MD-11
Maintenance Airframe; Maintenance Powerplant
Troubleshooting; Time Pressure; Situational Awareness; Communication Breakdown; Workload
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural MEL / CDL; Deviation / Discrepancy - Procedural Maintenance; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Weight And Balance; Ground Event / Encounter Fuel Issue
General Maintenance Action; General Flight Cancelled / Delayed
Aircraft; Equipment / Tooling; MEL; Procedure; Software and Automation
When the fuel stick calculator was first approved for MD11; I had an aircraft that was not on a level ramp (roll attitude) with a number 3 fuel quantity on deferral. I used the online fuel stick calculator to try and verify the fuel quantity in the #3 tank. The numbers were off significantly. I used the maintenance manual procedure to correctly measure the quantity and it matched the known quantity. Afterwards I did more research and found that the web based fuel stick calculator to be inaccurate with the RH wing tanks of all fleets if the ramp isn't level. The problem stems from the fact that there is only one selection for wing tanks and that selection includes both left and right tanks. The calculator gives the same quantity for left and right tanks regardless of the roll selected. I had sent emails to the website contact and the Director of Maintenance office. Periodically throughout the last 6 years I have been sending emails to the office and discussed with my managers trying to get this corrected. About 6 months ago there was a read and sign about the importance of doing accurately sticking the tanks. This prompted me notifying the Maintenance office about the problems with the calculator again. I checked today and it still hasn't been corrected. I haven't heard back and I'm out of ideas to get this resolved. I believe the FAA would be very concerned if they were aware. Correct the calculator by making each tank a separate entry with its own table of quantities instead of combining left and right wings.
Technician reported frustration with a web based fuel stick calculator that has proven to be inaccurate over a period of six years.