Class 50
English Electric
This is a type which
has had an interesting and varied past, and a popular following. The fleet’s
existence stemmed from the need to speed up services on the non-electrified
Crewe to Glasgow section of the West Coast Main Line. Euston to Crewe (or,
rather, Weaver Junction) became ‘’live’’ by means of 25kV overhead wires on 18th
April 1966, and it was also then possible to reach Liverpool and Manchester by
electric haulage. British Rail reportedly preferred to turn on the electric
current some time before such services commenced, to prevent theft of overhead
wire components, but were apparently informed by the police that such a course
of action may in fact be illegal. The quickest Euston to Glasgow journey after these works was
timed at 6 hours 35 minutes; the section between the capital and Crewe had at
least witnessed a travelling time reduction of a third since the commencement of
the electric timetable. It was not definite that the wires would be perpetuated
north beyond Weaver Junction (where the Liverpool Lime Street line branched
off), at least in the medium term, but there was still a strong desire to speed
up services north of Crewe. The situation arose during the thick of the Brush
Type 4 (Class 47) construction programme, which had gathered momentum in 1962.
Whilst it may have seemed natural to place an additional order for uprated
versions of this locomotive to take on the task, so far the fleet had been
troublesome, and although an engine rebuild and exchange exercise was taking
place, British Rail had initial misgivings over whether the modified 12LDA
powerplants would overcome unreliability issues. In the meantime, English
Electric had been experiencing success with a private venture in the form of DP2
(Diesel Prototype 2), a 16CSVT engine test bed. First deployed in May 1962,
aesthetically it followed in the footsteps of October 1955-launched DP1 ‘’Deltic’’,
although the mechanical constitution was unprecedented. The DP2 found itself
deployed on the East Coast Main Line alongside production-line Deltics, where it
proved popular with locomotive crews. It demonstrated a greater acceleration
than its counterparts, although it was neither as powerful nor as fast as them,
with engine output and a top speed of 2700 HP and 90 MPH respectively. This
compared with the Deltic’s combined twin Napier engine output of 3300 HP, and a
top operating limit of 100 MPH. Reportedly, DP2 used production line Deltic body
shell number 23: originally, 23 Deltics were to be produced, but this order was
cut back by one, after the body shell had been manufactured. Subsequently, the
surplus shell became part of the then new prototype. Since the outset, DP2 had
worn all-over plain green with end square yellow warning panels, the latter
surrounding the four-character head code panel. However, during its only major
overhaul in August 1965, it was made to conform with BR’s main line fleet on the
East Coast, the familiar two-tone green Deltic scheme being applied.
BR was interested in the fundamental DP2 package offered by English Electric
(EE), but the nationalised organisation’s Chief Draftsmen and Mechanical &
Electrical Engineers had plans: changes were afoot. Whilst EE could provide a
locomotive of comparatively simple design – mechanically and electronically – BR
was instead keen to incorporate untried and untested devices, which would later
prove too complicated and too advanced for the machine they were intended for.
The BR Design Panel’s attitude towards locomotive design had also changed, and
locomotive noses – trademarks of EE products – were deemed unfashionable, and
future body shells had to utilise flat fronts. Reportedly, EE was not pleased
with the decision to dispense with the distinctive Deltic exterior, and to add
insult to injury, a sound electrical system was to be compromised by the
insertion of innovations in the form of slow speed control, rheostatic braking,
and a clean air compartment (the latter of which became known for producing the
‘’hoover’’ noise). Contracts were signed between the British Transport
Commission and EE in 1966 for the construction of fifty ‘’Type
four-and-a-halves’’ (as they were affectionately known during production), these
being destined to fill the electrification breach north of Crewe. EE had been
awarded this work partly as a consolation, in light of Brush Traction receiving
the 512-strong Type 4 order; it also gave BR the opportunity to interfere with
the design programme. Further build schemes were also subcontracted to EE, again
because of Brush’s order size. The 1965 to 1966 Class 86 construction was split
between EE (at the Vulcan Foundry) and BREL Doncaster, and the electrical giant
was also awarded the work of assembling the 42-strong Class 73/1 (JB)
Electro-Diesel fleet between 1965 and 1967, in addition to undertaking the Class
31 engine replacement task.
Construction got underway on the new fleet at the Vulcan Foundry in
Newton-le-Willows in February 1967, and the first locomotive was ready for
testing by September of that year. In the meantime, disaster had struck. On 31st
July 1967, DP2 had come to grief whilst working the 12:00 Kings Cross to
Newcastle express (which was usually diagrammed for a Deltic). Near Thirsk, the
formation collided with a derailed cement train - which it was in the process of
overtaking - crushing the left hand-side of DP2 and resulting in the deaths of
six people travelling in the behind carriages. The stricken DP2 was towed back
to the Vulcan Foundry, with a view to being repaired. However, a subsequent
assessment and strip-down of the locomotive revealed structural damage deemed
uneconomical to repair; this decision was made in light of the BR version’s
construction being in full swing. The last production-line BR locomotive was
completed in December 1968.
Brief mention should also be made of the ten ‘’Type-four-and-a-halves’’ which EE
built for ‘’Caminhos de Ferro Portugueses’’ (Portuguese Railways). Constructed
concurrent with the D400 series, the Portuguese outlined that a locomotive akin
to DP2, at least internally, was preferred. Thus, the dubious additions made by
BR were left out of the export machines, but a version of the flat-fronted body
shell design was utilised. Subsequently becoming the 1800 series on the Iberian
Peninsula, the type did share one common electrical weakness with their British
counterparts: that of the generator. The generator was highly susceptible to
‘’flashovers’’ (i.e. unintended electrical discharges) and the resultant would
be a high repair cost to have the armatures rewound.
The fifty locomotives were numbered in the D400 – D449 series, but at this time,
a cash-strapped BR could not afford to buy the fleet outright. A leasing
arrangement had, however, been agreed on, which suited EE: much of this
company’s substantial income was subject to high taxation. Leasing the then new
diesels rather than selling them allowed the company to spread its profits over
time, reducing the amount of its income being lost as tax. The D400 series utilised
the same 16CSVT engine used in the DP2 and reportedly, the locomotive which
later became No. 50023 reused the original engine block of the scrapped
prototype. Unlike the Brush Type 4 fleet (excepting Nos. D1500 to D1519 of the
East Coast Main Line), the D400 series was equipped with Electric Train Heating
(ETH), and had a top operating speed of 105 MPH, despite nowhere being passed for
this speed. Interestingly, only locomotive Nos. D400 and D401 were fitted with
multiple-working jumper boxes on their cab fronts from the outset.
An early view of the type at Crewe in 1969 reveals No. D412 on the right and No. D415 on the left, both wearing the
familiar all-over BR Blue livery. Happily, D415 exists in preservation, currently under its TOPS guise of No. 50015.
David Glasspool Collection
A 1970 view at Crewe reveals D448 on the left and D428 on the right, the latter displaying
its original head code box above the cab windows to good effect. An interesting line-up of
diesels exist behind the D400 series duo, with a two-tone green Class 40 behind, a third
D400 series in all-over BR Blue, and finally, a two-tone green Class 47. David Glasspool Collection
On 27th June 1987, No. 50013 ''Agincourt'' was Exeter-bound at Teignmouth, departing with
a train consisting
of BR Mk 1 carriages. Mike Glasspool
Next: the History Continues >>
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