Robinson R22A accident near Piru, California, February 10, 1991
On February 10, 1991 at about 11:20 pm local time, a Robinson R22A (helicopter), registered N8491A, was substantially damaged in an accident near Piru, California. It was an instructional flight under general aviation rules (Part 91). No one was hurt; 2 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
FAILURE OF THE CFI TO MAINTAIN MAIN ROTOR RPM DURING A DEMONSTRATED AUTOROTATION.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- February 10, 1991 · about 11:20 pm local time
- Place
- Piru, California · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Robinson R22A · all R22As on the register
- Registration
- N8491A · registry record · serial 0404
- Damage
- Substantial damage
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE CFI WAS DEMONSTRATING A 180 DEGREE AUTOROTATION TO HIS STUDENT IN A 25 KT WIND. THE CFI ALLOWED THE MAIN ROTOR RPM TO BLEED OFF AND WAS UNABLE TO RECOVER THE RPM BEFORE TOUCHDOWN. THE HELICOPTER LANDED HARD AND THE MAIN ROTOR SEVERED THE TAILBOOM. THE HELICOPTER THEN ROLLED OVER.
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
Pilot
- Certificate: flight instructor, commercial pilot
- Ratings: instructor: helicopter; rotorcraft: helicopter
- Flight time: 2,370 hours in all; 2,351 in this make and model; 167.1 in the last 90 days; 102.5 in the last 30 days; 2,290 as pilot in command; 2,100 on instruments
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: unk
The aircraft
- Airframe total time: 6,154 hours
- Last inspection: 100-hour inspection, January 12, 1991; 37 hours since
- Maximum gross weight: 1,370 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming O-320-B2C (piston); 0 hours total
- Operator: Watson Helicopters INC.
The flight
- Departed from: WHP Pacoima CA at 10:15 pm
- Flight plan: none
- Runway 0
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 275° at 25 knots
- Visibility: 30 statute miles
- Sky: clear
- Temperature: 75°F (24°C), dew point 0°F (-18°C)
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 2 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
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.