# NTSB DFW05CA142: Westland Wasp, N108RA, Denison, TX, May 30, 2005 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: May 30, 2005, 12:05 local (17:05 UTC) - Place: Denison, TX - Coordinates: 33.983333, -96.933334 - Nearby events: https://openairdocs.org/map.md?lat=33.9833&lon=-96.9333&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report September 13, 2005 - Report: Approved by Office Director - Parties: Federal Aviation Administration - NTSB case key (mKey): 61596 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DFW05CA142 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/61596/pdf - Page: https://openairdocs.org/ntsb/DFW05CA142 ## Probable cause The partial loss of engine power for undetermined reasons. A contributing factor was the lack of suitable terrain for the forced landing. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power, takeoff - initial climb - reason for occurrence undetermined (cause) - Forced landing, emergency landing after takeoff - Hard landing, emergency landing after takeoff - terrain condition - none suitable (contributing factor) - Gear collapsed, emergency landing after takeoff ## Analysis During initial climb-out on a southwesterly direction, while at an estimated altitude of 90 feet above the ground, and an estimated airspeed of 25 knots, the helicopter experienced an un-commanded reduction of engine power to flight idle. The 358-hour student pilot turned the helicopter 180 degrees, put the collective down, and applied right anti-torque pedal. The helicopter landed hard on a street, impacting on all four landing gear before bouncing back into the air. During the second ground impact, the left rear landing gear collapsed and the main rotor blades and tail rotor made contact with the ground. The winds at the time of the mishap were reported from 040 degrees at 8 knots. The reason for the reported loss of engine power could not be determined. ## Factual narrative On May 30, 2005, about 1205 central daylight time, a Westland Wasp turboshaft powered helicopter, N108RA, was substantially damaged following a partial loss of engine power during takeoff from private property near Denison, Texas. The student pilot and his passenger were not injured. The helicopter, for which an airworthiness certificate had not been issued, was registered to and operated by the pilot. Visual meteorological conditions prevailed and a flight plan was not filed for the 14 Code of Federal Regulations Part 91 personal flight. According to the 358-hour student pilot, during the initial climb-out in a southwesterly heading, at an altitude of approximately 90 feet above the ground, while at an estimated airspeed of 25 knots, the helicopter experienced an un-commanded reduction of engine power to flight idle. The pilot added that he turned the helicopter 180 degrees, placed the collective down, and applied right anti-torque pedal. The helicopter settled hard into a street, impacting on all four landing gear before bouncing back into the air. During the second ground impact, the left rear landing gear collapsed and the main rotor blades and tail rotor made contact with the ground. The pilot, who reports that he was operating the helicopter as a "public use" aircraft, reported to have accumulated all of his flight time in rotorcraft, with a total of 16.2 hours in the accident helicopter. The helicopter was manufactured in the United Kingdom by Westland Helicopter in 1965. The design consisted of an all-metal monocoque fuselage supported by four separate gear legs, each with a single wheel. Powering the four blade main rotor was a single 1,050 shaft horse power Rolls-Royce Nimbus 103 turboshaft engine. The helicopter was designed to carry one pilot and four passengers. N108RA was imported into the United States at an unknown date. A Federal Aviation Administration (FAA) inspector examined the wreckage. The inspector reported that the helicopter sustained structural damage to the fuselage. The reason for the reported uncommanded loss of engine power could not be determined. At 1145, the weather observation facility at Grayson County Airport (GYI), near Denison, Texas, located approximately 8 nautical miles southwest from the accident site, reported winds from 040 degrees at 8 knots, visibility 10 statute miles, scattered clouds at 2,200 feet and 3,100 feet, clouds broken at 3,800 feet, temperature 77 degrees Fahrenheit, dew point 66 degrees Fahrenheit, and barometric pressure setting of 29.88 inches of Mercury. ## Aircraft - Registration: [N108RA](https://openairdocs.org/deregistered/N108RA-2018-01-09), registration cancelled 2018-01-09, S/N 0001 (OpenAirDocs) - Reported make and model: Westland Wasp - Registry model: [Avery Rodger D AVERY WASP](https://openairdocs.org/model/avery-rodger-d-avery-wasp) (registry code 05619BS) (OpenAirDocs) - Category: Helicopter - Serial number: 0001 - Engines: Rolls-Royce Nimbus 103 turbo shaft - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Roger D Avery - Airworthiness certificate: Special, Restricted (Special) - Departed: Denison, TX - Destination: Denison, TX ## Flight crew As NTSB recorded them. NTSB leaves out names. - Student pilot; age 37; injuries: none; student; medical: class 3; flight hours: 358 total, 16 in this make and model, 16 in the last 90 days, 5 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 40° at 8 knots - Visibility: 10 statute miles - Lowest ceiling: 3,800 ft broken - Temperature: 77 °F, dew point 66 °F - Altimeter: 29.87 inHg ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20050530008539A](https://openairdocs.org/incident/20050530008539A), May 30, 2005: AVERYWASP, Denison, TX, Destroyed. (-23) The aircraft lifted-off from a field area located at [privacy data omitted] the aircraft got approximately 90 feet airborne when the aircraft engine went… From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.