Cessna C-172P accident near Hesperia, California, July 20, 1991
On July 20, 1991 at about 7:30 pm local time, a Cessna C-172P, registered N54694, was substantially damaged in an accident near Hesperia, California. It was a personal flight under general aviation rules (Part 91). No one was hurt; 2 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
A STUCK ENGINE THROTTLE DUE TO IMPROPER MAINTENANCE PROCEDURES.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 20, 1991 · about 7:30 pm local time
- Place
- Hesperia, California · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna C-172P
- Registration
- N54694 · registry record · serial 17275037
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE PILOT DECIDED TO DIVERT TO HESPERIA DUE TO WEATHER. DURING THE ENROUTE LET DOWN, THE PILOT DISCOVERED THAT THE THROTTLE CONTROL WAS FROZEN AND COULD NOT BE MOVED WHEN HE ATTEMPTED TO ADD POWER. THE THROTTLE WAS FROZEN AT AN ENGINE POWER LEVEL INSUFFICIENT TO MAINTAIN LEVEL FLIGHT AND THE AIRCRAFT COLLIDED WITH HIGH TENSION POWER LINES WHILE ATTEMPTING TO MANEUVER TO THE RUNWAY. THE AIRCRAFT WAS EXAMINED BY FAA AIRWORTHINESS INSPECTORS WHO CONFIRMED THAT THE THROTTLE WAS FROZEN IN AN INTERMEDIATE SETTING. THE ENGINE WAS OVERHAULED ON JUNE 18, 1991. AT THAT TIME THE CARBURETOR WAS ALSO OVERHAULED, INCLUDING THE INSTALLATION OF NEW THROTTLE BUSHINGS AND A SHAFT. BETWEEN THE ENGINE OVERHAUL AND THE DATE OF THE ACCIDENT, THE AIRCRAFT DISCREPANCY LOG SHEETS MAINTAINED BY SOUTHBAY AVIATION DOCUMENTED SIX PRIOR COMPLAINTS BY RENTER PILOTS THAT THE THROTTLE WAS STICKING ON AN INTERMITTENT BASIS. THE CORRECTIVE ACTION RECORDED ON THE DISCREPANCY SHEETS CONSISTED OF REPLACING THE THROTTLE CABLE.
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: private
- Ratings: single-engine land
- Flight time: 117 hours in all; 30 in this make and model; 8 in the last 90 days; 6 in the last 30 days; 62 as pilot in command
- Medical certificate: Class 3 (valid medical--no waivers/lim.)
- Seat: unk
The aircraft
- Last inspection: inspection type not recorded, January 2, 2000
- Maximum gross weight: 2,300 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming O-320-D2J (piston); 0 hours total
- Operator: South Bay Aviation
The flight
- Departed from: LAS Las Vegas NV at 5:00 pm
- Destination: TOA Torrance CA
- Flight plan: VFR
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 210° at 15 knots
- Visibility: 12 statute miles
- Sky: clear
- Temperature: 84°F (29°C), dew point 0°F (-18°C)
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 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.