Hiller UH-12E (SOLOY) accident near Delano, California, May 10, 1984
On May 10, 1984 at about 6:00 pm local time, a Hiller UH-12E (SOLOY) (helicopter), registered N90461, was substantially damaged in an accident near Delano, California. It was an aerial application (crop spraying) flight under agricultural flying rules (Part 137). 1 person had minor injuries. 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
- May 10, 1984 · about 6:00 pm local time
- Place
- Delano, California · map
- Type
- Accident
- Injuries
- 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Hiller UH-12E (SOLOY) UH-12E (SO · all UH-12E (SOLOY)s on the register
- Registration
- N90461 · no longer on the register · serial 2514
- 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 EXPERIENCED AN INFLT FAILURE OF AN ENG MOUNT, PN 63181-5, WHICH BENT THE COLLECTIVE CONTROL ROD & FORCED THE THE COLLECTIVE PITCH INTO THE UP POSITION. THE HELICOPTER THEN SETTLED INTO THE GRAPES IT WAS SPRAYING & MADE A HARD LANDING. AN INVESTIGATION REVEALED THAT THE GUSSET WELD BEADS, JUST BELOW THE OUTER GIMBAL FORWARD ATTACH POINT, HAD FAILED IN FATIGUE.
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: 7,000 hours in all; 623 in this make and model; 162 in the last 90 days; 6,870 as pilot in command
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: rgt
The aircraft
- Airframe total time: 6,373 hours
- Last inspection: 100-hour inspection, June 28, 1983; 29 hours since
- Maximum gross weight: 8,700 lb
- Seats: 4
- Landing gear: fixed
- Engine: Allison 250-C20B (turboshaft); 0 hours total
The flight
- Departed from: DLO Delano CA at 5:30 pm
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Visibility: 20 statute miles
- Sky: clear
- Temperature: 73°F (23°C), dew point 0°F (-18°C)
- Altimeter: 29.00 inHg
- Observation at 5:50 pm from VIS, 39 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.