This is a list of aircraft accidents and incidents for which flight data recorders (FDRs) and/or cockpit voice recorders (CVRs) were not recovered, were destroyed, or otherwise failed to provide complete and correct information.
FDRs and CVRs in commercial aircraft continuously record information and can provide key evidence in determining the causes of an aircraft loss. The greatest depth from which a flight recorder has been recovered is , for the CVR of South African Airways Flight 295. Most flight recorders are equipped with underwater locator beacons to assist searchers in recovering them from offshore crash sites; however, these beacons run off a battery and eventually stop transmitting. A flight recorder cannot always be recovered, and some recorders that are recovered are too damaged to provide any data. Some recorders have also failed to provide adequate information for other reasons, such as poor maintenance, disconnection from power, or having relevant information recorded over by later events.