Ogriv

I am still on the buddycord system, but have advanced to take-off's and landing without assistance. When I am taking off my plane wants to steer to the left. When I give it full throttle, it really wants to go left. I believe this is an effect of the engine. What is the best way to counter this? Perhaps set the nose wheel off-center towards the right? I currently have my wheel centered.



Any advice is apprieciated.

tonyc

My Feedback: (4)

This is common and a part of learning to fly.
Do not "off set" the wheels. This will only creat other problems.
What you need to do is use the rudder. Start out with a slow roll down the center line of the landing strip. A slow start will have less of a pull to the left, fast starts can pull you quickly left. Watch to see what the plane needs, feed in some right rudder as the plane needs it. Your goal is a smooth straight roll down the runway.

Keep the rudder input in even after lift off, if the plane needs it. The goal here is to keep the wings level and the airplane flying straight.

Just takes a little practice. Remember slow starts are easier.

tonyc

gus

The torque of the engine causes the plane to yaw left. To counteract this, you can do a few things:

1. Input (small amounts of) right rudder
2. Apply the throttle more gradually on takeoff.
3. build a couple of degrees of right-thrust in to the engine mount.

The basic premise is that with the revolving propellor generating thrust, there is a counter-force (newtons laws of force - every action has an equal and opposite reaction), and that counterforce of the revolving prop is yawing the plane. This is very normal, and the common consensus is "learn to deal with it".

I'll edit this post to add a few links.

gus

P.S. Here's a good link [link=http://www.rcuniverse.com/forum/m_290989/mpage_1/key_torque%252Cthrust%252Cright/anchor/tm.htm#290993]Aerodynamic discussion of right thrust[/link]

rc-sport

My Feedback: (12)

Ogriv, double check that nose wheel and make sure it isn't flexing to the left when its running down the runway. Nose gear planes are normally more stable on take off than tail draggers. Use your rudder to compensate the left pull but DON'T hold right rudder after it leaves the ground, you'll roll the plane right in. Advance the throttle slowly, slamming it to full throttle will only increase the torque action.

FLYBOY

My Feedback: (11)

As stated, add the throttle more slowly and learn to use that left stick to keep it straight. It will make you a better pilot.

MadScientist

Get another instructor that knows what the left stick is for. Just asking this question shows that your instructor is not covering all he should. The above advice is what you need to do though.

MinnFlyer

My Feedback: (4)

One other thing you COULD check is to roll the plane (Engine Off) on a flat surface, and make sure that it rolls straight to begin with. If not, adjust the tail wheel. But if it does, then start working that rudder on takeoff (Which you'll need to know anyway if you ever fly a taildragger).

jetmech43

My Feedback: (9)

its called p-factor is normal just apply more right rudder

iowanspctr

The p-factor is totally correct. To expand on it, it's because the propellor blade going down pulls harder than the blade going up, at least relative to the ground. A little right rudder corrects for it and it's just part of what you have to learn. Full scale is the same, it takes a little right foot on take-off to keep straight.

LearjetMech

I thought P-factor was only relevant in a climb or high angle of attack! I believe this is actually called Gyroscopic procession!

iowanspctr

A take-off, by definition, would involve a climb. Even if a plane was mis-rigged so as to be nose down, as soon as the nose was pulled up to take off, p-factor would become dominant. Given the relative masses involved, I don't thnk precession has been very important since the days of the rotary engines in WW-I. It was very important then! Thats part of what made the Sopwith Camel so maneuverable, though only in left turns. But that involved the whole engine and propellor assembly revolving about a stationary crankshaft. Much more relative weight than a crank and prop.

randy41

If this is a trainer plane i would be looking
in to the mechanics of the nose gear
or a miss alinged engine. I have flew many
trainers and havent had that severe of
turning problems on take off due to engine torque.

tiggerinmk

A while ago, an excellent article appeared on the HH site titled 'The 5 evils of popellers'. Unfortunatley, it has been removed. I might have a copy somewhere. However, all that technical mumbo jumbo is irrelevant when the aircraft is still on the ground and shouldn't make much difference on take off.

Assuming its a trike gear, the most important (and often overlooked) thing to check first is that the plane tracks straight on the ground with the rudder centered.

Do some taxiing tests at various speeds with the wing off until you are confident in steering the plane around and are sure that the plane runs straight with the left stick centered.

The plane should now run straight until it gets close to flying speed. If the plane then veers to one side and you've eliminated the simple possibilities such as a cross wind then you can start lookng at the more esoteric options.