Cessna 210 accident near Chino, California, August 26, 2020
On August 26, 2020 at about 3:20 pm local time, a 1960 Cessna 210, registered N9540T, was substantially damaged in an accident during landing near Chino, California (Chino airport). It was a personal 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 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.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 26, 2020 · about 3:20 pm local time
- Place
- Chino, California · Chino · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 210 Undesignat, built 1960 · all 210s on the register
- Registration
- N9540T · registry record · serial 57340
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
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.
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
What happened, in order
- Sys/Comp malf/fail (non-power) during landing defining event
- Landing gear collapse during landing
The NTSB's findings
- Aircraft › Aircraft systems › Hydraulic power system › Pump, main › Damaged/degraded
- Not determined › Not determined › (general) › (general) › Unknown/Not determined
- Aircraft › Aircraft systems › Landing gear system › Gear extension and retract sys › Inoperative
Pilot
- Certificate: private
- Ratings: single-engine land
- Last flight review: July 28, 2020
- Medical certificate: Class 3 (with waivers/limitations)
- Seat: sngl
- Injury: no injuries
The aircraft
- Airframe total time: 1,173.3 hours
- Last inspection: annual inspection, March 17, 2020
- Maximum gross weight: 2,899 lb
- Seats: 4
- Landing gear: retractable
- Engine: Continental IO-470 SERIES (piston); 0 hours total
The flight
- Departed from: CNO Chino CA
- Destination: CNO Chino CA
- Flight plan: none
- Runway 26R, 4,858 ft by 150 ft
Weather at the time
- Light: daylight
- Visibility: 9 statute miles
- Sky: clear
- Temperature: 77°F (25°C), dew point 61°F (16°C)
- Altimeter: 29.81 inHg
- Observation at 3:17 pm from KCNO
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
9 documents, released by the NTSB on July 8, 2022. View them here, or download them; the NTSB redacts some personal details before release, and this site shows the NTSB's own titles rather than its file names.
| # | Document | What it is | |
|---|---|---|---|
| 1 | Pilot/operator Aircraft Accident Report, NTSB Form 6120.1 | PDF, 10 pages | View Download |
| 2 | Record of E-mail Correspondence (Pilot) | PDF, 1 page | View Download |
| 3 | Record of Phone Conversation (Pilot) | PDF, 1 page | View Download |
| 4 | Records of E-mail Correspondence with Maintenance Facility | PDF, 3 pages | View Download |
| 5 | Record of E-mail Correspondence Anp Exam | PDF, 2 pages | View Download |
| 6 | Hydraulic Pump Exam | PDF, 1 page | View Download |
| 7 | Hydraulic Pump Evidence Control Form | PDF, 2 pages | View Download |
| 8 | Release of Aircraft Wreckage, NTSB Form 6120.15 | PDF, 1 page | View Download |
| 9 | Photo Array | PDF, 5 pages | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
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.