Texas Helicopter WASP/M74L accident near Petaluma, California, December 11, 1987
On December 11, 1987 at about 9:45 pm local time, a Texas Helicopter WASP/M74L, registered N51843, was substantially damaged in an accident near Petaluma, California. It was a business 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 NTSB has not yet published a probable cause for this accident. Investigations usually take one to two years; this page updates when the final report is released.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- December 11, 1987 · about 9:45 pm local time
- Place
- Petaluma, California · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Texas Helicopter WASP/M74L
- Registration
- N51843 · no longer on the register · serial 78-014
- Damage
- Substantial damage
- Flight
- Business flight · agricultural flying rules (Part 137)
The NTSB's narrative final · quoted from the NTSB record
DURING AN AERIAL APPLICATION FLIGHT, WHILE ON THE LAST PASS, THE AIRCRAFT STRUCK A POWER LINE THAT BECAME ENTANGLED IN THE ROTOR BLADES. THE PILOT WAS UNABLE TO MAINTAIN CONTROL OF THE AIRCRAFT AND COLLIDED WITH THE TERRAIN. THERE WERE NO REPORTED MECHANICAL FAILURES OR MALFUNCTIONS WITH THE AIRCRAFT PRIOR TO THE ACCIDENT.
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: 6,000 hours in all; 1,000 in this make and model; 80 in the last 90 days; 40 in the last 30 days; 5,800 as pilot in command
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: ctr
The aircraft
- Airframe total time: 1,291 hours
- Last inspection: annual inspection, November 6, 1987; 20 hours since
- Maximum gross weight: 2,800 lb
- Seats: 1
- Landing gear: fixed
- Engine: Lycoming VO-435-A1F (piston); 0 hours total
The flight
- Departed from: Petaluma CA at 9:00 pm
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 320° at 12 knots
- Visibility: 30 statute miles
- Sky: clear
- Temperature: 57°F (14°C), dew point 43°F (6°C)
- Altimeter: 30.00 inHg
- Observation at 9:45 pm from STS, 14 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.