How many VHF (Voice Communication) system can be in MEL for A340 aircraft?
What are the guidelines to decide that and is it different for aircraft operating under FAR 121, 125 and 135?
There are three VHF systems on A340 aircraft, as described here:
Item: VHF Systems
Number Installed: 3
Number Required for Dispatch: -
Remarks or Exceptions: Any in excess of those required by FAR may be inoperative provided it is not powered by an Essential Bus and not required for emergency procedures.
A minimum equipment list is required in the United States by the Federal Aviation Administration:
- When operating any turbine-powered aircraft such as jets or turboprops.
- When operating under part 135 (Commuter and on-demand operations)
- When operating under part 125 (Non-airline large aircraft operations)
MEL for FAR 121 is discussed here.