Blade failure on tri

[biggestRCEfan]

My tri is a FT Electrohub, with the FT spec motors (Emax 2213-935kv), ESCs (Emax ESCs – BL Heli 20 amp), tough tilt, servo (emax ES3154 equivalent), naze32 acro FC board. Turnigy ActionCam mounted on RCExplorer battery tray. Props 1045, 3s setup.

In this video I fly it FPV. Please listen to the sound and give me your opinion. Conditions were a bit gusty, hence some oscillations. What concerns me is the grinding noise which I suspect comes from the PID tuning. FOr LOS I’m pretty happy (for my experience level) with the control loops. But is evident from the video that there is some motor/prop balancing issues, which is probably confirmed by some of the noises.

Here is my issue: after this flight I flew a bit LOS. From hover I accelerated nose-down at full throttle. After a few meters, something gave. I could hear something snap. It keeled over nose first into thickish grass, which made me think something happened with the tail rotor (which does not make sense … When I picked it up, the right prop had one blade separated about 1/3 span.

I post below a few pics of the break face.

I believe it is the blade failure that caused the crash, but what bugs me is that the copter did not roll over due to asymmetric lift, nor did I see massive vibration in the few moments before impact. Did the Naze shut ir down upon sensing excessive vibration?

Keen on some feedback.

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[biggestRCEfan]

This is before the crash …

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[donnyb]

Judging from the video, seems like It was pretty smooth. Sure there was something randomly vibrating. I would hope you had the ability to record the crash, that’s what could really give you a idea of how and why the flight ended they way it did. Props break, sometimes from a crash sometimes just poor quality. To be completely honest I like to use plastic props. They lose a bit of efficiency when you Wind them up, they flex instead of snapping. Usually if you lose power or snap a prop it will flip. I’m getting the impression that it didn’t flip. It nose dived. That tells me you could have momentarily lost signal to the flight controller.

But it’s hard to tell. But for good measure I would go over everything before your next flight. Making sure motors are mounted tight wires are snug no wobbly components and put it in the air.

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