I have made a very hard decision tonight, I am giving up on the tricopter for the time being, the servo coming off the tilt mechanism is just plain bad design. Since I'm building the Y6 I can't see a reason to keep a Y6 and a tricopter, that was another build I wasnt planning on. Good news is that since I ordered 7 MT3515's for the Y6 and I have 3 good motors and one for testing that will give me plenty of spares.....
The Y6 should be far more reliable and be able to handle loosing one motor, it could even loose two but jut not on the same arm.
It was a bit of a worry watching my GoPro crash into the ground at high speed, I had just build up confidence it was good. I had just under 10 hours of crash free flying. I need to feel that I can sling my Sony A5100 onto one of my platforms, a Y6 gives me a higher level of comfort, but it will be some time before I feel I can put it on the frame.
Bad news is I killed one of the telemetry radio's, its taken the copper track off where the antenna connector connects to. Everything else appears good, all the motors are good now that I've cleared out the dirt (very time consuming as you dont want to spin the motor while stuff is still in there). The LiPo is less nicely packaged, I've check the cells, all good (same IR values too). So overall not too bad I have to say. I'm putting this down to the Quanum 15" props, they just vibrated too much which caused the tail servo to disconnect from the tilt mechanism, which then in a high spin as I killed the power it threw the tail motor a good 20m away. I ordered some more 12" and 13" CF props as they appear to be better balanced, I thought I had balanced the 15" before but I could hear they were vibrating (plus the FPV video was bouncing around).
Having reviewed the footage and telemetry logs, it seems if I have not killed the power it was looking like I might have been able to bring it to the ground in an uncontrolled spin. Just would have been down to the tail motor staying on long enough.....