Hiller UH-12E accident near Dixon, California, August 11, 1993
On August 11, 1993 at about 5:45 pm local time, a Hiller UH-12E (helicopter), registered N100LM, was destroyed in an accident near Dixon, California. It was an aerial application (crop spraying) flight under agricultural flying rules (Part 137). 1 person was seriously injured. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
the failure of the pilot to visually detect and avoid the guy wire.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 11, 1993 · about 5:45 pm local time
- Place
- Dixon, California · map
- Type
- Accident
- Injuries
- 1 person was seriously injured.
- Weather
- visual conditions (good weather)
- Aircraft
- Hiller UH-12E · all UH-12Es on the register
- Registration
- N100LM · registry record · serial 1583
- Damage
- Destroyed
- Flight
- Aerial application (crop spraying) flight · agricultural flying rules (Part 137)
The NTSB's narrative final · quoted from the NTSB record
AN FAA INSPECTOR SAID THE HELICOPTER HAD BEEN WORKING THE FIELD FOR ABOUT 2 HOURS DISPENSING INSECTICIDES. THE PILOT DEPARTED THE TRUCK AFTER REFUELING TO FINISH THE REMAINING CORNER OF THE FIELD BEING SPRAYED. THE FIELD IS BORDERED BY A SET OF POWER LINES ON WOODEN POLES WITH A WIRE HEIGHT ABOUT 40 FEET AGL. THE PILOT WAS FLYING UNDER THE POWER LINES DURING HIS SPRAY RUNS. THE LAST TWO POLES HAD A ONE QUARTER INCH GUY WIRE STRUNG BETWEEN THEM ABOUT HALF WAY UP THE POLES. ON THE FINAL PASS IN THE FIELD, THE HELICOPTER COLLIDED WITH THE GUY WIRE. BASED ON HIS INSPECTION OF THE WRECKAGE AND WITNESS OBSERVATIONS, THE FAA INSPECTOR REPORTED THAT THE HELICOPTER COLLIDED WITH THE WIRE AT A POINT BETWEEN THE ROTOR HUB AND THE SWASH PLATE ASSEMBLY, BREAKING THE PITCH CHANGE LINKS. THE PILOT WAS ABLE TO REGAIN PARTIAL CONTROL OF THE HELICOPTER AND WAS ATTEMPTING A RUN ON LANDING CROSS FURROW IN A TOMATO FIELD ABOUT TWO MILES FROM THE WIRE STRIKE. THE HELICOPTER SKIDS CAUGHT ON BOTH THE PLANTS AND THE SOFT FURROWS AND TUMBLED TO A STOP.
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: single-engine land; rotorcraft: helicopter
- Flight time: 6,500 hours in all; 650 in this make and model; 90 in the last 90 days; 40 in the last 30 days; 6,000 as pilot in command
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: ctr
The aircraft
- Airframe total time: 7,635 hours
- Last inspection: continuous airworthiness programme, August 8, 1993; 9 hours since
- Maximum gross weight: 2,750 lb
- Seats: 3
- Landing gear: fixed
- Engine: Allison 250 C20B (turboshaft); 0 hours total
- Operator: Pacific Valley Aviation, INC.
The flight
- Departed from: NONE at 5:25 pm
- Destination: NONE
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 240° at 6 knots
- Visibility: 25 statute miles
- Sky: scat at 2,500 ft
- Temperature: 66°F (19°C), dew point 54°F (12°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.
Other NTSB records under N100LM 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.