Let us bear in mind that the GW main line at Ladbroke Grove was fitted with Automatic Train Protection (ATP), more sophisticated than TPWS, but one of the operators involved had decided not to fit it to their trains. All this after the earlier serious accident nearby at Southall, again when the line was fitted with ATP, but also the train, it was just the operator had decided not to use it. However did all not move to use it after that warning? Especially as FGW on their High Speed Trains after Southall used to have notices inside their trains confirming that ATP was in use. How unfortunate that the FGW train was given the clear road over the Thames train, rather than the other way round.
There was movement afterwards, following much "discussion", that finally enforced fitment. None of this seemed to recognise that after the (old) GWR installed their ATC system (a pioneer AWS) here in the 1930s, they enforced that all passenger services had to use locomotives fitted to use it, which spread as the system rolled out all across the GWR main lines, and led to loco changing at boundaries of the system if needed, which nobody then whinged on about the additional costs resulting. Some BR wiseacre accountant in the 1970s finally rescinded this, and unfitted London Midland diesels started to run through, whereupon within a year or two there was the fatal collision at Bridgwater where such an unfitted LMR loco ran through signals at danger which were fitted with the GWR system.
