B777 Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 140; Flight Crew Total 22000; Flight Crew Type 2000
Communication Breakdown; Distraction; Human-Machine Interface
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy
Manuals; Human Factors; Company Policy; Aircraft
In a recent AOM revision the requirement to check the pilots' oxygen mask oxygen flow and mask microphone was removed from our normal operating procedures. I feel so strongly that a check of this critical piece of safe equipment is essential prior to every flight. Numerous fellow crew members and I have continued to do the check even though it's no longer SOP. On a recent international flight I discovered that my oxygen mask microphone was inoperative. I have no idea how many flights this aircraft had flown with this item being inoperative but it likely was many. Had an event occurred that required the oxygen masks to be donned the Captain would have had no way to establish crew communications; nor could he communicate with ATC as is required in several of our Emergency checklists. This would make a potentially difficult situation much more difficult and challenging; if not outright unsafe.
A B-777 Captain addressed his disagreement with his airline's decision to no longer require flight crews to test the functionality of the crew oxygen mask flow and microphone.  In support of his concern he detailed his discovery of an inoperative Oxygen mask microphone prior to an international flight.