What happened
On 1 January 2006, an Embraer 135, registration LX-LGK, was prepared for departure at London City Airport. Following parking and the insertion of chocks, the flight crew performed pre-start checks. During this period, the parking brake was left in the OFF position, an omission that went unnoticed by both pilots during the before-start checklist. The aircraft's brakes were notably warm at this time, and the brake was intentionally left OFF to facilitate cooling.
As the departure time neared, ground crew arrived to assist with the departure. A Ground Power Unit (GPU) and its associated tractor were positioned approximately one metre in front of the aircraft. The commander signalled for the ground crew to remove the chocks. After the crew removed the rear chocks and used another chock to displace the front ones, the aircraft began to roll forward. The Embraer 135 struck the GPU and tractor, resulting in two small punctures to the aircraft skin. There were no injuries to the 4 crew members or 29 passengers on board.
The investigation
Investigators examined the sequence of events and the communication methods used during the turnaround. It was established that the flight crew and ground personnel were communicating via hand signals rather than headsets. The commander noted that the dark and rainy conditions contributed to his failure to notice the aircraft's movement until the impact occurred. Furthermore, the ground crew had no way to signal the pilot to apply the brakes once the movement began.
Findings
- The parking brake was not engaged prior to the engine start sequence.
- The failure to set the parking brake was the primary cause of the movement.
- Communication between the flight crew and ground staff was limited to hand signals, as no headset was provided.
- Adverse weather conditions, specifically darkness and rain, hindered the pilot's ability to perceive the aircraft's forward motion.
- The proximity of the GPU and tractor to the aircraft's path increased the risk of collision.