Flight Data Recorder (FDR)
Records pertinent technical information about a flight. An FDR will record information about the performance of various aircraft systems, as well as the aircraft's speed, altitude, heading and other flight parameters. Like a cockpit voice recorder (CVR), a flight data recorder is designed to withstand the forces of a crash so that its information may be used to reconstruct the circumstances leading up to the accident (in some case, a digital flight data recorder, or DFDR).