Robinson R-22B accident near Lakeport, California, April 11, 1995
On April 11, 1995 at about 5:48 pm local time, a Robinson R-22B (helicopter), registered N4015Y, was substantially damaged in an accident near Lakeport, California (Lampson Field). It was an instructional 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 student's misjudged landing flare and his failure to verify the validity of the low rotor warning. Factors in the accident were the company management's continued use of the helicopter in flight training operations with a known discrepancy in the main rotor warning system, and the soft nature of the soil at the autorotation landing area.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- April 11, 1995 · about 5:48 pm local time
- Place
- Lakeport, California · Lampson Field · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Robinson R-22B · all R-22Bs on the register
- Registration
- N4015Y · no longer on the register · serial 1427
- Damage
- Substantial damage
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE STUDENT WAS DOING TAKEOFFS AND LANDINGS IN THE TRAFFIC PATTERN WHEN THE LOW ROTOR RPM WARNING HORN ACTIVATED. THE STUDENT WAS UNSUCCESSFUL IN EXTINGUISHING THE WARNING HORN BY THROTTLE AND COLLECTIVE MANIPULATION AND ENTERED AN AUTOROTATION. THE STUDENT DID NOT VERIFY THE MAIN ROTOR RPM BY THE ROTOR TACHOMETER. DURING THE TOUCHDOWN, ABOUT 1/4-MILE SOUTHEAST OF THE AIRPORT IN A SOFT FIELD, THE SKIDS DUG INTO SOFT SOIL AND THE HELICOPTER ROLLED OVER. A FAA INSPECTOR EXAMINED THE AIRCRAFT AND ENGINE, WHICH INCLUDED AN ENGINE START AND STATIC RUN-UP. THE ENGINE STARTED NORMALLY AND WAS EXERCISED THROUGHOUT ITS NORMAL POWER RANGE. MAINTENANCE RECORDS REVEALED A HISTORY OF FALSE LOW ROTOR RPM WARNING HORN ACTIVATIONS IN THE HELICOPTER DATING BACK 9 MONTHS. AFTER PILOTS WOULD REPORT THE WARNING HORN DISCREPANCY TO MAINTENANCE PERSONNEL, A SYSTEM COMPONENT WOULD BE CHANGED AND THE HELICOPTER RETURNED TO SERVICE; HOWEVER, THE PROBLEM PERSISTED. THE CFI'S SAID THEY TRAINED THE STUDENTS, INCLUDING THE ACCIDENT PILOT, HOW TO COPE WITH THE NUISANCE WARNING.
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: student
- Flight time: 40 hours in all; 40 in this make and model; 40 in the last 90 days; 40 in the last 30 days
- Medical certificate: Class 3 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Last inspection: annual inspection, July 30, 1994
- Maximum gross weight: 2,400 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming O-290 (piston); 0 hours total
- Operator: Resort Aviation
The flight
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Visibility: 50 statute miles
- Temperature: 57°F (14°C), dew point 0°F (-18°C)
- Altimeter: 30.00 inHg
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 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.