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

Take off problem!

#1
Hello ya, How ya doing?

I have problem with take off. Recently I bought a FT Dust (https://store.flitetest.com/ft-duster-speed-build-kit/). I build it correctly and following every step carefully. Before the flight I did everything like range check, power, etc. everything work. The problem is I set the RC airplane down the runway. It did move forward and then to right and left something and crash into sideway. It never go straight. I thought it might be motor but it does move forward. I adjust the tail and everything to correct position and doesnt help at all. Does any know what is happen? How can I fix it so it go straight and take off? FYI : This is my very first fly RC. I like to this RC fly cant wait. and Sorry for bad english I hope you understand!

Thank you for time!
 

pgerts

Old age member
Mentor
#2
It is probably something called "ground loop" and is something you can expect from "taildraggers". That is one reason almost all planes today use a nose wheel - "tricycle". By carefully compensate with the rudder it is possible to start straight but not even all advanced pilot manage.
It you are new at RC i think that most will suggest that you get some help.
Someone to throw the plane, or someone to trim the plane and give you some help how to fly successfully.
 

Bayboos

Active member
#3
There are several steps you can take to (at least try to) decrease this tendency.

First thing to do is to check that both main wheels rotate freely and with no noticeable friction; that they are not too loose (no wobbling) and are straight and parallel (if impossible, a tiny toe-out is better than toe-in).

If you can modify your landing gear, spreading main wheels further apart and moving them back (closer to the actual CG) usually helps a bit. If you can (and are willing to) replace the landing gear, try to make it stiffer. There are several ways to do that; but the most common and the easiest to apply are: using thicker wire (obviously), strenghtening the L/G legs (by glueing something to them, e.g. BBQ skewer or another wire) or making them shorter (not always possible, but worth trying).

And finally, proper take-off technique can help, too. What you want is as much airflow over the vertical stabilizer as soon as you can get it. That means applying full power with one quick (not neccessarily immediate) move. If this is causing the plane to immediately turn one way, counteract it with full opposite rudder for few seconds; you should not need that anymore as soon as the plane starts picking up speed. If your plane have tail wheel that is either connected to the rudder or always straight (not moving freely), you should not use rudder at all - rather than that, use elevator to keep the tail on the ground. Again, you should do that for few seconds only; you definitely don't want the plane to lift off with elevator in full back position.

The technique described above may not be valid in one case. If you have very powerful motor installed, the torque effect may be a problem as well. It is actually quite easy to recognize - if the airplane starts moving at 1/4 of the power and is going perfectly straight (even if it's going too slow to fly), too much power is most likely the cause of your troubles. In that case, it may be actually better to apply power slowny and gently, going from zero to full power in 10 seconds or so; or even not applying full power at all until the plane is airborne.

And there is one more thing, specific to your plane. FT Duster have a huge canopy ("head") that is disturbing the airflow. A LOT. Try to fly the airplane without the canopy at all, and see if that helps.

Good luck, and have fun!
 
Last edited:
#4
Thank you for rely, I try to do as much as I can. FYI: I did take off head to try if that cause the problem but no it still have same problem. Is there anything else should I do?