Engine failure in small aircraft bi-plane creates the need for an off airport landing.

Attributes
ACN	187490
Time
Date	199108
Day	Wed
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : rld
State Reference	WA
Altitude	msl bound lower : 1700 msl bound upper : 1700
Environment
Flight Conditions	VMC
Light	Dusk
Aircraft 1
Controlling Facilities	tower : hou
Operator	general aviation : personal
Make Model Name	Small Aircraft
Flight Phase	cruise other
Route In Use	approach : visual enroute : direct
Flight Plan	None
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private
Experience	flight time last 90 days : 10 flight time total : 500 flight time type : 10
ASRS Report	187490
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : declared emergency other
Consequence	Other Other
Supplementary
Primary Problem	Aircraft

Narrative:

Return flight from prosser, wa, to richland, wa, at 1700 ft MSL. About 10 mins into flight engine RPM dropped to approximately 2000 RPM. Cruise RPM was 2450. Engine pitch changed and engine started to run rough. Performed magnetic checks, carburetor heat, mixture, etc checks, nothing worked. At this point it became obvious that I couldn't make airport because I couldn't maintain altitude at 90 mph (normal landing approach speed) and engine conditions were deteriorating. Below was a semi- deserted mobile home park. The 2 northern-most east/west streets were totally unoccupied. I proceeded to make a 360 degree approach to the most northern street and performed a routine landing. Aircraft was undamaged. Subsequent engine examination revealed that #3 piston was gone. Also, the exhaust valve was gone. Probable sequence, supported by visible evidence, indicates that the exhaust valve separated at the valve end and proceeded to destroy the #3 piston and other parts of the engine. There is very little salvageable from this engine. Plane is an experimental and the engine is a converted xyz with approximately 150 hours since overhaul by an FAA certified shop.

Original NASA ASRS Text

Title: ENG FAILURE IN SMA BI-PLANE CREATES THE NEED FOR AN OFF ARPT LNDG.

Narrative: RETURN FLT FROM PROSSER, WA, TO RICHLAND, WA, AT 1700 FT MSL. ABOUT 10 MINS INTO FLT ENG RPM DROPPED TO APPROX 2000 RPM. CRUISE RPM WAS 2450. ENG PITCH CHANGED AND ENG STARTED TO RUN ROUGH. PERFORMED MAG CHKS, CARB HEAT, MIXTURE, ETC CHKS, NOTHING WORKED. AT THIS POINT IT BECAME OBVIOUS THAT I COULDN'T MAKE ARPT BECAUSE I COULDN'T MAINTAIN ALT AT 90 MPH (NORMAL LNDG APCH SPD) AND ENG CONDITIONS WERE DETERIORATING. BELOW WAS A SEMI- DESERTED MOBILE HOME PARK. THE 2 NORTHERN-MOST E/W STREETS WERE TOTALLY UNOCCUPIED. I PROCEEDED TO MAKE A 360 DEG APCH TO THE MOST NORTHERN STREET AND PERFORMED A ROUTINE LNDG. ACFT WAS UNDAMAGED. SUBSEQUENT ENG EXAMINATION REVEALED THAT #3 PISTON WAS GONE. ALSO, THE EXHAUST VALVE WAS GONE. PROBABLE SEQUENCE, SUPPORTED BY VISIBLE EVIDENCE, INDICATES THAT THE EXHAUST VALVE SEPARATED AT THE VALVE END AND PROCEEDED TO DESTROY THE #3 PISTON AND OTHER PARTS OF THE ENG. THERE IS VERY LITTLE SALVAGEABLE FROM THIS ENG. PLANE IS AN EXPERIMENTAL AND THE ENG IS A CONVERTED XYZ WITH APPROX 150 HRS SINCE OVERHAUL BY AN FAA CERTIFIED SHOP.

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.