• This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn more.
Pumpkin drop event

Plane rolls left when hand launching at 75% throttle

chris398mx

Well-known member
#1
What is it called when a plane rolls left during launch and how do i correct for it. It doesn't seem to do it during normal flight after the plane has some air speed.
75% P40 with an F-pack motor and 3S 850 mAh battery.
 

sprzout

Knower of useless information
Mentor
#2
Ahh, sounds like you're experiencing the dreaded torque roll. Are you hand launching the plane, or are you taking off from the ground?

If you're hand launching, try reducing power to about 50% throttle and giving it a toss to get air moving across the wings. That air movement is what generates lift. If you're just letting the prop do all of the work, the torque from the rotating motor is going to want to roll the plane - it's a major reason why helicopters have a tail rotor, to help counteract the twist of the motor.

If you're taking off from the ground, try rolling up on the throttle and letting the plane get air under its wings before you pull up, instead of going full throttle, hard to the stops. That'll help on the takeoff. My dad experienced the same issue, said his plane kept pulling to one direction, and by rolling smoothly up to full, rather than a "shove it to the stops" approach, helped him IMMENSELY.
 

chris398mx

Well-known member
#3
Ahh, sounds like you're experiencing the dreaded torque roll. Are you hand launching the plane, or are you taking off from the ground?

If you're hand launching, try reducing power to about 50% throttle and giving it a toss to get air moving across the wings. That air movement is what generates lift. If you're just letting the prop do all of the work, the torque from the rotating motor is going to want to roll the plane - it's a major reason why helicopters have a tail rotor, to help counteract the twist of the motor.

If you're taking off from the ground, try rolling up on the throttle and letting the plane get air under its wings before you pull up, instead of going full throttle, hard to the stops. That'll help on the takeoff. My dad experienced the same issue, said his plane kept pulling to one direction, and by rolling smoothly up to full, rather than a "shove it to the stops" approach, helped him IMMENSELY.
Yes, i am hand launching and trying to build speed quickly as the plane is falling and rolling left until i get enough speed to gain some control of the surfaces.
 

sprzout

Knower of useless information
Mentor
#4
Ok, try this:

Put yourself at 50-60% throttle, give a bit of up elevator, and toss it. That should help it from dropping. I've seen guys who have built in a bit of flaperon/up elevator with a switch, so when they launch, it pulls up a bit, and they can then flip a switch and it's off once they're flying normally. I myself am not sure how they programmed it in; I believe it's something with mixing/flaps.
 

Bricks

Well-known member
#7
Plus what was said above give the aircraft a harder toss really get after it to help build speed and get the wings flying, I was bad at this for a while until I figured it out.
 

chris398mx

Well-known member
#8
Plus what was said above give the aircraft a harder toss really get after it to help build speed and get the wings flying, I was bad at this for a while until I figured it out.
I tried your suggestion of throwing it harder and a little more upward and it has helped quite a bit on this model. Thanks for the input.
 

ZOHIO

New member
#9
What is it called when a plane rolls left during launch and how do i correct for it. It doesn't seem to do it during normal flight after the plane has some air speed.
75% P40 with an F-pack motor and 3S 850 mAh battery.
If flying with a friend or spotter, possibly have them walk the plane and then toss it rather than just being stationary. You never know when you could use a bit more oomph. 👍🏻