Hey guys, I have a FT trainer plane that’s been doing some really weird stuff. I recently graduated from the FT explorer to this. I made it a few days ago and every time I fly it it starts to sway back and forth a lot! I will try to post a video if I can but for now I only have a pic of it. Btw I’m a beginner
Need help with plane!
- Thread starter NicCf1
- Start date
Foamforce
Well-known member
Possibly tail heavy? I notice that you moved the servos to the back which would make it more tail heavy than the original design. That should also make it pitchy (up and down quickly). Is that what you’re seeing, or only left to right sway? If only left to right, then maybe loose control rods?
I’ve also head of something called Dutch Roll which sounds like what you’re describing, but I’ve never seen that on a Tiny Trainer.
I’ve also head of something called Dutch Roll which sounds like what you’re describing, but I’ve never seen that on a Tiny Trainer.
Piotrsko
Master member
My SWAG from the video: horrendous prop for such a small plane, looks like you arent actually flying as horizontal helicoptering. The wag seems to be tip stalls. What effect does full down trim have?
<ctr><alt><del>.
Take prop off and fling it couple times as a glider to get CG correct, you should end up with 50 ft of glide in a straight line when it's set correctly. Check the current cg, suspect it balances behind the high point of the wing
<ctr><alt><del>.
Take prop off and fling it couple times as a glider to get CG correct, you should end up with 50 ft of glide in a straight line when it's set correctly. Check the current cg, suspect it balances behind the high point of the wing
I only have that prop and a 5-inch prop. No in-between and the 5 in barely works.
Shurik-1960
Well-known member
1. You have a rear alignment. The CG should be 25% of the wing chord, from the leading edge of the wing. 2. Once I had screws of the same size 9050, when I needed a smaller size, I took pliers and bit off 5-10 m.After that, I made sure to balance the screw !!! Put two index fingers under the wing on both sides and determine the position where the plane will be strictly horizontal - there is your insisted CG network. 3. For the new model, I measured 25% of the chord on the wing of the fuselage with a ruler and put a pin with a round head on both sides. Then I put my fingers on the head of the pin and by shifting the battery I achieve the perfect alignment of the model. 100% of all models are flying, it remains to trim slightly on the roll and on the elevator.
Ok, what do you mean by "It remains to trim slightly on the roll and on the elevator"?
quorneng
Master member
NicCF1
You need to get your FT trainer "sorted" before you build another
Getting a good test glide will most likely completely solve your problem
When you have a good steady glide use just 1/4 throttle. Such low power may only "extend" the glide but it should still fly the same although it may turn slightly from the motor torque. Increase the throttle a bit in stages until it is maintaining or climbing gently then you can control the plane with small stick movements to keep it within the field.
Doing such a test programme will teach you what you have to do to "set up" a plane so it flies properly. Then you can build another plane although you will likely have to do the same sort of set up process for it to fly properly,
You need to get your FT trainer "sorted" before you build another
Getting a good test glide will most likely completely solve your problem
When you have a good steady glide use just 1/4 throttle. Such low power may only "extend" the glide but it should still fly the same although it may turn slightly from the motor torque. Increase the throttle a bit in stages until it is maintaining or climbing gently then you can control the plane with small stick movements to keep it within the field.
Doing such a test programme will teach you what you have to do to "set up" a plane so it flies properly. Then you can build another plane although you will likely have to do the same sort of set up process for it to fly properly,
Foamforce
Well-known member
Oh yeah, too slow, stalling left and right. I think you can make do with the prop, although it’s making it harder on you.
The biggest immediate change you can make is to try to find a bigger and more open field. You want to get wayyy up in the air and have lots of space to make mistakes and maintain a higher speed. To your credit, it’s surprising that you managed to keep it in the air that low and that slow for as long as you did. 👍
So yeah, make sure your center of gravity is correct first. Try a smaller prop if you can. But definitely find a larger area, at least for your first several flights. Fwiw, my first flights were at a double soccer field, but it wasn’t nearly enough. I started to succeed after I moved to a flying field on top of an old landfill that didn’t have a tree or structure within 1000 feet in any direction.
The biggest immediate change you can make is to try to find a bigger and more open field. You want to get wayyy up in the air and have lots of space to make mistakes and maintain a higher speed. To your credit, it’s surprising that you managed to keep it in the air that low and that slow for as long as you did. 👍
So yeah, make sure your center of gravity is correct first. Try a smaller prop if you can. But definitely find a larger area, at least for your first several flights. Fwiw, my first flights were at a double soccer field, but it wasn’t nearly enough. I started to succeed after I moved to a flying field on top of an old landfill that didn’t have a tree or structure within 1000 feet in any direction.
Aireal Anarchist
Elite member
tail heavy...adjust your cg ...not enough thrust
