Incident
On 10 May 2001 at 1232 UTC, a Douglas (Boeing) MD-83, registration EC-FXI, was completing a holiday charter flight from Palma, Majorca, to Liverpool Airport, UK. The aircraft performed an automatic landing on Runway 27, with the first officer as the pilot flying. Immediately upon touchdown, the right main landing gear (MLG) failed. The aircraft slid along the runway for approximately 1,600 metres before coming to a halt, resting on its right flaps, slats, and wingtip. An emergency evacuation was conducted; there were no injuries or fire.
Aircraft Damage
The failure resulted in major damage to the right wing flaps, slats, and skin, punctures in the fuselage skin, and ingestion damage to the right engine. The right MLG strut cylinder fractured below the attachment trunnions, releasing the wheels and axle assembly into the flaps and wing/fuselage fairing. The lower portion of the failed cylinder remained attached only by the sidestay.
Examination
Inspection of the fracture surface revealed an anomaly on the forward outer surface of the cylinder, identified as a fatigue crack measuring approximately 3.5 mm long and 1.1 mm deep.
Previous Occurrences
The location and size of this crack were similar to one that caused an MLG failure on another MD-83, registration G-DEVR, at Manchester Airport on 27 April 1995. Following that accident, the FAA ordered a mandatory modification to the aircraft's braking system and a one-time non-destructive evaluation (NDE) inspection of the critical area. The AAIB expressed concern that these measures had not prevented a similar accident. A further case of MLG failure due to a similar mechanism occurred to an aircraft of the same type operated by a Chinese operator in April 1997.
Investigation Status
Examination of the fractured component, maintenance records, and the conduct of the flight continued. The AAIB issued Safety Recommendation No. 2001-54, urging the FAA and Boeing Commercial Airplane Group to urgently review the continued airworthiness of the MD-83 MLG strut. Specifically, it called for consideration of repeat inspections and reassessment of the mandated NDE's ability to detect small fatigue cracks given the critical crack size. The Chief Inspector of Air Accidents ordered a Formal Investigation.