Narrative:

On jun/xa/00 air carrier flight wxx arrived in ZZZ at XA35 from XXX. I was to check the engine oils and my co-worker was to perform a walkaround check. I svced #1 engine adding 2 quarts and closed the tank cap and oil service door. I then proceeded to #2 engine and also added 2 quarts. At the same time my co-worker opened the CSD servicing door to check the oil level. I saw that he left the CSD servicing door open and walked away, which to me meant that the CSD needed servicing and he was getting the service cart and overfill bottle. I feel I closed the oil tank cap and servicing door and then positioned the stand to service the CSD. We svced the CSD, closed the door. We then went to the cockpit. I entered the oil added in the logbook. The aircraft departed as flight yxy to WWW at XB55. According to the logbook entry by the flight crew after takeoff roll, #2 oil quantity dropped to 6.5 quarts. The aircraft did not return to ZZZ but deviated to YYY where according to the mechanic signoff in the logbook, found #2 engine oil cap off. Oil svced, engine ran, no leaks. I feel to help lessen the chance of this occurring, that if the oil tank caps were chained to the overfill lip of the tank, you could let the cap hang outside the servicing door and that way you would have to reinstall the cap so you could close the oil service door. Also, if it was chained you could not leave the cap on a work stand.

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Original NASA ASRS Text

Title: A DC9-30 WAS DISPATCHED IN NON COMPLIANCE WITH #2 ENG OIL TANK FILLER CAP MISSING RESULTING IN LOSS OF OIL.

Narrative: ON JUN/XA/00 ACR FLT WXX ARRIVED IN ZZZ AT XA35 FROM XXX. I WAS TO CHK THE ENG OILS AND MY CO-WORKER WAS TO PERFORM A WALKAROUND CHK. I SVCED #1 ENG ADDING 2 QUARTS AND CLOSED THE TANK CAP AND OIL SVC DOOR. I THEN PROCEEDED TO #2 ENG AND ALSO ADDED 2 QUARTS. AT THE SAME TIME MY CO-WORKER OPENED THE CSD SVCING DOOR TO CHK THE OIL LEVEL. I SAW THAT HE LEFT THE CSD SVCING DOOR OPEN AND WALKED AWAY, WHICH TO ME MEANT THAT THE CSD NEEDED SVCING AND HE WAS GETTING THE SVC CART AND OVERFILL BOTTLE. I FEEL I CLOSED THE OIL TANK CAP AND SVCING DOOR AND THEN POSITIONED THE STAND TO SVC THE CSD. WE SVCED THE CSD, CLOSED THE DOOR. WE THEN WENT TO THE COCKPIT. I ENTERED THE OIL ADDED IN THE LOGBOOK. THE ACFT DEPARTED AS FLT YXY TO WWW AT XB55. ACCORDING TO THE LOGBOOK ENTRY BY THE FLC AFTER TKOF ROLL, #2 OIL QUANTITY DROPPED TO 6.5 QUARTS. THE ACFT DID NOT RETURN TO ZZZ BUT DEVIATED TO YYY WHERE ACCORDING TO THE MECH SIGNOFF IN THE LOGBOOK, FOUND #2 ENG OIL CAP OFF. OIL SVCED, ENG RAN, NO LEAKS. I FEEL TO HELP LESSEN THE CHANCE OF THIS OCCURRING, THAT IF THE OIL TANK CAPS WERE CHAINED TO THE OVERFILL LIP OF THE TANK, YOU COULD LET THE CAP HANG OUTSIDE THE SVCING DOOR AND THAT WAY YOU WOULD HAVE TO REINSTALL THE CAP SO YOU COULD CLOSE THE OIL SVC DOOR. ALSO, IF IT WAS CHAINED YOU COULD NOT LEAVE THE CAP ON A WORK STAND.

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.