Flight diverted to mci when 3000 pounds of fuel was lost from the right wing tank.

Attributes
ACN	250794
Time
Date	199308
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : mkc airport : stl
State Reference	MO
Altitude	msl bound lower : 35000 msl bound upper : 35000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zkc
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other
Flight Phase	climbout : intermediate altitude cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain
Qualification	pilot : flight engineer pilot : atp pilot : cfi
Experience	flight time last 90 days : 90 flight time total : 8000 flight time type : 55
ASRS Report	250794
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer oversight : pic
Qualification	pilot : atp
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	other other : unspecified
Resolutory Action	other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

Flight departed stl to slc with student captain in left seat of medium large transport. Release fuel 38200 pounds (including 20000 pounds in center tank). Takeoff with all pumps on per company procedure. Approaching top of climb, flight attendant advised us that passenger in rear of aircraft on right side observed fuel streaming from outboard right wing. Captain (instructor pilot) went back to investigate, returned to cockpit and announced that we would land at mci due to fuel loss from right wing fuel vent. Declared emergency, landed mci. Passenger later reported fuel loss stopped shortly after captain returned to cockpit. After landing, flight was cancelled, aircraft inspected by company maintenance personnel. Flew same aircraft back to stl next morning on revenue flight. Logbook signoff indicated no problem found. Later learned that this problem is fairly well known to experienced medium large transport pilots, can be corrected by turning off center pumps, allowing mains to burn down, then turning ctrs back on. Company flight manual has procedure for uncommanded fuel transfer, but does not mention loss of fuel from fuel vent. Fuel remaining after landing mci was approximately 30000 pounds, indicating approximately 3000 pounds of fuel was lost overboard. Callback conversation with reporter revealed the following information: unable to call reporter but a call to another medium large transport pilot revealed that, usually, the most fuel lost from a siphoning tank is about 3000 pounds.

Original NASA ASRS Text

Title: FLT DIVERTED TO MCI WHEN 3000 LBS OF FUEL WAS LOST FROM THE R WING TANK.

Narrative: FLT DEPARTED STL TO SLC WITH STUDENT CAPT IN L SEAT OF MLG. RELEASE FUEL 38200 LBS (INCLUDING 20000 LBS IN CTR TANK). TKOF WITH ALL PUMPS ON PER COMPANY PROC. APCHING TOP OF CLB, FLT ATTENDANT ADVISED US THAT PAX IN REAR OF ACFT ON R SIDE OBSERVED FUEL STREAMING FROM OUTBOARD R WING. CAPT (INSTRUCTOR PLT) WENT BACK TO INVESTIGATE, RETURNED TO COCKPIT AND ANNOUNCED THAT WE WOULD LAND AT MCI DUE TO FUEL LOSS FROM R WING FUEL VENT. DECLARED EMER, LANDED MCI. PAX LATER RPTED FUEL LOSS STOPPED SHORTLY AFTER CAPT RETURNED TO COCKPIT. AFTER LNDG, FLT WAS CANCELLED, ACFT INSPECTED BY COMPANY MAINT PERSONNEL. FLEW SAME ACFT BACK TO STL NEXT MORNING ON REVENUE FLT. LOGBOOK SIGNOFF INDICATED NO PROB FOUND. LATER LEARNED THAT THIS PROB IS FAIRLY WELL KNOWN TO EXPERIENCED MLG PLTS, CAN BE CORRECTED BY TURNING OFF CTR PUMPS, ALLOWING MAINS TO BURN DOWN, THEN TURNING CTRS BACK ON. COMPANY FLT MANUAL HAS PROC FOR UNCOMMANDED FUEL TRANSFER, BUT DOES NOT MENTION LOSS OF FUEL FROM FUEL VENT. FUEL REMAINING AFTER LNDG MCI WAS APPROX 30000 LBS, INDICATING APPROX 3000 LBS OF FUEL WAS LOST OVERBOARD. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: UNABLE TO CALL RPTR BUT A CALL TO ANOTHER MLG PLT REVEALED THAT, USUALLY, THE MOST FUEL LOST FROM A SIPHONING TANK IS ABOUT 3000 LBS.

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.