Bell 47B3 accident near Redlands, California, February 16, 1990
On February 16, 1990 at about 2:30 pm local time, a Bell 47B3 (helicopter), registered N11HU, was destroyed in an accident near Redlands, California. It was a business 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
FAILURE OF THE PILOT TO USE CARBURETOR HEAT WHEN WARRENTED BY CONDITIONS.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- February 16, 1990 · about 2:30 pm local time
- Place
- Redlands, California
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Bell 47B3 · all 47B3s on the register
- Registration
- N11HU · registry record · serial 11
- Damage
- Destroyed
- Flight
- Business flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE OPERATOR BORROWED THE HELICOPTER FROM THE OWNER UNDER A VERBAL STIPULATION THAT AUTOMOTIVE FUEL WOULD NOT BE USED. THE ACCIDENT HELICOPTER WAS NOT APPROVED FOR AUTOMOTIVE GASOLINE UNDER THE PROVISIONS OF AN STC. HOWEVER, THE OPERATOR WAS KNOWN TO REFUEL HIS HELICOPTERS WITH AUTO GAS. THE PURPOSE OF THE FLIGHT WAS TO ERADICATE FROST FROM CITRUS TREES. AFTER REFUELING, THE HELICOPTER LOST POWER AND DESCENDED STRIKING WIRES AND TREES. THE OPERATOR DRAINED THE FUEL FROM THE HELICOPTER ON THE GROUND AND TRANSPORTED IT TO HIS FACILITY. THE ACCIDENT WAS REPORTED FOUR DAYS LATER. EXAMINATION OF THE FUEL SYSTEM REVEALED A SMALL QUANTITY OF FUEL WITH EVIDENCE OF AUTO GAS. LABORATORY ANALYSIS OF FUEL SAMPLE REVEALED SAMPLE HAD THE SAME AROMATIC QUALITIES AS AUTO GAS. ACCORDING TO THE FAA, THE ONSET OF CARBURETOR ICE WILL OCCUR QUICKER WITH AUTO GAS THAN WITH AVIATION FUEL. WEATHER CONDITIONS WERE CONDUCIVE TO FROST FORMING ON FRUIT TREES.
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: commercial pilot, private
- Ratings: single-engine land; instructor: helicopter; rotorcraft: helicopter
- Medical certificate: Class 2
- Seat: left
The aircraft
- Airframe total time: 12,000 hours
- Last inspection: inspection type not recorded, January 11, 1990; 70 hours since
- Maximum gross weight: 1,950 lb
- Seats: 2
- Landing gear: fixed
- Engine: Franklin 6V4 200 C32 (piston); 0 hours total
The flight
- Flight plan: none
- Runway 0
Weather at the time
- Light: dawn
- Visibility: 20 statute miles
- Sky: scat at 15,000 ft
- Temperature: 34°F (1°C), dew point 19°F (-7°C)
- Altimeter: 30.00 inHg
- Observation at 1:57 pm from SBD, 9 miles away
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.
Other NTSB records under N11HU the same tail number, which may have belonged to a different aircraft at the time
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.