Evolution Inspection Recommendation

An Evolution owner recently contacted LOBO with the following incident involving a Foreign Object Debris (FOD) hazard:

My flight instructor and I were in Redmond last week for flight training with another CFI. On Sunday, after successful pre-flight, we taxied to the runway, and did the pre-takeoff checklist. Low and behold, we could not clear the “box”. The stick would move aft, right and left, full deflection, but we could not move the flight control stick forward of neutral. After playing with the stick, it was clear the forward constraint was a hard stop, like a big piece of metal blocking the forward deflection.

We taxied back to the hangar, shutdown and were unable to free the elevator from the hard stop. We felt it had to be some sort of FOD, perhaps a wrench or other tool, that was left where it shouldn't have been.

We dismantled every part of the path for the elevator controls and ultimately discovered a very small bolt wedged under the “Aft Torque Tube” located in the Torque Tube Pocket. The pictures below show the location in question.

EvoElevatorPushrod EvoElevatorPushrodControlHorn

It turns out there is an extremely small clearance between the bottom of the torque tube and the carbon fiber lining the bottom of the pocket. It is so small that even a very small foreign object--such as a bolt--can become wedged between the torque tube and the aircraft structure limiting or outright preventing movement of the elevator.

We think putting a small ridge in front of the torque tube would significantly reduce the possibility of FOD jamming the elevator.

Clearly this incident could have a much more disastrous outcome. LOBO encourages all Evolution owners to carefully inspect the area identified for any FOD that might interfere with control surface movement.

LOBO further encourages all Lancair owners to carefully inspect any area in the aircraft interior following maintenance to ensure all FOD is removed prior to flight, and to conduct all pre-takeoff checklists thoroughly and carefully. In this case, ensuring "All Controls Free" likely saved two lives.