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A B737-500 was dispatched in non compliance with the center tank fuel quantity indicator deferred in conflict with the MEL tank change order status.
| Attributes | |
| ACN | 443452 |
| Time | |
| Date | 199907 |
| Day | Mon |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | airport : zzz.airport |
| State Reference | US |
| Altitude | agl single value : 0 |
| Environment | |
| Light | Daylight |
| Aircraft 1 | |
| Operator | common carrier : air carrier |
| Make Model Name | B737-500 |
| Operating Under FAR Part | Part 121 |
| Flight Phase | ground : maintenance ground : parked |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | maintenance : technician |
| Qualification | technician : powerplant technician : airframe |
| Experience | maintenance technician : 31 |
| ASRS Report | 443452 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | maintenance : lead technician |
| Qualification | technician : powerplant technician : airframe |
| Events | |
| Anomaly | aircraft equipment problem : critical maintenance problem : non compliance with mel non adherence : far non adherence : published procedure |
| Resolutory Action | none taken : detected after the fact |
| Consequence | other |
| Factors | |
| Maintenance | contributing factor : manuals performance deficiency : non compliance with legal requirements performance deficiency : logbook entry |
| Supplementary | |
| Problem Areas | Company Maintenance Human Performance Aircraft Chart Or Publication |
| Primary Problem | Maintenance Human Performance |
| Situations | |
| Publication | Minimum Equipment List |
Narrative:
The fueler reported having trouble xferring fuel from center fuel tank. After talking with fueler and troubleshooting, I concluded that the center tank fuel quantity indication was malfunctioning. With the assistance of lead amt, we deferred center tank fuel quantity per MEL. The MEL for deferring center tank fuel quantity is very confusing. Technician must research a total of 4 change order auths in the computer. If some have been accomplished, deferral is allowed. If some have not been accomplished, deferral is allowed. The lead amt researched the change order auths and we both agreed that the change order authority/authorized had been accomplished because of the letter 'a' next to the change order authority/authorized number. I was wrong. The letter 'a' in that computer display is just a category of change order authority/authorized and not an accomplished indicator. After aircraft departed, line maintenance noticed error and grounded aircraft at bdl. Solution: air carrier MEL should be precise in which change order authority/authorized display to use. Terminal amt's rarely use these change order authority/authorized displays. More training in this area and a less confusing MEL would prevent this from happening again.
Original NASA ASRS Text
Title: A B737-500 WAS DISPATCHED IN NON COMPLIANCE WITH THE CTR TANK FUEL QUANTITY INDICATOR DEFERRED IN CONFLICT WITH THE MEL TANK CHANGE ORDER STATUS.
Narrative: THE FUELER RPTED HAVING TROUBLE XFERRING FUEL FROM CTR FUEL TANK. AFTER TALKING WITH FUELER AND TROUBLESHOOTING, I CONCLUDED THAT THE CTR TANK FUEL QUANTITY INDICATION WAS MALFUNCTIONING. WITH THE ASSISTANCE OF LEAD AMT, WE DEFERRED CTR TANK FUEL QUANTITY PER MEL. THE MEL FOR DEFERRING CTR TANK FUEL QUANTITY IS VERY CONFUSING. TECHNICIAN MUST RESEARCH A TOTAL OF 4 CHANGE ORDER AUTHS IN THE COMPUTER. IF SOME HAVE BEEN ACCOMPLISHED, DEFERRAL IS ALLOWED. IF SOME HAVE NOT BEEN ACCOMPLISHED, DEFERRAL IS ALLOWED. THE LEAD AMT RESEARCHED THE CHANGE ORDER AUTHS AND WE BOTH AGREED THAT THE CHANGE ORDER AUTH HAD BEEN ACCOMPLISHED BECAUSE OF THE LETTER 'A' NEXT TO THE CHANGE ORDER AUTH NUMBER. I WAS WRONG. THE LETTER 'A' IN THAT COMPUTER DISPLAY IS JUST A CATEGORY OF CHANGE ORDER AUTH AND NOT AN ACCOMPLISHED INDICATOR. AFTER ACFT DEPARTED, LINE MAINT NOTICED ERROR AND GROUNDED ACFT AT BDL. SOLUTION: ACR MEL SHOULD BE PRECISE IN WHICH CHANGE ORDER AUTH DISPLAY TO USE. TERMINAL AMT'S RARELY USE THESE CHANGE ORDER AUTH DISPLAYS. MORE TRAINING IN THIS AREA AND A LESS CONFUSING MEL WOULD PREVENT THIS FROM HAPPENING AGAIN.
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.