The aircraft landed at Manchester at 23:16 and the commander took control from the first officer during the latter part of the landing roll. As he applied increased pressure to the brakes there was a loud bang and the left wing dropped as the left main landing gear collapsed. The aircraft came quickly to a halt and the commander decided to disembark the passengers via the front passenger entrance door and stairs. The cabin supervisor experienced a problem with the stairs and, after a discussion with the commander, the passengers were evacuated via the front and rear service doors using the escape slides. An orderly evacuation ensued with only minor injuries being sustained; all passengers had left the aircraft by 23:26. PROBABLE CAUSE: “(1) The left MLG outer cylinder failed on the application of bending loads resulting from normal braking due to the presence of a fatigue crack, 5ÿmm long by 1.25 mm deep, located on the front face of the cylinder, close to a change in section, where bending stresses were maximum.; (2) The fatigue origin was associated with surface features produced by the gritblasting used to prepare the steel surface for high current density cadmium plating.; (3) Loads not predicted during the MLG design were encountered early in the aircraft’s life when ‘gear walking’, a MLG foreandaft vibration mode, was encountered. As a result fatigue initiated and propagated through the immediate compressive subsurface layer produced by shotpeening and designed to improve fatigue resistance.”