Bell 206B accident near Delhi, California, September 1, 1999
On September 1, 1999 at about 1:15 pm local time, a Bell 206B (helicopter), registered N59551, was substantially damaged in an accident near Delhi, California. It was an aerial application (crop spraying) flight under agricultural flying rules (Part 137). 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 loss of engine power due to the pilot's inadequate preflight, which failed to detect water contamination of the fuel system. The operator's inadequate maintenance of the loose fitting fuel cap and the deformed filler opening, which allowed water to leak into the fuel tank, were also causal. A factor in the accident was the trees along the autorotative flight path, which required the pilot to stretch the glide and resulted in a low main rotor rpm situation for the landing flare.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- September 1, 1999 · about 1:15 pm local time
- Place
- Delhi, California
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Bell 206B · all 206Bs on the register
- Registration
- N59551 · no longer on the register · serial 1392
- Damage
- Substantial damage
- Flight
- Aerial application (crop spraying) flight · agricultural flying rules (Part 137)
The NTSB's narrative final · quoted from the NTSB record
The pilot reported that the engine rpm began decreasing during the takeoff climb, about 200 to 300 feet agl, while he was over a grove of trees. He extended his autorotative glide to make it past the trees, which resulted in a further decrease of main rotor rpm. The helicopter landed hard, about 20 to 30 miles per hour of forward velocity, and rolled over. Postcrash examination by a FAA inspector revealed no evidence of mechanical malfunction; however, the fluid found in the airframe fuel filter and mechanical fuel pump screen was noted to be about 90 percent water. About 30 percent of the fluid found in the Ceco fuel system screen was also water. The FAA inspector reported that the fuel cap was loose in the opening and did not appear to seal properly; the shaft seal was worn in the cap and the cap locking mechanism was not adjusted properly. When the fuel cap was removed, the inspector noted that the bottom of the fuel filler opening was deformed from the fuel nozzles being inserted in the opening. The pilot reported that he had washed the helicopter the night before the accident. He further reported that during the preflight he had drained fuel from the airframe fuel filter and fuel sump and hadn't noted any water or contaminants.
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
- Ratings: multi-engine land; single-engine land; single-engine sea; rotorcraft: helicopter
- Flight time: 10,000 hours in all; 1,000 in this make and model; 100 in the last 90 days; 60 in the last 30 days; 9,888 as pilot in command
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: rgt
The aircraft
- Airframe total time: 10,263 hours
- Last inspection: annual inspection, September 4, 1998; 89 hours since
- Maximum gross weight: 3,200 lb
- Seats: 5
- Landing gear: fixed
- Engine: Allison 250-C20 (turboshaft); 0 hours total
The flight
- Flight plan: none
- Runway 0
Weather at the time
- Light: dawn
- Wind: from 320° at 3 knots
- Visibility: 10 statute miles
- Sky: not recorded; scat at 10,000 ft
- Temperature: 52°F (11°C), dew point 45°F (7°C)
- Altimeter: 29.00 inHg
- Observation at 12:53 pm from MCE, 16 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.
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.