Cessna 172M accident near San Diego, California, June 21, 1999
On June 21, 1999 at about 5:20 am local time, a Cessna 172M, registered N61560, was destroyed in an accident near San Diego, California (Miramar airport). It was a personal flight under general aviation rules (Part 91). 1 person was seriously injured. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The mechanic's improper installation of nonapproved automotive electrical system parts, and his failure to ensure that all electrical connections were secure during the reinstallation, which resulted in the failure of the electrical system. The pilot's becoming lost and disoriented during the subsequent attempt to find an airport on the dark night flight was a factor.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- June 21, 1999 · about 5:20 am local time
- Place
- San Diego, California · Miramar · map
- Type
- Accident
- Injuries
- 1 person was seriously injured.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 172M · all 172Ms on the register
- Registration
- N61560 · no longer on the register · serial 17264640
- Damage
- Destroyed
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
During a practice instrument approach on a dark night, the aircraft began losing electrical power. The airplane was over a low cloud layer and the pilot cancelled his IFR clearance, informed ATC that he was losing electrical power and that he would fly back to home base under visual flight rules. He then flew in a southerly direction, following roads until he decided that he had flown far enough to locate his home airport. He was unable to locate the airport, made a 180-degree turn in an attempt to locate another airport, and found that he was unsure of his position. He elected to land on a large well-lit parking lot and collided with concrete barriers during the landing roll. An automotive alternator was found installed on the airplane, with a nonapproved support bracket that allowed for pulley misalignment, slack belt tension, and excessive vibration. The voltage regulator, alternator, and associated wiring harnesses were removed for functional testing. The voltage regulator and the alternator as separate units passed functional tests. The power input connector on the regulator fit loosely and allowed an intermittent electrical connection. Failure of the connection would allow the alternator to cease operating. A month prior to the accident, in response to pilot reports of intermittent low system output, a mechanic removed the alternator for repair. The automotive shop that performed the work found the unit had an acceptable voltage output, but the amperage was low. A diode in the bridge rectifier was replaced and the mechanic reinstalled the alternator on the engine. The mechanic said the alternator had been on the airplane for several years and 'it never occurred to [him] to check the Type Certificate Data Sheet' to ensure the alternator was approved for airplanes.
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; instrument: airplane
- Flight time: 240 hours in all; 144 in this make and model; 2 in the last 90 days; 161 as pilot in command
- Medical certificate: Class 3 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 10,412 hours
- Last inspection: 100-hour inspection, May 19, 1999; 121 hours since
- Maximum gross weight: 2,300 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming O-320-E2D (piston); 0 hours total
- Operator: Plus One Flyers INC.
The flight
- Departed from: MYF at 4:05 am
- Flight plan: IFR
- Runway 0
Weather at the time
- Light: night, dark
- Wind: from 260° at 4 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 55°F (13°C), dew point 52°F (11°C)
- Altimeter: 29.00 inHg
- Observation at 5:56 am from NKX
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.