Robinson Helicopter CO R66 accident near Torrance, California, February 23, 2016
On February 23, 2016 at about 7:45 pm local time, a 2009 Robinson Helicopter CO R66, registered N266RH, was substantially damaged in an accident during maneuvering near Torrance, California (Zamperini Field). It was a flight test 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
A vibration of the helicopter, which resulted in an autorotation to soft terrain and subsequent impact of the tail boom with the main rotor. The reason for the vibration could not be determined because postaccident examination revealed no malfunctions or anomalies that would have precluded normal operation.
Source: NTSB aviation accident database, copy made October 12, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- February 23, 2016 · about 7:45 pm local time · cases in 2016
- Place
- Torrance, California · Zamperini Field · cases near this airport · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Robinson Helicopter CO R66 NO SERIES, built 2009
- Registration
- N266RH · registry record · serial 0002
- Damage
- Substantial damage
- Flight
- Flight test · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The commercial pilot was performing company flight testing in the helicopter. After performing an air taxi and a hovering autorotation, the pilot conducted a simulated maximum performance takeoff. About 200 ft above ground level, the pilot heard a noise and felt a momentary helicopter vibration. He subsequently performed a precautionary autorotation to a grass area on airport property. The pilot stated that the helicopter had forward speed during the landing and that the grass was soft; as a result, the helicopter entered a fore-aft rocking motion after touchdown, and the main rotor contacted the tail boom, resulting in substantial damage. Postaccident review of data from the engine monitoring unit revealed no anomalies, and an examination of the helicopter revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation; therefore, the reason for the noise and vibration 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
- Miscellaneous/other during maneuvering defining event
- Autorotation Miscellaneous/other
- Abrupt maneuver during landing (flare/touchdown)
The NTSB's findings
- factor Not determined › Not determined › (general) › (general) › Unknown/Not determined
- Environmental issues › Physical environment › Terrain › Wet/muddy terrain › Not specified
Pilot
- Certificate: flight instructor, commercial pilot
- Ratings: single-engine sea; instructor: airplane single-engine; instructor: helicopter; instructor: instrument helicopter; instrument: airplane; instrument: helicopter; rotorcraft: helicopter
- Flight time: 1,750 hours in all; 200 in this make and model; 30 in the last 90 days; 15 in the last 30 days; 1,650 as pilot in command
- Last flight review: April 23, 2014
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: rgt
- Injury: no injuries
The aircraft
- Airframe total time: 400.0 hours
- Last inspection: annual inspection, October 15, 2015
- Maximum gross weight: 2,700 lb
- Seats: 5
- Landing gear: fixed
- Engine: Rolls-Royce 250-C300/A1 (turboshaft); 363 hours total
- Operator: Robinson Helicopter CO
The flight
- Departed from: TOA Torrance CA at 7:30 pm
- Destination: TOA Torrance CA
- Flight plan: none
Weather at the time
- Light: daylight
- Visibility: 10 statute miles
- Sky: scat at 20,000 ft
- Temperature: 84°F (29°C), dew point 36°F (2°C)
- Altimeter: 30.01 inHg
- Observation at 6:53 pm from KTOA
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
12 documents, released by the NTSB on April 10, 2017. 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, 9 pages | View Download |
| 2 | FAA Statements | PDF, 7 pages | View Download |
| 3 | NTSB Engine Examination | PDF, 4 pages | View Download |
| 4 | Flight Export Data | PDF, 17 pages | View Download |
| 5 | Rolls-royce Operating Manual Excerpt Use Approval | PDF, 3 pages | View Download |
| 6 | Rolls-royce Operating Manual Excerpt | PDF, 6 pages | View Download |
| 7 | Manufacturer's Explanation of the Failure | PDF, 1 page | View Download |
| 8 | Purpose of Flight | PDF, 1 page | View Download |
| 9 | Statement of Party Representatives to NTSB Investigation | PDF, 1 page | View Download |
| 10 | Release of Aircraft Wreckage, NTSB Form 6120.15 | PDF, 1 page | View Download |
| 11 | FAA Photos of A Sprag Clutch | PDF, 2 pages | View Download |
| 12 | Photos | PDF, 4 pages | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
Connections how this case links to the rest of the register
- N266RH on the register today · the tail number may have moved to another aircraft since
- Engine: Rolls-Royce 250-C300/A1 355 aircraft carry this series today · as the NTSB recorded it
- Zamperini Field · nearest airport
- Accidents and incidents in California 9,069 since 1982 · 1,087 in the last ten years
- California 27,686 aircraft registered
The whole map of how records connect · these connections as data: /graph/accident/WPR16LA075.json.
The bigger picture in Aviation Analytics: accidents over time since 1982, by model, by phase of flight and conditions, by place and on the map.
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 does not name anyone involved, its policy at this time. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.