Backgrounder: Flight recorders
The International Civil Aviation Organization (ICAO) requires large commercial aircraft to carry 2 flight recorders: a flight data recorder (FDR) and a cockpit voice recorder (CVR). The FDR records parametric data for at least the last 25 hours of operation. The CVR records the flight crew’s communications and the aural environment of the cockpit for the last 2 hours of operation. Some newer flight recorders combine the functions of the FDR and CVR into a single unit. These units are referred to as cockpit voice and data recorders (CVDR) or combination recorders.
