswind can be
considered as strong wind. Of course, this is an arbitrary definition.
In strong cross winds, a faster landing speed will help maintain
directional control by giving more rudder authority. This is why less
flaps is generally recommended.
>
> Similarly, why would you fly a higher approach speed in GUSTING winds?
> Is it because GUSTING winds can cause airspeed fluctuations, which
> may lead to unexpected loss of lift, increased sink rate that
> translates into a steeper descent? Note that I've only mentioned
> gusting winds effects. "Steady" winds effects should only cause
> changes in groundspeed that would lead the airplane to land short or
> long of the runway should the pilot not take corrective action.
> However, the airplane would still be controllable. On the other hand,
> I take it that you'd increase your speed to offset gusting *TAILWINDS*
> that can cause abrupt 1/ changes in the direction and speed of the
> airmass and most importantly 2/ a sudden decrease in indicated
> airspeed, which *could* lead to loss of control of the aircraft? Or
> perhaps increasing your speed somehow makes the airplane generally
> "more stable" [very open to interpretation]. Speaking of
> controllability, I guess one wouldn't be so worried with gusting
> *headwinds* since they would just result a quick boost of extra lift
> and ballooning (which can really screw up an approach but not as much
> as being sunk into the ground by tailwinds)
Gust implies a sudden change in wind speed or direction. If the wind
is 10G20, you could potentially lose or gain 10 knots of airspeed.
Since losing 10 knots is more hazardous than gaining 10 knots, we add
5 knots to the approach speed. Now, a 10 knot gust will can put us 5
knots too slow, or 15 knots too fast. The theory is that, the 15 knots
of excess speed is offset by the steady portion of the headwind. On
the other hand, if the wind is 0G10, then you have a real problem
because 15 knots too fast can make you go off the runway.
>
> Are gusting winds and windshear synonymous? As I understand,
> windshear is the sudden change in wind speed and direction. However,
> gusting winds given by say ATIS will still follow the wind direction
> and speed. I would fear gusting winds as much as windshear, IMO.
Windshear is a change in wind speed or direction as a function of
altitude. Wind gust is a change in wind speed or direction as a
function of time at the same altitude (generally ground level).
Wind shear is encountered as you descend on one moving airmass into
another.
The effects of wind shear and wind gusts are the same. They result in
a loss or gain of airspeed.
>
> Do you use the rule "add half the gust wind speed to your approach
> speed"? What about landing in strong winds with no gusts? In such
> case, would you still up your approach speed?
>
Generally, there is no need to add gust factor if there is no gust.
However, you can expect wind gusts any time there is strong winds.
>
> An inquisitive Alex.
EDR
> winds, in a 172SP.
> Why would you reduce the flap setting in strong winds when landing?
To reduce drift. The more flaps you have hanging out, the slower your
stall speed, the greater effect the wind will have on pushing your
aircraft in the direction of flow.
> What would you quantify as "strong" winds?
I would say anything greater than the demonstrated crosswind speed,
regardless of whether it is a direct headwind or direct crosswind.
> Similarly, why would you fly a higher approach speed in GUSTING winds?
> Is it because GUSTING winds can cause airspeed fluctuations, which
> may lead to unexpected loss of lift, increased sink rate that
> translates into a steeper descent?
Yes, and no. A higher sink rate does not necessarily mean your angle of
attack will change.
> Are gusting winds and windshear synonymous?
Not necessarily. Wind shear is a sudden change in direction of (I
think) 30 degrees or more.
> Do you use the rule "add half the gust wind speed to your approach
> speed"?
All the steady and half the gust.
> What about landing in strong winds with no gusts? In such case,
> would you still up your approach speed?
Depends. How long is your runway? What obstacles do you have to clear
to get to the threshhold? Are you going to use less than full flaps?
Dan Thomas
The pilot should be paying attention to the windsock or wind
triangle or the tower regarding surface winds. Wind shear has to do
with changes in wind speed and direction with ALTITUDE, so that as you
descend or climb the aircraft experiences temporary airspeed changes.
Most commonly you'll find a decrease in wind as you approach the
surface, and the indicated airspeed will drop and the aircraft will
sink. Flying too close to the stall can make things interesting. With
full flap, the drag can be great enough that adding power results in
only marginal airspeed recovery. At 20 degrees in a 172, the stall
speed has been lowered almost as much as at 40 degrees, without all
the drag.
Sometimes you'll find that winds aloft are in a direction
opposite to that on the ground. This will normally result in a long,
fast approach as the high groundspeed generated while flying in the
upper air mass is not easily lost as the aircraft passes into the
lower mass, especially if the shear zone is close to the ground. We
sometimes find it as low as 50 feet. It will normally start at 6 or
700 feet early in the morning, and lower gradually with daytime
heating until the zone contacts the surface. If there is significant
windspeed difference between the masses, turbulence is higher and near
the surface this can cause control problems.
Any buildings, trees or whatever will create turbulence that is
unpredictable, and many airplanes have been broken by unsuspecting
pilots. Be aware of the wind'd direction, and think of the air as
water flowing overrocks in a stream; you'll start to watch upwind
obstacles as you approach the runway.
Dan
TheMadTexan
With a strong wind condition, you can maintain a higher airspeed and have
your ground speed remain reasonable. At this higher airspeed, flaps are not
required to maintain adequate lift. Since you don't need them, and they
definately negatively impact the controlability of the aircraft, don't use
them. Remember, what you care about at touchdown is *groundspeed* and
alignment with that centerline. You only focus on airspeed on final because
you don't want to stall/spin so close to the ground (which is of course
vitally important!), but at the moment of touchdown airspeed is almost
irrelevant.
Personally, I almost never exceed 20 degrees of flaps in a Skyhawk, even on
a calm day (pull the little black knob - it will come down). In windy
conditions, I frequently land with 10 or no flaps. Yes this requires more
runway, but the Skyhawk needs so little to begin with (a.k.a. the dumb thing
is already so slow) that I find this to be perfectly safe at most airports.
If the runway isn't there, the 30 (and in some models 40) degrees of flaps
come in for sure. You should practice no flap landings anyway. They are
electrical in the 172SP, which means they won't work they day you find
yourself with a fouled up electrical system.
On my checkride, I had about an 18 knot headwind for my C-152 to fight on
final. The only time I used any flaps was for my short field landing. My
IAS was 54 knots going into the flare - but I'm not sure the tires made a
complete revolution before we were stopped! My DPE laughed and asked me if
I was trying to get an airship ticket while we were at it...
"Koopas Ly" <super...@hotmail.com> wrote in message
news:c94c7949.03052...@posting.google.com...
Mike Rapoport
"EDR" <er...@rrohio.com> wrote in message
news:260520031007396008%er...@rrohio.com...
> > My CFI told me to use a maximum of 20 deg. flaps on approach in strong
> > winds, in a 172SP.
> > Why would you reduce the flap setting in strong winds when landing?
>
> To reduce drift. The more flaps you have hanging out, the slower your
> stall speed, the greater effect the wind will have on pushing your
> aircraft in the direction of flow.
>
What???
Mike
MU-2
G.R. Patterson III
Koopas Ly wrote:
>
> My CFI told me to use a maximum of 20 deg. flaps on approach in strong
> winds, in a 172SP. Why would you reduce the flap setting in strong
> winds when landing?
Using less flaps gives you a higher airspeed. This gives the controls more
authority. It also puts you on the ground at a higher speed, which gives you
more control.
> What would you quantify as "strong" winds?
I would say anything over about a 7 knot crosswind component or 15 knots
total, whichever is lower.
> Similarly, why would you fly a higher approach speed in GUSTING winds?
> Is it because GUSTING winds can cause airspeed fluctuations, which
> may lead to unexpected loss of lift, increased sink rate that
> translates into a steeper descent?
Yep. Also gives you more control for handling gusts from the side.
> I take it that you'd increase your speed to offset gusting *TAILWINDS*
> that can cause abrupt 1/ changes in the direction and speed of the
> airmass and most importantly 2/ a sudden decrease in indicated
> airspeed, which *could* lead to loss of control of the aircraft?
Doesn't matter if the gust comes on the nose or the tail. If you get a gust
from the rear, you will get a rapid decrease in airspeed, which is not good.
You fixe this by applying power. When the gust dies, you need to get off the
power. If you don't do that rapidly enough, you will gain altitude.
If the gust comes from the front, you will get an increase in airspeed, but
it will decrease again when the gust dies. If you reacted to the gust from
the front by decreasing power and slowing down, you will now be too slow and
you'll start losing altitude.
If you're getting gusts from the side, you will have to handle this with the
controls (mainly rudder). The higher your airpseed, the more rudder authority
you have.
> Do you use the rule "add half the gust wind speed to your approach
> speed"?
I usually do. That rule also applies to departing, by the way. If I'm taking
off in gusting winds in the 20 knot range, I will use no flaps (instead of
the 24 degrees which is usual for my aircraft), and I will climb out at
100 mph or more instead of 90 (which is best ROC for my plane). That puts me
leaving the ground at about 85 mph instead of my usual 65. That's for a
Maule, not a Cessna.
> What about landing in strong winds with no gusts? In such
> case, would you still up your approach speed?
Yes, but in that case, I do it because I don't want to spend all day on my
final approach.
George Patterson
If you always tell the truth, you never have to remember what you said.
Samuel Clemens
Gary L. Drescher
> > speed"?
>
> All the steady and half the gust.
Really? So with a steady 25-knot headwind, you'd add 25 knots to your
approach airspeed? If you're flying anything like a 172 or a Warrior,
you're going to float all the way to the departure end of the runway.
G.R. Patterson III
"Gary L. Drescher" wrote:
>
> Really? So with a steady 25-knot headwind, you'd add 25 knots to your
> approach airspeed? If you're flying anything like a 172 or a Warrior,
> you're going to float all the way to the departure end of the runway.
With a 25 knot headwind, he's going to be able to get that speed off in
the first 100' or so of runway.
Michael 182
"Gary L. Drescher" <GLDre...@deja.com> wrote in message
news:Z2qAa.3815$_t5....@rwcrnsc52.ops.asp.att.net...
> Really? So with a steady 25-knot headwind, you'd add 25 knots to your
> approach airspeed? If you're flying anything like a 172 or a Warrior,
> you're going to float all the way to the departure end of the runway.
Why? I'm not advocating this technique, but if the winds steady there's no
reason you'll land longer.
Michael
Rick Durden
Your instructor is correct in adding some speed in gusting winds,
although the most common error is to add too much...and too fast on
final is the cause of a very high proportion of landing accidents.
Add half the gust factor. If the wind is at 10, gusting to 20, the
gust factor is 10, so add 5 to your normal approach speed. The
problem when a gust end your airspeed drops. Fortunately, in light
airplanes such as we fly, it's not a big problem as it can be in
larger aircraft and jets, so it is not necessary to add much speed.
Where you instructor is incorrect is in having you reduce the flap
being used. If he goes into NTSB accident reports on landing
accidents he'll find that as flap deflection decreases the number of
landing accidents increases. The reason is that the problem pilots
perceive is not the true risk they face. Pilots get worried about
controlling the airplane when they fly final, so they add speed and
reduce flaps for "more control". The reality is that they have plenty
of control at the normal approach speed with full flaps. The problem
comes when they touch down fast, with partial flaps, because they are
far more likely to lose control during rollout or go off the end of
the runway. Very, very few accidents occur because the pilot had
control difficulties on final in a gusty crosswind. A lot occur
because he landed fast, with partial flaps, and then ran off the
runway and hit something.
All the best,
Rick
super...@hotmail.com (Koopas Ly) wrote in message news:<c94c7949.03052...@posting.google.com>...
Gary L. Drescher
news:DmqAa.988621$F1.120285@sccrnsc04...
Sure there is. Let's compare a 60-knot no-wind approach with an 85-knot,
25-knot headwind approach, assuming a stall speed of say 45 knots. In the
first case, you float while your ground speed goes from 60 to 45 knots; but
in the second case, you float while your ground speed goes from 60 to 20
knots. If you now ignore the wind and just think in terms of those speeds
relative to the ground, it's clear that the second case takes up more
distance, as well as more time, assuming roughly equal rates of
deceleration. (Granted, I did exaggerate the difference in my previous
post, however.)
--Gary
Michael 182
> "Michael 182" <mhor...@attbiNOSPAMALLOWED.com> wrote in message
> news:DmqAa.988621$F1.120285@sccrnsc04...
> >
> > "Gary L. Drescher" <GLDre...@deja.com> wrote in message
> > news:Z2qAa.3815$_t5....@rwcrnsc52.ops.asp.att.net...
