When taking off with a prop plane should I set up the ailerons so that I have a little up on the right aileron and down on the left to compensate the plane from going left due to torque

No.

That's the function of the rudder. Leave the ailerons alone. In fact, for your very first flight with the plane, the ailerons should be as straight as possible, meaning no up or down on either side. Neutral, in other words.

CGr.

Yep... to clarify CG's (very correct) assertion - yes the plane may roll to the left on takeoff. This is due to the plane's reacting to the torque of the prop, however the correct way to fix it is with the rudder. The prop's torque will attempt to yaw the plane to the left which will then induce a roll. If you counter it with the ailerons you're countering the symptom, not the cause. Use a little right rudder on take-off - the plane will settle down and flight straight once it's up to normal flight speed. (That's not to say you should trim your rudder right - just use the stick. If you trim it to the right you'll be fighting it the whole flight.)

Thanks, Sandmann.. I'm still trying to wake up..

CGr

Yer welcome.

There is actually a very simple way to solve the left-hand roll/turn that happens on takeoffs.

Learn to control the model's acceleration on takeoff. Learn to roll into the throttle only as fast as the airplane wants you to. That's one of the two primary considerations to takeoff safely. Steering with the rudder and sensibly controlling throttle together are an unbeatable combination.

The prop is working almost 100% from the time it taxiis the airplane. The airframe isn't even close to flying until it's got some speed. The prop has no problem steering an airplane that isn't capable of much steering at all. The wing might not even be past stall speed. The stabilizing structures aft are barely working and certainly with very little power. And you suddenly slam that throttle up to flat out speed.......... bad idea that's proven to be a losing situation almost every day.

Proper use of ailerons to counter a cross wind is required when the wind is not straight down the runway. Not understanding this is just as bad as not properly controlling the rudder.

G'day Mate,
It sounds to me like you have never flown before, if that is the case, GET AN INSTRUCTOR, or at least someone with some flying experience, to help you.
If you decide not to get help, then take a garbage bag & a camera, so you can collect the pieces, after you take some pix to show us your handy work.
Have a great day.

A little harsh......
..................But fair, I thought

ANY roll function requires input from the ailerons. His post sounds more like he's still on the ground and not yet airborne. If that's the case, aileron input can be a tad bit error prone.

When taking off and landing, use the rudder to make directional corrections. When you are approaching or leaving the ground, ailerons are just to keep the wings level.

All of which takes us back to correct take-off procedure. A torque roll on take-off is usually caused by too much power when moving too slowly, causing the plane to "jump off" the strip (the weight hanging from the prop) instead of "flying" off (the weight sitting on the wings), which in turn causes yaw, which induces a roll, as both DaRock and CGR pointed out. The correct method is to slowly & smoothly apply power allowing the plane to build up speed while the weight's still on the wheels. If it's a taildragger you then "fly the tail" while still smoothly increasing power (ie: use the elevator to keep the plane level with the mains still on the ground). Only when the plane has reached flight speed to you rotate it for a smooth lift-off with a gentle slope.

If it all goes pear shaped and the plane takes off using engine power for lift instead of airspeed over the wings the chance of a torque roll is high and you should be ready on the rudder to keep the plane straight. Because the flight surfaces won't be working at anywhere near full efficiency at this speed you don't want to let it get into a roll that'll be hard to recover from - you want to keep it tracking straight so it doesn't get to roll in the first place. The reason the plane starts to roll is because when it begins to yaw the wing on the inside of the turn is moving slower than the opposite one, which means it's generating less lift so it drops the wing.

If you forget/were too late/etc with the rudder and the plane DOES roll, then your only alternative is to use the ailerons to level the wings before it rolls too far and tip stalls (remembering we're not really at flight speed and the wings are barely working). What you DON'T want to do at this point is slam the stick over to the right in a panic - we're not trying to execute a fighter turn, we're simply keeping the wings level. Keep your right rudder going and give the ailerons a twitch of right stick just to pull it inline. If it's a good day it'll level out and get up to flight speed. If it's a bad day you'll be looking for a garbage bag to put your plane into. Thankfully there's more good days than bad ones.

If you find that on most/all take-offs you're having to correct rolls I'd suggest some practice time doing high speed taxi-ing. Line your plane up on the runway and start your take-off procedure, but don't let it get off the ground. When you're 1/2 - 2/3 down the runway (depending on how long your runway is) smoothly cut the power and abort the take-off. Turn the plane around and try it again. You want to see how fast you can "drive" your plane along the ground without it lifting off. (This should probably be done on a really smooth grass runway or even better a paved one in good condition. Don't try it on your local park as too much rough ground at high speed will have you repairing your undercarriage.)

From your reply, I'd guess that you do not understand the proper use of ailerons during a crosswind takeoff either. Yes, while still on the ground!

Well, you go right ahead and do what you wish. I'll continue to do as I have always do, and not use the aileron on the ground. So far, I've not had a take off that was defective in any way shape or form in just about any wind condition the way I've been doing it. Of course, this changes as soon as the wheels leave the ground, which may be what you are talking about, but I usually keep at least the two main wheels on the ground during the roll-out when lift takes over. Then I control roll and the yaw with both ailerons and the rudder.

The proper use of ailerons when taking off in a crosswind is to use them to give the airplane a very slight roll into the wind. The idea is based on the effect that is used by airplanes designed with dihedral like our rudder/elevator gliders. The idea is often described as keeping the upwind wing from presenting it's underside to the gusts. In fact, it's mainly to keep the AOA of the upwind wing from creating unwanted lift from the gusts. The recommendation is to hold a bit of aileron into the wind. It's a suggestion to hold a steady amount of "trim" that's easily and quickly removed without having to do anything more than slightly moving your stick.

