Narrative:

On preflight the F/east noted oil levels in #1 and #3 engine reaching minimum dispatch level and called for maintenance. After servicing #1 engine and while servicing #3 I was distracted by another crew member standing below my servicing buggy. After topping off #3 engine I climbed down to see what he needed. He wanted me to check something else on the aircraft and after doing so I returned to my servicing buggy, still thinking that I had finished #3 engine. I moved on to another aircraft. This aircraft took off and during the first part of the flight the crew noted the #3 engine oil level falling and then stabilizing at an acceptable level. Upon landing the crew called maintenance, who found the #3 engine oil service door missing along with the oil cap. I realize now that the biggest mistake I made was letting myself be distracted during a maintenance task. I have since changed my ways and will not allow (now even my lead) myself to be distracted during servicing or any other maintenance task. Ps: the ass-chewing I got from my foreman will also help me remember.

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Original NASA ASRS Text

Title: MECHANIC LEFT OIL CAP OFF LGT DURING RAMP SERVICE. CAP AND SERVICE DOOR MISSING ON ARR.

Narrative: ON PREFLT THE F/E NOTED OIL LEVELS IN #1 AND #3 ENG REACHING MINIMUM DISPATCH LEVEL AND CALLED FOR MAINT. AFTER SERVICING #1 ENG AND WHILE SERVICING #3 I WAS DISTRACTED BY ANOTHER CREW MEMBER STANDING BELOW MY SERVICING BUGGY. AFTER TOPPING OFF #3 ENG I CLBED DOWN TO SEE WHAT HE NEEDED. HE WANTED ME TO CHK SOMETHING ELSE ON THE ACFT AND AFTER DOING SO I RETURNED TO MY SERVICING BUGGY, STILL THINKING THAT I HAD FINISHED #3 ENG. I MOVED ON TO ANOTHER ACFT. THIS ACFT TOOK OFF AND DURING THE FIRST PART OF THE FLT THE CREW NOTED THE #3 ENG OIL LEVEL FALLING AND THEN STABILIZING AT AN ACCEPTABLE LEVEL. UPON LNDG THE CREW CALLED MAINT, WHO FOUND THE #3 ENG OIL SVC DOOR MISSING ALONG WITH THE OIL CAP. I REALIZE NOW THAT THE BIGGEST MISTAKE I MADE WAS LETTING MYSELF BE DISTRACTED DURING A MAINT TASK. I HAVE SINCE CHANGED MY WAYS AND WILL NOT ALLOW (NOW EVEN MY LEAD) MYSELF TO BE DISTRACTED DURING SERVICING OR ANY OTHER MAINT TASK. PS: THE ASS-CHEWING I GOT FROM MY FOREMAN WILL ALSO HELP ME REMEMBER.

Data retrieved from NASA's ASRS site as of August 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.