# NTSB SEA01LA009: Hallett HALLETT-1, N8331H, Yelm, WA, October 21, 2000 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: October 21, 2000, 13:45 local (20:45 UTC) - Place: Yelm, WA - Coordinates: 46.870506, -122.56919 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=46.8705&lon=-122.5692&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report July 2, 2001 - Report: Approved by Office Director - NTSB case key (mKey): 50541 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA01LA009 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/50541/pdf - Page: https://openairdocs.org/ntsb/SEA01LA009 ## Probable cause The pilot's failure to abort the takeoff when it became questionable as to whether the aircraft would be able to clear an object just off the departure end of the runway, and the pilot's failure to maintain clearance from the object as he attempted to continue the departure. Factors include operating with a known engine deficiency, and a power line strung just off the departure end of the runway. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight collision with object, takeoff - aborted takeoff - not performed, pilot in command (cause) - clearance - not maintained, pilot in command (cause) - operation with known deficiencies in equipment - intentional, pilot in command (contributing factor) - object - wire,transmission (contributing factor) ## Analysis The pilot, who was aware that the engine on his gyroplane had not been producing the expected maximum full power, attempted a takeoff at an airstrip which had a marked power line just off the departure end of the runway. After liftoff, the aircraft climbed at a very shallow angle, and by the time it had proceeded more than 90 percent of the way down the runway, it had not climbed higher than the subject obstacle. Instead of aborting the takeoff, the pilot tried to increase the aircraft's angle of climb. As the gyroplane neared the end of the runway, it seemed to the pilot that its power output was decreasing, and he became convinced that he might not be able to clear the power line. He therefore attempted to fly under the marked line, but impacted an unmarked line strung lower on the poles. ## Factual narrative On October 21, 2000, approximately 1345 Pacific daylight time, an experimental Hallett-1 gyroplane, N8331H, collided with a power line during takeoff from Flying "B" Airport, Yelm, Washington. The private pilot, who was the sole occupant, was not injured, but the aircraft, which was owned and operated by the pilot, sustained substantial damage. The 14 CFR Part 91 local personal pleasure flight, was being operated in visual meteorological conditions. No flight plan had been filed. The aircraft did not carry an ELT. A video of the takeoff shows that after liftoff, the aircraft climbed at a very shallow angle. When asked about this in a post-accident telephone interview, the pilot stated that for a number of hours prior to the attempted takeoff, the gyroplane's engine had been running lean and hot, and had therefore not been producing the expected maximum power. As it reached a point where the aircraft was approximately 90 percent of the way down the runway, it still had not reached an altitude equal to the height of the marked power line off the departure end. Instead of aborting the takeoff at that point, the pilot continued the takeoff sequence and attempted to increase the gyroplanes angle of climb. According to the pilot, as he neared the departure end of the runway, it seemed to him that the engine's power output began to decay. Believing that he would not be able to clear the power line, he attempted to fly underneath it. Although he missed the marked main transmission wire, he did not see that there was a smaller unmarked wire strung further down the pole. As he maneuvered to miss the main wire, the rotor mast of the gyroplane contacted the lower wire, stopping the rotation of the main rotor. Immediately after the main rotor hit the wire, the aircraft dropped about 10 feet onto the surface of an adjacent road. ## Aircraft - Registration: [N8331H](https://openairdocs.org/deregistered/N8331H-2017-05-23), registration cancelled 2017-05-23, S/N SN-101, built 2000 (OpenAirDocs) - Reported make and model: Hallett HALLETT-1 - Registry model: [Hallett Thomas E HALLETT-1](https://openairdocs.org/model/hallett-thomas-e-hallett-1) (registry code 05625KJ) (OpenAirDocs) - Registry engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999) (OpenAirDocs) - Category: Gyroplane, amateur-built - Serial number: 101 - Airframe hours: 10 - Engines: Hirth 2703 R 03E 50 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Thomas E. Hallett - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Continuous airworthiness, August 1, 2000, 6 hours before - Departed: 8WA0 - Airport: 8WA0, Flying B, runway 31, 2,200 × 60 ft, grass/turf ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 65; private; airplane ratings: multi-engine land, single-engine land; medical: class 3, valid medical--w/ waivers/lim; seat: center; flight hours: 1,180 total, 10 in this make and model, 1,180 as pilot in command, 10 in the last 90 days, 4 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 270° at 3 knots - Visibility: 20 statute miles - Lowest ceiling: none - Temperature: 61 °F, dew point 45 °F - Altimeter: 29.00 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 20001021041099A](https://openairdocs.org/incident/20001021041099A), Oct 21, 2000: Rainier, WA, No damage. (-23)Pilot departed Flying B Airport, at yelm, Washington, and struck a power line during the initial climb. Pilot told NTSB personnel that he "lost power" and… 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.