Colorado Aviation Accidents & Incidents

On May 29, 2001, at approximately 1845 mountain daylight time, an Enstrom F-28C helicopter, N83GT, sustained substantial damage when it landed hard following a total loss of engine power near Elizabeth, Colorado. The commercial certificated flight instructor and the private pilot receiving instruction were not injured. Visual meteorological conditions prevailed, and no flight plan had been filed for the local instructional flight being conducted under Title 14 CFR Part 91. The flight originated from Elizabeth, Colorado, at approximately 1745.

According to the instructor's statement, he was flying the helicopter and giving instruction on steep approaches to the private pilot. The instructor stated that during the demonstrated steep approach, they were in translation and at approximately 80 feet above ground level (AGL) when he noticed the rotor and engine RPM start to decay. The student pilot stated that, the instructor was giving him a visual reference between their indicated airspeed, which was approximately 50 MPH, and what the "picture on the ground" looked like. As the instructor continued the descent, the student pilot observed that the engine speed was at approximately 2900 RPM, and the manifold pressure indicated approximately 15 inches. The student pilot heard a change in rotor RPM and noticed that the both the rotor RPM and manifold pressures were dropping. We were "probably at 50 to 75 feet AGL with a visual ground speed of about 10 mph." The instructor stated "we are having an engine failure" lowered the collective control lever and increased the throttle. There was no reaction in manifold pressure and the main rotor RPM continued to decrease. The instructor landed the helicopter in a field just short of the intended landing point. The helicopter hit the ground at a higher than normal descent rate and the main rotor blades struck the tail boom, severing the tail rotor and tail rotor gearbox from the tailboom.

During an on site inspection of the helicopter, a manufacturer's representative from Textron-Lycoming stated that the helicopter engine compartment revealed no evidence of preaccident catastrophic mechanical malfunction or fire. There was no evidence of fuel or oil leakage from the engine, attached components, respective hoses, lines and fittings. The throttle and mixture controls were observed to "hit the stops" at their respective positions. The exhaust pipe exhibited a light gray discoloration and remained free of oil residue. The turbocharger turbine impellor remained intact and free of foreign object damage.

After completing the initial inspection, it was determined the engine was in an operable condition and an engine run-up and functional check could be completed. All systems were checked, and the main rotor drive belt was disengaged. The engine was started using normal procedures. The oil and fuel pressure gauges were within normal operating ranges. Manifold pressure was 10-11 inches Hg. After an initial wa