The excellent railcar.co.uk website hosts copies of BR's London Midland Region Lightweight Trains Committee minutes. Reading these in sequence, one can get an insight into the evolution of the Class 124 Trans-Pennine multiple units. Interestingly, they weren't originally planned for the Liverpool to Hull service. There were three routes under consideration early in the life of the project:
The Liverpool & Manchester to Birmingham services were slightly less progressed than the Liverpool-Leeds-Bradford scheme, with an end-to-end journey time of 1 hour 40 minutes expected; it isn't clear if this was the expected time from Liverpool or Manchester. In either case, it was hoped to extend service through to Coventry. Four units in service were expected to be required, presumably with overheads for maintenance and reliefs, but as these would primarily serve business traffic there would be a reduced demand on Saturdays. It was hoped that this would allow surplus units to relieve the Liverpool-Leeds-Bradford route. As it happened, the scheme was deferred given plans to electrify the lines in question, and seems never to have resurfaced.
The Western Region's service from Birmingham to Swansea isn't as well documented, presumably since the minutes are for the London Midland Region. Presumably this would have run along the main line via Stratford and Gloucester, which actually saw operations with the first six Swindon 79xxx-series units. These units may well have fulfilled this requirement for the Western Region.
The Eastern Region thought they might be able to employ similar units on Kings' Cross to Cambridge, but felt that it might be uneconomic compared to standard two-car DMUs, and in any case was anticipating extension of the Great Northern electrification to cover the route. Their response seems to have been fairly lukewarm.
The North Eastern Region came into the project fairly late, and was interested in dieselising the existing locomotive-hauled service from Liverpool to Hull over the LNWR route. This was the only one of the proposed schemes, possibly excepting Birmingham-Swansea, to enter service. Ironically, despite the units being an LMR plan, this scheme was proposed to the British Transport Commission by the NER who ultimately operated it.
WR and LMR units needed different designs of buffet car, with surprising amounts of time spent developing these - the minutes discuss buffet cars and power trains, but almost no mention is made of the remainder of the passenger accomodation! Destination indicators were initially to be fitted, with a front indicator showing the final terminus and traditional side mounted destination boards. Neither of these seem to have made it into service, though I imagine the headcode box replaced the front destination indicator.
Technically, it was expected that the trains would be a clear move away from legacy rolling stock, with air brakes and electric heating, and capable of running at 85mph - sightlines and signalling were to be checked for this speed. The units actually built only ran at 70mph, and seem overpowered for this speed even considering gradients. I can't help wondering if the 85mph speed was still being hoped for quite late, but never materialised.
Early powertrain work was done on the basis of a 450hp Paxman engine - which must have been the ZH - in an under-floor mounting. It isn't clear what form of transmission was planned, but a demonstrator was built that clocked up in excess of 22,000 miles. An alternative scheme was for a 'mobile power house', presumably diesel-electric, with above-floor engines. The corridor width past the engine would not be acceptable for passenger access, though, so such a configuration would need to have end power cars similar to the later Blue Pullman.
From the start, though, the London Midland region was clear that it wanted to have clear views to the front and rear, meaning no end gangways as were provided on contemporary Western Region and Scottish Region Inter-City multiple units. This would suggest that the 'mobile power house' was unlikely to have found favour. The choice of engine stalled design of the trains for nearly a year between mid-late 1957 and May 1958, before pairs of 238hp Rolls-Royce engines were settled on, despite the Paxman engine being satisfactory.
With operations planned to start in June 1960, all units needed to be delivered by May 1960, and an order placed by January of that year. Approval came from the British Transport Commission by the end of April 1959, leading to the units entering service (six months late) in 1961.
- Liverpool to Leeds via Manchester Victoria and the Diggle route, reversing at Bradford
- Liverpool & Manchester to Birmingham
- Birmingham to Swansea, intended to be a Western Region route
The Liverpool & Manchester to Birmingham services were slightly less progressed than the Liverpool-Leeds-Bradford scheme, with an end-to-end journey time of 1 hour 40 minutes expected; it isn't clear if this was the expected time from Liverpool or Manchester. In either case, it was hoped to extend service through to Coventry. Four units in service were expected to be required, presumably with overheads for maintenance and reliefs, but as these would primarily serve business traffic there would be a reduced demand on Saturdays. It was hoped that this would allow surplus units to relieve the Liverpool-Leeds-Bradford route. As it happened, the scheme was deferred given plans to electrify the lines in question, and seems never to have resurfaced.
The Western Region's service from Birmingham to Swansea isn't as well documented, presumably since the minutes are for the London Midland Region. Presumably this would have run along the main line via Stratford and Gloucester, which actually saw operations with the first six Swindon 79xxx-series units. These units may well have fulfilled this requirement for the Western Region.
The Eastern Region thought they might be able to employ similar units on Kings' Cross to Cambridge, but felt that it might be uneconomic compared to standard two-car DMUs, and in any case was anticipating extension of the Great Northern electrification to cover the route. Their response seems to have been fairly lukewarm.
The North Eastern Region came into the project fairly late, and was interested in dieselising the existing locomotive-hauled service from Liverpool to Hull over the LNWR route. This was the only one of the proposed schemes, possibly excepting Birmingham-Swansea, to enter service. Ironically, despite the units being an LMR plan, this scheme was proposed to the British Transport Commission by the NER who ultimately operated it.
WR and LMR units needed different designs of buffet car, with surprising amounts of time spent developing these - the minutes discuss buffet cars and power trains, but almost no mention is made of the remainder of the passenger accomodation! Destination indicators were initially to be fitted, with a front indicator showing the final terminus and traditional side mounted destination boards. Neither of these seem to have made it into service, though I imagine the headcode box replaced the front destination indicator.
Technically, it was expected that the trains would be a clear move away from legacy rolling stock, with air brakes and electric heating, and capable of running at 85mph - sightlines and signalling were to be checked for this speed. The units actually built only ran at 70mph, and seem overpowered for this speed even considering gradients. I can't help wondering if the 85mph speed was still being hoped for quite late, but never materialised.
Early powertrain work was done on the basis of a 450hp Paxman engine - which must have been the ZH - in an under-floor mounting. It isn't clear what form of transmission was planned, but a demonstrator was built that clocked up in excess of 22,000 miles. An alternative scheme was for a 'mobile power house', presumably diesel-electric, with above-floor engines. The corridor width past the engine would not be acceptable for passenger access, though, so such a configuration would need to have end power cars similar to the later Blue Pullman.
From the start, though, the London Midland region was clear that it wanted to have clear views to the front and rear, meaning no end gangways as were provided on contemporary Western Region and Scottish Region Inter-City multiple units. This would suggest that the 'mobile power house' was unlikely to have found favour. The choice of engine stalled design of the trains for nearly a year between mid-late 1957 and May 1958, before pairs of 238hp Rolls-Royce engines were settled on, despite the Paxman engine being satisfactory.
With operations planned to start in June 1960, all units needed to be delivered by May 1960, and an order placed by January of that year. Approval came from the British Transport Commission by the end of April 1959, leading to the units entering service (six months late) in 1961.