Problem with tiltrotor tricopter-plane


I have build quadplane - flying wing (2m, 60dm^2) + tricopter with two front tiltrotors
Total weight - 4kg
engines: SunnySky X2814 with APC 11x5,5 - max thurst 3x2330 ~7kg,
Battery - Liion 4s 6p - 18Ah - 120A max countinous,
ESC - Hobbywing 40A (max 50A).

On 20% throttle plane breaks off the ground but its hard to fly higher - like it dont react on throttle position.

What could be issue of this behavior?
Maybe 4s Li-Ion is not enught?

If you do not hear the motor rpm increase as throttle going up it might be a calibration problem of the esc , check also in your logs if your throttle pwm output at max is around 2000 if not check your radio setup and do a new radio calibration in Mission Planner.

radio and ESC calibrated, also tested in high and intermediade timing. It looks like soft wouldnt let plane take off higher…

Are you taking off in Qstabilize mode ?

Yes - in Qstabilize mode

I’m having a issue with a BlHeli Esc a Hobbywing 35A X Micro .

No way to pull out full power from the motor , max was around 65 - 70% while with a “normal” airplane esc I got full power.

  • What’s your motor kV?
  • LiOn battery typically have very low C rating. Based on your info, at best your pack is 6C at best. Wouldn’t surprise me if your setup is pulling 15+C to lift 4kg.

Good luck.

motor 1000Kv
Battery have 20A normal current, so total 120A

It can be problem with ESC - I found this on you tube:

I will try to flash them - blheli? simonk? any advice?

  • SimonK works for me.
  • Are you sure it’s 20A and not 2.0A or 2000mAh? A car battery is 85A (just for comparison).
  • A quick plug into eCalc shows your setup has 1.4 thrust-weight ratio with 68% throttle to hover at 64amp draw. Have you tried using a LiPo battery instead?

Good luck.

Im usiing Li-ion :

datasheets says 15-22A

In different projects they work well…

Anyway I will try some lipo before flashing…

20A is not the “normal” current it is the VERY max current the battery can hold for a little time and if you translate that in C terms , it is just 6,66C of discharge .

But at 20A that battery will become VERY hot and will provide energy just for 6 minutes not the expected 9 minutes. Consider also that with high discharge rate the tension will be quite low.

If you tell me your AUW and the prop diameter I can tell you more

It is indeed could be a battery issue. Just for the sake of testing, put in some LiPo (less or equal weight) and do a test with it.

I will try on lipo 8Ah 4s tommorow. I will let you know results. Thanks for help!

You had right - problem solved. Now for PIDs time… In copter mode there is only P to change? is it correct?