NTSB Identification: DEN02FA076.
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Accident occurred Tuesday, July 16, 2002 in Ogden, UT
Probable Cause Approval Date: 04/18/2003
Aircraft: Wheeler Doug 2000, registration: N2058T
Injuries: 2 Fatal.
NTSB investigators either traveled in support of this investigation or conducted a significant amount of investigative work without any travel, and used data obtained from various sources to prepare this aircraft accident report.
Main rotor blade rpm was seen to slow as the pilot waited for landing traffic to clear the runway. The pilot was then cleared for takeoff on runway 34. Wind was reported to be from 320 degrees at 16 knots, gusting to 23 knots. Main rotor rpm was seen to increase as the gyroplane began its takeoff roll. After it had lifted off and climbed 200 to 400 feet, witnesses saw something separate from the gyroplane and it fall to the ground. An endorsement in the pilot's logbook indicated he was competent for "solo day flight...with winds less than 15 knots and crosswind component less than 8 knots." He was not rated in gyroplanes. Wreckage examination revealed the rectangular boxed beam tail boom was twisted and severed about 2 feet in front of the vertical stabilizer. The vertical stabilizer leading edge bore chop marks. The rudder was shattered. A diagonal crease mark was noted on the left surface of the vertical stabilizer, running from the upper leading edge to the lower trailing, near the tail wheel. Both rudder cables were severed. The outboard portions of all four pusher propeller blades were severed at the same angle. Both main rotor blades were bent downward at the hub, and one blade was severed. The pilot's toxicology screen was positive for nordiazepam, oxazepam, and temazepam. These are metabolites of benzodiazepine. The most common benzodiazepine, Valium, prescribed under the name of Restoril, is a tranquilizer used in the treatment of anxiety, and is contraindicated for flying. Since benzodiazepines were not detected in blood, the pilot most likely was not under its influence. The aircraft's flight manual gives the following warnings: "Attempting takeoff at full engine power with initial rotor speed less than 150 rpm will lead to blade flapping. In this condition the rotor will contact the ground."
The National Transportation Safety Board determines the probable cause(s) of this accident to be: the pilot's failure to obtain and maintain adequate main rotor rpm, resulting in blade flapping and subsequent blade contact with the airframe, severing of the tailboom, and causing loss of aircraft control. Contributing factors were the high gusty winds, and the pilot's lack of proper certification. Full narrative available
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