Both engines surging and losing power. Diverted land at nearest airport.

Attributes
ACN	196383
Time
Date	199112
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : 33n
State Reference	DE
Altitude	msl bound lower : 8000 msl bound upper : 8000
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : dov tower : ind
Operator	general aviation : personal
Make Model Name	Small Aircraft, Low Wing, 2 Eng, Retractable Gear
Flight Phase	descent : approach other
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : atp pilot : cfi
Experience	flight time last 90 days : 30 flight time total : 2500 flight time type : 5
ASRS Report	196383
Person 2
Affiliation	government : military
Function	controller : approach
Qualification	controller : radar
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	other flight crewa
Resolutory Action	flight crew : declared emergency none taken : insufficient time other
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

Engines on small aircraft began surging and losing power in cruise. Unable to maintain altitude. Cancelled IFR, declared emergency. Shortly after, landed close by 33N. No damage, no injuries to passenger (1) or crew. Investigating fuel transfer valves, since trouble began after switching from main tanks to auxiliary tanks 50 mins into flight. Found valves to be only partially open. Cables may have failed to open them due to... Age?...ice? (4 days of rain prior to occurrence). No water found at drains. Pilot actions: applied carburetor heat, checked mags on, cycled propellers, mixtures, moved fuel selector levers back and forth, turned electrical boost pumps on. Finally, lowered gear for emergency landing via hydraulic pump handle. Tanks carefully drained for water prior to flight.

Original NASA ASRS Text

Title: BOTH ENGS SURGING AND LOSING PWR. DIVERTED LAND AT NEAREST ARPT.

Narrative: ENGS ON SMA BEGAN SURGING AND LOSING PWR IN CRUISE. UNABLE TO MAINTAIN ALT. CANCELLED IFR, DECLARED EMER. SHORTLY AFTER, LANDED CLOSE BY 33N. NO DAMAGE, NO INJURIES TO PAX (1) OR CREW. INVESTIGATING FUEL TRANSFER VALVES, SINCE TROUBLE BEGAN AFTER SWITCHING FROM MAIN TANKS TO AUX TANKS 50 MINS INTO FLT. FOUND VALVES TO BE ONLY PARTIALLY OPEN. CABLES MAY HAVE FAILED TO OPEN THEM DUE TO... AGE?...ICE? (4 DAYS OF RAIN PRIOR TO OCCURRENCE). NO WATER FOUND AT DRAINS. PLT ACTIONS: APPLIED CARB HEAT, CHKED MAGS ON, CYCLED PROPS, MIXTURES, MOVED FUEL SELECTOR LEVERS BACK AND FORTH, TURNED ELECTRICAL BOOST PUMPS ON. FINALLY, LOWERED GEAR FOR EMER LNDG VIA HYDRAULIC PUMP HANDLE. TANKS CAREFULLY DRAINED FOR WATER PRIOR TO FLT.

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.