WPR20LA288 · Cessna 210 Undesignat
Cessna 210 Undesignat · Accident: system/component malfunction/failure (non-power) during landing
From Chino Airport (CNO) to Chino Airport (CNO)
Event
- NTSB case
- WPR20LA288
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- Unknown
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Cessna 210 Undesignat
- Aircraft type
- Cessna 210
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N9540T
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Chino Airport (CNO), Chino, CATo Chino Airport (CNO), Chino, CA
- Aircraft age
- About 60 years (built 1960)
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Landing
- Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- System/component malfunction/failure (non-power)
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Aircraft › Aircraft systems
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot reported that the accident flight was the first flight since the airplane had undergone recent landing gear maintenance. While in the airport traffic pattern, he extended the landing gear; however, he noticed that it would not lock into the down position. Despite multiple attempts to cycle the landing gear, which included using the emergency landing gear extension procedure, he was unable to obtain a positive down and locked indication. While landing, both main landing gear collapsed and the left wing and left horizontal stabilizer impacted the runway surface, which resulted in substantial damage to the left elevator and horizontal stabilizer. Postaccident examination of the airplane revealed that the engine-driven hydraulic pump was not operational. No mechanical damage was observed within the engine’s accessory case. No evidence of any preexisting mechanical malfunction was observed with the airframe or emergency gear extension system. Examination of the engine-driven hydraulic pump revealed a torn section of an oil seal that surrounded the pump drive shaft. The oil seal was hard, brittle, and torn, which resulted in an oil leak that prevented the pump from holding pressure, which likely prevented the landing gear from fully extending and locking into place during landing. The reason for the emergency gear extension system not functioning could not be determined.
Probable cause
The failure of the engine-driven hydraulic pump, which resulted in the main landing gear not fully extending and locking into place during landing. Contributing to the accident was the failure of the emergency gear extension system for reasons that could not be determined.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR20LA288
- Event ID
- 20200826X30401
- Case number
- WPR20LA288
- Dataset
- full-current
- Source SHA-256
- 5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status, cause areas. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: f7266c0506a8b6b4edeab03b7ce2a5078813b26b3efe07772591a0edfd6af5c3; retrieved 2026-09-16T12:56:10.234Z.