What happened
During the takeoff roll on runway 30, a Swearing and Metro SA226-T began to veer toward the right side of the concrete surface. The pilot reported advancing the power levers to approximately 80% torque while holding the brakes with neutral rudder pedals, then releasing the brakes using the nosewheel steering power lever button. While the aircraft initially accelerated near the centerline, it began to drift right at approximately 50 knots. Despite the pilot reengaging the nosewheel steering and applying rudder, the aircraft continued its deviation from the runway.
The pilot initiated an aborted takeoff procedure; however, the aircraft was unable to stop on the concrete surface. The aircraft exited the runway approximately 720 feet from the start of the takeoff roll, striking a runway light. As it moved off the pavement, the nose gear collapsed in soft dirt. There were no injuries reported, but the aircraft sustained substantial damage.
The investigation
An on-site inspection identified tire skid marks approximately 50 feet in length where the aircraft left the runway at an angle of 30 to 35 degrees. The left skid mark was measured nine feet to the right of the runway centerline. While the nosewheel steering system could not be inspected due to impact damage, the inspection of the aircraft revealed no anomalies that could be associated with a pre-impact condition.
Findings
- The Pre-takeoff Checklist requires a Steering and Alignment check to verify the operational status of the nosewheel steering system; the manual specifies that the nosewheel steering should not be used if this check fails.
- According to the Swearingen Metro SA226-T Airplane Flight Manual, if a malfunction occurs in the nosewheel steering mechanism, adequate steering can be maintained through the use of rudder, brakes, and/or differential power.