> > > "EDR" <er...@rrohio.com> wrote in message
> > > news:260520031007396008%er...@rrohio.com...
>
> 25-knot headwind approach, assuming a stall speed of say 45 knots. In
the
> first case, you float while your ground speed goes from 60 to 45 knots;
but
> in the second case, you float while your ground speed goes from 60 to 20
> knots. If you now ignore the wind and just think in terms of those
speeds
> relative to the ground, it's clear that the second case takes up more
> distance, as well as more time, assuming roughly equal rates of
> deceleration.
I don't know the math, but it is not clear to me it takes more distance,
just more time. If I'm heading into a 25 knot headwind, then the additional
time may not cause additional distance. Any math majors want to post the
right answer?
Michael
Greg Esres
strong winds, in a 172SP. >>
Most instructors make recommendations such as those because that's
what they were taught. That bugs me. ;-)
I use full flaps regardless of the winds, and have never had a
problem. But you need to get the flaps up quickly once you touch
down.
True, roll response is theoretically lower with flaps, but you have
plenty of roll response, so a little less is no big deal. On the plus
side, flaps reduce the dihedral effect (theoretically), and will thus
make the plane easier to maintain in a sideslip.
G.R. Patterson III
"Gary L. Drescher" wrote:
>
> Sure there is. Let's compare a 60-knot no-wind approach with an 85-knot,
> 25-knot headwind approach, assuming a stall speed of say 45 knots.
Well, if I'm coming in faster, I will be using less flaps, which will result
in a higher stall speed. Coming in at 85 knots, I would use my cruise flap
setting, which gives me a stall speed about 15 knots higher than my full
flap setting. Again, that's with my aircraft, not a 172.
Gary L. Drescher
news:3ED240A0...@comcast.net...
>
>
> "Gary L. Drescher" wrote:
> >
> > Sure there is. Let's compare a 60-knot no-wind approach with an
85-knot,
> > 25-knot headwind approach, assuming a stall speed of say 45 knots.
>
> Well, if I'm coming in faster, I will be using less flaps, which will
result
> in a higher stall speed. Coming in at 85 knots, I would use my cruise flap
> setting, which gives me a stall speed about 15 knots higher than my full
> flap setting. Again, that's with my aircraft, not a 172.
True, I was making a comparison that assumed similar configurations except
for trim speed.
--Gary
Roger Halstead
It's a double edged sword. I was taught, "If you got 'em, us 'em" and
never had a problem. I'm not saying that is the best approach, it's
just what I was taught.
Roger Halstead (K8RI EN73 & ARRL Life Member)
www.rogerhalstead.com
N833R World's oldest Debonair? (S# CD-2)
>
>Julian Scarfe
>
David Megginson
> It's a double edged sword. I was taught, "If you got 'em, us 'em"
> and never had a problem. I'm not saying that is the best approach,
> it's just what I was taught.
When I was doing my primary training on 172's, I found crosswind
landings in gusty winds extremely hairy with the big Fowler flaps
extended, possibly because of the different lift characteristics.
I don't notice much of a problem with the small flaps on my PA-28, but
it's hard to separate from all the other differences in crosswind
handling.
All the best,
David
--
David Megginson, da...@megginson.com, http://www.megginson.com/
Gary L. Drescher
Michael, picture it this way. Imagine two planes landing in parallel on 36L
and 36R. Pretend there's a big glass wall between them, with calm winds to
the left of the wall and wind 360 at 25 to the right of the wall. On
approach, both planes are abeam each other with the same ground speed (60
knots). As long as their ground speeds are the same and their directions
parallel, they must remain abeam each other. So as they reach the runway
and their ground speeds decline together from 60 to 45 knots, they remain
abeam each other. But at 45 knots ground speed, the plane on 36L touches
down, while the plane on 36R keeps floating until its ground speed declines
further to 20 knots. Since the planes were still abeam each other when the
one on 36L touched down, the one on 36R clearly travels further than its
partner before it too touches down.
--Gary
> Michael
>
>
David Megginson
> Michael, picture it this way. Imagine two planes landing in parallel on 36L
> and 36R. Pretend there's a big glass wall between them, with calm winds to
> the left of the wall and wind 360 at 25 to the right of the wall. On
> approach, both planes are abeam each other with the same ground speed (60
> knots). As long as their ground speeds are the same and their directions
> parallel, they must remain abeam each other. So as they reach the runway
> and their ground speeds decline together from 60 to 45 knots, they remain
> abeam each other. But at 45 knots ground speed, the plane on 36L touches
> down, while the plane on 36R keeps floating until its ground speed declines
> further to 20 knots. Since the planes were still abeam each other when the
> one on 36L touched down, the one on 36R clearly travels further than its
> partner before it too touches down.
I might have missed the specific point you were discussing at the
start, but if you're talking about landing rather than just touching
down, the planes still need to decelerate after touchdown. The plane
on 36L will have a long landing roll, while the plane on 36R will
need, maybe, 100ft to get down to taxi speed.
Peter Duniho
news:JAnAa.12846$Mu3.2...@newsfep4-glfd.server.ntli.net...
> With a hypothetical perfectly steady strong wind, there would be no point
in
> reducing flap setting.
Not strictly true.
One of the effects of a strong headwind is to steepen the descent angle, all
else being equal. Since flaps also steepen the descent angle, a pilot
wishing to fly a consistent approach may find that making the approach with
reduced flaps allows them to maintain a similar descent angle that they
would find in a no-wind approach, without a need for greatly increased
power.
Pete
Gary L. Drescher
news:87znl9s...@megginson.com...
That's true. Still, the plane on 36L goes from 45 to 20 knots on the
ground, whereas the plane on 36R goes from 45 to 20 knots ground speed while
still in the air. Since you can decelerate more rapidly on the ground, that
portion of the decleration takes less time and distance for the 36L plane
than for the 36R plane.
--Gary
Michael 182
Michael
"Gary L. Drescher" <GLDre...@deja.com> wrote in message
news:1ZrAa.1027395$S_4.1036982@rwcrnsc53...
Rick Durden
>>Using less flaps gives you a higher airspeed. This gives the
controls more
authority. It also puts you on the ground at a higher speed, which
gives you
more control.<<
Sadly, a common misconception. Putting you on the ground at greater
speed gives you LESS control. The vast majority of landing crashes
involve touchdowns at high speed and loss of control or running out of
runway. You have the best control of the aircraft by touching down
as slowly as possible. The aerodynamic controls are still fully
effective (but you have to be willing to use them and most pilots
aren't) and you are slowed to a point where you actually have rolling
control.
For some reason pilots like to land fast. And we keep werecking
airplanes because of it. The exposure is during decleration to taxi
speed from touchdown speed. The faster you touch down, the longer
the period of exposure and the more likely a pilot is to lose
control. Touch down as slowly as possible, keep the aileron
deflection in for a crosswind, raise the flaps to put the weight on
the wheels and have a minimum of exposure as you slow to taxiing
speed. (Yeah, I know the FAA doesn't like touching the flaps on
rollout, but on a fixed gear airplane, it isn't going to cause the
gear to fold and it raises the level of safety on rollout.)
The NTSB has been pointing it out for years, the landing accident data
continues to show the number of accidents due to excess speed at
touchdown and loss of directional control on rollout or going off the
end of the runway. Yet pilots keep landing fast because it "feels"
better and then being surprised because they lose control of the
airplane during rollout.
It's sad how we keep drawing the wrong conclusions and perpetuating
myths to new pilots such as this gentleman.
I know you fly a Maule, however, the same data applies to tailwheel as
to nosewheel airplanes. The high speed, wheel landing in a tailwheel
airplane may allow a pilot keep it over the runway in the crosswind,
but he still has to slow down and lower the tail, and it's that
process that bites so very many and partially why we pay such sky
high insurance on tailwheel airplanes.
All the best,
Rick
"G.R. Patterson III" <grpp...@comcast.net> wrote in message news:<3ED229F8...@comcast.net>...
EDR
Drescher <GLDre...@deja.com> wrote:
Ground speed at 60 kts indicated airspeed/no-wind is the same as 85 kts
indicated airspeed/+25 kts headwind.
At 60 kts indicated airspeed/0 kts headwind/30 deg flaps you will land
straight ahead with a stall speed of 38kts.
At 90 kts indicated airspeed/+25 kts headwind/0 deg flaps you will land
straight ahead with a stall speed 45 kts.
Using the old rule of thumb of and additional 100 feet for every 1 kt
increase in approach airspeed, one could surmise that an addtional 500
feet would be required for ground roll. Practicle experience, however,
will require less. The higher stall speed will put the weight on the
wheels sooner so that braking will become effective earlier in the
roll. The more flaps used, the lower the stall speed, the greater the
float in ground effect. With the steady +25 headwind the stall speeds
effectively become 13kts (38) and 20 kts (45-25)
downwind: 1.5 Vso / 1.5 * 38 = 57
base: 1.4 Vso / 1.4 * 38 = 53
final: 1.3 Vso / 1.3 * 38 = 50
downwind: 1.5 Vso / 1.5 * 45 = 68
base: 1.4 Vso / 1.4 * 45 = 63
final: 1.3 Vso / 1.3 * 45 = 59
EDR
> speed gives you LESS control. The vast majority of landing crashes
> involve touchdowns at high speed and loss of control or running out of
> runway. You have the best control of the aircraft by touching down
> as slowly as possible. The aerodynamic controls are still fully
> effective (but you have to be willing to use them and most pilots
> aren't) and you are slowed to a point where you actually have rolling
> control.
In the case of a headwind, yes.
In the case of a crosswind, where you have run out of aileron and
rudder and are drifting with the wind, the extra speed will allow you
to track straight without drift.
Julian Scarfe
> news:JAnAa.12846$Mu3.2...@newsfep4-glfd.server.ntli.net...
> > With a hypothetical perfectly steady strong wind, there would be no
point
> > in reducing flap setting.
"Peter Duniho" <NpOeS...@NnOwSlPiAnMk.com> wrote in message
news:vd4o03q...@corp.supernews.com...
>
> Not strictly true.
>
> One of the effects of a strong headwind is to steepen the descent angle,
all
> else being equal. Since flaps also steepen the descent angle, a pilot
> wishing to fly a consistent approach may find that making the approach
with
> reduced flaps allows them to maintain a similar descent angle that they
> would find in a no-wind approach, without a need for greatly increased
> power.
I'm not sure I agree, Pete, at least not with the rationale. If you make
powered approaches, I don't think it matters too much how much power you use
in a light aircraft, as there's usually plenty of excess. After all, you
can always "save a little power" by increasing glide angle.
Julian
Julian Scarfe
news:d9fecbe.03052...@posting.google.com...
> For some reason pilots like to land fast. And we keep werecking
> airplanes because of it. The exposure is during decleration to taxi
> speed from touchdown speed. The faster you touch down, the longer
> the period of exposure and the more likely a pilot is to lose
> control. Touch down as slowly as possible, keep the aileron
> deflection in for a crosswind, raise the flaps to put the weight on
> the wheels and have a minimum of exposure as you slow to taxiing
> speed.
I agree with the underlying message (that pilots tend to land too fast for
no reason), but I think you miss the principle which may have merit. It
comes down to the same reason you want to raise the flaps asap after
touchdown. At a particular airspeed during the deceleration you have the
same or greater lateral control authority without flap but you have less
lift without flap than with flap. That means the tyres can do more to help
with lateral control. The effect may be small, but it's there.
Julian Scarfe
Roger Halstead
Sarangan) wrote:
>super...@hotmail.com (Koopas Ly) wrote in message news:<c94c7949.03052...@posting.google.com>...
>> Hello everyone,
>>
>> My CFI told me to use a maximum of 20 deg. flaps on approach in strong
>> winds, in a 172SP. Why would you reduce the flap setting in strong
>> winds when landing? What would you quantify as "strong" winds?
>
>Anything that approaches the maximum demonstrated crosswind can be
>considered as strong wind. Of course, this is an arbitrary definition.
>In strong cross winds, a faster landing speed will help maintain
>directional control by giving more rudder authority. This is why less
>flaps is generally recommended.
>
Only in gusty winds do I land faster.
EVERYONE should use the POH figures and not what one of us thinks is
better. That "little extra" has gotten many a pilot into trouble.
The FAA Wings Program has addressed that issue a number of times. It
is a big enough problem that the FAA even sent out a letter addressing
the issue some years back. All things being equal, "Landing faster
is not normally safer". On the contrary, even a little extra is
considered dangerous if it's not recommended by the POH..
