WPR23LA321 · Cessna T210M
Cessna T210M · Accident: landing gear collapse
From an unrecorded airport to Modesto, CA
Event
- NTSB case
- WPR23LA321
- 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
- Event fatalities
- Unknown
- 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 T210M
- 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
- N6535B
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From not recordedTo Modesto, CA
- Aircraft age
- About 45 years (built 1978)
- 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 · flare/touchdown
- 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
- Landing gear collapse
- 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 was flying the airplane to an airport where the annual inspection was to be performed. During climb out, the airplane sustained a total loss of electrical power. The pilot elected to return to the departure airport, and during the return, she was able to regain communication on one radio. The pilot followed the emergency landing gear extension checklist and attempted to manually apply hydraulic pressure to extend the landing gear. However, she could not verify that the landing gear was fully extended and locked due to the electrical failure. She reported that she pumped the manual handle up and down over 55 times (cycles) and felt the handle was stiff when she stopped pumping. The pilot flew a visual approach to land and, while on the base leg, tower personnel told her the gear appeared to be down. The pilot continued the approach, and during landing, both main landing gear collapsed, resulting in the airplane exiting the runway and striking a fence and brush. The owner of the airplane did not respond to investigator inquiries, and disposed of the airplane before an examination could be completed. As a result, the reason for the electrical failure that precipitated the landing gear collapse could not be determined. The Landing Gear Failure to Extend checklist directs the pilot to pump the emergency hand pump “until resistance becomes heavy - about 65 cycles,” and contains a note that indicated, “It takes about 55 cycles (110 strokes) to extend the gear.” The accident is consistent with the landing gear not extending normally following a loss of electrical power, and subsequently was not locked in the down position following completion of the emergency gear extension checklist. Although the pilot pumped the emergency gear extension handle the minimum recommended times, the pressure created was likely insufficient to ensure the landing gear were fully extended and locked in the down position, which resulted in the main landing gear collapsing during landing.
Probable cause
Insufficient hydraulic pressure to the landing gear system following the completion of the emergency gear extension checklist, which resulted in the main landing gear collapsing during landing. Contributing to the accident was a loss of electrical power for reasons that could not be determined based on available evidence, which resulted in a failure of the normal landing gear extension system.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR23LA321
- Event ID
- 20230822192922
- Case number
- WPR23LA321
- 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: 9330bd76bd0dcd1d35dd10c6addcbdc38af4e3ff8dc91509d1e1f3388f7827d9; retrieved 2026-09-16T18:02:12.156Z.