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NTSB Report

September 11, 1991 · Cessna 172P · N97564

Hesperia, CA

Overview

Report Status

Probable Cause

Event Type

Accident

Date

September 11, 1991

Injury Outcomes

3 injuries (3 serious injuries)

Location

Hesperia, CA

Aircraft

Cessna 172P

Tail Number

N97564

Operator

Mohave Aviation

Injuries

Serious

Aircraft Damage

Substantial

NTSB Number

LAX91LA389

DURING THE INITIAL CLIMB, THE PILOT EXPERIENCED A LOSS OF ENGINE POWER, AND WAS UNABLE TO CONTINUE TO CLIMB OR MAINTAIN ALTITUDE. THE PILOT STATED TO FAA INSPECTORS THAT HE CHANGED FUEL TANKS AND ADJUSTED THE MIXTURE TO NO AVAIL. HE LANDED STRAIGHT AHEAD INTO UNSUITABLE TERRAIN AND NOSED OVER. INVESTIGATION DETERMINED THAT NUMBER 2 CYLINDER EXHAUST VALVE HAD STUCK OPEN FROM CARBON BUILD UP. A MANUFACTURERS SERVICE BULLETIN REGARDING THIS POSSIBLE PROBLEM HAD NOT BEEN ACCOMPLISHED AT THE RECOMMENDED TIME, NOR WERE OTHER ITEMS OF IN SERVICE INSPECTION/INFORMATION REGARDING VALVE STICKING ADDRESSED ACCORDING TO THE RECORDS AVAILABLE.

NTSB Probable Cause

A STUCK EXHAUST VALVE DUE TO THE OPERATOR'S NON COMPLIANCE WITH A MANUFACTURERS RECOMMENDED SERVICE BULLETIN ON THE ENGINE. CONTRIBUTING TO THE ACCIDENT WAS THE LACK OF SUITABLE TERRAIN FOR A SAFE LANDING.

Full Narrative

DURING THE INITIAL CLIMB, THE PILOT EXPERIENCED A LOSS OF ENGINE POWER, AND WAS UNABLE TO CONTINUE TO CLIMB OR MAINTAIN ALTITUDE. THE PILOT STATED TO FAA INSPECTORS THAT HE CHANGED FUEL TANKS AND ADJUSTED THE MIXTURE TO NO AVAIL. HE LANDED STRAIGHT AHEAD INTO UNSUITABLE TERRAIN AND NOSED OVER. INVESTIGATION DETERMINED THAT NUMBER 2 CYLINDER EXHAUST VALVE HAD STUCK OPEN FROM CARBON BUILD UP. A MANUFACTURERS SERVICE BULLETIN REGARDING THIS POSSIBLE PROBLEM HAD NOT BEEN ACCOMPLISHED AT THE RECOMMENDED TIME, NOR WERE OTHER ITEMS OF IN SERVICE INSPECTION/INFORMATION REGARDING VALVE STICKING ADDRESSED ACCORDING TO THE RECORDS AVAILABLE.

Flight

Event TypeAccident

Event Time11:00 PDT

Nearest Airport0nm N

Runway0

Flight Plan FiledNone

Aircraft FireNo

Aircraft ExplosionNo

Aircraft

AircraftCessna 172P

Tail NumberN97564

Aircraft CategoryAir

DamageSubstantial

OperatorMohave Aviation

Operating RulePart 91

Engines1

Engine TypeReciprocating

Engine DetailsLycoming · O-320-D2J · Reciprocating · 160

Seats4

People & Injuries

Injury Summary3 injuries (3 serious injuries)

Fatal0

Serious3

Minor0

Uninjured0

Total3

Crew 1Age 48 · First Class

Conditions

ConditionsVMC

LightDaylight

Wind330° @ 3 kt

Visibility30 sm

CeilingNone

Temperature / Dew Point0 C / 0 C

Altimeter0

Observation Time17:55

Weather SourceWFAC

500 – Data service is offline

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September 11, 1991 · Cessna 172P · N97564

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NTSB Probable Cause

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