A300
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Situational Awareness
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural MEL / CDL; Deviation / Discrepancy - Procedural Published Material / Policy
General Maintenance Action
Aircraft; Company Policy; Human Factors; MEL
The purpose of this report is to identify a possible MEL discrepancy as it pertains to the A300-600F operated at [company]. When we received our flight paperwork; it included MEL 23-XX-XX-X-X-X for an inoperative interphone system. This MEL was used to defer the system (the flight deck to ground function) after another crew wrote up difficulty communicating with the mechanic during their engine starts. We planned to use hand signals for engine starts to comply with the operations procedures of the MEL.During preflight of my oxygen mask; I discovered that I was unable to hear through the flight deck interphone system (overhead speakers) when transmitting. A closer review of the MEL title indicated that the flight deck interphone system was assumed to be inoperative. The full MEL title is: 'CREWMEMBER INTERPHONE SYSTEM - CARGO CONFIGURATION - FLIGHT DECK TO GROUND FUNCTION: (FLIGHT DECK AND SERVICE INTERPHONE SYSTEMS INOPERATIVE).' So; per the MEL; the aircraft appeared to be legal for dispatch. However; I discussed with the Captain my safety concern that we would have no way to communicate while wearing oxygen masks during flight (reasons would include smoke/fire/rapid decompression) if the flight deck interphone system was inoperative or deferred. The Captain put the flight deck interphone system discrepancy in the logbook; assuming the same MEL would be used to defer it. Had that been the case; I would have been forced to refuse to fly the aircraft because of the potential inability to communicate during an emergency requiring oxygen masks. Fortunately; the mechanics were able to replace the radio interphone amplifier and clear the write up and deferral. [Company] A300 procedures require the use of the interphone system and the overhead speakers for crew communications while using the oxygen masks. I am questioning the applicability of any MEL that would defer the flight deck interphone system on the A300.
A300 flight crew reported a MEL discrepancy regarding an inoperative interphone system; resulting in maintenance action.