Robinson R22A accident near El Cerrito, California, July 11, 1991
On July 11, 1991 at about 6:00 pm local time, a Robinson R22A (helicopter), registered N4070H, was substantially damaged in an accident near El Cerrito, California. It was an instructional flight under general aviation rules (Part 91). 1 person was seriously injured and 1 person had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
THE INSTRUCTOR PILOT'S IMPROPER SLOPE TAKEOFF TECHNIQUE.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 11, 1991 · about 6:00 pm local time
- Place
- El Cerrito, California
- Type
- Accident
- Injuries
- 1 person was seriously injured and 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Robinson R22A · all R22As on the register
- Registration
- N4070H · no longer on the register · serial 1727
- Damage
- Substantial damage
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE INSTRUCTOR PILOT WAS DEMONSTRATING SLOPE TAKEOFF TECHNIQUES TO THE STUDENT AFTER THE STUDENT HAD LANDED ON A HILLSIDE THAT SLOPED DOWNWARD FROM LEFT TO RIGHT. THE INSTRUCTOR LIFTED THE HELICOPTER'S RIGHT DOWN SLOPE SKID TWICE WHILE THE LEFT SKID REMAINED ON THE GROUND. DURING THE THIRD LIFT-OFF THE INSTRUCTOR DID NOT LIFT THE LEFT SKID AS THE HELICOPTER RAISED AND IT ROLLED OVER UPSLOPE ON ITS LEFT SIDE.
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: single-engine land; instructor: helicopter; rotorcraft: helicopter
- Flight time: 420 hours in all; 316 in this make and model; 205 in the last 90 days; 78 in the last 30 days; 302 as pilot in command; 194 on instruments
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Last inspection: 100-hour inspection, July 9, 1991; 10 hours since
- Maximum gross weight: 1,370 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming O-320 (piston); 0 hours total
- Operator: Para Flite, INC.
The flight
- Departed from: RAL Riverside CA
- Flight plan: none
- Runway 0
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 280° at 9 knots
- Visibility: 3 statute miles
- Temperature: 0°F (-18°C), dew point 0°F (-18°C)
- Altimeter: 29.00 inHg
- Observation at 6:50 pm from RAL, 17 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | 1 |
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.