Narrative:

I was the flight engineer on air carrier flight from ZZZ to xyz. 15 mins prior to block out, the captain discovered a leak in his oxygen mask hose. A ZZZ mechanic came to the cockpit and tried switching the mask out with the first observer's mask. This mask also had a leak when tested. The second observer's mask was then tried and it was usable. We had 2 oxygen masks which were unusable at this point with 2 entries in the logbook. One for the captain's mask which the mechanic signed off, and another for the 2 broken observer masks. Per air carrier policy the mechanic instructed me to obtain the appropriate signoff information via airborne communications with the company's maintenance in abc. I attempted to do this, but the MEL stated that at least 1 observer's mask was required to be operation. Another area stated that the captain could waive some non safety of flight items if he desired. It appeared we may have gone flying without proper approval. My conversation with abc had to be terminated so I could prepare for landing and I stated we would call abc maintenance on the phone after landing. During the phone conversation which included my captain, myself, abc maintenance, and xyz maintenance, we concluded an honest mistake was made in a vague area of the MEL. I stated I did not want to appear to cover up the situation in paperwork appearance. My position was noted, but the final solution was for me to line out the second oxygen mask entry and write entry in error. The xyz mechanic then made another entry stating a leaking mask was found at the flight engineer's station. This solution to me did not seem to be the best method and I stated that if any questions were asked of me later I would describe the events as I stated in this letter.

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Original NASA ASRS Text

Title: A B727-100 WAS DISPATCHED WITH 2 LEAKING OBSERVERS' OXYGEN HOSES DEFERRED IN CONFLICT WITH THE MEL.

Narrative: I WAS THE FE ON ACR FLT FROM ZZZ TO XYZ. 15 MINS PRIOR TO BLOCK OUT, THE CAPT DISCOVERED A LEAK IN HIS OXYGEN MASK HOSE. A ZZZ MECH CAME TO THE COCKPIT AND TRIED SWITCHING THE MASK OUT WITH THE FIRST OBSERVER'S MASK. THIS MASK ALSO HAD A LEAK WHEN TESTED. THE SECOND OBSERVER'S MASK WAS THEN TRIED AND IT WAS USABLE. WE HAD 2 OXYGEN MASKS WHICH WERE UNUSABLE AT THIS POINT WITH 2 ENTRIES IN THE LOGBOOK. ONE FOR THE CAPT'S MASK WHICH THE MECH SIGNED OFF, AND ANOTHER FOR THE 2 BROKEN OBSERVER MASKS. PER ACR POLICY THE MECH INSTRUCTED ME TO OBTAIN THE APPROPRIATE SIGNOFF INFO VIA AIRBORNE COMS WITH THE COMPANY'S MAINT IN ABC. I ATTEMPTED TO DO THIS, BUT THE MEL STATED THAT AT LEAST 1 OBSERVER'S MASK WAS REQUIRED TO BE OP. ANOTHER AREA STATED THAT THE CAPT COULD WAIVE SOME NON SAFETY OF FLT ITEMS IF HE DESIRED. IT APPEARED WE MAY HAVE GONE FLYING WITHOUT PROPER APPROVAL. MY CONVERSATION WITH ABC HAD TO BE TERMINATED SO I COULD PREPARE FOR LNDG AND I STATED WE WOULD CALL ABC MAINT ON THE PHONE AFTER LNDG. DURING THE PHONE CONVERSATION WHICH INCLUDED MY CAPT, MYSELF, ABC MAINT, AND XYZ MAINT, WE CONCLUDED AN HONEST MISTAKE WAS MADE IN A VAGUE AREA OF THE MEL. I STATED I DID NOT WANT TO APPEAR TO COVER UP THE SIT IN PAPERWORK APPEARANCE. MY POS WAS NOTED, BUT THE FINAL SOLUTION WAS FOR ME TO LINE OUT THE SECOND OXYGEN MASK ENTRY AND WRITE ENTRY IN ERROR. THE XYZ MECH THEN MADE ANOTHER ENTRY STATING A LEAKING MASK WAS FOUND AT THE FE'S STATION. THIS SOLUTION TO ME DID NOT SEEM TO BE THE BEST METHOD AND I STATED THAT IF ANY QUESTIONS WERE ASKED OF ME LATER I WOULD DESCRIBE THE EVENTS AS I STATED IN THIS LETTER.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.