CEN16LA245

The student pilot and flight instructor were returning to the airport to land following an instructional flight in the weight-shift aircraft. The flight instructor performed the approach and landing, and, upon touchdown, the engine power increased. The aircraft lifted off the runway, drifted toward the right side of the runway, began a mild oscillation, then impacted the ground. Postaccident examination revealed no evidence of mechanical malfunctions or anomalies that would have precluded normal operation; the trim position was set to "fast." According to the aircraft operating instructions, when the aircraft is trimmed in the "fast" setting, the pilot would be required to apply more pressure on the controls in order to slow the aircraft down. The operating instructions indicated that the trim should be set to a "slow" position during landing. It is likely that the flight instructor experienced greater than expected control forces and difficulty in slowing the aircraft during landing due to its improper trim setting. This subsequently led to his loss of control during landing.

On June 29, 2016, at 1900 eastern daylight time, an Evolution Aircraft Inc. Revo, weight-shift aircraft, N20EV, impacted terrain during landing at Park Township Airport (HLM), Holland, Michigan. The airplane sustained substantial damage. The flight instructor received serious injuries, and a student pilot received minor injuries. The aircraft was registered to and operated by Twilight Aviation under 14 Code of Federal Regulations Part 91 as an instructional flight that was not operating on a flight plan. Visual meteorological conditions prevailed for the local flight that originated at 1800. The operator/student pilot stated that purpose of the training flight was to receive instruction on straight and level flight. The operator stated that the student pilot and the flight instructor performed "some" straight and level flying during the flight with the flight instructor demonstrating S-turns. The student pilot then took the flight controls and they flew to HLM, and as the airplane approached HLM, the flight instructor took the flight controls. The flight instructor flew the aircraft into a left-hand airport traffic pattern and about 700 feet above ground level, he made an approach to landing for runway 23. The aircraft touched down on the runway, and then the engine "seemed to go to full throttle." The aircraft then lifted "slightly," about 10 feet above the runway, and ceased to climb. The aircraft drifted right and over a grass area on the right side of the runway. The aircraft still did not climb and began a "mild oscillation." The student pilot said they were "rapidly running out of runway," and the aircraft hit the ground "very hard," ending up on its side. The student pilot stated that that earlier in the flight, he had asked the flight instructor what was the trim position. The student pilot said the flight instructor told him that the trim position was in the "fast" position. The student pilot said that after recovery of the aircraft wreckage, the trim was in the "fast" position. The student pilot stated there was no mechanical malfunction/failure of the aircraft. Post-accident examination of the aircraft by a Federal Aviation Administration inspector revealed that the trim position was in the fast position, and the examination also confirmed flight control continuity. According to the Evolution Aircraft Inc. Aircraft Operating Instruction and Flight Training Supplement - Evolution Aircraft, Inc Rev 7.0, the electric in-flight speed trim is an option that allows the pilot to fly hands off by changing the speed of the wing with the push of a momentary switch. The electric in-flight speed trim shifts the entire hang block fore and aft on the keel. It is important to understand that this system only relieves the pilot's arms from holding the bar in a position that may be different then a fixed hang point trim speed. In no way can it over-ride the pilot's input. To use the speed trim press and hold the momentary switch. Holding down theswitch will pull the hang block forward and shift the center-of-gravity of the wing forward causing it to trim faster. Holding up the switch will allow the hang block to slide back and shift the center of gravity of the wing aft causing it to trim slower. Takeoff in a full fast trim setting will require much more pressure to push the control bar forward. The control bar is the best indicator of where the trim is set when in flight. It is also possible to simply look up and note the position of the hang block between the stops for trim setting. Setting the trim for landing position is similar to the takeoff position. Landing in full slow trim however, will require more pressure to pull the control bar in. The supplement states that if the electric speed trim is not set properly, it will require more pressure to slow the aircraft down when trimmed fast and more pressure to maintain higher air speed when trimmed slow which may be taxing to the body. Ultimately, the pilot controls the speed not the trim setting of the aircraft. A review of the aircraft checklist showed that the trim setting was an aircraft checklist item for phases of flight that included descent and landing.