 |
37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
Fuel gauge error resulting in aircraft departing with less than dispatch fuel boarded.
| Attributes | |
| ACN | 89503 |
| Time | |
| Date | 198806 |
| Day | Wed |
| Local Time Of Day | 0001 To 0600 |
| Place | |
| Locale Reference | airport : sea |
| State Reference | WA |
| Altitude | msl bound lower : 37000 msl bound upper : 37000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Dawn |
| Aircraft 1 | |
| Controlling Facilities | artcc : zse |
| Operator | common carrier : air carrier |
| Make Model Name | Medium Large Transport, Low Wing, 2 Turbojet Eng |
| Navigation In Use | Other Other |
| Flight Phase | cruise other |
| Route In Use | enroute airway : zse |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 203 flight time total : 13000 |
| ASRS Report | 89503 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 185 flight time total : 5100 |
| ASRS Report | 89502 |
| Events | |
| Anomaly | aircraft equipment problem : less severe |
| Independent Detector | other flight crewa |
| Resolutory Action | other |
| Consequence | Other |
| Supplementary | |
| Primary Problem | Aircraft |
| Air Traffic Incident | other |
Narrative:
First officer totaled the gauges at 24300#. According to the fuel slip, the fueler added 2481 gals to the 7200# showing on board giving him a total of 24200#. Shortly before departure, first officer noticed the #1 fuel gauge flashing alternately between error codes 2, 3, 4 and 6 and 10200#. He called a mechanic. However, when the mechanic and I arrived, the gauge was again showing 10200#. As the gauges appeared normal at this time, and I was confident that we had the correct amount of fuel on board, I decided to depart. If the problem reoccurred en route, I would write up the problem in hou. After takeoff we noticed that #1 gauge was showing about 8000 pounds or 2000# less than #2 gauge. We were burning out of the #3 tank at that time. I also noted that first officer, who was flying, was having to add left rudder trim to keep that aircraft flying straight. This indicated that the right wing was heavier than the left wing. To test my assumption, I stopped burning out of #3 tank and burned the right wing tank (#2) until its gauge showed equal to #1 gauge. Next I added the fuel showing on the gauges to the fuel showing on the fuel used counters. This gave me a figure of 21500# rather than the 24200# showing on the fuel slip. When I made radio contact with den, I asked maintenance for any suggestions. They said that west/O diverting to den, they could not help. From my calculations, I estimated that we would land in iah with 2500-3000# of fuel. As reserves are 4000# and as I felt that I could no longer trust my fuel gauges, I requested dispatch to divert to dfw. We arrived in dfw with 4500# showing on the gauges. When maintenance used the dip stick method, they found 5100 pounds on board. They then transferred all the remaining fuel to the center tank and added 750 gals to each wing tank. The #1 gauge showed 5000 pounds and the #2 gauge 4850#. We then departed to iah with no further incident.
Original NASA ASRS Text
Title: FUEL GAUGE ERROR RESULTING IN ACFT DEPARTING WITH LESS THAN DISPATCH FUEL BOARDED.
Narrative: F/O TOTALED THE GAUGES AT 24300#. ACCORDING TO THE FUEL SLIP, THE FUELER ADDED 2481 GALS TO THE 7200# SHOWING ON BOARD GIVING HIM A TOTAL OF 24200#. SHORTLY BEFORE DEP, F/O NOTICED THE #1 FUEL GAUGE FLASHING ALTERNATELY BTWN ERROR CODES 2, 3, 4 AND 6 AND 10200#. HE CALLED A MECH. HOWEVER, WHEN THE MECH AND I ARRIVED, THE GAUGE WAS AGAIN SHOWING 10200#. AS THE GAUGES APPEARED NORMAL AT THIS TIME, AND I WAS CONFIDENT THAT WE HAD THE CORRECT AMOUNT OF FUEL ON BOARD, I DECIDED TO DEPART. IF THE PROB REOCCURRED ENRTE, I WOULD WRITE UP THE PROB IN HOU. AFTER TKOF WE NOTICED THAT #1 GAUGE WAS SHOWING ABOUT 8000 LBS OR 2000# LESS THAN #2 GAUGE. WE WERE BURNING OUT OF THE #3 TANK AT THAT TIME. I ALSO NOTED THAT F/O, WHO WAS FLYING, WAS HAVING TO ADD LEFT RUDDER TRIM TO KEEP THAT ACFT FLYING STRAIGHT. THIS INDICATED THAT THE RIGHT WING WAS HEAVIER THAN THE LEFT WING. TO TEST MY ASSUMPTION, I STOPPED BURNING OUT OF #3 TANK AND BURNED THE RIGHT WING TANK (#2) UNTIL ITS GAUGE SHOWED EQUAL TO #1 GAUGE. NEXT I ADDED THE FUEL SHOWING ON THE GAUGES TO THE FUEL SHOWING ON THE FUEL USED COUNTERS. THIS GAVE ME A FIGURE OF 21500# RATHER THAN THE 24200# SHOWING ON THE FUEL SLIP. WHEN I MADE RADIO CONTACT WITH DEN, I ASKED MAINT FOR ANY SUGGESTIONS. THEY SAID THAT W/O DIVERTING TO DEN, THEY COULD NOT HELP. FROM MY CALCULATIONS, I ESTIMATED THAT WE WOULD LAND IN IAH WITH 2500-3000# OF FUEL. AS RESERVES ARE 4000# AND AS I FELT THAT I COULD NO LONGER TRUST MY FUEL GAUGES, I REQUESTED DISPATCH TO DIVERT TO DFW. WE ARRIVED IN DFW WITH 4500# SHOWING ON THE GAUGES. WHEN MAINT USED THE DIP STICK METHOD, THEY FOUND 5100 LBS ON BOARD. THEY THEN TRANSFERRED ALL THE REMAINING FUEL TO THE CENTER TANK AND ADDED 750 GALS TO EACH WING TANK. THE #1 GAUGE SHOWED 5000 LBS AND THE #2 GAUGE 4850#. WE THEN DEPARTED TO IAH WITH NO FURTHER INCIDENT.
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.