Anybody know what is hauling it and what the train weight is?
88010 on 4M27 had 1283 tons behind it today, which is below their 1400 ton max load.
I've long left involvement but it was the case that there was then a document titled 'Freight Trains Load Book' ('FTLB') which listed, as its name suggests, the maximum load by loco class over each section of route.
The traditional system of the loads books still applies (albeit now in the form of an excel spreadsheet). Class 88s working solo are authorised to haul a trailing tonnage of 1400 tons in either direction between Daventry and Coatbridge. The loads book takes into account the characteristics of each line (mainly the gradients) as you would expect, but warns that adverse weather conditions can sometimes reduce the weight a loco is able to pull:
The manual assumes standard train resistance and adhesion parameters. Train resistance can alter significantly due to atmospheric conditions such as headwinds. Adhesion can be significantly reduced by adverse railhead conditions.
In today's case it looks like the issue with 88010 on 4M27 was a loco fault, rather than a problem with adhesion.
Also of interest in relation to this thread is that class 93s were recently tested by DRS on these Daventry - Coatbridge Tesco services, with 93009 working a 4Q45 / 4Q27 diagram in mid-July. 4Q27 was running in the path of the usual 4M27 service, i.e. the one which had problems today. With 9 workings in each direction taking place between the 12th and 22nd July using a class 93, it suggests that serious consideration is being given to using these locos on the services in the future (other tests by DB Cargo and Freightliner using class 93s on this route have been more of a one-off demonstration run).
See the class 93 thread for more info and discussion on this topic - in
post #2494 it was suggested the DRS lease agreement for the 88s ends in 2027, which could be significant. Whether class 93s will take over these Daventry - Coatbridge services for DRS at some point is open to speculation, but after this recent trial (and the earlier decision to move the home base of the class 93s to the DRS depot at Crewe Gresty Bridge) I'm cautiously optimistic. Although based on the class 88s, the 93s are a later development of the design which seems to be a bit more capable, and I think they could be a worthwhile improvement which would hopefully alleviate some of the issues discussed in this thread.
Although I've questioned the suitability of 88s on these services, I think it's fair to point out that the signalling is also inadequate in the event of a train failure, with the 2-track section of the WCML north of Preston sorely in need of bi-directional signalling, as per the comment in
post #148 of this thread. Hopefully this can be done at some stage, although given the cost it would almost certainly have to wait until sections of the existing signalling become life-expired and due for renewal. With bi-directional signalling, a failed train still causes delays, but not the kind of service meltdown we see at the moment.
