Cessna 152 accident near Bethany, Oklahoma, October 26, 2001
On October 26, 2001, a Cessna 152, registered N67797, was substantially damaged in an accident near Bethany, Oklahoma. It was an instructional flight under general aviation rules (Part 91). No one was hurt; 1 person was on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
the mechanic's failure to properly lock the exhaust valve's clearance adjusting screw locknut, which resulted in a loose nut, disabling of the exhaust valve pushrod, and a partial loss of engine power while in cruise flight. A contributing factor was the night light conditions for the forced landing.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- October 26, 2001
- Place
- Bethany, Oklahoma · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 152 · all 152s on the register
- Registration
- N67797 · registry record · serial 15282026
- Damage
- Substantial damage
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The private pilot reported that during a night cross-country flight, the engine began to lose power. The pilot could not maintain altitude to reach the airport, and therefore, elected to land in a field. The pilot landed the airplane in a field where it impacted a barbed wire fence. An FAA airworthiness inspector examined the engine with the assistance of an aircraft mechanic. The FAA inspector reported that they removed the #2 cylinder's rocker arm cover and noted that "the exhaust valve adjuster 'lock nut' had loosened and come completely off." Review of a maintenance record entry dated May 21, 2000, revealed that the #2 cylinder had been removed, repaired, and reinstalled at an aircraft total time of 825.0 hours. On August 13, 2001, the airplane and engine underwent their most recent 100-hour inspection at an aircraft and engine total time of 1,077.0 hours. The aircraft total time at the time of the accident is unknown. According to the engine operator's manual, persons installing pushrods for a cylinder are instructed to recheck the tappet clearance after run-in and lock the valve clearance adjusting screw in place with the locknut.
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: 140 hours in all
- Last flight review: October 20, 2000
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 1,077 hours
- Last inspection: 100-hour inspection, August 13, 2001
- Maximum gross weight: 1,670 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming O-235-L2C (piston); 0 hours total
The flight
- Departed from: 98F Duncan OK at 11:30 pm
- Destination: PWA Bethany OK
- Flight plan: none
Weather at the time
- Light: night
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 54°F (12°C), dew point 19°F (-7°C)
- Altimeter: 30.36 inHg
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.
Other NTSB records under N67797 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.