I was down in the fitness center at the hotel this morning, watching the tv screen in the elliptical machine. (No, I'm not kidding. Exercise has come a long way towards becoming "fun.") The Today Show was discussing the latest with the USAirways Flight 1549 event, and they played this video: http://today.msnbc.msn.com/id/28688215/. (Sorry for the link - I couldn't get the embedding to work.)
In this story, they revealed that the "Jetliner’s data recorders on way to D.C." They show video of the Cockpit Voice Recorder (CVR) and the Flight Data Recorder (FDR) being carried in coolers full of water. I have to admit, this caught me by surprise. I didn't expect this. So I did a little research.
From the NTSB website, a little background:
Large commercial aircraft and some smaller commercial, corporate, and private aircraft are required by the FAA to be equipped with two "black boxes" that record information about a flight. Both recorders are installed to help reconstruct the events leading to an aircraft accident. One of these, the Cockpit Voice Recorder (CVR), records radio transmissions and sounds in the cockpit, such as the pilot's voices and engine noises. The other, the Flight Data Recorder (FDR), monitors parameters such as altitude, airspeed and heading. The older analog units use one-quarter inch magnetic tape as a storage medium and the newer ones use digital technology and memory chips. Both recorders are installed in the most crash survivable part of the aircraft, usually the tail section.
All of that you may already know. What you may not know (I sure didn't) is:
In the United States, when investigators locate a black box it is transported to the computer labs at the National Transportation Safety Board (NTSB). Special care is taken in transporting these devices in order to avoid any (further) damage to the recording medium. In cases of water accidents, recorders are placed in a cooler of water to keep them from drying out. (Emphasis mine) "What they are trying to do is preserve the state of the recorder until they have it in a location where it can all be properly handled," Doran said. "By keeping the recorder in a bucket of water, usually it's a cooler, what they are doing is just keeping it in the same environment from which it was retrieved until it gets to a place where it can be adequately disassembled." From HowStuffWorks.