What happened
On 22 June 2006, a Dornier 328 Series 100, registration TF-CSB, was performing a passenger flight that landed normally at Aberdeen Airport. Following the touchdown, the co-pilot, acting as the pilot flying, encountered difficulty releasing the latches on the power levers. This prevented the levers from being moved rearwards from the flight idle position into the beta control range, a necessary step for aircraft deceleration.
After two failed attempts by the co-pilot, the commander took control of the aircraft. While applying aggressive braking, the commander made four additional attempts to release the latches, all of which were unsuccessful. As the aircraft continued along the runway, the commander steered the plane to avoid runway lights and antenna installations. During the excursion, the commander also attempted to move the condition levers to shut down the engines. The aircraft eventually overran the end of Runway 3 and travelled approximately 350 metres across rough grass before coming to a stop. There were no injuries to the 3 crew members or 16 passengers, and the aircraft sustained no damage.
The investigation
The AAIB investigation focused on the mechanical failure of the power lever gate and latches. The investigation noted that the design of the condition levers and the uneven terrain made the engine shutdown attempt difficult. The investigation also referenced a 1999 incident involving a similar aircraft in Genoa, where a failure to move power levers into the reverse thrust position resulted in a fatal runway overrun.
Findings
- The primary cause of the overrun was the inability to move the power levers from flight idle to the beta control range.
- The crew was unable to engage the reverse thrust necessary for effective deceleration.
- The aircraft's movement over uneven ground complicated the crew's efforts to manage the engine condition levers.
Safety action
Following the investigation, Safety Recommendation 2006-104 was issued to Avcraft Aerospace GmbH i.I. The recommendation advises the manufacturer to provide all Dornier 328 operators with detailed emergency procedures and adequate training to manage situations where the power levers cannot be moved from the flight idle position after landing.