Qustion/Test for Taildragger Pilots

[Jungle Jim]

Guys,

I was at a Thorp T18 flyin recently and an older guy asked us a question that no one answered correctly and I thought I would ask this group as well.

You are sitting on the runway ready to take off with a very stiff, 90 degree crosswind from your left. What do you do?

Don't be shy about answering.

Jim

[Meatservo]

I AM shy about answering, because it sounds like a trick question. Maybe the correct answer is, "taxi to the end, turn around, and take off the other way". Which way does the prop spin on a Thorp? I'm too lazy to look it up.

[Panama Jack]

I would take the perpendicular runway, facing into the wind. . . but that's just my preference. What did the old guy say?

[who me ?]

What is the cross wind limt on the aircraft ?
What is a "stiff" 90 degree crosswind ( how many knots )
How much time on type does the pilot have ?
How wide is the runway ?
Is runway paved and dry ?

Sometimes it is worthwhile to position the aircraft on the downwind side of the runway,
( if the runway is wide enough ) and take off on an angle into wind to lessen the 90 degree crosswind.

If the Thorp has narrow gear,(?) the "correct" answer might be wait for more favourable conditions ?

[trey kule]

You are sitting on the runway ready to take off with a very stiff, 90 degree crosswind from your left. What do you do?

Take off, of course, unless the condtions have become unsuitable since you taxxied on to the runway. Otherwise you should not have arrived at that position to start with.

I guess there are stupid questions, after all.

[cgzro]

Check your email?

[Nephilim]

Am I missing something here? P factor and torque pulls you left on acceleration so you would always favour a cross wind that counters from the right when given a choice of 90 degree xwind.

Opposite on landing where deceleration occurs especially if turbine powered with reverse, should then favour a xwind from the left on landing.

Safe flying uall.

[Colonel Sanders]

Always take a strong direct crosswind from the right when your propeller rotates clockwise, viewed from behind.

This is to avoid running out of right rudder during full power, which can happen during takeoff or an overshoot from a landing.

It's in the FTM for Christ's sake.

[Jungle Jim]

You guys are pretty good!! The right answer was to taxi to the end and take off in the other direction so the the wind is now on your right side. The wind plus the torque effect as the tail rises causes the plane to steer to the left, which makes it very difficult to handle.

Jim

[cdnpilot77]

Well, it depends, was there a controller giving a last minute wind check?

[gustind]

Well, it depends, was there a controller giving a last minute wind check?

That can be a real game changer right there. Very important to have that.

[Siddley Hawker]

Screw the crosswind, I'm with Panama Jack on this.

[sidestick stirrer]

Is Vmcg affected by a crosswind?
If it is, should you stay on the centerline during takeoff or go slightly to one side?

[Ref Plus 10]

Interesting question, I had never put much thought in to Vmcg in a crosswind. My answer however would depend on the aircraft, so the following will be in reference to that.

In the one I currently fly, Vmcg is well below V1, so a failure of the critical engine would still result in an aborted takeoff (on wheels, anyway). The conditions for Vmc are based on the least favorable C of G, critical engine failed, max gross weight, and flaps in a takeoff position, but there's no mention of crosswinds at the maximum demonstrated crosswind component. I would imagine that in the aforementioned crosswind (presumably from the left, for the sake of this discussion), it would make control more difficult, but not impossible. It is my opinion that if the aircraft were to accelerate with both engines making normal takeoff power, and able to maintain directional control, that should a failure of the critical engine at Vmcg occur, if for whatever reason the takeoff was continued (which it would not be, as this is still below V1, even for our lightest weight), directional control could be maintained.

As for the proposal of offsetting your takeoff run from the centreline (again, only my opinion, not based on fact or science), I believe that this would only reduce your ability to remain within the confines of the runway, should such a failure occur. If it were prudent to offset, what criteria would you use to determine when to do it? Wind velocity? Just out of maintenance?

My three and a half cents worth.

Ref