Mooney M20J accident near Emigrant Gap, California, August 28, 1999
On August 28, 1999 at about 8:10 pm local time, a Mooney M20J, registered N4201S, was substantially damaged in an accident near Emigrant Gap, California (Blue Canyon Airport). It was a personal flight under general aviation rules (Part 91). 2 people had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The fatigue failure and separation of the number three cylinder due to the cylinder overhaul facility's improper inspection and quality control processes.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 28, 1999 · about 8:10 pm local time
- Place
- Emigrant Gap, California · Blue Canyon Airport · map
- Type
- Accident
- Injuries
- 2 people had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Mooney M20J · all M20Js on the register
- Registration
- N4201S · registry record · serial 24-0573
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot was at cruise altitude of 9,500 feet when he heard a loud metallic bang. The airframe began to shake violently and the engine started running rough immediately following the noise. The pilot turned toward a nearby airport and the engine suddenly quit. The pilot was able to glide to the airport and touched down on the 3,300-foot-long runway; however, he had carried extra speed on the approach to allow a maneuvering margin to miss a large ravine off the runway's approach end. The airplane ran off the end of the runway and subsequently struck scrub bush. Postaccident examination of the engine revealed that the number three cylinder had separated in half between the Nos. 9 and 10 cooling fins. Metallurgical examination disclosed that the fracture was due to a fatigue crack, which had emanated from a notch and groove on the outer radius of one cooling fin. The notch and groove were painted the same color as the engine. The engine was overhauled 16 hours prior to the accident with 3 new cylinders installed, including the failed one.
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: 466 hours in all; 264 in this make and model; 20 in the last 90 days; 16 in the last 30 days; 399 as pilot in command
- Medical certificate: Class 3 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 4,889 hours
- Last inspection: annual inspection, June 25, 1999; 20 hours since
- Maximum gross weight: 2,740 lb
- Seats: 4
- Landing gear: retractable
- Engine: Lycoming IO-360-A3B6D (piston); 0 hours total
The flight
- Departed from: KWGF Palmdale CA at 6:10 pm
- Destination: KTRK Truckee CA
- Flight plan: none
- Runway 15, 3,300 ft by 50 ft
Weather at the time
- Light: daylight
- Wind: from 240° at 6 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 73°F (23°C), dew point 43°F (6°C)
- Altimeter: 30.00 inHg
- Observation at 7:52 pm from BLU, 1 miles away
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.
Other NTSB records under N4201S the same tail number, which may have belonged to a different aircraft at the time
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.