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gulfcoastfella
12-03-2004, 03:18 PM
I don't know if my plane is supposed to be doing this or not, but when I try to land at the airfield in the "Carrier Takeoff training flight" my plane yaws hard right. I try to compensate with left rudder, but it doesn't help, the yaw is way too strong. Are there separate keys for each wheel brake which I can use to steer the airplane? If I can't figure out how to control the yaw, I'm going to keep running off the runway and flipping my plane.

9th_Spitin
12-03-2004, 04:13 PM
You are experiencing torque effect. Read this article, it will help explain. Torque effect (http://www.aerospaceweb.org/question/dynamics/q0015a.shtml)

Athosd
12-03-2004, 06:28 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by gulfcoastfella:
I don't know if my plane is supposed to be doing this or not, but when I try to land at the airfield in the "Carrier Takeoff training flight" my plane yaws hard right. I try to compensate with left rudder, but it doesn't help, the yaw is way too strong. Are there separate keys for each wheel brake which I can use to steer the airplane? If I can't figure out how to control the yaw, I'm going to keep running off the runway and flipping my plane. <HR></BLOCKQUOTE>

It may also be due to a strong cross wind - is there turbulence below ~300m?

Try landing on a strip in the QMB (Quick Mission Builder) with clear weather. If you don't experience the same yaw effect as in the "Carrier takeoff training flight" it is most likely due to atmospheric conditions.

Cheers

Athos

gulfcoastfella
12-03-2004, 08:05 PM
I read the recommended article on adverse yaw and have determined that adverse yaw is not the problem. The reason I say this is because after I touch down on the airstrip, I no longer use my ailerons... I only use my rudder to control the airplane. Since adverse yaw is due to aileron deflection, I've concluded that my yaw problem is not an adverse yaw problem.

I found an article about gyroscopic effects located on the web at http://www.exploratorium.edu/snacks/bicycle_wheel_gyro.html. This article does a good job of explaining how a rotating mass (the propeller) can cause a yaw about an axis perpendicular to the mass's axis of rotation (the roll axis of the aircraft).

The thing I still don't understand is why the gyroscopic yaw is so strong when I've throttled all the way back upon touchdown on the airstrip. Should I perhaps feather the propeller? I'll try this in the simulation and see if it helps.

Jetenginedr
12-03-2004, 08:15 PM
did you apply rudder/aileron trim when the engine was on power to come in straight and level?
Maybe when you throttled back the torque dropped significantly while your still trimmed for power.

Athosd
12-04-2004, 12:32 AM
Which Takeoff Landing mission (Nationality) are you flying - and which aircraft?

It is a bad idea to zero your throttle as soon as you touch down.
Try to touch down with throttle at about 15 - 25% (speed depends on type but usually around 140-160kmh is okay). Raise you flaps immediately (improve stability and reduce lift) and use a little up elevator to get the tail wheel down, if necessary. Pump the brakes - standing on them will just put you on your nose.
Gradually reduce throttle as you taxii to a stop. Use rudder as needed to stay on track.

xTHRUDx
12-04-2004, 12:48 PM
the original poster is correct. many times online, i come in fast to my field (no matter the plane) and kill my engine and glide in an attempt to slow down quicker. durring the touch down i get this strange pull to the right. very annoying. it's like the modeled torque effect doesn't know that my engine is off.

Korbelz
12-04-2004, 03:34 PM
if you touch the brakes with any rudder in at all at high speed if will feel like you are pulling to the right/left because thats how you use each right/left brake.

gulfcoastfella
12-06-2004, 01:41 PM
<span class="ev_code_RED">Korbelz</span>, Thank you so much! I've been trying to find out if it was possible to separately control the brakes on each wheel. The game manual doesn't say anything about it; neither does the game website. I'm sure your advice will solve the yaw problem and give me control over my plane again. Once again, thank you!

Fliger747
12-06-2004, 01:52 PM
Typically one will have a lot of right rudder trim cranked in for takoff. It is necessary to remove this for a power reduced landing such as on an airstrip. For a carrier landing when a lot of power is carried at low speed to the cut, generally it stays in there and the hook straightens you out.

Trim rule #2: Right rudder trim with high power, left rudder trim without.

Good luck!

xTHRUDx
12-06-2004, 09:59 PM
i'm surprised none of you have tried my test. take a single engine plane (any) and do a dead stick landing from 1000m. there is a bug.

Fennec_P
12-06-2004, 11:35 PM
take a single engine plane (any)

Can you be more specific? I can't replicate this.

With Yak-7a or 109G2 at least, there is nothing unusual when performing engine-off landing.

I also tried the carrier takeoff training flight #1 (USN), and there is nothing unusual about the landing there either.

On landing, there is a small crosswind from left to right. But the yaw is negligable and easily compensated for.

xTHRUDx
12-07-2004, 12:17 AM
the cross wind effect is what i'm refering to. having the engine on when landing cancels this "effect" out. like i said a few posts up, it's like the modeled torque effect doesn't no my engine is off.

Fennec_P
12-07-2004, 01:23 AM
No, I mean there actually is a cross wind on that mission.

But you're right, there does seem to be a small torque effect across the board. From the description, I was expecting something much more severe.

I try to compensate with left rudder, but it doesn't help, the yaw is way too strong

I mean, this effect is virtually nothing.

J_Weaver
12-08-2004, 09:52 PM
I've noticed this. It doesn't happen to me all of the time but sometimes I just can't keep a plane on the runway, takeoff or landing. Good or bad weather. Sometimes it seems bad other not so bad.

Tully__
12-08-2004, 10:10 PM
I've never seen it, though in trying to replicate it I noticed that the P-40E has really good low speed energy retention even with full flaps & gear...overshot two consecutive dead stick landings http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif.

effte
12-09-2004, 05:47 AM
Torque will only cause yaw when you change the pitch attitude.

Lots of people throw the term 'torque' around very carelessly, seemingly as a standard explanation for any yaw created by effects related to the propulsion.

Edit: And I add myself to the list of bloody stupid people using torque as an excuse for everything. Torque will not cause yaw, period. Torque will cause roll. Gyroscopic precession will cause yaw when changing pitch attitude.