Narrative:

During preflight I found that my oxygen mask leaked. About 10 mins prior to departure a mechanic came into the cockpit to try and fix the mask. The mechanic swapped my oxygen mask with the first observer's mask. Which was not being used on this flight. It was now about 5 mins prior to departure. The mechanic asked if we would write this maintenance item up in the air due to time constraints. I asked him to write it up and defer the first observer's mask. He said he wouldn't be able to defer it in time because he needed to get a 'control number' from headquarters and that would take 'a while.' I told him to defer it and call us in the air with the control number or give us the control number at the next station per our MEL. He said okay, he'll do that. I saw him writing in the logbook and I assumed he deferred the first observer's position. I never looked at the logbook after the mechanic was finished because we would have been late. When airborne I found that the mechanic had only written the discrepancy and written the fix. He did not sign it off or officially defer it. We had complied with the MEL requirement of not using the first observer's seat. However, we flew one leg with an 'open' write-up. Cause: being rushed.

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Original NASA ASRS Text

Title: FLC OF AN LGT OPERATED THE ACFT WHEN AN OXYGEN MASK DISCREPANCY FIX AND A DEFERRAL HAD NOT BEEN SIGNED OFF BY MAINT.

Narrative: DURING PREFLT I FOUND THAT MY OXYGEN MASK LEAKED. ABOUT 10 MINS PRIOR TO DEP A MECH CAME INTO THE COCKPIT TO TRY AND FIX THE MASK. THE MECH SWAPPED MY OXYGEN MASK WITH THE FIRST OBSERVER'S MASK. WHICH WAS NOT BEING USED ON THIS FLT. IT WAS NOW ABOUT 5 MINS PRIOR TO DEP. THE MECH ASKED IF WE WOULD WRITE THIS MAINT ITEM UP IN THE AIR DUE TO TIME CONSTRAINTS. I ASKED HIM TO WRITE IT UP AND DEFER THE FIRST OBSERVER'S MASK. HE SAID HE WOULDN'T BE ABLE TO DEFER IT IN TIME BECAUSE HE NEEDED TO GET A 'CTL NUMBER' FROM HEADQUARTERS AND THAT WOULD TAKE 'A WHILE.' I TOLD HIM TO DEFER IT AND CALL US IN THE AIR WITH THE CTL NUMBER OR GIVE US THE CTL NUMBER AT THE NEXT STATION PER OUR MEL. HE SAID OKAY, HE'LL DO THAT. I SAW HIM WRITING IN THE LOGBOOK AND I ASSUMED HE DEFERRED THE FIRST OBSERVER'S POS. I NEVER LOOKED AT THE LOGBOOK AFTER THE MECH WAS FINISHED BECAUSE WE WOULD HAVE BEEN LATE. WHEN AIRBORNE I FOUND THAT THE MECH HAD ONLY WRITTEN THE DISCREPANCY AND WRITTEN THE FIX. HE DID NOT SIGN IT OFF OR OFFICIALLY DEFER IT. WE HAD COMPLIED WITH THE MEL REQUIREMENT OF NOT USING THE FIRST OBSERVER'S SEAT. HOWEVER, WE FLEW ONE LEG WITH AN 'OPEN' WRITE-UP. CAUSE: BEING RUSHED.

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.