NTSB Identification: DEN82FTE17
14 CFR Part 91: General Aviation
Accident occurred Saturday, March 06, 1982 in BOULDER, CO
Probable Cause Approval Date: 03/06/1983
Aircraft: CESSNA 172, registration: N4899F
Injuries: 2 Serious.

NTSB investigators either traveled in support of this investigation or conducted a significant amount of investigative work without any travel, and used data obtained from various sources to prepare this aircraft accident report.

THE ENGINE LOST POWER WHILE THE AIRCRAFT WAS CRUISING AT 7500 FT MSL AT NIGHT. DURING A FORCED LANDING, THE AIRCRAFT TOUCHED DOWN ON STEEP, ROCKY SOIL. THE AIRCRAFT BOUNCED AND THEN NOSED OVER AFTER A SECOND TOUCHDOWN. DURING AN INTERVIEW ABOUT TWO HOURS AFTER THE ACCIDENT, THE PILOT REPORTED AN INDICATION OF ABOUT 1800 RPM WHEN THE ENGINE LOST POWER. DURING THAT INTERVIEW, HE INDICATED THAT HE MAY NOT HAVE USED CARBURETOR HEAT WHILE ATTEMPTING TO RESTART THE ENGINE. LATER IN A WRITTEN STATEMENT HE REPORTED THAT HE "PUSHED IN CARB HEAT" WHILE ATTEMPTING TO RESTART THE ENGINE. THE TEMPERATURE WAS 27 DEGREES FAHRENHEIT, BUT THE DEW POINT WAS NOT DETERMINED. WHEN THE FUEL SYSTEM WAS CHECKED, NO CONTAMINATION WAS FOUND. HOWEVER, DURING IMPACT, THE FIREWALL SUMP HAD RUPTURED AND THE CARBURETOR WAS BROKEN AWAY FROM THE ENGINE. AN ENGINE TEARDOWN REVEALED NO PREIMPACT MALFUNCTION OR FAILURE.

The National Transportation Safety Board determines the probable cause(s) of this accident to be:

MISCELLANEOUS..UNDETERMINED



Contributing Factors

LIGHT CONDITION..DARK NIGHT


Contributing Factors

TERRAIN CONDITION..UPHILL


Contributing Factors

TERRAIN CONDITION..ROUGH/UNEVEN

Index for Mar1982 | Index of months