Even in 150s and 172s I've never found it to be necessary to add speed
except for gusty conditions. Certainly in gusty conditions, carry
"half the gust component". Again, stick with the POH which, except for
older planes should have all these figures.
As with flaps...stick with the POH which usually says "as needed".
For a while the FAA was quite adamant about "If you got 'em, use 'em".
They are no longer quite so adamant, but I've never found full flaps
to hinder. I'm not recommending some one who only uses 20 degrees go
out and start using full flaps for all landings. Like any other
change it takes practice to get used tot he changes.
Strong winds is a relative statement.
To a student, or any pilot who has not been flying much even an 8 knot
cross wind can seem like a lot. To the more experienced (and
*proficient*, not just current) they will be usually well beyond the
demonstrated cross wind component for that plane.
Some aircraft with remarkable cross wind capability have quite low
demonstrated cross wind components. The Bonanza is one. My Deb had a
demonstrated cross wind component of 12 knots. It will handle anything
up to 25 as can I "When I am well practiced and proficient". That is
not the case right now. I haven't been flying near enough to tackle a
25 knot cross wind component, but I'm very comfortable with 15. So,
those are my daily adjustable limits.
A few hours practice and I'll be back where I was.
AND I'm headed for the airport. <:-))
I spend hours practicing maneuvers. I spend lots of time flying in
cross winds and gusty winds to stay sharp. I'm very conservative in
what I tackle, but aggressive in what I practice. I stay within the
limits of the plane, the certificate, and myself. I also practice
right out to those limits.
Some pilots can fly 25 hours a year and stay sharp. I don't know how
and I sometimes doubt. I do know it takes me more than 25 hours to
stay proficient. The thing is, I can see when my skills are starting
to get a bit rusty. I know what I need to go out and practice. I also
fly with an instructor every few months to make certain I'm not
picking up any bad habits. However there is one thing that none of us
can recognize and that is loss of judgmental skills. Hence a very
good reason for flying with an instructor every few months. (and hope
you don't get one whose personality, or teaching style clash with
yours)
All that helps, but nothing can replace hours of flying and practice.
Roger Halstead (K8RI EN73 & ARRL Life Member)
www.rogerhalstead.com
N833R World's oldest Debonair? (S# CD-2)
>
>>
>> Similarly, why would you fly a higher approach speed in GUSTING winds?
>> Is it because GUSTING winds can cause airspeed fluctuations, which
>> may lead to unexpected loss of lift, increased sink rate that
>> translates into a steeper descent? Note that I've only mentioned
>> gusting winds effects. "Steady" winds effects should only cause
>> changes in groundspeed that would lead the airplane to land short or
>> long of the runway should the pilot not take corrective action.
>> However, the airplane would still be controllable. On the other hand,
>> I take it that you'd increase your speed to offset gusting *TAILWINDS*
>> that can cause abrupt 1/ changes in the direction and speed of the
>> airmass and most importantly 2/ a sudden decrease in indicated
>> airspeed, which *could* lead to loss of control of the aircraft? Or
>> perhaps increasing your speed somehow makes the airplane generally
>> "more stable" [very open to interpretation]. Speaking of
>> controllability, I guess one wouldn't be so worried with gusting
>> *headwinds* since they would just result a quick boost of extra lift
>> and ballooning (which can really screw up an approach but not as much
>> as being sunk into the ground by tailwinds)
>
>Gust implies a sudden change in wind speed or direction. If the wind
>is 10G20, you could potentially lose or gain 10 knots of airspeed.
>Since losing 10 knots is more hazardous than gaining 10 knots, we add
>5 knots to the approach speed. Now, a 10 knot gust will can put us 5
>knots too slow, or 15 knots too fast. The theory is that, the 15 knots
>of excess speed is offset by the steady portion of the headwind. On
>the other hand, if the wind is 0G10, then you have a real problem
>because 15 knots too fast can make you go off the runway.
>
>
>
>>
>> Are gusting winds and windshear synonymous? As I understand,
>> windshear is the sudden change in wind speed and direction. However,
>> gusting winds given by say ATIS will still follow the wind direction
>> and speed. I would fear gusting winds as much as windshear, IMO.
>
>Windshear is a change in wind speed or direction as a function of
>altitude. Wind gust is a change in wind speed or direction as a
>function of time at the same altitude (generally ground level).
>
>Wind shear is encountered as you descend on one moving airmass into
>another.
>
>The effects of wind shear and wind gusts are the same. They result in
>a loss or gain of airspeed.
>
>
>>
>> Do you use the rule "add half the gust wind speed to your approach
>> speed"? What about landing in strong winds with no gusts? In such
>> case, would you still up your approach speed?
>>
>
>Generally, there is no need to add gust factor if there is no gust.
>However, you can expect wind gusts any time there is strong winds.
>
>>
>> An inquisitive Alex.
Roger Halstead
I think the above was stated with a bit of scarcasem...I hope.
You do not add any speed for a steady head wind. That is a dangerous
practice. Add speed only for gusty wind.
If you have a 25 knot head wind gusting to 35 that is a 10 knot gust
component.
Add half the 10 knots to your NORMAL speed on final.
Hopefully your normal final is what the POH says it should be<:-))
Roger Halstead
wrote:
>Assuming that you are landing into the wind ...
>
>With a strong wind condition, you can maintain a higher airspeed and have
>your ground speed remain reasonable. At this higher airspeed, flaps are not
There is no need to maintain the higher airspeed. Why do so if it's
not necessary?
Remember as a "rule of thumb" using %. Your landing distance
increases at twice the rate of the air speed increase.
IE. For a 30% increase in airspeed it takes 60% longer to land.
Subtract from that the steady state head wind and you will find that
adding the wind speed to your landing speed will increase you landing
distance.
Say your normal landing speed is 60 and you add 25 knots for the wind.
That is a 41 % increase which should add 84 % to the landing distance,
but we have to subtract the head wind from the ground speed.
OK, ...If you plane takes 1500 feet to land the 25 knots will increase
that to 2200 feet, but you will be setting down on the runway 25 knots
slower. so the roll out will be shorter (once you get down). In this
case "I believe" (if I did the math right) it would be half of the 84%
so it would take you 2130 feet to land.
Your landing distance increases basically at twice the rate the wind
would shorten it if you add the wind speed to your airspeed.
Man, but that sounds convoluted.
Just stick with the POH speeds it's easier, safer, easier on the
aircraft, and gives shorter landing distances.
Roger Halstead
wrote:
>Alex,
<snip>
>
> Very, very few accidents occur because the pilot had
>control difficulties on final in a gusty crosswind. A lot occur
>because he landed fast, with partial flaps, and then ran off the
>runway and hit something.
>
Very well put.
Roger Halstead (K8RI EN73 & ARRL Life Member)
www.rogerhalstead.com
N833R World's oldest Debonair? (S# CD-2)
>All the best,
>Rick
<snip>
Rick Durden
>>All the steady and half the gust.<<
Good lord no. Only add half the gust factor. Do NOT add anything for
the steady wind component. The most common cause of landing accidents
is too much speed on final.
All the best,
Rick
EDR <er...@rrohio.com> wrote in message news:<260520031007396008%er...@rrohio.com>...
> > My CFI told me to use a maximum of 20 deg. flaps on approach in strong
> > winds, in a 172SP.
> > Why would you reduce the flap setting in strong winds when landing?
>
> To reduce drift. The more flaps you have hanging out, the slower your
> stall speed, the greater effect the wind will have on pushing your
> aircraft in the direction of flow.
>
> > What would you quantify as "strong" winds?
>
> I would say anything greater than the demonstrated crosswind speed,
> regardless of whether it is a direct headwind or direct crosswind.
>
> > Similarly, why would you fly a higher approach speed in GUSTING winds?
>
> > Is it because GUSTING winds can cause airspeed fluctuations, which
> > may lead to unexpected loss of lift, increased sink rate that
> > translates into a steeper descent?
>
> Yes, and no. A higher sink rate does not necessarily mean your angle of
> attack will change.
>
> > Are gusting winds and windshear synonymous?
>
> Not necessarily. Wind shear is a sudden change in direction of (I
> think) 30 degrees or more.
>
> > Do you use the rule "add half the gust wind speed to your approach
> > speed"?
>
> All the steady and half the gust.
>
> > What about landing in strong winds with no gusts? In such case,
> > would you still up your approach speed?
>
> Depends. How long is your runway? What obstacles do you have to clear
> to get to the threshhold? Are you going to use less than full flaps?
Rick Durden
Excellent response, you broke the code.
The flaps were put on the airplane for a reason, and using them, all
of them, helps reduce landing accidents substantially.
All the best,
Rick
David Megginson
> You do not add any speed for a steady head wind. That is a dangerous
> practice. Add speed only for gusty wind.
I guess this distinction has to do with where you fly. In central
Canada, over my first year and a bit of flying, I'm having trouble
remember ever experiencing a steady surface wind over 10-12 knots --
maybe if I were flying on the open praries or by the ocean, a wind
like that would be more likely. Anything above light winds seems
always to mean gusts and low-level turbulence here.
Rick Durden
> In the case of a headwind, yes.
> In the case of a crosswind, where you have run out of aileron and
> rudder and are drifting with the wind, the extra speed will allow you
> to track straight without drift.
That is not correct at all. If you have run out of aileron or rudder,
land on another runway or on a taxiway into the wind. At some point
you have to slow down. Adding speed on final merely allows you to
keep the airplane from drifting prior to touchdown. However, you do
not yet have rolling control and if you cannot keep it from drifting
at your approach speed, then you may not be able to do so after you
have touched down and are decelerating to that approach speed. That
deceleration time on the ground, as the flying controls lose
effectiveness and rolling control is not yet effective is where pilots
lose it and wreck airplanes. The accident data is pretty clear, the
slower you touch down, the less the chance of an accident in a
crosswind.
All the best,
Rick
Rick Durden
I understand what you are saying, however, you still need to touch
down as slowly as possible to take advantage of the lateral holding
ability of the tires (which lessens as the speed increases and the
weight is on the wings).
All the best,
Rick
"Julian Scarfe" <jul...@avbrief.com> wrote in message news:<uiwAa.13229$Mu3.2...@newsfep4-glfd.server.ntli.net>...
G.R. Patterson III
Rick Durden wrote:
>
> I know you fly a Maule, however, the same data applies to tailwheel as
> to nosewheel airplanes. The high speed, wheel landing in a tailwheel
> airplane may allow a pilot keep it over the runway in the crosswind,
> but he still has to slow down and lower the tail, and it's that
> process that bites so very many and partially why we pay such sky
> high insurance on tailwheel airplanes.
No, I slow down in the air and touch down in a three-point attitude,
though in a crosswind, it's actually upwind main and tailwheel. I need
the extra speed and propwash for rudder authority, of which the Maule
is lacking. This, by the way, is straight out of the POH.
TheMadTexan
constant.
If you have a headwind, you can increase your indicated airspeed and land in
the same distance, because your groundspeed is unchanged. You gain control
surface efectiveness and use the same amount of runway. It's no harder on
the airplane, because your touchdown groundspeed hasn't changed.
"Roger Halstead" <rdha...@tm.net> wrote in message
news:8555dvoqp55ple5kj...@4ax.com...
Koopas Ly
Thanks for the voracious responses and [differing] opinions. :/ I can
see that people have a lot of free time on this Memorial day. That's
what I call time well spent :)
Rick, I've got some additional questions below in response to your
reply.
Thanks all,
Alex
rdu...@compuserve.com (Rick Durden) wrote in message news:<d9fecbe.03052...@posting.google.com>...
> Alex,
>
> Your instructor is correct in adding some speed in gusting winds,
> although the most common error is to add too much...and too fast on
> final is the cause of a very high proportion of landing accidents.
> Add half the gust factor. If the wind is at 10, gusting to 20, the
> gust factor is 10, so add 5 to your normal approach speed.
Do you define the gust factor as half of the gust wind speed? And
then take half of that and add it to your approach speed?
I originally thought you'd just add half of your gust. So if you got
winds at 13010G18, you'd up your approach speed by 9 kts. You're
saying that your gust factor is half of 18, and that you would only
add half of that (half of 9 knots) to your approach speed?
> The problem when a gust end your airspeed drops.
What did you mean by that?
> Fortunately, in light
> airplanes such as we fly, it's not a big problem as it can be in
> larger aircraft and jets, so it is not necessary to add much speed.
