What happened
On 16 November 2004, during preparations for a passenger flight at London Heathrow Airport, a Boeing 747-4Q8, registration G-VTOP, was being loaded at Stand 327. After the rear cargo hold loading had been finished, a high lift loader operator lowered the vehicle's platform to access the door locks. Once the locks were addressed, the operator raised the platform back to the level of the hold door sill and entered the cargo hold to verify the position of the stops and locks.
While the operator was inside the hold, a loud crushing sound occurred. Upon returning to the doorway, the operator discovered that the platform had moved upward, striking the aircraft. This impact resulted in a dent near the cargo loading door and a cracked frame. There were no injuries to the 179 passengers or 19 crew members, and no injuries were sustained by the ground staff.
The investigation
An investigation conducted by the airline examined the mechanical operation of the ground handling equipment involved. It was established that the high loader's control switch failed to return to the neutral position after the operator released it. Instead, the switch remained latched in the 'up' position. This malfunction caused the platform to continue rising, albeit at a slower speed than usual, which went unnoticed by the operator while they were inside the hold.
Findings
- The primary cause of the damage was the failure of the high loader control switch to return to neutral.
- The platform continued to ascend after the operator had exited the controls, leading to the collision with the Boeast 747-4Q8 cargo door frame.
- The slow rate of the unintended ascent prevented the operator from detecting the movement before the impact occurred.