Rail grinder train - SPAD.
 

The Rail Accident Investigation Branch (RAIB) are to investigate an incident which occurred at Sileby Junction in Leicestershire.

On the 5th of May around 05:29 a maintenance train used to re-profile the rails was travelling on the down slow line near Sileby. It passed a red signal by about 350 metres.

Travelling in the other direction was a train of empty coaches and was crossing the down slow line to move from the up fast to the up slow line.

The train of empty coaches passed over the junction less than 10 seconds before the rail grinding train fouled the junction.

https://www.railadvent.co.uk/2021/06...eid=aa4ee9b801

Thanks for that Philip

Ooh, that's naughty. TPWS is supposed to bring an errant train to a stand within the overlap, thus preventing it from reaching the conflict point.

Something's not right here, and RAIB have dropped some clues...

It not unusual to have to cross oncoming traffic when switching lines, I used to experience it on the Midland Main Line - where the Fast (Up & Down) and Slow (Up & Down) lines are paired. The East Coast Main Line has the better arrangement of pairing the Ups (Slow & Fast), and the Downs (Slow & Fast). That way there's no risk of a head-on collision when swapping lines, which is the worst collision you can get. But it's not unusual, and not a danger - provided that TPWS does its job. And it almost always does - except here.
TPWS Grids are usually set at standard positions apart, to suit the braking curves of modern trains, which nowadays have Dynamic brakes which are very sharp.

Whilst Hi Speed passenger trains can pull up very smartly, heavy freight trains, light locos and On-Track Machines can often take further to stop.

These trains are usually restricted to running at a lower speed than the running line's Permissible Speed, eg....no more than 40mph on a 60mph line. This is calculated from the braking curve figures for each train.

But the grids are only a few hundred yards from the signal. The whole purpose of TPWS is to stop a train before it reaches the Conflict point. In some cases, the overlap needs to be correspondingly longer. But sometimes this is not possible - there is just no extra room.

Ah, the golden oldie. Some poor person working long/hard hours? Nothing new there sadly.

Well as usual, we look forward to reading the report. It's good that nobody was injured and we're not reading about a train smash.

Cheers, John.