NTSB Identification: FTW92LA016.
The docket is stored on NTSB microfiche number 44785.
Accident occurred Thursday, October 31, 1991 in WEST MEMPHIS, AR
Probable Cause Approval Date: 05/05/1993
Aircraft: BALKEMA/BOVEN KESTREL HAWK, registration: N601AS
Injuries: 1 Serious.
DURING A DAYTIME EXTENDED DOWNWIND APPROACH AT 300 FEET AGL, THE PILOT ALLOWED THE AIRSPEED TO DROP BELOW 50 MPH. THE ENGINE RPM DECREASED BELOW 1500 RPM AND SUBSEQUENTLY THE ENGINE LOST ALL POWER. THE PILOT MADE A DESCENDING RIGHT TURN FOR THE FORCED LANDING INTO A FIELD. AT APPROXIMATELY 40 FEET AGL, THE PILOT FLARED THE AIRPLANE, BUT LOST CONTROL AND IMPACTED THE TERRAIN IN A VERTICAL DESCENT. NO MECHANICAL MALFUNCTION TO FLIGHT CONTROLS OR STRUCTURAL COMPONENTS WERE FOUND DURING THE INVESTIGATION. ACCORDING TO THE MANUFACTURER'S LIMITATIONS, IMPROPER FUEL WAS IN THE AIRPLANE. THE MANUFACTURER'S FLIGHT MANUAL DID NOT ADDRESS NORMAL OR EMERGENCY PROCEDURES FOR THE AIRPLANE WHEN FLOAT EQUIPPED. THE OPERATOR WHO WAS INVOLVED IN THE MAINTENANCE OF THE AIRPLANE, REPORTED A HISTORY OF FUEL VAPORIZATION IN THE FUEL LINES.
The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
THE PILOT ALLOWED THE AIRCRAFT TO ENTER AN INADVERTENT STALL DURING FLARE AT EXCESSIVE ALTITUDE WHILE EXECUTING THE FORCED LANDING. FACTORS WERE THE PILOT IN COMMAND AND UNAUTHORIZED PERSON PERFORMED CARBURETOR MAINTENANCE ADJUSTMENTS PRIOR TO FLIGHT, AND THE USE OF AN IMPROPER GRADE FUEL.