Mk 3 DVTs

[DK123GWR]

According to Wikipedia: "British Rail Engineering Limited's Derby Litchurch Lane Works built 52 Mark 3 DVTs to operate with Mark 2 and Mark 3 sets in push-pull mode with 86, 87 and 90 class locomotives on InterCity West Coast Main Line services from London Euston to Wolverhampton, Manchester, Liverpool and Glasgow allowing the retirement of the 81, 82, 83, 84 and 85 class locomotives"

 

Did introducing DVTs allow this, and if so how? If it were the case that two locos were needed on each train (one at each end) before DVTs then I would understand, as this would effectively double the number of locos available. However, further reading suggests that it was standard practise for a loco to run around its train at each end of the line. Please forgive me if I'm being dim and failing to read the article properly - its getting a little late here so I'm not at my sharpest. Thanks in advance for any information that you may be able to share.

[keefer]

I'd suggest the 84s were long gone anyway.

If the DVTs allowed the withdrawal of anything it would be the four cl. 82 & 83 locos that were retained for carriage pilot duties on the MK2 a/c and mk3 rakes. IIRC these classes were stored/withdrawn but the 4 locos were reinstated specifically to shunt the stock.

I don't think the 81 & 85 were used on the rakes/services that would eventually gain DVTs - they would've been on secondary/parcels trains?

Edited July 23, 2020 by keefer

[Bomag]

At the terminal stations on the WCML and GEML most of the crossovers had been removed, or were difficult to use, so when a train arrived the loco at the buffers was detached and a new one put on the other end for the next service. Once the train, left the original loco was moved onto the end of the next train to arrive to take it out.  Given the number of closely spaced departures from Euston I think they needed 6 locos for every 5 departures. They also had the handful of 82 and 83s to take stock back to Brent Sidings / Stonebridge Park to avoid wasting a 86 or 87. By having the DVT you have the same loco on the other end all diagram and save the extra loco and the 82/83s. It also sped up the turn around times. By releasing effectively  27 Class 86 and 87 diagrams by the DVTs (and DBSO on GEML) there were enough spare locos to cover the class 81 (mostly wd 87-89and some class 85 diagrams on secondary passenger, parcel and some freight services (class 84 had long gone) .

 

The Class 90s were lateish - only the first ones went to Intercity which released several 86/4 for use by parcels and freight-liner.  This, along with the later class 90 going directly to parcel and freight operates  finally saw the end of the class 85 (msotly wd 1990-91). While I don't think that class 81 were still regularly used on class 1 trains by the mid 1980's I did have some 85 haulage.

[DY444]

Run rounds did occur at places like New St and Oxley (for the Wolverhampton terminators) but the normal practice at Euston, Manchester, Liverpool and Glasgow was to provide a fresh engine. 

 

My overriding memories of Euston in the 1970s and early 1980s are the lines of electric locomotives stabled in the inter-platform sidings on the west side of the station and the almost constant coming and going of light engines.