An unusual set of circumstances led to some extended delays around the single line overnight.

Both sleeper services were routed via Melksham and both were running late.   The Up sleeper lost half an hour coming through Cornwall while the Down service was delayed by 50 minutes due to an incident east of Swindon.   The pair usually cross in Somerset.   This morning it was between Trowbridge and Westbury.



However behind the westbound sleeper was a queue of trains at Chippenham waiting for the single line to clear.   A couple of them had been allowed to run early at previous points in their journey.  The closure of the line through Chipping Sodbury for overnight engineering work also added to the pressure.  The second in the queue was just waiting for the one in front to take the single line before it could continue towards Bath Spa.



The up sleeper was delayed on the approach to Bradford Junction for 45 minutes while a pair of trains used the single line.  The message on Journeycheck suggested it had been delayed by a late running train in front.   I suppose it was - by the down sleeper!



In all it took nearly three hours for the congestion to clear as other trains joined the queues at both ends.   The worst delay I have seen was a freight train which approached Chippenham 12 minutes early but was 83 minutes late by the time it got to Trowbridge.

In the middle of the night perhaps it doesn't matter so much - but it shows what a knife-edge capacity along the single line is on at times.

 
Many thanks for documenting that, Bob - a really interesting study. Real Time trains confirms 14 trains through Melksham in the 6 hours between midnight and 6 a.m.  Of those, 11 were signifinatly late.



The "dance" can be done in some places - for example, with St Erth to St Ives where the trains are guaranteed to turn up on time, or in a pattern of lateness if one is late, the next presents late.  That requires some exceptional action, such as the notice at St Erth that tells you that the St Ives train won't usually wait, and at St Ives where it's the same train and it automatically synchronises.  It is - utterly - out of the practical question in Wiltshire where train passing the ends of the single line need to be combed in, and the trains that use the single line need to present exactly at a convenient time irrespective of delays getting there, and then to be able to escape it at the far end.

Multiple solutions options to increase practical, relaible capacity have been mooted.  For more than a very modest further traffic increase, at least one of them and probably more need to be implemented.  And of those multiple solutions, to be implemented, a number of them are not on that single track section from last point at Thingley to the first point at Bradford.

 
One benefit of being laid up with a heavy cold and being kept awake with frequent coughing fits! 

 

Get well soon, BobM ... though I have to say that the cloud of your cold has brought the silver lining of this excellent overnight report!

 

I suspect that the businesses on whose behalf a variety of freight services are run overnight would not agree with that sentiment.

 
On the subject of timekeeping of freight services, I've noticed from RTT that the best timekeeping of all the trains through Cheltenham - both passenger and freight -  appears to be the 'Tesco' trains that run between their distribution centres.  I guess that the SLA (Service Level Agreement) for these trains is particularly tight, and tighter than, for example, mineral trains.