Summary
On July 03, 2010, a Wells Terry HULA GIRL (N301TW) was involved in an incident near Wellington, CO. All 1 person aboard were uninjured. The aircraft sustained substantial damage.
The National Transportation Safety Board determined the probable cause of this incident to be: A partial loss of engine power due to the inadequate design of the engine cowling.
The pilot, who is also the designer and builder of the experimental motorglider, was making his second flight after having completed a number of high-speed taxi tests. The pilot said that several months earlier, on his first flight in the motorglider, shortly after becoming airborne the engine experienced a partial loss of power and he landed immediately. On the accident flight, immediately after takeoff, the pusher-configuration engine again lost power from 6,500 rpm to approximately 4,300 rpm. The pilot was not able to climb and was able to maintain flight at only 100 feet above ground level. Approximately one mile from the airport the pilot attempted an off-field emergency landing and then “did an intentional ground loop” to avoid a fence he had not noticed before touchdown.
This incident is documented in NTSB report CEN10CA376. AviatorDB cross-references NTSB investigation data with FAA registry records to provide comprehensive safety information for aircraft N301TW.
Accident Details
Probable Cause and Findings
A partial loss of engine power due to the inadequate design of the engine cowling.
Aircraft Information
Registered Owner (Current)
Analysis
The pilot, who is also the designer and builder of the experimental motorglider, was making his second flight after having completed a number of high-speed taxi tests. The pilot said that several months earlier, on his first flight in the motorglider, shortly after becoming airborne the engine experienced a partial loss of power and he landed immediately. On the accident flight, immediately after takeoff, the pusher-configuration engine again lost power from 6,500 rpm to approximately 4,300 rpm. The pilot was not able to climb and was able to maintain flight at only 100 feet above ground level. Approximately one mile from the airport the pilot attempted an off-field emergency landing and then “did an intentional ground loop” to avoid a fence he had not noticed before touchdown. With the motorglider then moving sideways, the tail impacted a small tree. The carbon-fiber tail boom fractured and separated just forward of the vertical fin, causing substantial damage to the motorglider. The solo pilot was not injured. The pilot reported that there was adequate fuel in the tank and previous testing showed there was adequate fuel flow to the engine. After the accident the pilot reported that that his design of the engine cowling needed to be modified and he thought that “an engine compartment pressure differential from outside air caused the carburetor float bowl to empty.”
Data Source
Data provided by the National Transportation Safety Board (NTSB). For more information on this event, visit the NTSB Records Search website. NTSB# CEN10CA376