>
> Where you instructor is incorrect is in having you reduce the flap
> being used. If he goes into NTSB accident reports on landing
> accidents he'll find that as flap deflection decreases the number of
> landing accidents increases. The reason is that the problem pilots
> perceive is not the true risk they face. Pilots get worried about
> controlling the airplane when they fly final, so they add speed and
> reduce flaps for "more control". The reality is that they have plenty
> of control at the normal approach speed with full flaps. The problem
> comes when they touch down fast, with partial flaps, because they are
> far more likely to lose control during rollout or go off the end of
> the runway. Very, very few accidents occur because the pilot had
> control difficulties on final in a gusty crosswind. A lot occur
> because he landed fast, with partial flaps, and then ran off the
> runway and hit something.
So you're recommending full flaps each time at landing regardless of
wind conditions? There's been a lot of debate on the newsgroup about
proper flap setting when landing with gusts. Going back to flap
usage, the main purpose I use flaps is to reduce stall speed and
steepen flight path angle. Referring to my 172SP POH, if my landing
speed is 1.3xVso, the reduced stall speed means that I can land at 52
kts. with full flaps versus 62 kts (no flaps). Note that if I were to
use 20 deg. of flaps, my stall speed is 41 kts. IAS and thus, the
landing speed 53 kts. That's only a 1-knot increase in landing speed
for 10 degrees of flaps.
Therefore, if I have to land faster as in your scenario above by an
additional 5 kts, I would be more prone to use 20 degrees of flaps
since:
1/ It would still allow me to land slow (only 1 knot faster than the
full 30-deg. flap configuration.)
2/ I would experience much less drag at 20-deg. vs. full flap setting.
As a result, I could use a lower power setting even though I do
realize most airplanes have plenty of excess power.
Wouldn't 20 degrees of flaps make sense in gusting wind conditions? I
concur with your adamancy regarding landing at the slowest speed
possible: the NTSB has numerous accident reports concerning excessive
airspeed during approach and landing (i.e. Southwest Flt. 1455 in
Burbank).
Some folks did bring up the point of increased control effectiveness
with higher airspeeds in high crosswind situations, which you don't
find merit in. Why not?
The issue of decreased roll effectiveness with full flaps was also
discussed. Your position is that it's not an issue?
Last, I get the impression that pilots here don't land with full flaps
in gusty conditions because the extra drag hinders with landing faster
in such conditions. You seem to promote landing faster in gusty wind
conditions but at the same time recommend using full flaps to allow
for the slowest touchdown speed. If you plan on touching down 5 knots
above the slowest landing speed with full flaps, why bother going full
flaps then? It seems to defeat the purpose. Might as well put in a
little less flaps and save a bit on power. But I may have
misinterpreted you.
Thanks for responding,
Alex
>
> All the best,
> Rick
>
> super...@hotmail.com (Koopas Ly) wrote in message news:<c94c7949.03052...@posting.google.com>...
> > Hello everyone,
> >
> > My CFI told me to use a maximum of 20 deg. flaps on approach in strong
> > winds, in a 172SP. Why would you reduce the flap setting in strong
> > winds when landing? What would you quantify as "strong" winds?
> >
> > Similarly, why would you fly a higher approach speed in GUSTING winds?
> > Is it because GUSTING winds can cause airspeed fluctuations, which
> > may lead to unexpected loss of lift, increased sink rate that
> > translates into a steeper descent? Note that I've only mentioned
> > gusting winds effects. "Steady" winds effects should only cause
> > changes in groundspeed that would lead the airplane to land short or
> > long of the runway should the pilot not take corrective action.
> > However, the airplane would still be controllable. On the other hand,
> > I take it that you'd increase your speed to offset gusting *TAILWINDS*
> > that can cause abrupt 1/ changes in the direction and speed of the
> > airmass and most importantly 2/ a sudden decrease in indicated
> > airspeed, which *could* lead to loss of control of the aircraft? Or
> > perhaps increasing your speed somehow makes the airplane generally
> > "more stable" [very open to interpretation]. Speaking of
> > controllability, I guess one wouldn't be so worried with gusting
> > *headwinds* since they would just result a quick boost of extra lift
> > and ballooning (which can really screw up an approach but not as much
> > as being sunk into the ground by tailwinds)
> >
> > Are gusting winds and windshear synonymous? As I understand,
> > windshear is the sudden change in wind speed and direction. However,
> > gusting winds given by say ATIS will still follow the wind direction
> > and speed. I would fear gusting winds as much as windshear, IMO.
> >
> > Do you use the rule "add half the gust wind speed to your approach
> > speed"? What about landing in strong winds with no gusts? In such
> > case, would you still up your approach speed?
> >
> >
> > An inquisitive Alex.
Julian Scarfe
>
> I understand what you are saying, however, you still need to touch
> down as slowly as possible to take advantage of the lateral holding
> ability of the tires (which lessens as the speed increases and the
> weight is on the wings).
But for a given speed that "lateral holding ability" lessens markedly with
flap setting.
Take an absurd, extreme case. Imagine I could take a conventional light
aircraft that usually stalls at 50 knots and give it flaps that allow it to
stall at 20 knots. How would that be to land to land in a strong crosswind?
Pretty tough. The problem is that by the time you get it down to the 20
knots needed to make it stop flying, you have very little rudder authority.
At 25 knots, you're still in the air, with no help from the tyres, but you
don't have the lateral control available to keep it where you want it. Even
at 15 knots you'd be generating a large amounts of lift which would hinder
the lateral holding ability of the tyres until you got the flaps up. It's
doubtless true that your time of exposure is shorter than if you're touching
down at 50, but that doesn't help if for that shorter exposure time you
cannot control the aircraft. This also doesn't take into account the
aerodynamic interaction between flaps and aileron, which tends to reduce the
authority of the ailerons with flap extended.
In real life, the difference is not as pronounced, but the effect works the
same way. Maybe you get 10% more rudder authority at touchdown with a lower
flap setting. What's that worth compared with the extra landing distance
and time at higher speed that comes from a lower flap setting? It all
depends. I think it would be absurd to reduce flap for a 10 knot xwind on a
2000 ft runway, but give me a 5000 ft runway and a xwind of 15 gusting to 25
knots and I think I'll take the extra control authority.
Clearly the magnitude of the effect is dependent on the aircraft. For some
aircraft less than full flap may *never* be necessary. My PA30 POH calls
for "judicious use of flap in turbulence and crosswinds", whatever that
means!
I'm sure you're correct that more pilots get into trouble from using higher
speeds and lower flap settings than the converse. But if pilots understand
the effects involved, they can make appropriate decisions rather than
depending on rote.
Julian Scarfe
Peter Duniho
> I'm not sure I agree, Pete, at least not with the rationale. If you make
> powered approaches, I don't think it matters too much how much power you
use
> in a light aircraft, as there's usually plenty of excess. After all, you
> can always "save a little power" by increasing glide angle.
The point is that you can use the same power setting you used before.
Granted, now you're changing the flap setting instead. It's impossible to
fly the exact same approach if the wind conditions are different. But it IS
a valid reason to select reduced flaps in a constant headwind.
Further, consider the no power case, which is how many pilots fly the
descending portion of the pattern, airplane and traffic conditions
permitting. To fly a similar pattern, one MUST reduce the descent angle,
and if you want to always fly a no power approach, the only other way to
accomplish that is to use a reduced flap setting.
Pete
Cub Driver
>Similarly, why would you fly a higher approach speed in GUSTING winds?
Well, it feels better, for a start.
I assume the problem with gusting winds is that if you fly at no-wind
speed, not far above the stall, you might find yourself perilously
close to stall if windshear put you into a bank or otherwise upset the
aircraft.
Similarly, if you land with a bounce, you put on some power so as to
stabilize the aircraft; you don't just sit there and wait for it to
hit the ground again.
all the best -- Dan Ford (email: web AT danford.net)
see the Warbird's Forum at http://www.danford.net/index.htm
Vietnam | Flying Tigers | Pacific War | Brewster Buffalo | Piper Cub
Roger Halstead
<da...@megginson.com> wrote:
>Roger Halstead <rdha...@tm.net> writes:
>
>> You do not add any speed for a steady head wind. That is a dangerous
>> practice. Add speed only for gusty wind.
>
>I guess this distinction has to do with where you fly. In central
>Canada, over my first year and a bit of flying, I'm having trouble
>remember ever experiencing a steady surface wind over 10-12 knots --
I agree that often strong winds are not steady state winds.
It varies a lot, but the reference was to adding air speed to
compensate for strong head winds that were not gusting.
Some time back I took off with winds 30 G 50. I added 10 knots for
half of the gust factor which was 20 more than the steady state of 30.
If the winds are even 40 G 50 you'd still only add 5 knots.
Course many pilots would elect to stay home under those conditions and
justifiably so. Both the pilot and aircraft need to be capable of
handling those winds.
>maybe if I were flying on the open praries or by the ocean, a wind
>like that would be more likely. Anything above light winds seems
>always to mean gusts and low-level turbulence here.
A lot depends on the terrain. HTL which is about 50 miles north of
here has a 09/27 runway. A couple hundred yards to the north and
paralleling the whole length of the runway is a tree line. When out
of the north the wind spills over those trees and down across the
runway, hits a small ridge and rolls back. You can often expect to
find the wind making 3, 180 degree changes along with some nasty
rolling winds.
It's a great place for those who think they are all set for cross
winds. <:-))
Roger Halstead (K8RI EN73 & ARRL Life Member)
www.rogerhalstead.com
N833R World's oldest Debonair? (S# CD-2)
>
>
>All the best,
>
>
>David
EDR
Keep in mind that you only add enough power to maintain track. This may
be only 5 kts, not really that significant.
If you only have one runway available within 50 miles, you may not
really have a choice in going somewhere else. Even the other runway
available may not be any closer to wind direction.
I checked my library (Takeoffs and Landings, Collins; Stick and Rudder,
Langewiesche; Advanced Pilot's Flight Manual, Kirchner; Aerodynamics
for Naval Aviators) and found recommendations for adding 5 kts for
steady and half the gust.
I know I have seen in print the "all the steady and half the gust" that
I posted earlier, but cannot find it. Perhaps it is jus an OWT. I stand
corrected.
G.R. Patterson III
Rick Durden wrote:
>
> The NTSB has been pointing it out for years, the landing accident data
> continues to show the number of accidents due to excess speed at
> touchdown and loss of directional control on rollout or going off the
> end of the runway. Yet pilots keep landing fast because it "feels"
> better and then being surprised because they lose control of the
> airplane during rollout.
Pilots keep landing fast because it works. Landing in high winds is
inherently dangerous. If pilots didn't pad the speed to compensate, there
still would be lots of accidents, and the NTSB would be screaming about
the number of accidents "caused" by NOT carrying extra speed during windy
conditions.
Roger Tracy
a crosswind and just have never been comfortable with that. In my
Tiger I find that the extra speed just makes the plane skittish while
transitioning from the wings to the tires supporting the weight. It seems
to me I'd be MORE likely to lose control at the higher touchdown speed.
I still want to touch down as slow as possible.
Flyer22A
>
> >>Using less flaps gives you a higher airspeed. This gives the
> controls more
> authority. It also puts you on the ground at a higher speed, which
> gives you
> more control.<<
>
> Sadly, a common misconception. Putting you on the ground at greater
> speed gives you LESS control. The vast majority of landing crashes
> involve touchdowns at high speed and loss of control or running out of
> runway. You have the best control of the aircraft by touching down
> as slowly as possible. The aerodynamic controls are still fully
> effective (but you have to be willing to use them and most pilots
> aren't) and you are slowed to a point where you actually have rolling
> control.
Exactly right on.
> For some reason pilots like to land fast. And we keep werecking
> airplanes because of it. The exposure is during decleration to taxi
> speed from touchdown speed. The faster you touch down, the longer
> the period of exposure and the more likely a pilot is to lose
> control. Touch down as slowly as possible, keep the aileron
> deflection in for a crosswind, raise the flaps to put the weight on
> the wheels and have a minimum of exposure as you slow to taxiing
> speed. (Yeah, I know the FAA doesn't like touching the flaps on
> rollout, but on a fixed gear airplane, it isn't going to cause the
> gear to fold and it raises the level of safety on rollout.)
Right again. All of the (small) aircraft I have ever seen were designed
to fly, not careen down the runway at high speed.
> The NTSB has been pointing it out for years, the landing accident data
> continues to show the number of accidents due to excess speed at
> touchdown and loss of directional control on rollout or going off the
> end of the runway. Yet pilots keep landing fast because it "feels"
> better and then being surprised because they lose control of the
> airplane during rollout.
>
> It's sad how we keep drawing the wrong conclusions and perpetuating
> myths to new pilots such as this gentleman.
