Probable cause
A partial loss of engine power due to the fatigue fracture of the No. 3 exhaust valve rocker arm stud.
NTSB analysis
According to the flight instructor, the purpose of the flight was for the student pilot to practice touch-and-go landings. During the second takeoff, as the airplane was about 100-150 ft above ground level, he detected a loss of engine power and assumed control of the airplane. He landed the airplane on the remaining runway but overran the departure end of the runway and struck the airport perimeter fence. Both wings sustained substantial damage.
Examination of the engine revealed that the No. 3 exhaust rocker arm stud was fractured. Metallurgical examination of the fracture surfaces on the rocker arm stud revealed that it had fractured due to fatigue. The fatigue fracture of the No. 3 exhaust valve rocker arm stud likely led to the partial loss of engine power.
Text from the NTSB. Open the NTSB docket for WPR21LA069 for the full record.
Event
- Date
- Dec 13, 2020
- Type
- Accident
- Place
- San Diego, California
- Nearest airport
- Montgomery-Gibbs Executive (MYF)
- Highest injury
- None
- Weather
- Visual (VMC)
- Light
- Day
Cessna 172
- N-number
- N5098E
- Category
- Airplane
- Year built
- 1978
- Damage
- Substantial
- Operating rule
- Part 91 (general aviation)
- Purpose of flight
- Instructional
From the NTSB aviation accident database: N-registered aircraft, events since 2008, data through Oct 28, 2026. The file is published monthly, so the latest weeks are incomplete and recent records can change. The official source is the NTSB aviation investigation search. CheckAero is independent and not affiliated with the NTSB.