Nothing is waterproof, especially considering the high stresses involved in an airplane accident. The flight data recorder is water resistant. It is also designed to minimize the probability of data loss even if it does get wet internally.
It was invented in 1956 by David Warren in Melbourne, Australia for commercial airliners. However, first was made in 1941 for use in flight test centers. In 1947 first market design was made.
The Flight Data Recorder collects and records data from up to 30 various parameters of the aircraft. This data can be used to investigate a crash and to study problems with the aircraft. The recorder...