ASN Wikibase Occurrence # 285005
This information is added by users of ASN. Neither ASN nor the Flight Safety Foundation are responsible for the completeness or correctness of this information.
If you feel this information is incomplete or incorrect, you can submit corrected information.
| Date: | Tuesday 24 April 2007 |
| Time: | 07:30 LT |
| Type: |  Hughes 369D |
| Owner/operator: | Aerial Solutions Incorporated |
| Registration: | N11AS |
| MSN: | 790541D |
| Year of manufacture: | 1979 |
| Total airframe hrs: | 7639 hours |
| Engine model: | Allison/Rolls Royce 250-C20B |
| Fatalities: | Fatalities: 0 / Occupants: 2 |
| Aircraft damage: | Substantial |
| Category: | Accident |
| Location: | Whiteville, North Carolina -
 United States of America
|
| Phase: | Unknown |
| Nature: | Private |
| Departure airport: | Whiteville-Columbus County Municipal Airport, NC (KCPC) |
| Whiteville-Columbus County Municipal Airport, NC (KCPC) | |
| Investigating agency: | NTSB |
| Confidence Rating: |  Accident investigation report completed and information captured |
According to the pilots, the helicopter was at an altitude between 400 and 500 feet above ground level and at an airspeed between 75 and 80 knots when the engine lost power. The instructor-pilot took control of the helicopter, jettisoned the external load, and autorotated to a nearby corn field. He said that the engine "didn't sound like it was running and the engine out was activated." The helicopter touched down and slid 6 to 8 feet when one of the skids dug into the earth. The helicopter turned to the left about 45 degrees and rolled over on its right side. It was later found that the power turbine governor (PTG) spring had fractured in fatigue. The fracture originated from a drawing mark and was the result of deficiencies in the manufacturing process. The PTG spring "provides force opposing those exerted by rotating flyweights on the position of the governor lever. Failure of the spring would result in a false pneumatic signal to the fuel control and a corresponding reduction in fuel flow. The effect of the false pneumatic signal would be a pronounced reduction in fuel flow. At the reduced fuel flow, the engine could not sustain flight, and the symptoms of the reduced fuel flow might easily be interpreted by the pilot as an engine failure."
Probable Cause: A partial loss of engine power due to fatigue fracture of the power turbine governor spring, causing a false pneumatic signal to the fuel control and a corresponding reduction in fuel flow.
Accident investigation:
 |
|
Sources:
NTSB ATL07LA079
Revision history:
| Date/time | Contributor | Updates |
|---|---|---|
| 01-Oct-2022 16:30 | ASN Update Bot | Added |
Corrections or additions? ... Edit this accident description
The Aviation Safety Network is an exclusive service provided by:
Quick Links:
| ASN Home | Send Correction / Feedback |
| FSF Home | Disclaimer | Copyright |
| Contact Us | Privacy Policy |
| Press / Media |
CONNECT WITH US:
©2024 Flight Safety Foundation