If you consider that the drive was powered off with the read/write heads parked ,, all data successfully written before the breakup... the drive was cocooned inside lightweight metal boxes within boxes as the experiment was self contained.. The experiment box may have started at 14,000 mph but it would have slowed to whatever “terminal velocity” would be for that ,, maybe 200mph at impact... so depending on the orientation at impact you may have had a head crash at the “parked head” location or you may have had the heads skate across the disks without the air cushion you would have with a running drive... the main thing was the disk wasn’t rotating, any data lost would have been just a byte or two per track... more than likely the worst damage was to the disk controller card.. simply disassembling the drive and swapping the platters into another drive of the same model would probably recover nearly all the data.
That's good stuff to know.
FMCDH(BITS)