OK, first better state that the issue I have exists on TWO planes. These are standard PNP Hee Wing Ranger T-1’s, Hee Wing FC, ELRS, DJI Vista.
Tests flown Line of Sight.
Arm and disarm is normal. Flies OK in multicopter mode. Hovers on the spot, correcting for gusts,etc. Transitions to plane mode OK. As plane is reaching go/no go location having flown 100 metres from transition in fast level slightly climbing flight the throttle seems to cut, motor noise ceases. With no time to do anything else, I revert the Tx switch to multicopter mode, which it goes into as demanded and I fly a return and ccts like that. Back downwind, align for transition run, transition and it again transitions OK, accelerates and then again appears to cut.
Rinse and repeat. Happening with TWO Ranger VTOL planes, every time.
I fly other quads and planes over this site without issues. The cut is in a place flown through all the time by all my other models, but is almost within a metre or so the same cut point with both these VTOL planes.
The only place I can fly is not large and is tall tree lined, but I have flown it for may years with all sorts of models.
This symptom has destroyed any confidence I might have had to go for it, stay transitioned, and find out what happens, as it feels like an imminent crash into trees awaits!
Why would this sudden drop in motor revs be occurring, How can I find what is causing it and stop it please? Ideas?