ABSTRACT
The flight interphone system provides facilities for interphone communication among flight compartment crew members and provides the means for them to receive, key and transmit using the various aircraft radio systems. The flight interphone system also extends communication to ground personnel at the nose gear interphone station and allows flight compartment crew members to communicate and to make passenger address announcements. The flight interphone system also incorporates amplifiers and mixing circuits in the audio accessory unit, audio selector panels, cockpit speakers, microphone/headphone jacks and press- to-talk (PTT) switches. In addition to the audio systems used for normal operation of the aircraft, large commercial aircraft are also required to carry a cockpit voice recorder (CVR). This device captures and stores information derived from a number of the aircraft's audio channels. In order to improve visibility and aid recovery, the external housing of the CVR is painted bright orange.
