I am a total drone (and RC) beginner and have been trying to develop a drone that I could use for remote sensing of my remediation sites.
I initially tried to use an X-UAV talon as a first platform, However after a massive crash I realised that I need to start on something smaller and less expensive to crash.
I then chanced on the swappable series from flite-test and then proceeded to build a couple in order to learn to fly. I can now (sort of) fly an aeroplane and so I build a blunt-nose foamboard FT versa to learn to fly on.
Flying a wing is very different from what I am used to so I thought it would be best to do my first flight in FBWA mode so that the autopilot could correct for my mistakes.
It did not work well at all. the plane launched quite well and seemed quite stable initially but then as it banked it went into a spin-dive and crashed.
I have no idea what went wrong and I do not know how to check. all of the control surfaces seem to be behaving properly when I tested it before the flight.
Did you set the maximum bank angle? I set mine to 45 degrees max, and that seems very docile.
Are you using an air-speed sensor? I had problems with one that was soldered slightly wrong. Don't use an air-speed sensor until you have something working well.
Also, when you are on the ground and put it in FBWA mode do the control surfaces move correctly when you tip the plane from side-to-side?
I tested all the control surfaces in FBWA mode on the ground and they seemed to be working fine. I am not using an air speed sensor at present. I would like to at a later stage tho.
I have not set the maximum bank angle or adjusted any of the default settings. I will try and set the bank angle to a lower value and see if that helps.
Is there any way so that I can see if the plane tried to correct when everything went wrong?
Flying wings are never a good idea for a first aircraft. They demand an accurate Center of Gravity to function and if this is too far back then the death stall and spin is the usual result.even with an autopilot (APM) it will not survive or be controllable. Once they are trimmed and set up correctly then they fly very well and are predictable. If you have a skilled pilot to help you then fine, if not then take a high wing bixler or similar aircraft. Then when you have the required skills move to the wing. Best of all get some local assistance (local flying club?)
When you tip the plane in stabilize mode, does the wing that's up have its control surface raise towards you? It's like it's trying to "high-five" you.
Aha! Thanks everyone! that problem is now solved!
I realised that the elevons were not correcting in the correct direction despite the fact that they were moving in the correct direction for FBWA.