Hughes 369HS accident near Fillmore, Utah, November 25, 2008
On November 25, 2008 at about 7:45 pm local time, a Hughes 369HS (helicopter), registered N9154F, was substantially damaged in an accident during enroute (cruise) near Fillmore, Utah. It was a business flight under general aviation rules (Part 91). 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
The loss of engine power due to fuel starvation as a result of a loose fuel filter upper drain cap, which was not properly secured by maintenance personnel.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- November 25, 2008 · about 7:45 pm local time
- Place
- Fillmore, Utah · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Hughes 369HS · all 369HSs on the register
- Registration
- N9154F · no longer on the register · serial 930517S
- Damage
- Substantial damage
- Flight
- Business flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
According to the pilot, during cruise flight the helicopter's engine lost power and it entered an autorotation. The helicopter was over mountainous/hilly terrain and there was no open place to land. The pilot selected a spot on a steep hill covered with 20- to 30-foot-tall oak trees. Upon touchdown, the helicopter began to roll, but was stopped by the vegetation. The tailboom incurred structural damage during the landing. Postaccident examination of the helicopter revealed that the fuel pump filter bowl's upper drain plug had been replaced with a non-standard threaded nipple fitting and cap. This cap was found with zero torque (loose) and partially backed off of its seat. Less than two threads retained the cap on its fitting. In standard configuration, the upper and lower drain plugs are lock-wired to each other, thus ensuring both fittings remain properly torqued. On the accident engine, the lower drain plug was lock-wired to the upper drain's threaded nipple fitting. However, the cap was not lockwired. The fuel spray nozzle's fuel supply line was found to be devoid of any residual fuel. (This line would typically have about 1 to 1.5 teaspoons of fuel following a normal engine shutdown.) The engine was removed from the airframe and shipped to the facilities of the engine manufacturer for a test run. The suspect loose cap was gently tightened with a wrench. The engine was then run and met all test cell parameters for new engine production. Since the fuel pump filter bowl operates at a negative pressure during operation, a compromise at this point in the fuel system would not result in a fuel leak, but would rather result in an air induction into the fuel system, interrupting the supply of fuel to the fuel spray nozzle.
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
- Aircraft maintenance event during prior to flight
- Fuel starvation during enroute (cruise)
- Loss of engine power (total) during enroute (cruise) defining event
- Autorotation Collision with terrain or object (not controlled flight into terrain)
The NTSB's findings
- cause Personnel issues › Task performance › Maintenance › (general) › Maintenance personnel
- cause Aircraft › Aircraft systems › Fuel system › Fuel filter › strainer › Incorrect service/maintenance
- Environmental issues › Physical environment › Terrain › Mountainous/hilly terrain › Contributed to outcome
Pilot
- Certificate: flight instructor, commercial pilot
- Ratings: single-engine land; instructor: helicopter; rotorcraft: helicopter
- Flight time: 5,749 hours in all; 895 in this make and model; 70 in the last 90 days; 43 in the last 30 days; 5,619 as pilot in command; 2,800 on instruments
- Last flight review: June 30, 2008
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 21,496 hours
- Last inspection: 100-hour inspection, November 18, 2008; 34 hours since
- Maximum gross weight: 2,550 lb
- Seats: 4
- Landing gear: fixed
- Engine: Allison 250 SER 400HP (turboshaft); 0 hours total
- Operator: Skyhawk Helicopter Service, INC.
The flight
- Departed from: RIF Richfield UT at 7:30 pm
- Destination: U77 Spanish Fork UT
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 210° at 10 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 61°F (16°C), dew point 21°F (-6°C)
- Altimeter: 30.00 inHg
- Observation at 9:52 pm from MLF, 45 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight 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.