Williams Helicopter CORP UH-1H accident near Colusa, California, August 30, 2024
On August 30, 2024 at about 2:05 pm local time, a 1965 Williams Helicopter CORP UH-1H, registered N710WD, was substantially damaged in an accident during maneuvering (hover) near Colusa, 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 pilot’s failure to set collective friction which resulted in collective bounce and subsequent loss of control.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 30, 2024 · about 2:05 pm local time
- Place
- Colusa, California · map
- Type
- Accident
- Injuries
- 1 person was seriously injured.
- Weather
- visual conditions (good weather)
- Aircraft
- Williams Helicopter CORP UH-1H, built 1965 · all UH-1Hs on the register
- Registration
- N710WD · registry record · serial 65-09761
- 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 pilot of the helicopter reported that while repositioning closer to the loading equipment, the helicopter experienced collective bounce. He attempted to maneuver the helicopter to avoid equipment and personnel; however, control was lost and the helicopter impacted terrain. The operator reported that there were no preaccident mechanical malfunctions or failures that would have precluded normal operations. The operators manual for the helicopter stated, in part, “Collective bounce is a pilot Induced vertical oscillation of the collective control system when an absolute friction (either pilot applied, or control rigged) is less than seven pounds. It may be encountered in any flight condition by a rapid buildup of vertical bounce at approximately three cycles per second. The seventy of the oscillation is such that effective control of the helicopter may become difficult to maintain. The pilot should apply and maintain adequate collective friction in all flight conditions.”
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
What happened, in order
- Loss of control in flight during maneuvering (hover) defining event
The NTSB's findings
- Personnel issues › Task performance › Use of equip/info › Use of equip/system › Pilot
- Personnel issues › Task performance › Use of equip/info › Aircraft control › Pilot
Pilot
- Certificate: commercial pilot
- Ratings: multi-engine land; single-engine land; single-engine sea; instrument: airplane; rotorcraft: helicopter
- Flight time: 13,000 hours in all; 22 in this make and model; 125 in the last 90 days; 50 in the last 30 days; 13,000 as pilot in command
- Last flight review: October 11, 2023
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: rgt
- Injury: serious injuries
The aircraft
- Last inspection: approved inspection programme
- Maximum gross weight: 9,500 lb
- Seats: 2
- Landing gear: fixed
- Engine: Ozark-Aeroworks T53-L-13B (turboshaft); 728 hours total
- Operator: A&P Helicopters INC
The flight
- Departed from: 07CL Richvale CA at 1:40 pm
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 130° at 3 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 70°F (21°C), dew point 54°F (12°C)
- Altimeter: 30.01 inHg
- Observation at 7:53 am from KOVE, 23 miles away
Weather report (METAR): METAR KOVE 301453Z AUTO 13003KT 10SM CLR 21/12 A3001 RMK AO2 SLP162 T02060122 53013=
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
4 documents, released by the NTSB on April 22, 2025. View them here, or download them; the NTSB redacts some personal details before release, and this site shows the NTSB's own titles rather than its file names.
| # | Document | What it is | |
|---|---|---|---|
| 1 | Pilot/operator Aircraft Accident Report, NTSB Form 6120.1 | PDF, 9 pages | View Download |
| 2 | Photos | PDF, 3 pages | View Download |
| 3 | Memorandum of Record - Operator | PDF, 1 page | View Download |
| 4 | UH-1H/V Operator's Manual (Tm 55-1520-210-10) Excerpt | PDF, 1 page | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
Other NTSB records under N710WD 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.