What happened
On 19 February 1998, during a scheduled public transport operation at London Heathrow Airport, a Boeing 737-59D, registration G-BVKA, experienced an incident while being positioned for departure. As the pushback procedure was nearing completion, the tug driver attempted to maneuver the tug to align the aircraft with the taxiway centerline. During this movement, the tug lost traction, causing the upper portion of the driver's cab to make contact with the right side of the aircraft's radome. There were no injuries to the 37 passengers or 7 crew members on board, though the aircraft sustained damage to the radome.
The investigation
An investigation conducted by the Ramp Training and Safety Manager examined the circumstances surrounding the impact. The driver involved was undergoing training at the time of the event. The aircraft commander, an experienced pilot with 10,000 hours on type, noted that the pushback had appeared normal until the moment of impact and confirmed that both CFM56-3C1 engines were running. The investigation looked into the environmental conditions, noting that the ramp surface was likely greasy following overnight rain after a prolonged dry spell. The investigation also noted a slight dip in the taxiway surface at the point of the incident.
Findings
- The primary cause of the incident was the loss of traction by the tug while attempting to straighten the aircraft.
- The greasy surface conditions, resulting from recent rainfall, contributed to the loss of grip.
- The operation of both aircraft engines and a slight depression in the taxiway surface further complicated the maneuver.
Safety action
Following the event, the Ramp Training and Safety Manager issued a 'Ramp Alert'. This notification was intended to advise tug drivers and headset operators to maintain closer communication with aircraft commanders when operating on slippery ramp surfaces.