Piper PA-23-180 accident near Lancaster, California, August 4, 1989
On August 4, 1989 at about 7:40 pm local time, a Piper PA-23-180, registered N4376P, was substantially damaged in an accident near Lancaster, California (Gen. William J. Fox airport). It was a flight of an unrecorded kind under general aviation rules (Part 91). 1 person had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
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.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 4, 1989 · about 7:40 pm local time
- Place
- Lancaster, California · Gen. William J. Fox · map
- Type
- Accident
- Injuries
- 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Piper PA-23-180 · all PA-23-180s on the register
- Registration
- N4376P · no longer on the register · serial 23-1881
- Damage
- Substantial damage
- Flight
- Flight of an unrecorded kind · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
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.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
Pilot
- Certificate: commercial pilot
- Ratings: multi-engine land; single-engine land; rotorcraft: helicopter
- Flight time: 1,159 hours in all; 155 in this make and model
- Medical certificate: Class 1 (valid medical--w/ waivers/lim.)
- Seat: unk
The aircraft
- Last inspection: inspection type not recorded; 0 hours since
- Maximum gross weight: 3,800 lb
- Seats: 5
- Landing gear: retractable
- Engine: Lycoming O-360-A1D (piston); 0 hours total
The flight
- Departed from: WJF at 7:00 pm
- Flight plan: none
- Runway 24, 5,001 ft by 150 ft
Weather at the time
- Light: daylight
- Wind: from 240° at 18 knots
- Visibility: 59 statute miles
- Sky: clear
- Temperature: 0°F (-18°C), dew point 0°F (-18°C)
- Altimeter: 29.00 inHg
- Observation at 7:50 pm from WJF, 1 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.