Unexpected Motor Shutdown During Stable Hover

ArduPlane VTOL Plane
1

The vehicle was hovering normally, vibration levels looked fine. Then, whole motor suddenly stopped spinning completely. In the .tlog, the RC Channel 3 (Throttle) jumps to full for about 0.4 seconds and then drops to zero at the exact moment of failure. Voltage and current readings look stable before the event (no significant sag visible).

Setup Information

  • Flight Controller: SpeedyBee F405-WING
  • ESC: T-Motor V50A SE 4in1
  • Motors: T-Motor F90 1300KV x3
  • Receiver: RP3 ELRS 2.4GHz
  • Radio: Radiomaster Boxer
  • Battery: 6S LiPo 6300mAh
  • Firmware version: ArduPlane 4.5.6
  • Protocol: PWM (DShot not used)
  • Telemetry: MicoAir LR24-F 2.4GHz

Itā€™s the second crash with the same symptom.
I even added new capacitors thinking it might be a power issue, but it crashed again.

After the last crash, the calibration on esc has gone awry. This time, too.

Could this kind of motor cutoff happen because of BLHeli desync when using PWM instead of DShot?

Hereā€™s my tlog, param and crash video. I have no idea what the problem is. Itā€™s my college graduation work. Please help me :sad_but_relieved_face:

2025-11-09 09-04-46.tlog (677.0 KB)

motor_stop_param.param (22.5 KB)

Takeoff at 09:06:46 and crash at 09:08:22

https://drive.google.com/file/d/1gSIXSAIkk3ID6mKAkkGK5_5BpKIIszhd/view?usp=sharing

2

Can you post the .bin log file of the flight? That will be better to look at than the .tlog.

1 Like
3

Sorry I only have tlog..I didnā€™t know that the tlog didnā€™t have much information. So I didnā€™t put on the sdcard. Please let me know if you need any more information.

4

How is your ESC cooled. It might be simplly over heating and to prevent damages on electronic simple shut off.

1 Like
5

After exploring all day, I think youā€™re right. Thereā€™s esc in the fuselage, and thereā€™s only a small ventilation hole in the nose and tail. So it doesnā€™t seem to be cooling during hovering. Do you think heat sinks and cooling fans will work?

6

ā€¦ā€¦ā€¦ā€¦ā€¦..[
quote=ā€œhtk0484, post:3, topic:140769ā€]
So I didnā€™t put on the sdcard.
[/quote]

Never do that.

3 Likes
7

Sounds like a thermal protection in the ESC. I always disable mine, and current.

.bin files are crucial in diagnosing these things.

Check my post about VTOL cooling.

1 Like
8

I been testing a new FC and this radio have made some odd issues. Not saying this is your issue But I would try the mRo ones as an alternative.

1 Like