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Pumpkin drop event

Arduplane engine pulsing (no airspeed sensor fitted)


Junior Member
G'day all I'm really hoping some jet here can help me sort out an issue i have when helping a buddy and something I've faced previously in my own projects and not been able to resolve.

I am assisting a fellow flyer to setup an APM running the latest firmware in an FX61 Phantom.

We've found that in RTL or Loiter and I suspect other modes that we didn't test, the throttle is pulsed for what we discovered to be the parameters set as Max 80% and Min 40%.

I had this issue with a previous model but did a fresh firmware update and it was solved. In this case I'd like to learn a thing or two if possible.

Can anyone tell me why this is happening and how we can get it to average out and just cruise?

My initial though is to set the Throttle Min to a few % over the desired cruise %, thus it will just hum along using elevator to manage altitude. We are yet to test this theory so any other advice would be much appreciated. I did this with my previous model I had this issue with and the downside was that if I wanted to land in Stab the throttle could no be less than the value of Min % which is a bait annoying and I'm sure not the right setup.

Point to note we are not using an Airspeed Sensor.