>
> I know you fly a Maule, however, the same data applies to tailwheel as
> to nosewheel airplanes. The high speed, wheel landing in a tailwheel
> airplane may allow a pilot keep it over the runway in the crosswind,
> but he still has to slow down and lower the tail, and it's that
> process that bites so very many and partially why we pay such sky
> high insurance on tailwheel airplanes.
This is true too. Flying my C-140 for years I occasionally encountered
the "mysterious" gust of wind (that seems to upend so many novice
tail wheel pilots) and simply flew the airplane through it, never
ending up with the wheels pointing up. I only ever did about 3
wheel landings, what was the point? Slow 3 point landings work just
fine if one continues to fly the AC to the end.
Flyer22A
Or turn?
Isn't that what the crosswind component is all about?
"EDR" <er...@rrohio.com> wrote in message
news:260520031620142479%er...@rrohio.com...
EDR
<pilo...@yahoo.com> wrote:
> If this were true, how would one ever slow down enough to stop?
You are only adding enough power to hold the track.
> Or turn?
As you are asking the question, it would seem you have never flown in
such conditions. In a high crosswind, you are cross controlled (rudder
and aileron opposite directions). When you apply rudder and aileron in
the same direction, you turn (just like you normally would, although A
LOT faster in one direction than the other!)
> Isn't that what the crosswind component is all about?
Isn't "what" what crosswind component all about? Turning?
In a crosswind you either "crab" or "slip" into the wind. In a crab you
turn in the direction of the crosswind until your track is aligned with
the desired direction of flight. You still have to apply cross-control
(slip) prior to touching down to avoid shearing the landing gear with
side-load.
In a slip, you cross-control, upwind wing down (roll) and use opposite
rudder to maintain the desired direction of flight. The most important
thing to remember with the slipping method is not to get to slow, least
you experience and accellerated stall.
Doug
I have successfully wheel landed my Aviat Husky taildragger in some
pretty stiff crosswinds. Higher speed does indeed give me more rudder
control. True, I then do have to get the tail down. But I can use the
gyroscopic stability of the wheels turning and the BRAKES if necessary if I
run out of rudder. Also, it is much easier to do a go around if I run out of
rudder upon touchdown, and have to go around before I get the tail down. By
wheel landing at higher speed, I can do one thing at a time. Upwind
mainwheel down, other mainwheel down, then tail down, as opposed to having
to do it all at once, at stall speed, by putting all three down at once.
The only disadvantage is it does eat up runway, but the Husky usually has
plenty, as it lands so short anyway.
Also, by landing with power, I can wait for a lull in the gusts and cut the
power. I can choose the when I want to land, when I want to put the tail
down, with ME flying the plane as opposed to the plane flying me.
There are some who worship at the holy grail of three point landings in a
tailwheel aircraft and there are wheel landing advocates, like me. And don't
get me started on why wheel landings are better for rocky fields or this
will go on forever. (Has to do with rocks being thrown up and dinging the
bottom of the horizontal stabilizer).
"Rick Durden" <rdu...@compuserve.com> wrote>
Roger Halstead
<grpp...@comcast.net> wrote:
>
>
>Rick Durden wrote:
>>
>> The NTSB has been pointing it out for years, the landing accident data
>> continues to show the number of accidents due to excess speed at
>> touchdown and loss of directional control on rollout or going off the
>> end of the runway. Yet pilots keep landing fast because it "feels"
>> better and then being surprised because they lose control of the
>> airplane during rollout.
>
>Pilots keep landing fast because it works. Landing in high winds is
>inherently dangerous. If pilots didn't pad the speed to compensate, there
>still would be lots of accidents, and the NTSB would be screaming about
>the number of accidents "caused" by NOT carrying extra speed during windy
>conditions.
>
We had a DE in the area who used to say, any one could fly an airplane
on, but it took a pilot to land one.
Landing fast is easier which ain't all bad. That's not to say it's
safer. The transition from flying to where the wind is no longer a
factor takes longer when you come in faster. So the wind acts on the
plane longer.
I sometimes wonder if what we do out of instinct isn't always the best
way to go. Certainly flying the normal speed in gusty winds isn't
instinctual. If the book says half the gust factor, we all get the
feeling that if a little extra is good, then a little more is even
better.
.
When it comes to steady state winds, my instructors (whyyyy back when)
made certain I flew the same speeds as normal. They were real
sticklers about only adding half the gust factor. They were also very
adamant about doing a good portion of the pattern at idle which meant
I had to learn to read the winds.
If we had a good strong head wind, then I was expected to keep my base
in closer and still glide to a landing at a specific spot. True, with
a strong wind the angle of descent was steeper, but the roll out sure
was short.
Whether I used full or partial flaps was a subject that never came
up...The Colt didn't have any. Slips came very early on in the
training. <:-))
The one concession I make to the winds is I quit making full stall
landings. When you are sitting there, nose way high with the wheels
ready to kiss the pavement the moment the stall breaks, a sudden gust
of wind can be really embarrassing. (been there and done that)<sigh>
Roger Halstead (K8RI EN73 & ARRL Life Member)
www.rogerhalstead.com
N833R World's oldest Debonair? (S# CD-2)
Greg Esres
flap setting. >>
A touch of power does wonders for rudder authority. (SE piston,
anyway.)
<<I think it would be absurd to reduce flap for a 10 knot xwind on a>>
But lots of pilots and instructors do just that.
Rick Durden
You mentioned rote at the end of your message. That's the majority of
the problem. Pilots depend on rote memory, and, when under pressure,
revert to early learning. As a result, the rote of partial flaps and
high speed, without much aileron deflection at and after touchdown
means that we have lots of crumpled aluminum and high insurance
premiums. If pilots would simply fly at the published approach
speeds, plus half the gust factor, use all the flaps available and
crank in full aileron deflection on touchdown, we'd all be paying
less for insurance.
All the best,
Rick
"Julian Scarfe" <jul...@avbrief.com> wrote in message news:<%pEAa.13414$Mu3.2...@newsfep4-glfd.server.ntli.net>...
Rick Durden
Yes, the gust factor is the amount of the max gust reported above the
steady state wind. You add NO speed for a steady state wind...there
is no reason to do so. Published approach speed is already 1.3 times
stall speed and provides plenty of control authority and the
ability to flare power off...adding speed only means float, which
causes directional control problems or landing on the nose gear, which
can be very ugly. Add one half of gust factor.
When a gust ends the effect on the airplane is to lose airspeed by the
amount of the gust. Because we fly little airplanes that accelerate
relatively well in such circumstances, even with full flaps,
particularly because simply adding a little power puts airflow from
the prop over the wings, the airspeed loss is no big deal. Adding
extra speed is much more of a problem.
No, you don't want just lift flaps. You need the drag to help you
decelerate and to stop the airplane from floating. Floating when you
flare is what starts the whole process of loss of control. You've
been keeping the airplane straight on the approach, so flare and plant
it before you lose control. That means max drag in the flare. By
closing the throttle you get the drag from the prop. With flaps, that
means you don't float if you are on speed. On touchdown you crank in
all the rest of the aileron deflection to take advantage of adverse
aileron yaw to assist with directional control and keep the weight on
the upwind tire and you use to flaps to help declerate as fast
as possible to a speed where you have rolling control. Deceleration
in the first third of the landing roll is mainly aerodynamic as the
tires aren't really gripping yet (there is experimental data on that
from hydroplaning studies). Then, get the flaps up to dump the lift
and get the weight on the wheels for rolling and braking control.
For a longer discussion of this subject, go to
www.avweb.com/news/columns/182656-1.html
G.R. Patterson III
Roger Halstead wrote:
>
> The transition from flying to where the wind is no longer a
> factor takes longer when you come in faster.
No, it doesn't. If I'm doing a full flaps landing (not a short field landing),
I'll be at 65 mph on short final, and I will touch down at 45. If I'm coming
in with no flaps, I'll be doing 80 mph and touch down at 60. Once I'm on the
ground, the wind will cease to be much of a factor by the time I've lost
about 15 mph in either configuration. It's also tons of fun to try to get
the flaps up in a Maule doing 40 mph in a gusting crosswind without tangling
with the runway lighting system.
Thomas Borchert
> But for a given speed that "lateral holding ability" lessens markedly with
> flap setting.
>
I don't know. Most GA aircraft have flaps that will increase drag only
beyond 20 degress, not lift.
--
Thomas Borchert (EDDH)
Thomas Borchert
> I would experience much less drag at 20-deg. vs. full flap setting.
>
As the discusion regarding tire traction here showed, you want all of
that dragonce on the ground.
What Rick is saying, IMHO, is that you have plenty of control
effectiveness at lower speeds IF you use the controls to the full
extent. If that doesn't work, the crosswind is simply too strong to be
able to land safely. You may still have to if you put yourself into
that kind of situation, but it won't be safe.
--
Thomas Borchert (EDDH)
Rick Durden
This is really weird. I answered your post and my answer
disappeared. I must not know the secret handshake.
In a nutshell, take a look at www.avweb.com/news/columns/182656-1.html
for a more involved discussion of the matter.
All the best,
rick
john smith
> I'll be at 65 mph on short final, and I will touch down at 45. If I'm coming
> in with no flaps, I'll be doing 80 mph and touch down at 60. Once I'm on the
> ground, the wind will cease to be much of a factor by the time I've lost
> about 15 mph in either configuration. It's also tons of fun to try to get
> the flaps up in a Maule doing 40 mph in a gusting crosswind without tangling
> with the runway lighting system.
George brings up something I had forgotten about.
There is one model of the Maule that is particularly "aileron
challenged". You quickly run out of roll authority in a cross wind due
to the relatively small ailerons, necessitating an increase in airspeed
to regain the necessary stability.
The other thing I have noticed in this thread is the differences of
opinion held by pilots of conventional gear and tricycle gear aircraft.
Depending on the type of aircraft you are used to flying, your opinion
on technique is shaped by necessity.
Newps
not, you are making the wing bigger.
Peter Duniho
news:3ED516DF...@nowhere.com...
> > I don't know. Most GA aircraft have flaps that will increase drag only
> > beyond 20 degress, not lift.
>
> not, you are making the wing bigger.
He didn't say it wouldn't. He just said that past 20 degrees, there's "no"
increase in lift (there's actually a tiny increase, but most of the change
is drag past that point).
Pete
Koopas Ly
I don't understand here. You say that you want all the drag once on
the ground. Then, why do you quickly retract flaps after touching
down when executing a short-field landing? By retracting flaps, you
dump lift and put the weight of the airplane on the main wheels, a
desirable condition for braking.
Alex
Thomas Borchert <borcher...@hotmail.com> wrote in message news:<VA.00005ed...@hotmail.com>...
Koopas Ly
Please see my comments below. I kindly ask that you reply below my
questions. Thanks.
rdu...@compuserve.com (Rick Durden) wrote in message news:<d9fecbe.03052...@posting.google.com>...
> Alex,
>
> Yes, the gust factor is the amount of the max gust reported above the
> steady state wind. You add NO speed for a steady state wind...there
> is no reason to do so. Published approach speed is already 1.3 times
> stall speed and provides plenty of control authority and the
> ability to flare power off...adding speed only means float, which
> causes directional control problems or landing on the nose gear, which
> can be very ugly. Add one half of gust factor.
Ok, I had mistakenly understood that you'd add half of the gust speed.
Not half of the gust reported ABOVE the steady state wind speed.
>
> When a gust ends the effect on the airplane is to lose airspeed by the
> amount of the gust. Because we fly little airplanes that accelerate
> relatively well in such circumstances, even with full flaps,
> particularly because simply adding a little power puts airflow from
> the prop over the wings, the airspeed loss is no big deal. Adding
> extra speed is much more of a problem.
I am not understanding what you're trying to convey. Could you
restate?
>
> No, you don't want just lift flaps.
I never talked about lifting flaps. I just mentioned using 20 degrees
of flaps versus full flaps since:
1. stall speed is about the same for 20-deg. and full flaps - thus
20-deg. of flaps allows for the about the same *reduced* approach
speed.
2. much less drag at 20-deg. flaps. Less power required.
> You need the drag to help you
> decelerate and to stop the airplane from floating.
I think I can see where you're going with this. You're implying that
there's not much difference in lift between partial flaps (20 deg.)
and full flaps but that there's much more drag at full flaps, which
should help you in dumping airspeed once you flare?
> Floating when you
> flare is what starts the whole process of loss of control. You've
> been keeping the airplane straight on the approach, so flare and plant
> it before you lose control. That means max drag in the flare. By
> closing the throttle you get the drag from the prop. With flaps, that
> means you don't float if you are on speed.
See my previous comment.
