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NTSB Report
August 4, 1989 · Piper PA-23-180 · N4376P
Lancaster, CA
Overview
Report Status
Probable Cause
Event Type
Accident
Date
August 4, 1989
Injury Outcomes
1 injury (1 minor injury)
Location
Lancaster, CA
Aircraft
Piper PA-23-180
Tail Number
N4376P
Operator
Simanski Donald E
Injuries
Minor
Aircraft Damage
Substantial
NTSB Number
LAX89LA263
AFTER COMPLETION OF AN ANNUAL INSPECTION, THE AIRCRAFT OWNER ELECTED TO CONDUCT A MAINTENANCE TEST FLIGHT. WHILE AIRBORNE, HE SHUT DOWN THE RIGHT ENGINE, THEN FEATHERED AND UNFEATHERED THE PROPELLER, AND RESTARTED THE ENGINE BY LETTING THE PROPELLER WINDMILL. WHEN HE FOLLOWED THE SAME PROCEDURE WITH THE LEFT ENGINE AND PROPELLER, THE PROPELLER FAILED TO UNFEATHER AND HE COULD NOT RESTART THE ENGINE. THE PILOT RETURNED TO THE AIRPORT WITH ONE ENGINE OPERATING AND ATTEMPTED TO EXTEND THE LANDING GEAR DURING PATTERN ENTRY. THE LANDING GEAR DID NOT EXTEND AND THE PILOT INITIATED A GO-AROUND. THE AIRCRAFT DID NOT CLIMB AND BEGAN TO LOOSE ALTITUDE. EVENTUALLY, IT COLLIDED WITH THE GROUND OFF AIRPORT DURING AN UNARRESTED DESCENT. THE LANDING GEAR EXTENSION AND RETRACTION SYSTEM WAS HYDRAULIC AND POWERED BY A PUMP ON THE LEFT ENGINE. THE FLIGHT MANUAL PROVIDED TWO ALTERNATE MEANS OF EMERGENCY GEAR EXTENSION, NEITHER OF WHICH THE PILOT ATTEMPTED ON THE FIRST LANDING APPROACH.
NTSB Probable Cause
THE PILOT'S FAILURE TO FOLLOW ESTABLISHED PROCEDURES IN RESTARTING THE ENGINE THAT DRIVES THE HYDRUALIC PUMP AND HIS FAILURE TO FOLLOW PUBLISHED EMERGENCY LANDING GEAR EXTENSION PROCEDURES. THE PILOT'S DECISION TO SHUT DOWN AN ENGINE AND FEATHER THE PROPELLER BEFORE ASSURING HIMSELF THAT THE PROPELLER WOULD UNFEATHER AND HIS INADEQUATE TRAINING IN EMERGENCY PROCEDURES WERE FACTORS IN THE ACCIDENT.
Full Narrative
AFTER COMPLETION OF AN ANNUAL INSPECTION, THE AIRCRAFT OWNER ELECTED TO CONDUCT A MAINTENANCE TEST FLIGHT. WHILE AIRBORNE, HE SHUT DOWN THE RIGHT ENGINE, THEN FEATHERED AND UNFEATHERED THE PROPELLER, AND RESTARTED THE ENGINE BY LETTING THE PROPELLER WINDMILL. WHEN HE FOLLOWED THE SAME PROCEDURE WITH THE LEFT ENGINE AND PROPELLER, THE PROPELLER FAILED TO UNFEATHER AND HE COULD NOT RESTART THE ENGINE. THE PILOT RETURNED TO THE AIRPORT WITH ONE ENGINE OPERATING AND ATTEMPTED TO EXTEND THE LANDING GEAR DURING PATTERN ENTRY. THE LANDING GEAR DID NOT EXTEND AND THE PILOT INITIATED A GO-AROUND. THE AIRCRAFT DID NOT CLIMB AND BEGAN TO LOOSE ALTITUDE. EVENTUALLY, IT COLLIDED WITH THE GROUND OFF AIRPORT DURING AN UNARRESTED DESCENT. THE LANDING GEAR EXTENSION AND RETRACTION SYSTEM WAS HYDRAULIC AND POWERED BY A PUMP ON THE LEFT ENGINE. THE FLIGHT MANUAL PROVIDED TWO ALTERNATE MEANS OF EMERGENCY GEAR EXTENSION, NEITHER OF WHICH THE PILOT ATTEMPTED ON THE FIRST LANDING APPROACH.
Flight
Event TypeAccident
Event Time12:40 PDT
Nearest AirportGen. William J. Fox (0nm N)
Runway24
Runway Length5001 ft
Runway Width150 ft
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftPiper PA-23-180
Tail NumberN4376P
Aircraft CategoryAir
DamageSubstantial
OperatorSimanski Donald E
Operating RulePart 91
Engines2
Engine TypeReciprocating
Engine DetailsLycoming · O-360-A1D · Reciprocating · 180
Seats5
People & Injuries
Injury Summary1 injury (1 minor injury)
Fatal0
Serious0
Minor1
Uninjured0
Total1
Crew 1Age 49 · First Class
Conditions
ConditionsVMC
LightDaylight
Wind240° @ 18 kt
Visibility59 sm
CeilingNone
Temperature / Dew Point0 C / 0 C
Altimeter29.00 inHg
Observation Time19:50
Weather SourceWFAC