An inquiry led by Lord Cullen detailed issues with the signals, following ineffective management. The Cullen Report referred to “how so many apparently good people could produce so little action,” and heard of “a seemingly endemic culture of complacency and inaction”.
Only two weeks before the crash, it had been announced that the Train Protection and Warning System (TPWS) would be adopted across the network. It was a lower cost safety mechanism that could stop most trains within the overlap distance beyond a red signal.
This remains in widespread use. A pair of electronic loops in the track, looking like a grid or electric toaster, automatically cause a train to brake if it approaches a danger signal too fast.
“This was the biggest and most dramatic change,” said Martin Frobisher, Network Rail’s safety and engineering director.
“This interim technology has outperformed all expectations.
“It wasn’t the perfect technology. But the perfect technology would have taken a vast investment and decades to introduce, by re-signalling everything.”
Between 1900 and 1999, passengers died nearly every year in crashes caused by a Signal Passed At Danger (SPAD).
But in the quarter-century since Ladbroke Grove, there has not been a fatality caused by SPAD.
This is despite the number of SPADs remaining stubbornly close to 300 every year, with the Salisbury tunnel crash of 2021 the most serious recent example.