Narrative:

While performing an overnight maintenance check on a 737-300 aircraft, I found the crew oxygen required servicing. I properly svced the oxygen bottle with oxygen and leak checked the system. After completing the check about XA30, I made the required logbook entry for servicing crew oxygen. I mistakenly wrote 'svced crew O2 with nitrogen,' which in fact I had not! My only explanation is I had a head cold for the past 3 days and was feeling tired. At crew change that same day, the crew discovered the logbook entry and the crew oxygen bottle was changed.

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Original NASA ASRS Text

Title: A B737-300 WAS DISPATCHED IN NON COMPLIANCE WITH AN IMPROPER LOGBOOK OXYGEN SVC SIGNOFF. ENTRY READ SVCED OXYGEN SYS WITH NITROGEN.

Narrative: WHILE PERFORMING AN OVERNIGHT MAINT CHK ON A 737-300 ACFT, I FOUND THE CREW OXYGEN REQUIRED SVCING. I PROPERLY SVCED THE OXYGEN BOTTLE WITH OXYGEN AND LEAK CHKED THE SYS. AFTER COMPLETING THE CHK ABOUT XA30, I MADE THE REQUIRED LOGBOOK ENTRY FOR SVCING CREW OXYGEN. I MISTAKENLY WROTE 'SVCED CREW O2 WITH NITROGEN,' WHICH IN FACT I HAD NOT! MY ONLY EXPLANATION IS I HAD A HEAD COLD FOR THE PAST 3 DAYS AND WAS FEELING TIRED. AT CREW CHANGE THAT SAME DAY, THE CREW DISCOVERED THE LOGBOOK ENTRY AND THE CREW OXYGEN BOTTLE WAS CHANGED.

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.