> On touchdown you crank in
> all the rest of the aileron deflection to take advantage of adverse
> aileron yaw to assist with directional control and keep the weight on
> the upwind tire
I don't know how much adverse yaw you'd have to help out with
directional control. Wouldn't full rudder downwind help more
effectively?
> and you use to flaps to help declerate as fast
> as possible to a speed where you have rolling control. Deceleration
> in the first third of the landing roll is mainly aerodynamic as the
> tires aren't really gripping yet (there is experimental data on that
> from hydroplaning studies). Then, get the flaps up to dump the lift
> and get the weight on the wheels for rolling and braking control.
With short-field landings, I am taught to retract flaps as soon as the
mains touch to dump lift and get the weight on wheels, and step on the
brakes. So to sum up, you're advising to leave full flaps extended
until the mains touchdown for max drag and deceleration. Then,
following the mains touching down, to retract the flaps to dump lift
and braking effectiveness. Is that what you're preaching?
So why isn't everyone using full flaps when landing? Could you
reiterate the advantages (if any) to using 1/ partial flaps and/or
2/ a higher approach speed?
Thanks.
Alex
Rick Durden
> Please see my comments below. I kindly ask that you reply below my
> questions. Thanks.
I'll give it a shot <g>
>
>
> > Yes, the gust factor is the amount of the max gust reported above the
> > steady state wind. You add NO speed for a steady state wind...there
> > is no reason to do so. Published approach speed is already 1.3 times
> > stall speed and provides plenty of control authority and the
> > ability to flare power off...adding speed only means float, which
> > causes directional control problems or landing on the nose gear, which
> > can be very ugly. Add one half of gust factor.
>
> Ok, I had mistakenly understood that you'd add half of the gust speed.
> Not half of the gust reported ABOVE the steady state wind speed.
>
>
> >
> > When a gust ends the effect on the airplane is to lose airspeed by the
> > amount of the gust. Because we fly little airplanes that accelerate
> > relatively well in such circumstances, even with full flaps,
> > particularly because simply adding a little power puts airflow from
> > the prop over the wings, the airspeed loss is no big deal. Adding
> > extra speed is much more of a problem.
>
>
> I am not understanding what you're trying to convey. Could you
> restate?
When the aircraft is moving through an airmass moving at a steady
speed, the aircraft will hold a constant airspeed for a given pitch
attitude and power setting. A gust coming from the front of the
airplane (as is the case most of the time on landing) will increase
the airspeed of the airplane temporarily by the magnitude of the
gust. However, the airplane is slightly resistent to acceleration, so
the increase is some number less than the gust and the airplane will
pitch up to seek to return to its trim speed. When the gust
ends, the airspeed increase will go away as the airplane is again
flying in the steady state airmass and the airplane will begin to
pitch down as it is not so far away from its trim speed as it was. A
gust from astern has the opposite effect. Because little airplanes
handles gusts and wind shear much better than jets, it's not
necessary to add much speed for gusts. If there as a gust from
astern or shear that causes a reduction of airspeed just adding power
fixes most of the problem because the propwash over the wing reduces
the stall speed at the same time the airplane is accelerating, two
positives. Using full flaps also makes the airplane more resistent
to gust because it is more resistent to acceleration and thus the
airspeed fluctuations in gusts are smaller.
>
>
> >
> > No, you don't want just lift flaps.
>
> I never talked about lifting flaps. I just mentioned using 20 degrees
> of flaps versus full flaps since:
Yes, you did talk about lift flaps. 20 degrees of flap in a 172 is
lift flap, as to that point they are primarily reducing stall speed
rather than increasing drag.
>
> 1. stall speed is about the same for 20-deg. and full flaps - thus
> 20-deg. of flaps allows for the about the same *reduced* approach
> speed.
>
> 2. much less drag at 20-deg. flaps. Less power required.
Why should power be required on an approach, with or without flaps?
If you are using lots of power you are probably approaching too
flat. Okay, few people use power off approaches, but approaching
with partial flap because less power is required is not a compelling
reason.
>
>
> > You need the drag to help you
> > decelerate and to stop the airplane from floating.
>
> I think I can see where you're going with this. You're implying that
> there's not much difference in lift between partial flaps (20 deg.)
> and full flaps but that there's much more drag at full flaps, which
> should help you in dumping airspeed once you flare?
Precisely.
>
>
> > Floating when you
> > flare is what starts the whole process of loss of control. You've
> > been keeping the airplane straight on the approach, so flare and plant
> > it before you lose control. That means max drag in the flare. By
> > closing the throttle you get the drag from the prop. With flaps, that
> > means you don't float if you are on speed.
>
> See my previous comment.
>
>
> > On touchdown you crank in
> > all the rest of the aileron deflection to take advantage of adverse
> > aileron yaw to assist with directional control and keep the weight on
> > the upwind tire
>
> I don't know how much adverse yaw you'd have to help out with
> directional control. Wouldn't full rudder downwind help more
> effectively?
Yes, you are using rudder, however, in crosswind you should touch
down on the upwind wheel and keep there airplane on that wheel as you
progressively increase aileron deflection to full travel, to stop
the airplane from sliding sideways. Particularly at higher angles of
attack, such as at touchdown, the adverse aileron yaw is hugely
beneficial for directional control. Next time you taxi a tailwheel
airplane on a calm day or into the wind, try steering on the ground
by applying opposite aileron to the direction you desire to turn...it
results in a gentle turn.
>
>
> > and you use to flaps to help declerate as fast
> > as possible to a speed where you have rolling control. Deceleration
> > in the first third of the landing roll is mainly aerodynamic as the
> > tires aren't really gripping yet (there is experimental data on that
> > from hydroplaning studies). Then, get the flaps up to dump the lift
> > and get the weight on the wheels for rolling and braking control.
>
>
> With short-field landings, I am taught to retract flaps as soon as the
> mains touch to dump lift and get the weight on wheels, and step on the
> brakes. So to sum up, you're advising to leave full flaps extended
> until the mains touchdown for max drag and deceleration. Then,
> following the mains touching down, to retract the flaps to dump lift
> and braking effectiveness. Is that what you're preaching?
In essence, yes. The drag from the flaps is more effective than
braking the wheels during about the first third of the rollout, so
you don't have to snatch the flaps up immediately in a short field
landing. On a gusty day or in a crosswind it helps to retract the
flaps early to get more weight on the wheels.
>
>
> So why isn't everyone using full flaps when landing? Could you
> reiterate the advantages (if any) to using 1/ partial flaps and/or
> 2/ a higher approach speed?
Because most people fly on nice days when control is not an issue and
it "feels" much better to fly final fast, with partial flaps and the
pitch change in the flare is less...plus it takes a little more skill
to land with full flaps. We've gotten lazy with tricycle gear
airplanes and feel as if the landing is over when the wheels touch,
so pilots concentrate on the approach and touchdown rather than the
rollout, which is where they get bit when its gusty or when the
crosswind is blowing.
It's in more detail in the reference I gave you.
All the best,
Rick
>
>
> >
> > For a longer discussion of this subject, go to
> > www.avweb.com/news/columns/182656-1.html
> >
> >
> >
karl gruber
*****The accident data is pretty clear, the slower you touch down, the less
the chance of an accident in a
I just went over the first few hundred of "loss of directional control on
landing" accidents on the NTSB site. Not one accident listed too high a
speed or not enough flaps.
******I understand what you are saying, however, you still need to touch
down as slowly as possible to take advantage of the lateral holding ability
of the tires ******
If you want the tires to grip you will want less flaps, not more. In fact NO
FLAPS provides the best grip.
******If pilots would simply fly at the published approach speeds, plus half
the gust factor, use all the flaps available and crank in full aileron
deflection on touchdown, we'd all be paying less for insurance.******
I don't think so. Flaps provide more sail area. If there is just a small
deviation in directional control the crosswind will use the full flaps as a
sail and push the airplane into a ground loop.
******Then, get the flaps up to dump the lift and get the weight on the
wheels for rolling and braking control.*****
There is no such thing as "dumping flaps on most Cessnas, since they have
monotonously slow electric flaps. It is better to just land with NO FLAPS in
a strong crosswind. Then there is no additional sail area to push you
sideways and you have immediate weight on the wheels for braking.
******Using full flaps also makes the airplane more resistant to gust
because it is more resistant to acceleration*****
Just the opposite. Full flaps make the airplane MORE susceptible to gusts
and make the airplane MORE susceptible to acceleration, just by the fact
that there is more lift.
In my experience flying Skywagons for many decades, the best crossing
landing is with no flaps, three point, speed as necessary. I've tried ALL
the other "missionary" techniques, and even was a proponent of wheel
landings for a time, but not now. I want the tail on the ground for
directional control, the mains on the ground firmly for braking.
Best,
Karl
curator, N185KG
Big John
Your right. However there are two sides of this argument and they will
never agree. Reason I haven't put my comments in thread.
Been there, done that like you say for years and thousands of hours.
Big John
Point of the sword
Roger Halstead
wrote:
>Thomas,
>
>I don't understand here. You say that you want all the drag once on
>the ground. Then, why do you quickly retract flaps after touching
>down when executing a short-field landing? By retracting flaps, you
>dump lift and put the weight of the airplane on the main wheels, a
>desirable condition for braking.
First, I am not advocating any one try things the way I do them
without having an instructor who is familiar with the technique show
them how. Like anything different than what you have been
doing..."Get and Instructor".
I don't retract flaps once on the ground.
It depends on what you are flying and the techniques being used.
Getting rid of the flaps works great in the old Cherokees with the
Johnson Bar flaps where you can get rid of the extra lift almost
instantaneously.
In something like a Bonanza, or even 172s with electric flaps, I've
found I'm usually slowed to the point where the removing the flaps is
not an issue by the time they have retracted. IE They don't retract
fast enough to do any good in shortening the landing by much. That and
both the 152 and 172 have such light wing loading they tend to float
even when just a few mph faster than book figures.
Instead, I use aerodynamic breaking. As soon as the mains are down, I
let the nose gear down and get on the he breaks. As soon as I can feel
the breaking working I bring the yoke back. That *should* put
pressure down on the mains to even add to the effectiveness of
breaking and it adds a lot of drag early on in the roll out where it
is the most effective.
If you fly Cherokees and Bonanzas along with 152s and 172s you will
find there is not much too the myth that low wings are more prone to
float...Neglecting Moonies. The heavier wing loading more than makes
up for being closer to the runway in most cases.
Book figures for the Bo (F-33 and Deb) show landing distances shorter
than some 172s. I can normally beat the book figures when using a
*steep* descent and the aerodynamic breaking.
I had a chance to do some comparisons today.
It was Bi-ennual time and John and I decided to really do a workout.
My last landing was a *no flap* landing with a 15 knot, 90 degree
cross wind from the right. It went just fine, but was far, far, more
work, for a lot longer than the same landing using those great big
flaps at 40 degrees. Not only was it windy (I had the ailerons
against the stops shortly after the nose gear touched down), but there
were lots of thermals and the ASI was varying as much as 20 MPH on
final. (boy, but that makes for good leg muscles). The steeper
final, slower (with power) and full flaps made for much shorter and
more secure landings.
Admittedly there are probably not many who land with 15 knot, 90
degree cross winds on a regular basis.
BTW, we had a crash at the airport yesterday.
The reason....It was windy, the pilot was not competent for the
conditions, and he was carrying too much speed. He forced it on,
creating a "Porpoise", which made (you guessed it) three times. The
third time it hit (according to witnesses) at roughly a 30 degree nose
down angle which broke the nose gear attach points, bent the fire wall
and belly..Prop and engine .and numerous other parts. No injuries,
but one of, it not the nicest 172 on the field is probably totaled.
Roger Halstead (K8RI EN73 & ARRL Life Member)
www.rogerhalstead.com
N833R World's oldest Debonair? (S# CD-2)
That 3000# airplane is just a lot easier to land with full flaps and
about 20 MPH slower with a 90 degree cross wind.
Roger Halstead
<skywagon1...@msn.com> wrote:
>Rick Durden:
>*****The accident data is pretty clear, the slower you touch down, the less
>the chance of an accident in a
>crosswind.*****
>
>I just went over the first few hundred of "loss of directional control on
>landing" accidents on the NTSB site. Not one accident listed too high a
>speed or not enough flaps.
How many did you see with the word "Porpoise" in them?
Some one mentioned it earlier...We need to discern at the start
whether we are talking nose draggers, or tail draggers. They fly the
same, their take offs are similar, but their landings are a world
apart.
