Originally Posted by
portmanteau
DType, put "are flight recorders waterproof" into google.
Regardless of water damage, the data is recoverable.
My evidence is anecdotal, but I have recovered "water resistant" equipment soaked in 50-100 ft salt water before.
When I was a radio technician I restored many Motorola radios (surface mount, close spacing between traces, pre-MIL-STD-810C) to service after being immersed in salt water for weeks before the divers got around to harvesting them. I had a 100% recovery rate by flushing them and soaking them in distilled water, followed by a flush/soak of about 10% isopropanol and an low-temp oven bake. (They usually became corroded and unreliable after a year or so).
In this case, a rinse and bake after a week or two if immersion will certainly allow for full data recovery in short time.