Small aircraft has engine failure when switching tanks. Emergency landing.

Attributes
ACN	143303
Time
Date	199004
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : 1r8
State Reference	AL
Altitude	msl bound lower : 1500 msl bound upper : 1500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : personal
Make Model Name	Small Aircraft, High Wing, 1 Eng, Fixed Gear
Flight Phase	cruise other
Flight Plan	None
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : commercial pilot : instrument
Experience	flight time last 90 days : 112 flight time total : 1130 flight time type : 1010
ASRS Report	143303
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	other flight crewa
Resolutory Action	flight crew : declared emergency other
Consequence	Other
Supplementary
Primary Problem	Aircraft

Narrative:

Incident report: during level cruise at 1500' AGL, upon switching to left tank, the engine quit. Restart procedures were ineffective. Landed in hay field, no damage. Restart successful, took off on road. Cause: 1 week prior to flight, engine driven fuel pump began leaking. Left tank selector on, left tank emptied overnight. Upon replacing pump, 10 gals per side were put on board. Engine run on right tank was successful after fuel lines were purged (this model has no 'both' selection). Flight to other airport on right tank 20 mins long. Upon takeoff and reaching 1500', pilot switched to left tank. Air in line between reservoir and selector flowed into fuel pump causing vapor lock. With insufficient altitude to purge the lines, the forced landing was made. Attempts to restart on both right and left tank were unsuccessful. Preventive measures: properly flush or bleed fuel system after fuel system has been drained to prevent air anywhere in system. Pilot should run engine on both tank systems on ground until stable engine conditions are attained on both tank selections.

Original NASA ASRS Text

Title: SMA HAS ENGINE FAILURE WHEN SWITCHING TANKS. EMERGENCY LNDG.

Narrative: INCIDENT RPT: DURING LEVEL CRUISE AT 1500' AGL, UPON SWITCHING TO LEFT TANK, THE ENG QUIT. RESTART PROCS WERE INEFFECTIVE. LANDED IN HAY FIELD, NO DAMAGE. RESTART SUCCESSFUL, TOOK OFF ON ROAD. CAUSE: 1 WK PRIOR TO FLT, ENG DRIVEN FUEL PUMP BEGAN LEAKING. LEFT TANK SELECTOR ON, LEFT TANK EMPTIED OVERNIGHT. UPON REPLACING PUMP, 10 GALS PER SIDE WERE PUT ON BOARD. ENG RUN ON RIGHT TANK WAS SUCCESSFUL AFTER FUEL LINES WERE PURGED (THIS MODEL HAS NO 'BOTH' SELECTION). FLT TO OTHER ARPT ON RIGHT TANK 20 MINS LONG. UPON TKOF AND REACHING 1500', PLT SWITCHED TO LEFT TANK. AIR IN LINE BTWN RESERVOIR AND SELECTOR FLOWED INTO FUEL PUMP CAUSING VAPOR LOCK. WITH INSUFFICIENT ALT TO PURGE THE LINES, THE FORCED LNDG WAS MADE. ATTEMPTS TO RESTART ON BOTH RIGHT AND LEFT TANK WERE UNSUCCESSFUL. PREVENTIVE MEASURES: PROPERLY FLUSH OR BLEED FUEL SYS AFTER FUEL SYS HAS BEEN DRAINED TO PREVENT AIR ANYWHERE IN SYS. PLT SHOULD RUN ENG ON BOTH TANK SYSTEMS ON GND UNTIL STABLE ENG CONDITIONS ARE ATTAINED ON BOTH TANK SELECTIONS.

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.