Incident Details
On 31 December 2002 at 1020 UTC, a Boeing 737-230 (registration EI-CNT) arrived at London Stansted Airport following a flight from Londonderry. The aircraft, manufactured in 1980, was powered by two Pratt & Whitney PW JT8D-15 turbofan engines. There were 5 crew members and 127 passengers on board.
After parking at Stand C50, passengers were scheduled to disembark using a conventional set of mobile steps positioned at the aft left-hand door. The steps were pushed against the aircraft fuselage, with the rubber strip contacting the skin a few inches below the door sill. A young woman, among the first passengers to exit, stepped from the cabin onto the top step. As her foot slipped, she collapsed and suffered a badly dislocated knee.
Response and Inspection
Ground handling personnel immediately contacted airport and external emergency services. The passenger was not moved until medical staff arrived and subsequently transported her to Harlow Hospital. The handling company removed the mobile steps from service for inspection. The inspection report stated the steps were in proper working order, with metal treads featuring a raised grid that were clear of grease and dry at the time of the incident. Additionally, the steps had the parking brake applied, stabilisers deployed, and safety guard rails in place.
An officer from the Airport Police, who attended the scene, confirmed the steps were properly positioned next to the aircraft, with the first tread at a reasonable height of 4 to 6 inches below the door sill. However, the officer noted that conditions were cold, wet, and windy, and described the treads as slippery.
Weather Conditions
The flight crew reported the actual weather conditions at the time: north-easterly wind at 5 to 10 knots, scattered cloud at 4,500 feet, no significant weather, and an air temperature of 1°C.
Passenger Account
The injured passenger recalled being among the first to leave the aircraft. As she placed her left foot onto the first tread, it slipped and her knee dislocated upon falling. She noted that this dislocation had occurred to the same knee several times previously. She suggested that a crew announcement before disembarkation regarding the step conditions would have been helpful.
Statistical Context
The UK CAA does not maintain detailed reports of such ground incidents. The AAIB discussed mobile step safety with a major UK airline that has comprehensive air and ground safety programmes. That airline reported three instances of passengers or staff slipping on mobile aircraft steps over a recent 12-month period. These statistics did not indicate slipping on mobile steps as a significant hazard.