Narrative:

On oct/sun/02 while working at company X, a third party contract maintenance company performing a turnaround service for company Y, I observed aircraft X (a B757) with an oil quantity of 10 quarts and 20 quarts left and right engines respectively. I accomplished visual walkaround and did not find any significant oil leakage. I then called company Y aircraft maintenance control in ZZZ1 for guidance. I was informed by maintenance controller that l-hand engine oil consumption was within limit of 2.4 quarts per hour based upon flight hours. Maintenance control facsimile'ed reference to company Y operations office where I then received it from the company Y passenger service representative. I then read the oil consumption limit of 2.4 quarts per hour. I was informed the flight time since last oil service was 4.5 hours. I svced l-hand engine to full (20 quarts on sight gauge) adding 9 quarts of oil, which I calculated to be 2.0 quarts per flight hour -- within limit as maintenance control had said. I documented oil add in logbook, called maintenance control back with oil add. I was told aircraft would be placed on 'oil watch.' at departure, I informed captain of l-hand engine oil add and that if he saw unusual oil consumption, he should make an item in the logbook. He agreed and flight departed. The next time I reported for work (I'm part time at company) was oct/tue/02. I was 'talking shop' with another mechanic when the subject of the above mentioned aircraft came up. I mentioned that while 2.4 quarts per hour seemed high, it was within limits, to which he responded that the limit is 2.4 pints per hour. I disagreed and got the reference I got from maintenance control from my clipboard, which I'd saved, where I read to my horror that the limit was 2.4 pints per hour -- not quarts! In retrospect, I think that maintenance control's assurance that the limit was 2.4 quarts may have put me in the 'quarts mode.' the oil was in quart cans and the sight gauge on the engine is in quarts, too. When I read the paperwork, I saw the 2.4 limit. The word 'pints' failed to register in my mind. It's my understanding aircraft operated in this condition until someone realized it was out of limit and problem was addressed.

Related reports:

Google
 

Original NASA ASRS Text

Title: A B757-200 WAS DISPATCHED IN NON COMPLIANCE WITH THE R ENG OIL CONSUMPTION BEYOND MAINT MANUAL LIMITS.

Narrative: ON OCT/SUN/02 WHILE WORKING AT COMPANY X, A THIRD PARTY CONTRACT MAINT COMPANY PERFORMING A TURNAROUND SVC FOR COMPANY Y, I OBSERVED ACFT X (A B757) WITH AN OIL QUANTITY OF 10 QUARTS AND 20 QUARTS L AND R ENGS RESPECTIVELY. I ACCOMPLISHED VISUAL WALKAROUND AND DID NOT FIND ANY SIGNIFICANT OIL LEAKAGE. I THEN CALLED COMPANY Y ACFT MAINT CTL IN ZZZ1 FOR GUIDANCE. I WAS INFORMED BY MAINT CTLR THAT L-HAND ENG OIL CONSUMPTION WAS WITHIN LIMIT OF 2.4 QUARTS PER HR BASED UPON FLT HRS. MAINT CTL FAX'ED REF TO COMPANY Y OPS OFFICE WHERE I THEN RECEIVED IT FROM THE COMPANY Y PAX SVC REPRESENTATIVE. I THEN READ THE OIL CONSUMPTION LIMIT OF 2.4 QUARTS PER HR. I WAS INFORMED THE FLT TIME SINCE LAST OIL SVC WAS 4.5 HRS. I SVCED L-HAND ENG TO FULL (20 QUARTS ON SIGHT GAUGE) ADDING 9 QUARTS OF OIL, WHICH I CALCULATED TO BE 2.0 QUARTS PER FLT HR -- WITHIN LIMIT AS MAINT CTL HAD SAID. I DOCUMENTED OIL ADD IN LOGBOOK, CALLED MAINT CTL BACK WITH OIL ADD. I WAS TOLD ACFT WOULD BE PLACED ON 'OIL WATCH.' AT DEP, I INFORMED CAPT OF L-HAND ENG OIL ADD AND THAT IF HE SAW UNUSUAL OIL CONSUMPTION, HE SHOULD MAKE AN ITEM IN THE LOGBOOK. HE AGREED AND FLT DEPARTED. THE NEXT TIME I RPTED FOR WORK (I'M PART TIME AT COMPANY) WAS OCT/TUE/02. I WAS 'TALKING SHOP' WITH ANOTHER MECH WHEN THE SUBJECT OF THE ABOVE MENTIONED ACFT CAME UP. I MENTIONED THAT WHILE 2.4 QUARTS PER HR SEEMED HIGH, IT WAS WITHIN LIMITS, TO WHICH HE RESPONDED THAT THE LIMIT IS 2.4 PINTS PER HR. I DISAGREED AND GOT THE REF I GOT FROM MAINT CTL FROM MY CLIPBOARD, WHICH I'D SAVED, WHERE I READ TO MY HORROR THAT THE LIMIT WAS 2.4 PINTS PER HR -- NOT QUARTS! IN RETROSPECT, I THINK THAT MAINT CTL'S ASSURANCE THAT THE LIMIT WAS 2.4 QUARTS MAY HAVE PUT ME IN THE 'QUARTS MODE.' THE OIL WAS IN QUART CANS AND THE SIGHT GAUGE ON THE ENG IS IN QUARTS, TOO. WHEN I READ THE PAPERWORK, I SAW THE 2.4 LIMIT. THE WORD 'PINTS' FAILED TO REGISTER IN MY MIND. IT'S MY UNDERSTANDING ACFT OPERATED IN THIS CONDITION UNTIL SOMEONE REALIZED IT WAS OUT OF LIMIT AND PROB WAS ADDRESSED.

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.