What happened
On February 16, 2011, a Cessna Citation C5/C525 (registration HB-VOV) was performing an IFR positioning flight from Grenchen Airport (LSZG) to Newquay, Cornwall. During the takeoff roll on runway 07, the crew noticed that the aircraft was not accelerating as expected. Despite the sluggish performance, the takeoff was continued.
As the aircraft approached rotation speed, the nose failed to lift. The aircraft continued down the runway, eventually overrunning the pavement and entering the adjacent field. During the excursion, the right main landing gear struck a runway end light, and the aircraft traveled over 100 meters across the grass, crossing a small stream before finally lifting off the ground. The crew subsequently diverted to Zurich Airport for an emergency landing. The aircraft sustained significant structural damage to the nose gear, main gear, and rear wing spars.
The investigation
SUST examined the aircraft's performance data, engine records, and cockpit recordings. The investigation established that the aircraft had been parked with the parking brake set. While the crew had performed taxi checks, the specific check for the parking brake status at the start of the takeoff roll was not required by the existing checklists. Investigators also noted that the aircraft lacked any cockpit warning system to alert the crew if the parking brake remained engaged during the takeoff roll.
Findings
- The primary cause of the accident was the failure to abort the takeoff despite observing reduced acceleration.
- The reduced acceleration was directly caused by the parking brake being engaged during the takeoff roll.
- The lack of an automated warning device to notify the crew of an engaged parking brake contributed to the event.
- The aircraft's takeoff performance was hindered by the mechanical drag of the brake, preventing the aircraft from reaching rotation speed within the available runway length.