It does not contradict the idea that sudden attempts to steer an airplane in the midst of taking off increases the possibility that excessive aileron deflection of a wing already close to the stall would be stalled by that deflection.

The reason it's suggested to NOT try to steer your airplane off the runway with ailerons, to use the rudder, is because of the rudder doesn't increase the probability of a wing stall as quickly or easily as increased aileron deflection does. It's safer to steer your airplane on takeoff with the rudder. From the start of the takeoff roll until the model is safely airborne.

If you're a beginner who wants to succeed at your new hobby, it's really a good idea for you to learn to steer your airplane on takeoff with your rudder instead of the ailerons.

I still don't know if he's taking about when the plane is on the ground or when it is just getting airborne, pretty essential for the answer I think...

His original question sounds like either of two......... dial in aileron trim before rolling, or hold aileron before rolling. The wording, "setting up" suggests it's done at leisure beforehand. Of course, the detailed account of which aileron up AND which down confuses even more. After all, experienced modelers wouldn't feel the need to explain aileron trim that is done with a click of the trim button.

Neither is needed and both will cause problems in more situations than less. And trimming ailerons beforehand certainly isn't needed either. So before or during, neither is needed.

Beginners really shouldn't look for crutches for a maneuver that is so easily controlled with the proper technique.

Learn to ease in the throttle and steer with the rudder. It saves you so many airplanes.

Yeah, that was my point. It wasn't clear if he was talking about on the ground or just as the plane lifts off. The aileron is pretty much ineffective on the ground, well, for flight I mean.. it will cause the plane to tend to "roll" even on the ground with enough speed on. But as soon as those wheels leave the ground, then the ailerons are doing their thing and it comes down to control and gaining height in a straight line.

CGr.

An adequate explanation:

http://avstop.com/AC/FlightTraingHan...keoffroll.html

Unless you plan on only flying when the wind is straight down the runway, you should learn the proper techniques.

A little story:
I used to be a member of the Popular Flying Association, the UK equivalent of the EAA.
I used to attend the group ("strut") meetings at Andrewsfield near Stansted Airport.
One night there was a fellow there with a horrifying injury to his forehead; a dent that you could fit a dollar piece into.(he was still flying though!)
The story was that on a cross wind take off in a Tiger Moth at Stapleford aerodrome (also near Stansted) he had lifted off, swung into wind with rudder and aileron then touched down again. Now going sideways, he had wiped off the unercarriage and then crashed on the downhill bit of the runway, skating into the aircraft parking area, complete with parked aircraft. He shot forward and removed part of his brain on the E2b compass.

The bit in that article about skipping sideways reminded of that.

It turned out later that evening that, of the 12 pilots there, I was the only one who hadn't actually crashed an aircraft!

Recently I got a .25 class old low-wing trainer, I put a .32os on it ,I did set 3 to 5 deg offset on thrust line to the right,but when taxiing on ground ,just a little advance on throttle will cause obvious yaw to left , So a lot of right rudder is required before it get airborne ,when airborne it has very strong tendency roll to left .I used a lot of right aileron to counteract the roll to keep wings level ,what should I do?increase riht offset or ?

Are you sure you put the right thrust angle in? Should be a couple of degrees to the right (as if you were sitting in the cockpit).

I have a tail dragger, its a P-51 and for take off of any tail dragger you have to ease the throttle up while adding right rudder (not too hard b/c throttle and rudder are the same stick) untill the tail comes off the ground (once that tail is off the ground then the vertical stab is more in control and will help to keep the plane from ground looping) then you can ease throttle up to take off power (mabe full?). It is just those critical moments when you are adding power while the tail wheel is on the ground that you need to input right rudder...that will allow your plane to keep a straight path down your runway try that and you will A-OK. With my P-51 I've learned (and i learned quick just taxing fast around on the runway) that for take off I start with about 1/4 right rudder then add power... with your plane you will have to figure that out. More than anything just remember to have fun and enjoy that plane!

The main thing for take-off of any airplane is that the controls are constantly used to make corrections as the take-off progress. The most demanding on the pilot are tail-draggers, though having the model properly set-up with regard to engine thrust line, main gear location (depending somewhat on type of runway - grass or pavement) and angle of attack make a big difference in difficulty.

When first starting the take-off roll, more or less into the wind, you hold up elevator and right rudder as required to maintain directional control. As the model begins to roll, back pressure on the elevator is relaxed as the model picks up speed, all the while using the rudder as required. The goal is to get the tail of the airplane in the air (it's flying while the airplane is still on the ground). At this point, much of the rudder required initially has been relaxed, and the airplane steers on the ground about the same as if it had a nose wheel. Allow the airplane to continue to build speed until it achieves flight speed. Often, the model will just lift off, but you can also use a slight amount of elevator to increase the angle of attack on the wing and it will lift off.

Making the take-off more difficult are cross winds, wind that does not align with the runway. This can cause problems through all phases of the take-off, since the model may want to weathervane into the wind, even to the point where you may even be using left rudder to hold the model on the correct heading. But be aware, the torque from the engine is very powerful, especially with larger low pitch props. So you can not freeze on the rudder, it takes a soft touch and constant adjustment.

As far as use of the ailerons into the wind, you start off with full aileron at the beginning of the roll, but by the time you have reached flying speed, nearly all the aileron control input has been removed since the ailerons have much more effect as the speed builds.

Master all these control inputs, by doing lots of take-offs in various conditions. But with some work at this, you will be amazed by your growing expertise, and will be ready for any model you want to fly.