I think too, it is time to impress on students that there are great
differences in airplanes and they should not expect all airplanes to
fly like, or behave like the trainers. Some are downright ill
tempered and will suffer no laps of judgement from their pilots.
"In general" older aircraft designs and faster aircraft designs are
less forgiving.
>
>******I understand what you are saying, however, you still need to touch
>down as slowly as possible to take advantage of the lateral holding ability
>of the tires ******
>
>If you want the tires to grip you will want less flaps, not more. In fact NO
>FLAPS provides the best grip.
>
Not when you are going faster. Faster adds lift.
Say with flaps you touch down at 40 MPH and could touch down at the
same speed with out flaps. Then I'd agree. Unfortunately without flaps
you probably touch down at 50 MPH, or faster with no more weight on
the mains that at 40 with flaps.
We did a bit of experimenting today (in a nose dragger) and even with
strong cross winds the landings were more secure using full flaps and
slower speeds.
>******If pilots would simply fly at the published approach speeds, plus half
>the gust factor, use all the flaps available and crank in full aileron
>deflection on touchdown, we'd all be paying less for insurance.******
>
>I don't think so. Flaps provide more sail area. If there is just a small
I do. The FAA has been harping on this (in the wings program) for
some time and even sent out a circular some time ago about flying
published speeds instead of adding a bit extra. They were basically
saying "speed kills" and it was a big enough problem to cause them to
send out that circular.
You should have heard the grousing when the AirSafety Foundation told
us (a group of 60 Bo pilots) that we would be flying book figures. Bo
pilots are notorious for adding a "little extra". Actually it is
usually more than a little extra.
For example on mine, power out landings take a 90 MPH final while the
power on final is substantially slower. With only a couple of
exceptions they were flying final at 90 "plus a little extra" for
comfort. There were only two of us who were taught and used book
speeds. None of them knew that the Bo makes a very good short field
aircraft. (Ignoring the small nose gear and low wing in brush)
>deviation in directional control the crosswind will use the full flaps as a
>sail and push the airplane into a ground loop.
Not in a tricycle gear. Again, we found the landings using 40 degree
flaps today to be much more secure (solid if you will)
>
>******Then, get the flaps up to dump the lift and get the weight on the
>wheels for rolling and braking control.*****
>
>There is no such thing as "dumping flaps on most Cessnas, since they have
>monotonously slow electric flaps. It is better to just land with NO FLAPS in
>a strong crosswind. Then there is no additional sail area to push you
>sideways and you have immediate weight on the wheels for braking.
True about the slow flaps...
But... Again, I disagree, but it depends on the pilots familiarity
with flying in strong winds. The flaps do not appear to work like a
sail and landing faster with no flaps reduces the load on the gear. It
does not increase it. IF OTOH you are at the full flap speed and
remove the flaps the load on the gear does increase. Unfortunately
with electric flaps they do not come out very fast.
>
>******Using full flaps also makes the airplane more resistant to gust
>because it is more resistant to acceleration*****
>
>Just the opposite. Full flaps make the airplane MORE susceptible to gusts
>and make the airplane MORE susceptible to acceleration, just by the fact
>that there is more lift.
It probably depends to some extent on the airplane, but full flaps "to
me" reduce the time you are affected by the gusts. Particularly cross
wind gusts. Remember that full flaps add far more drag than lift
and they slow the plane much more quickly.
Again, I had a lot of experience (with an instructor) with that very
subject today.
>
>
>In my experience flying Skywagons for many decades, the best crossing
>landing is with no flaps, three point, speed as necessary. I've tried ALL
>the other "missionary" techniques, and even was a proponent of wheel
>landings for a time, but not now. I want the tail on the ground for
>directional control, the mains on the ground firmly for braking.
Which says you are flying an airplane that is quite different than
what *most* of the students here are flying. OTOH the Deb is not
exactly typical either.
In today's environment, for all practical purposes, the trainer is a
nose dragger and not a tail dragger. That may not be best, but it is
what we have. Unfortunately the nose dragger does leave out the
necessity of learning some very good skills.
Roger Halstead (K8RI EN73 & ARRL Life Member)
www.rogerhalstead.com
N833R World's oldest Debonair? (S# CD-2)
>
>Best,
>Karl
>curator, N185KG
>
>
>
>
john smith
> whether we are talking nose draggers, or tail draggers. They fly the
> same, their take offs are similar, but their landings are a world
> apart.
> I think too, it is time to impress on students that there are great
> differences in airplanes and they should not expect all airplanes to
> fly like, or behave like the trainers. Some are downright ill
> tempered and will suffer no laps of judgement from their pilots.
The physics are different between conventional (tail dragger) and
tricycle gear airplanes. The wing (angle of incidence) on a tail dragger
will fly with the stick neutral once it reaches minimum speed (three
point takeoffs and landings). A comparable tricycle gear airplane
requires an elevator down force to rotate the wing to the minimum angle
of incidence for flight, pressing all the weight on the mains. (Some
tail dragger pilots will push the stick forward to lift the tail at low
speed, placing all the weight on the mains, neutralize the stick, then
pull back to takeoff, the same as a tricycle gear airplane.)
Since the tail dragger naturally sits with its wing ready to fly, it is
more susceptible to the actions of the wind. How often do you see a
tricycle gear airplane pilot taxiing with the ailerons in the proper
position for the wind?
In "THE COMPLETE TAIL DRAGGER PILOT" (Harvey Plourde), he explains how
the selection of flaps depends upon the size of the flaps on a
particular aircraft. He compares the use of flaps on a Cessna 140 to
that of a Cessna 180. He recommends "10 degrees or one notch unless the
POH or experience in the airplane dictate otherwise."
He also discusses the "crab" versus the "slip" approach, pointing out
that tricycle gear airplanes are more forgiving of side loads than
conventional gear airplanes. He also points out that the Ercoupe is an
example of an airplane that must be landed in a crab due to the lack of
separate rudder input.
Of 27 pages devoted to the chapter on crosswind operations, 9 discuss
takeoff, the remaining 18 discuss landing.
Rick Durden
Good to hear from you.
"karl gruber" <skywagon1...@msn.com> wrote in message news:<bb5c6o$615p2$1...@ID-161519.news.dfncis.de>...
> Rick Durden:
> *****The accident data is pretty clear, the slower you touch down, the less
> the chance of an accident in a
> crosswind.*****
>
> I just went over the first few hundred of "loss of directional control on
> landing" accidents on the NTSB site. Not one accident listed too high a
> speed or not enough flaps.
Actually, you didn't. You read the summaries. The factual reports
are not on the website. You have to get the factual report that has
flap deflection shown as well as a more thorough narrative.
>
> ******I understand what you are saying, however, you still need to touch
> down as slowly as possible to take advantage of the lateral holding ability
> of the tires ******
>
> If you want the tires to grip you will want less flaps, not more. In fact NO
> FLAPS provides the best grip.
That's correct, tires get the best grip rolling slowly with flaps up,
which is why you touch down with full flaps, as slowly as possible,
use the flaps to assist deceleration initially while aerodynamic
control is still effective and the flaps provide braking, then retract
them, something especially effective in your 185 because the flaps
move fast.
>
> ******If pilots would simply fly at the published approach speeds, plus half
> the gust factor, use all the flaps available and crank in full aileron
> deflection on touchdown, we'd all be paying less for insurance.******
>
> I don't think so. Flaps provide more sail area. If there is just a small
> deviation in directional control the crosswind will use the full flaps as a
> sail and push the airplane into a ground loop.
Actually, that's not true and I'd be interested in seeing data to
support your position. Groudloops are less frequent in airplanes
that have flaps and in circumstances where they are used. Flaps do
not provide the side load required for ground loops, they load
directly aft.
>
> ******Then, get the flaps up to dump the lift and get the weight on the
> wheels for rolling and braking control.*****
>
> There is no such thing as "dumping flaps on most Cessnas, since they have
> monotonously slow electric flaps. It is better to just land with NO FLAPS in
> a strong crosswind. Then there is no additional sail area to push you
> sideways and you have immediate weight on the wheels for braking.
Flaps do not push one sideways, they are not sails, they load aft.
Also, fly one of the new Cessnas. They have very fast flaps. I was
surprised the first time I experienced it. However, even slow acting
flaps put load on the wheels fast. The simple act of starting the
flaps up, even if they move slowly, begins to dump lift as every pilot
has experienced on a go around when flaps up is selected and the
airplane sinks alarmingly.
>
> ******Using full flaps also makes the airplane more resistant to gust
> because it is more resistant to acceleration*****
>
> Just the opposite. Full flaps make the airplane MORE susceptible to gusts
> and make the airplane MORE susceptible to acceleration, just by the fact
> that there is more lift.
The lift is constant once the flaps are established. A gust acting on
an airplane with full flaps will cause less acceleration and less
deflection of the aircraft because drag of the flaps prevent it from
accelerating as fast as an airplane with less drag.
>
>
> In my experience flying Skywagons for many decades, the best crossing
> landing is with no flaps, three point, speed as necessary. I've tried ALL
> the other "missionary" techniques, and even was a proponent of wheel
> landings for a time, but not now. I want the tail on the ground for
> directional control, the mains on the ground firmly for braking.
I won't argue three-point versus wheel because it is very much
airplane and pilot dependent. I won't three-point a Swift but I
usually do so in a 185. Also, for a pilot who knows his airplane
and flies it well, the cross wind technique that works for him or
her is the best. However, for pilots as a group in little airplanes,
they are less likely to wreck the airplane on landing if they use
more flaps, not less, because they are less likely to lose control
during the deceleration phase.
All the best,
Rick
>
> Best,
> Karl
> curator, N185KG
Cub Driver
> (Some
>tail dragger pilots will push the stick forward to lift the tail at low
>speed, placing all the weight on the mains, neutralize the stick, then
>pull back to takeoff, the same as a tricycle gear airplane.)
I was amazed the difference between a Cub and a Husky, The latter will
just fly off the ground with the stick neutral the whole time. If you
try that in a Cub you will beat the poor wheels to death; you really
need forward stick for a hundred feet to keep the wheels on the
ground, then relax and it flies off. I don't seem to find it necessary
to use back stick in either plane.
all the best -- Dan Ford (email: web AT danford.net)
see the Warbird's Forum at http://www.danford.net/index.htm
Vietnam | Flying Tigers | Pacific War | Brewster Buffalo | Piper Cub
Cub Driver
>I don't retract flaps once on the ground.
I had one instructor order me not to touch the flap bar (Super Cub)
till the plane stopped. Another insisted that I clean them up
immediately, this for a bush-flying course in the Husky.
karl gruber
Here's a question for you. When you are sailing your Super Cub floatplane
and you put down the flaps, does your waterspeed increase?
To be continued!
Karl
Rick Durden
Here's a question for you. When you are sailing your Super Cub
floatplane
> and you put down the flaps, does your waterspeed increase?
Indeed it does, straight aft, no side load is generated. There is no
turning tendency. In order to generate a turn, there must be aileron
or rudder input.
>
> To be continued!
Absolutely!
All the best,
Rick
karl gruber
turning tendency.********
Oh! But there is in a crosswind.
Landing in a crosswind:
The flap on the upwind side has direct access to the crosswind and is ready
to provide a strong turning moment.
The flap on the downwind side has the fuselage in the way of the crosswind
and will not have enough moment to counteract the upwind flap.
Get sideways at all and the xwind force on the upwind flap will generate a
turning moment aft of the CG and you WILL turn into the wind faster than
without flaps.
Demonstrated very easily in your floatplane with a stopwatch.
Best,
Karl
Curator, N185KG
David Megginson
> Why should power be required on an approach, with or without flaps?
> If you are using lots of power you are probably approaching too
> flat. Okay, few people use power off approaches, but approaching
> with partial flap because less power is required is not a compelling
> reason.
A while ago, I ran some calculations, and I think I figured out that
about 1500 rpm was a neutral approach setting for a C-172 or PA-28 at
70 kt -- no thrust, no drag (as if you could just fold back the
propeller blades and glide in). Does that sound about right?
All the best,
David
--
David Megginson, da...@megginson.com, http://www.megginson.com/
EDR
> about 1500 rpm was a neutral approach setting for a C-172 or PA-28 at
> 70 kt -- no thrust, no drag (as if you could just fold back the
> propeller blades and glide in). Does that sound about right?
Minimum speed will be with full elevator up trim.
John
wrote:
> rdu...@compuserve.com (Rick Durden) writes:
>
> > Why should power be required on an approach, with or without flaps?
> > If you are using lots of power you are probably approaching too
> > flat. Okay, few people use power off approaches, but approaching
> > with partial flap because less power is required is not a compelling
> > reason.
