Cockpit Voice Recorder (CVR)
Definition
An aircraft recording device that captures audio from the cockpit area microphone and crew headsets over the last 2 hours (minimum) of flight for older aircraft, and at least 25 hours for aircraft with a maximum certificated takeoff mass over 27,000 kg manufactured after January 1, 2021, providing context for crew decisions and alerts leading to an accident.
- Records
- Cockpit area mic and crew headset audio
- Older aircraft minimum
- 2 hours
- Newer heavy aircraft
- At least 25 hours (over 27,000 kg, post-Jan 2021)
- Purpose
- Context for crew decisions and alerts before an accident
Common questions
Why was the CVR recording duration extended for newer aircraft?+
Older 2-hour recorders often had their earliest, sometimes most relevant, audio overwritten by the time of a crash if the flight ran long before the accident occurred, so regulators mandated much longer retention on newer heavy aircraft to preserve the full flight's cockpit audio.
How does CVR data get used together with the flight data recorder?+
Investigators synchronise CVR audio with the flight data recorder's parametric data so that a crew comment, alarm, or radio call can be matched to the aircraft's exact altitude, speed, and control inputs at that moment, building a combined timeline of what the crew heard and did.
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