Boeing Helicopters Div. H500D accident near Union Gap, Washington, July 24, 2001
On July 24, 2001 at about 11:00 pm local time, a Boeing Helicopters Div. H500D, registered N8964T, was substantially damaged in an accident near Union Gap, Washington. It was a public-use flight under public-use (government) rules. No one was hurt; 3 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The complete loss of engine power at cruise for undetermined reasons. Factors include a landing area that was restricted/confined due to adjacent trees, and an intentional abrupt flare resulting in a hard landing.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 24, 2001 · about 11:00 pm local time
- Place
- Union Gap, Washington · map
- Type
- Accident
- Injuries
- No one was hurt; 3 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Boeing Helicopters Div. H500D
- Registration
- N8964T · no longer on the register · serial 1038D
- Damage
- Substantial damage
- Flight
- Public-use flight · public-use (government) rules
The NTSB's narrative final · quoted from the NTSB record
While cruising at 1,000 feet above the ground, the helicopter encountered an area of strong updrafts and downdrafts. As it passed through one particularly strong downdraft, the aircraft experienced a complete loss of power. The pilot then initiated an autorotation to the only available landing area. Because the area was small and surrounded by trees, the pilot found it necessary to execute an abrupt flare in order to arrest the forward movement of the helicopter prior to colliding with the trees ahead. The abrupt flare resulted in a hard landing, and the main rotor blades flexed downward far enough to sever the tail boom. Post-accident inspections of the engine and aircraft systems did not reveal any malfunctions or anomalies that would have been expected to contribute to a loss of power. Although the flight manual warned of possible fuel starvation associated with large side slip angles of uncoordinated flight with less than 35 pounds of fuel remaining, approximately 115 pounds of fuel were drained from the helicopter's main fuel bladder.
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: airline transport pilot
- Ratings: multi-engine land; single-engine land; instrument: airplane; instrument: helicopter; rotorcraft: helicopter
- Flight time: 6,199 hours in all; 1,045 in this make and model; 152 in the last 90 days; 87 in the last 30 days; 5,742 as pilot in command
- Last flight review: May 7, 2001
- Medical certificate: Class 1 (valid medical--w/ waivers/lim.)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 3,369 hours
- Last inspection: annual inspection, June 15, 2001; 39 hours since
- Maximum gross weight: 3,000 lb
- Seats: 3
- Landing gear: fixed
- Engine: Allison 250C20B (turboshaft); 0 hours total
The flight
- Departed from: YKM Yakima Air Term WA at 8:20 pm
- Flight plan: none
Weather at the time
- Light: daylight
- Visibility: 20 statute miles
- Sky: clear
- Temperature: 95°F (35°C), dew point 64°F (18°C)
- Altimeter: 29.89 inHg
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 2 |
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.