Hiller UH-12D accident near Walla Walla, Washington, July 4, 1990
On July 4, 1990 at about 2:15 pm local time, a Hiller UH-12D (helicopter), registered N62431, was substantially damaged in an accident near Walla Walla, Washington. 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
A LOSS OF ENGINE POWER FOR UNDETERMINED REASONS.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 4, 1990 · about 2:15 pm local time
- Place
- Walla Walla, Washington · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Hiller UH-12D · all UH-12Ds on the register
- Registration
- N62431 · no longer on the register · serial 956
- 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 HELICOPTER WAS SUBSTANTIALLY DAMAGED DURING A FORCED LANDING, WHEN THE SKIDS CAUGHT IN PEA VINES OF THE CROP THE PILOT WAS SPRAYING. HE STATED THAT THE ENGINE SUSTAINED A SUDDEN POWER LOSS. DURING A POST-ACCIDENT CHECK, THE ENGINE STARTED NORMALLY AND RAN TO 3200 RPM.
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; instructor: airplane multi-engine; instructor: airplane single-engine; instrument: airplane; rotorcraft: helicopter
- Flight time: 5,060 hours in all; 400 in this make and model; 250 in the last 90 days; 80 in the last 30 days
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: ctr
The aircraft
- Airframe total time: 9,084 hours
- Last inspection: annual inspection, January 10, 1990; 44 hours since
- Maximum gross weight: 2,750 lb
- Seats: 3
- Landing gear: fixed
- Engine: Lycoming VO-435-A1C (piston); 0 hours total
The flight
- Departed from: ALW Walla Walla WA at 12:30 pm
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 210° at 3 knots
- Visibility: 25 statute miles
- Sky: not recorded; not recorded
- Temperature: 61°F (16°C), dew point 0°F (-18°C)
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 N62431 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.