Both. See the acceleration plot upthread.
Yes.
Here is the gyro data for launch until apogee. I'm plotting the gyro data for both Blue Ravens. One has a solid line and the other has a dashed line.
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The roll rate (yellow line) was pretty moderate until the fins started fluttering at about 1.8 seconds, and then it railed at 2292 deg/sec. Below is zoomed into the first 2 seconds:
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The noisy part at the beginning is the rocket bouncing around inside the 12' tower. Tower exit was at 0.12 seconds. The velocity at that time was about 250 feet/second. There may be a hint of the fluttering to come at 0.6 seconds
Below I zoom in even further to show the first 0.4 seconds:
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The gyros in the 2 units have good agreement with each other when the dynamics are slow enough for the 500 Hz sample rate to capture. 500 Hz is pretty fast sampling, but it's not fast enough to do a good job of capturing all the motion of the rocket rattling inside the tower at 120 mph, as you can see from lots of triangular points in the first 0.12 seconds when the two gyros aren't capturing the same data. I'm pretty sure this is why the tilt estimates from the two altimeters disagree by about 6 degrees as soon as the rocket left the tower:
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With more normal flight profiles the sampling rate is fast enough to do a much better job of keeping track of the attitude.
The next two plots are the accel and gyro measurements zoomed in to look at the onset of fluttering:
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There is a hint of it starting at 0.586 seconds. At that point the rocket was going about 1900 feet/second. I think it could be that the fins were oscillating at that time and there could have been some damage starting to build up in the carbon fiber.
Here is a closeup of the column buckling failure mode of the outer plies of the fin stock:
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