Probable cause
A fatigue failure of the left main landing gear hydraulic actuator, which resulted in a loss of hydraulic fluid that prevented the pilot from lowering the landing gear to the fully extended position and maintaining directional control after landing.
NTSB analysis
While on the downwind leg of the traffic pattern, the flight instructor was unable to fully extend the landing gear. The landing gear appeared to be stuck in a transitional position, which the flight instructor attempted to resolve by moving the gear selector back to the gear-up position; however, she observed no movement. After about 1.5 hours of troubleshooting the landing gear, the flight instructor decided to land with the gear partially extended. The airplane touched down with the nose gear locked and the pilot was unable to attain directional control. The airplane veered off the runway, coming to rest in the grass.
Examination of the hydraulic system revealed that the left main landing gear hydraulic actuator barrel was fractured adjacent to the end cap. A fracture at the retainer clip groove exhibited striations consistent with fatigue crack propagation, and other fractures through the barrel exhibited signatures of overstress failure. It is likely that, once the fatigue crack grew to a significant depth, the housing cracked further from overstress and hydraulic fluid leaked out of the system, preventing the landing gear from extending properly.
The airplane manufacturer had previously issued instructions for modification of some landing gear hydraulic actuators installed on the accident airplane make and model, and an FAA airworthiness directive (AD) was subsequently issued to mandate the modifications. The maintenance records showed that the AD was performed on the accident airplane.
This is at least the fourth known failure of this model of actuator that resulted in an accident. The location, size, and physical features of the cracks were consistent among the accidents.
Text from the NTSB. Open the NTSB docket for WPR23LA213 for the full record.
Event
- Date
- May 30, 2023
- Type
- Accident
- Place
- Tacoma, Washington
- Nearest airport
- Tacoma Narrows (TIW)
- Highest injury
- None
- Weather
- Visual (VMC)
- Light
- Day
Cessna 210
- N-number
- N9574X
- Category
- Airplane
- Year built
- 1962
- 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.