Damage to acc, gyro sensors after crash?

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I had a good crash, into tall grass/soft dirt, from 20m after a esc-motor sync issue (no fault of pixhawk). The pixhawk was mounted on blue zeal gel, inside a “cage” and protected on all sides from any impact. It did not break away from its mounting gel either. Unfortunately, the battery disconnected upon impact, so the acc x, y, z flashlogs may not be showing the full impact. I got home and hooked it up to mission planner; Everything works fine. I armed it without motors and recorded a walk around the room and set it on the carpet for a while to capture a perfectly steady state. The flashlogs look great from the post crash test. They show all the movement while walking and settle right down to nothing when it was set down on the carpet…

I am aware how sensitive the accelerometers are. I have heard no advice either way as to how usable these flight controllers are after a crash. I would think, being mounted on the zeal gel, that the truly damaging, high G shock would be kept from the pixhawk.

[b]Anyone have any insight or experiences.

Is there a way to test, or am I just being paranoid?
[/b]
My first post here, so please forgive if I missed some etiquette.
Rob

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Dear Rob, I have had more than one spirited arrival and other than when I can see damage I have not caused sensors to fail.

I think the plan might be to proceed with caution for a few flights!

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These are not mechanical gyros , they will not be damaged by any force that the pub and components can handle. You may be concerned about components coming partially loose, giving bad connection, or heavier components like capacitors coils, barometer or connectors being ripped off before.
But the sensor itself is not damaged by over_g within the force range where other parts survive.

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Pub is a typo, it should be PCB

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Great replies guys! thanks for the reassurance.

I am aware these are not mechanical sensors. I would never had thought they could be damaged if it wasn’t for a conversation I had with a US based manufacturer of AlexMos control boards in Seattle. He described how sensitive the IMU was and how many were arriving already damaged on the PCB (functioning, but very poorly). They had to turn to a domestic aerospace-component manufacturer to get them treated correctly, every single time. I have also read that dropping one of these IMU’s on a hard table surface can deliver close to a 10,000 G shock, which can damage them. I guess when attached to a large mass, ie the PCB/copter, that the shock diminishes greatly?

My pixhawk is now going on a larger camera ship, so I will definitely be proceeding with caution!

I would still be interested in anyone elses experiences, though.

Thanks again!