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Flight control position during taxi

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Flight control position during taxi

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Old 16th Oct 2008, 08:31
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Flight control position during taxi

Hi there,

What is your perspective of positioning the flight controls for existing wind? Where I work, we teach to position them for any wind - even 230 @ 4 kts. Both taxi and take-off. I suspect it is to make it a good habit. Do you think it is overkill and can even have some adverse effects?

Also to be honest, I don't quite understand the taxi diagram in the POH of the aircraft I fly, Cessna 172. The flight controls are positioned to provide the best of directional control. Let me explain:

A strong quartering tail wind situation, for instance. Ailerons "away" from the wind. Elevator down (acc. to POH). In order to get the best directional control, we want weight on the nose wheel to give it authority to steer our aircraft. If the elevator is down, the wind component will act "from above", push down on the tail and pivot the aircraft around its main wheels which will tend to lift the nose wheel off the ground.

...or am I totally missing the point with the wind correction?

I am new to this job, you should know.

Brgds
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Old 16th Oct 2008, 10:04
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The position of controls while taxiing is intended to improve control on the ground and in extreme circumstances stop the ac tipping over, especially a light tailwheel like a Tiger moth. If you taxi downwind with stick back you increase the chance of lifting the tail and dinging the prop. Even on a nosewheel the pressure may reduce clearance enough to be a problem Likewise the aileron position reduces the tendency for the upwind wing to lift causing the downwind wing to hit the the ground.

It matters loads more on tailwheel ac but if we teach the good practice, as your school does, of control position on the ground (climb into wind, dive away from wind) they will think about it more when they get onto trickier stuff.

The POH may give some indication of where to put the stick as you have found. Some books do not advocate pushing the stick all the way forward, just holding it neutral downwind. There is also a rumour that it doesn't matter where you put the stick in a Pitts because the wing loading is so high.
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Old 16th Oct 2008, 12:38
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Yup - wot he said (18Greens)
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Old 16th Oct 2008, 21:47
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In order to get the best directional control, we want weight on the nose wheel to give it authority to steer our aircraft. If the elevator is down, the wind component will act "from above", push down on the tail and pivot the aircraft around its main wheels which will tend to lift the nose wheel off the ground
You want to keep the tail down when taxiing with a tailwind. You want to prevent the tail from lifting the main gear of the ground and "wheel barrowing" along on the nosewheel.
remember you still have steering capability with differential braking, not nosewheel only.

Short answer:

Head wind = flightcontrols into the wind.
Tail wind = flight controls away from the wind.
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Old 16th Oct 2008, 22:40
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Quite right B2N2

I was taught

Climb into wind (Headwind)
Dive away from wind (Tailwind)

This is what I teach my students
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Old 17th Oct 2008, 05:41
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Thank you for the replies! It all made some sense, I obviously got it backwards that you wanted to be nose heavy.
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Old 19th Oct 2008, 10:44
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B2N2

Only partially correct.

If your forward taxi speed is equal to or more than the prevailing tail wind then it reverts to controls into wind.
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Old 19th Oct 2008, 11:03
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Hudson that's just being pedantic.

Face it, a wind less that 10kts is not going to flip over the a/c, and who is going to taxi at 10-20kts? Not my students that's a dead cert.

There's always 1
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Old 19th Oct 2008, 17:30
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And if you want to make it really complicated the prop blows air over the tail.

So when does the tailwind overcome the propwash?
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Old 19th Oct 2008, 20:13
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Uh...flightcontrols into the wind..or away...
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Old 19th Oct 2008, 23:14
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Flight controls

1959, first flying lesson - Piper Cub L-4... Powerful 65 horsies...
No electric starter... and converted gasoline to a litle bit of noise...
Instructor told me, to always taxi with stick "against my tummy"...
With the tail bouncing around, same, to prevent elevators from bouncing.
Was a grassy airfield.
If the wind was from the left, stick back (again) and full left.
If the wind was from the right... same, and full right.
Back then, they were teaching good habits...
And learning to fly the "other kind" (tricycle) took 35 minutes of dual...
xxx
That is almost 50 years ago.
In a lightplane, any lightplane - I still do the same, stick or control wheel...
Nobody ever told me to do any other way. I still fly Super Cubs at times.

Happy contrails - va va voom...
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Old 20th Oct 2008, 16:19
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'Climb into wind, dive away'
'Climb into wind, dive away'
'Climb into wind, dive away'.......
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Old 21st Oct 2008, 05:40
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If it's gay (up yer bum) - push it away.
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