Accident Sequence
A solo certificated commercial pilot departed for another airport about 5 miles away. During the takeoff roll, as the airplane's airspeed approached 60 knots, the pilot applied aft control yoke pressure to rotate the nose. When the desired pitch angle was attained, she released the back pressure, but the yoke failed to move forward. The airplane then pitched up uncontrollably, prompting the pilot to disengage the electric trim due to concerns about a runaway trim condition. She regained control but noted very limited aileron and elevator range of motion and elected to continue straight ahead to her next scheduled stop. She attempted to transmit a "mayday" but the radio transmit button on the pilot's control yoke was inoperative. During the short flight, she managed altitude and airspeed by adjusting engine power.
Approaching the accident airport, she used a combination of engine power, rudder, and the remaining aileron control to maneuver for landing on runway 05. As the airplane passed over the approach end of the runway, she attempted to flare before touchdown. The nose of the airplane failed to rise, and the nose wheel struck the gravel-covered runway. The nose landing gear collapsed, and the airplane bounced off the right side of the runway.
Postaccident Findings
A postaccident examination of the control yoke mechanism behind the instrument panel revealed that a wiring harness had become entangled in a series of roller bearings associated with the control yoke mechanism. Subsequent inspection disclosed that the accident airplane's control column did not have a required STA-Strap, part number S-2209-2, installed. Proper installation of the required STA-Strap would have provided adequate clearance between the wiring harness and the control yoke roller bearings. The roller bearing assembly was disassembled, and the entangled wiring harness was removed. The correct length for the factory installed wiring harness is 49 inches, but the removed harness measured 34 inches.
Maintenance Background
Review of the airplane's maintenance history revealed no maintenance activity concerning the control yoke assembly. The operator had owned the airplane for about 11 years. The airplane had been added to the operator's Approved Aircraft Inspection Program (AAIP) on February 11, 2001. To be initially placed on the AAIP, the airplane must undergo inspections in accordance with AAIP Events 1, 2, 3, and 4. According to the operator's AAIP inspection schedule, an inspection of the control wheels, columns, pulleys, and cables for condition is required during the Event 4 inspection.