43173 passes Bourton on the frosty morning of 28 December 1985 with the 1A20 08:45 Bristol Temple Meads to Paddington service. 43173 was the first HST power car to be withdrawn, when it was extensively damaged in the Southall rail crash on 19 September 1997. It was the lead power car of a Swansea to Paddington train, which collided with an ARC stone train, which was correctly signalled to cross its path. Unfortunately the HST's AWS had been isolated due to an earlier brake problem, and the driver failed to respond to two amber signals, only belatedly applying the brakes when very near the red signal protecting the freight train.