Boeing 369E accident near Taft, California, November 30, 1999
On November 30, 1999 at about 9:45 pm local time, a Boeing 369E (helicopter), registered N5238C, was substantially damaged in an accident near Taft, California. It was an other work-use flight under external-load helicopter rules (Part 133). 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 fatigue failure of a second stage compressor vane due to erosion, which resulted in a catastrophic engine failure. An inadequate inspection of the compressor section by company maintenance personnel during the last 300-hour inspection was also causal in this accident. The maintenance personnel's failure to conduct the periodic recommended compressor washes was a factor.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- November 30, 1999 · about 9:45 pm local time
- Place
- Taft, California · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Boeing 369E
- Registration
- N5238C · registry record · serial 0151E
- Damage
- Substantial damage
- Flight
- Other work-use flight · external-load helicopter rules (Part 133)
The NTSB's narrative final · quoted from the NTSB record
During a forced landing after an engine failure, the helicopter struck a standpipe, shearing its cross tube, and rolling onto its side. The pilot was in the process of picking up an 800-pound sling load on a 100-foot-long line. As his load reached about 90 to 100 feet agl, the engine quit. He released his load, turned to the right to avoid people and equipment on the ground, and entered autorotation. The conditions at the accident site were dusty and gritty. The engine teardown revealed that a second stage compressor vane had failed in fatigue, which resulted in a catastrophic failure of the compressor section. All first stage vanes were intact, and all third, fourth, fifth, and sixth stage vanes exhibited some degree of foreign object damage (FOD). The plastic coating on the first and second stage vanes exhibited erosion that exceeded the maximum allowable limits specified by the Rolls-Royce Allison 250-C20 Series Operation and Maintenance Manual. The first stage compressor blades were eroded, with the leading edges rolled over and scalloped. Metallurgical examination of the failed vanes revealed that they met all chemical and manufacturing process specifications. According to the maintenance records, a 300-hour inspection had been performed on the engine 130.1 flight hours before the accident. The manufacturer recommends a compressor case inspection be accomplished every 300 hours when operating in a corrosive environment. No evidence was found in the maintenance records of compressor washes being performed as recommended by the manufacturer.
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: instrument: helicopter; rotorcraft: helicopter
- Flight time: 8,000 hours in all; 5,700 in this make and model; 7,000 as pilot in command
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 2,548 hours
- Last inspection: 100-hour inspection, November 3, 1999; 62 hours since
- Maximum gross weight: 3,500 lb
- Seats: 4
- Landing gear: fixed
- Engine: Rolls-Royce 250-C20 (turboshaft); 0 hours total
The flight
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 360° at 4 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 156°F (69°C), dew point 115°F (46°C)
- Altimeter: 30.00 inHg
- Observation at 8:56 pm from BFL, 25 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.