Incident Summary
On June 15, 2011, at 1450 central daylight time, a Schweizer 269C, registration N2077E, operated by the University of North Dakota, sustained substantial damage to the tailboom while recovering from a practice autorotation. The flight was conducted under 14 Code of Federal Regulations Part 91 as an instructional flight in visual meteorological conditions without a flight plan. The local flight originated from Grand Forks International Airport (GFK), Grand Forks, North Dakota, at 1430.
Flight Details
The certified flight instructor and the student pilot were not injured. The helicopter was equipped with an Appareo RMS-2000 flight data recorder, data from which was included in the docket for the report.
Sequence of Events
The flight instructor and student were performing a simulated forced landing intended to terminate with power. The student lowered the collective to enter the autorotation and set the trim and pitch to maintain the recommended airspeed. The instructor adjusted the collective during the autorotation to prevent an overspeed. The student began the flare at an altitude of about 50 feet above the ground. The instructor stated that the rotor revolutions per minute (rpm) were within the green arc and the engine was at 2,600 rpm.
The student used the collective to reduce forward speed and rate of descent. Engine power was then increased to recover from the autorotation, and the instructor noted the engine rpm needle moving up through 3,000 rpm. The instructor reported that the helicopter was slightly tail low and yawed slightly as power was increased. The instructor took over the controls to level the skids and straighten the heading as the helicopter continued to sink. The helicopter continued to descend, making a "light touch down" and run-on landing. During the level-off and ground contact, the instructor reported hearing a metal-on-metal sound.
Postaccident Inspection
Postaccident inspection revealed that two of the main rotor blades had contacted the tailboom.