>
> A while ago, I ran some calculations, and I think I figured out that
> about 1500 rpm was a neutral approach setting for a C-172 or PA-28 at
> 70 kt -- no thrust, no drag (as if you could just fold back the
> propeller blades and glide in). Does that sound about right?
>
I think 1550 sounds a bit high for a 172, at least. My "gut" says that it
would be more like 900-1200 rpm (closed throttle being ~ 700-750).
>
> All the best,
>
>
> David
David Megginson
> > A while ago, I ran some calculations, and I think I figured out that
> > about 1500 rpm was a neutral approach setting for a C-172 or PA-28 at
> > 70 kt -- no thrust, no drag (as if you could just fold back the
> > propeller blades and glide in). Does that sound about right?
> >
> I think 1550 sounds a bit high for a 172, at least. My "gut" says that it
> would be more like 900-1200 rpm (closed throttle being ~ 700-750).
I checked my math, and it's closer to 1400 rpm than 1500 rpm. Here
are my calculations, so that others can correct any mistakes.
70 kcas is 7088 fpm. My Warrior's 60-inch fixed-pitch propeller
advances through the air 5 feet for every revolution. That means that
at 70 kcas, the propeller would produce no thrust or drag at 7088/5 =
1417 rpm. Any faster, and the propeller is producing thrust; any
slower, and it's windmilling and producing drag.
For 60 kcas (6076 fpm), the neutral speed would be 1215 rpm; for 80
kcas (8102 fpm), the neutral speed would be 1620 rpm. If I understand
this information correctly, once you slow the rpm past those speeds,
you're effectively using the prop/engine as an airbrake.
And finally, a pedantic note. 70 kias in my Warrior is actually 73
kcas (7393 fpm) with no flaps, so the neutral speed is 1478 rpm. My
full-flap approach speed is 63 kias, which is actually 65 kcas (6583
fpm), so the neutral speed for full-flap short final at 63 kias is
1316 rpm, much closer to John's gut feeling.
Rick Durden
It sounds very close.
All the best,
Rick
David Megginson <da...@megginson.com> wrote in message news:<87y90ok...@megginson.com>...
Mark Kolber
<da...@megginson.com> wrote:
>> I think 1550 sounds a bit high for a 172, at least. My "gut" says that it
>> would be more like 900-1200 rpm (closed throttle being ~ 700-750).
>
>I checked my math, and it's closer to 1400 rpm than 1500 rpm. Here
>are my calculations, so that others can correct any mistakes.
And, of course since the actual glide path is based on ground speed
not airspeed, your best calculation within 50 rpm is only an estimate
anyway.
Unless, of course you're planning to recalculate for the wind
conditions. Should be interesting in gusty conditions.
Mark Kolber
APA/Denver, Colorado
www.midlifeflight.com
======================
email? Remove ".no.spam"
David Megginson
> >I checked my math, and it's closer to 1400 rpm than 1500 rpm. Here
> >are my calculations, so that others can correct any mistakes.
>
> And, of course since the actual glide path is based on ground speed
> not airspeed, your best calculation within 50 rpm is only an estimate
> anyway.
>
> Unless, of course you're planning to recalculate for the wind
> conditions. Should be interesting in gusty conditions.
I think I'm missing something here, or else two subthreads have
crossed lines -- whether any particular fixed-pitch propeller is
windmilling or not will depend only on RPM and calibrated airspeed,
not groundspeed or glidepath, as far as I understand.
EDR
> crossed lines -- whether any particular fixed-pitch propeller is
> windmilling or not will depend only on RPM and calibrated airspeed,
> not groundspeed or glidepath, as far as I understand.
This discussion is about power on, zero thrust RPM.
You will notice that the discussion of engine RPM in a power off glide
has not been raised.
What glide speed must be attained to generate the discussed zero thrust
1550 RPM in a power off condition?
David Megginson
> What glide speed must be attained to generate the discussed zero thrust
> 1550 RPM in a power off condition?
You're always going to end up windmilling (i.e. slower than
zero-thrust speed), because the engine is not producing any power.
ske...@no-fixed-abode.com
wrote:
> "John" <step...@no-fixed-abode.com> writes:
>
> > > A while ago, I ran some calculations, and I think I figured out that
> > > about 1500 rpm was a neutral approach setting for a C-172 or PA-28 at
> > > 70 kt -- no thrust, no drag (as if you could just fold back the
> > > propeller blades and glide in). Does that sound about right?
> > >
> > I think 1550 sounds a bit high for a 172, at least. My "gut" says that it
> > would be more like 900-1200 rpm (closed throttle being ~ 700-750).
>
> I checked my math, and it's closer to 1400 rpm than 1500 rpm. Here
> are my calculations, so that others can correct any mistakes.
>
> 70 kcas is 7088 fpm. My Warrior's 60-inch fixed-pitch propeller
> advances through the air 5 feet for every revolution. That means that
> at 70 kcas, the propeller would produce no thrust or drag at 7088/5 =
> 1417 rpm. Any faster, and the propeller is producing thrust; any
> slower, and it's windmilling and producing drag.
Hey -- are you trying to tell us that 60-inch refers to pitch, not diameter?
An aircraft propeller is not like a boat propellor, with a defined pitch.
It is an aerofoil, and moves the plane forward through lift, not by
"screwing" its way through an uncompressible medium (like water).
I think your calculation is unrelated to what is really happening.
Roy Smith
> An aircraft propeller is not like a boat propellor, with a defined pitch.
> It is an aerofoil, and moves the plane forward through lift, not by
> "screwing" its way through an uncompressible medium (like water).
Aircraft and boat props are much more alike than you seem to think.
They both generate lift by creating high and low pressure areas on their
faces. Obviously there are differences due the the different densities
of the fluids they operate in, but the basic principles are the same.
David Megginson
> Hey -- are you trying to tell us that 60-inch refers to pitch, not
> diameter? An aircraft propeller is not like a boat propellor, with
> a defined pitch. It is an aerofoil, and moves the plane forward
> through lift, not by "screwing" its way through an uncompressible
> medium (like water).
The propeller on my Warrior II is 60-inch pitch and 74-inch diameter.
The full designation is Sensenich 74DM6-0-60.
David Megginson
Here's what I understand so far: there is a forward velocity for any
given fixed-pitch propeller at any given RPM that will cause the
blades to produce neither positive nor negative lift. That's what I
understand the meaning of 60-inch pitch to be -- if the propeller
moves forward through the air 60 inches for each rotation, the blades
will not produce any lift at all (i.e. no thrust or drag, when we
rotate the reference to the aircraft axes).
Joseph D. Farrell
lat week I was ending an instrument lesson and the ASOS was reporting
310-10G14 as I was setting up to land on 27.
Muy downwind was not as fast as it usually was, and then my base
seemed to take a long time.
When I turned final I was in a 80-90 degree X wind - the wind had
shifted on a dime. I'd say the avg Xwind was 13-14kts. No big deal
but there was a stupid helicopter at the departure end of 27 doing
whatever they do and generally being in the way for fixed wing ac.
Changing runways would have been awkward, other planes were in and
approaching the pattern for 27, and the go around at that point would
have lost touch with the chopper who was NOT doing normal things and a
poor job of announcing them.
I mentioned the dilemma to my instructor [all on final - which oh
primary students gives you a lot more time to look around and discuss
such things when you have a couple hundred hours] and he concured with
continuing hte approach.
So = in a Cherokee 180 I had almost full rudder in a slip into the
wind [almost full, remembering a Cherokee has a 17kt Xwind component
demonstrated] - full flaps and about 1700 or 1800 rpm down the shoot
at 80mph on short final decaying to 75 over the fence and then into
rotation speeds at touchdown. Got the stall warning about hairswdith
off the ground and on we went, low wing first, pivot it straight and
power off and we are down - more or less on the centerline.
I simply flew the airplane onto to the ground at ever-decreasing
speeds in a slip, pulling a little throttle out the whole way to slow
down. The wind shift is what was surprising.
If you are a student pilot - as you fly regularly you WILL develop
this skill. And it is fun when you do! It becomes as routine as
breathing - even if you are task saturated now just getting it on the
runway.
Personally, I trim the airplane for 85mph [mph in a -180] which is
best rate of climb speed since all an approach is truly is an approach
to a go-around. EVERYTHING I do in my landing routine is designed to
make the airplane climb at Vy. Then I have to hold the nose down on
final and as the throttle comes out to land you can feel the stick
forces translate to a nose down to keep the airspeed at 85 - so that a
flare requires you actively pull the nose up since the airplane is
trimmed for 85 and you are going 70 or so in the flare.
Wanna do a short field approach? Trim it for 75mph. Trim is your
friend, learn how to use it and know where your airplane's trim
positions are - they'll save your butt one day.
Have fun - Joe Farrell
N8846J
John Roncallo
"Joseph D. Farrell" <joefa...@direcway.com> wrote in message
news:12emdvcghv5e5titv...@4ax.com...
> strong winds require a different touch . . .
>
> lat week I was ending an instrument lesson and the ASOS was reporting
> 310-10G14 as I was setting up to land on 27.
>
> Muy downwind was not as fast as it usually was, and then my base
> seemed to take a long time.
>
> When I turned final I was in a 80-90 degree X wind - the wind had
> shifted on a dime. I'd say the avg Xwind was 13-14kts. No big deal
> but there was a stupid helicopter at the departure end of 27 doing
> whatever they do and generally being in the way for fixed wing ac.
The helicopter is not stupid. They are most probably practicing what
helicopters can and should do. Probably practicing something like extracting
a fixed wing pilot from an airplane that crashed in the mountains with power
lines all over the place. Communication is a big help here. If you were
unsure of what the helo was doing you could just ask. "Helicopter at end of
rwy 27, Cherokee is final for 27 what are your intensions". You might be
supprised to get a reply like: "helicopter going to flat pitch on north
taxiway". I realize this little bit of communication is difficult especially
with students that have there hand full in windy conditions but once you get
used to it it becomes as automatic as breathing.
I have found it unfortunate that primary fixed wing aircraft training does
not go into enough detail in ground school of helicopter and IFR operations.
And I'm sure there are some out there that feel I should include ballons,
gliders, airships, ultralights. I remember the first time a helicopter
announced to me he was departing from the taxi way; I thought he had a lot
of nerve. The truth is the ability for the helicopter to do this makes the
traffic congestion a lot easier to deal with when high and low speed
aircraft share the same pattern. At uncontrolled airports fixed wings
typically make left traffic and helicopters make right traffic usually at a
lower altitude. If a helicopter find itself in conflict on final with a
fixed wing it can always shift to the grass or taxiway and finish the
landing (neat huh). Good communication is in order here. At the same time
helicopter pilots should always keep in mind the path a fixed wing may
execute on a go-around. Typically ending up nose to nose with a down wing
helicopter again good comunication helps alot. Always look for helicopters
high in the sky the standard approach angle for a helicopter is 15° compared
to a 3° for fixed wings. If you here the word autorotation its more like
45°.
The same communication goes for IFR pilots talking to VFR pilots. Switching
over to CTAF and anouncing you are 1700' inbound on the NDB 36 approach at
STARK means as much to all the people who can hear you, and might give a
S@#&!, as if you said you were on the moon. Now saying your 1700' 5 miles
south of MMK on the NDB 36 gives both VFR and IFR pilots some usable
information.
> Changing runways would have been awkward, other planes were in and
> approaching the pattern for 27, and the go around at that point would
> have lost touch with the chopper who was NOT doing normal things and a
> poor job of announcing them.
How do you know they were NOT normal things. Flying is not normal to most
people.
If he or she announced something like "Helicopter Air taxi Rwy 27" would
you have known what it meant? Would it have meant the runway was clear?
Granted he or she should have anounced it regaurdless!
> I mentioned the dilemma to my instructor [all on final - which oh
> primary students gives you a lot more time to look around and discuss
> such things when you have a couple hundred hours] and he concured with
> continuing hte approach.
>
> So = in a Cherokee 180 I had almost full rudder in a slip into the
> wind [almost full, remembering a Cherokee has a 17kt Xwind component
> demonstrated] - full flaps and about 1700 or 1800 rpm down the shoot
> at 80mph on short final decaying to 75 over the fence and then into
> rotation speeds at touchdown. Got the stall warning about hairswdith
> off the ground and on we went, low wing first, pivot it straight and
> power off and we are down - more or less on the centerline.
I was personally in an Archer in winds gusting to 45 knots directly across
the runway. I wasent flying or anything. I was just watching my instructor
fly while I was filling a bag with puke. It's always good to know that it
can be done.
John Roncallo
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