British Rail Class 40

The Class 40 originated in BR's 1955 Modernisation Plan, which called for a 2,000 hp main-line diesel to replace Pacific steam on principal British expresses. English Electric proposed a Type 4 design using the 16SVT Mk II engine — a sixteen-cylinder Vee-form turbocharged engine of 2,000 hp, derived from successful EE marine and stationary diesel practice and sharing parts with the 8SVT (Class 20) and the not-yet-built 12CSVT (Class 37). The 16SVT was a slow-revving, robust, and reliable engine.

The 1Co-Co1 wheel arrangement was selected to give a low individual axle load compatible with secondary main-line track of the period (much of the BR network at the time having axle-load restrictions inherited from steam days). The two outer pony axles were unpowered carrying axles, providing weight distribution while concentrating the tractive effort on the six powered axles of the Co-Co bogies. The cost of this wheel arrangement was a long, heavy, and (in retrospect) somewhat under-powered locomotive of 133 t service weight.

The first locomotive, D200, was completed at Vulcan Foundry in March 1958. Production continued at Vulcan and at RSH Newcastle through to 1962, by which time 200 had been built. The class set the pattern for English Electric's subsequent Type 4 designs, although the more powerful and better-balanced Class 50 of 1967 marked a significant evolution.

The Class 40 worked principal British expresses from 1958 through to the early 1960s, replacing Pacific steam on the East Coast, West Coast, and Anglian main lines. The class's pre-eminence was relatively brief: from 1962 the Class 55 Deltic took over the principal ECML expresses, and from the mid-1960s the more powerful and lighter Class 47 progressively displaced the 40 from the heaviest expresses across the system. From the late 1960s the class was relegated to secondary main-line, parcels, and heavy freight work.

Despite the displacement from top-link work, the Class 40 remained popular with crews and enthusiasts for its reliable 16SVT engine, characteristic whistling exhaust, and broad route availability. The class became closely associated with the North-West (Crewe, Edge Hill, Liverpool) where many of the final-batch examples were concentrated, and with summer Saturday holiday extras to North Wales coast resorts.

Withdrawals began in 1976 and accelerated through the early 1980s as more modern Type 5 diesels (Classes 56 and 58 freight, and the Class 87 AC electric on the WCML) took over the work. The last Class 40 in BR service was 40122 (D200), withdrawn in March 1985 after working a Liverpool–Llandudno enthusiasts' farewell special — a fitting end for the pioneer of the class.

Long, heavy, twin-cab 1Co-Co1 diesel-electric, the longest British twin-cab diesel of its era. The distinctive long bonnets fore and aft of the centre engine compartment give the class its characteristic profile. Phase 1 examples had disc-type headcode panels above each cab; later examples had revised flat-front cab profiles with recessed four-character headcode boxes. The outer pony axles (1-axle pony trucks) are visible at each end of the locomotive ahead of the powered Co-Co bogies. The whistling exhaust note when accelerating and the deep slow-revving 16SVT under load are characteristic.

D200 (later 40122), the first of the class, completed at Vulcan Foundry in March 1958 and the first British Type 4 diesel to enter traffic. Worked the very last main-line Class 40 service in March 1985 — a fitting swansong for the pioneer. Preserved by the National Collection at the National Railway Museum, York; has worked main-line specials in preservation.

D212 Aureol (later 40012), named after the Elder Dempster passenger liner. Preserved at the Midland Railway Centre, Butterley.

D213 Andania (later 40013), named after the Cunard liner. Privately preserved.

D306 Atlantic Conveyor (later 40106), named after the MV Atlantic Conveyor sunk in the 1982 Falklands War. Preserved at the East Lancashire Railway and a regular main-line performer in preservation.

D318 (later 40118), preserved.

D335 Apapa (later 40135), named after the Elder Dempster liner. Privately preserved.

D345 East Lancashire Railway (later 40145), the only Class 40 to be named in preservation rather than during BR service. Operating example based at the East Lancashire Railway.

D351 (later 40151), privately preserved.

BR (1958–1985): the class was distributed across the BR network. Major allocations included Stratford and Norwich (Eastern Region Anglian expresses); Camden, Crewe, and Edge Hill (Western Lines and West Coast expresses); Haymarket and Edinburgh (Scottish ECML and WCML expresses); and the principal freight depots (Tinsley, Healey Mills, Bescot). The class hauled the Royal Scot, Mid-Day Scot, Caledonian, Talisman, Heart of Midlothian, the East Anglian, the Scotsman, and many other named expresses through the early 1960s. From the mid-1960s the class was progressively displaced from the principal express work by the Class 47 and Class 55 Deltic and relegated to secondary expresses, parcels, and freight. From the early 1970s the class was concentrated in the North-West (Crewe, Edge Hill), the North-East (Gateshead, Healey Mills), and Scotland (Eastfield).

Withdrawal (1976–1985): withdrawal commenced in 1976 and continued through the late 1970s and early 1980s. The last main-line working in BR service was by 40122 (D200) on a Liverpool–Llandudno enthusiasts' special in March 1985, after which the class was withdrawn.

BR Brunswick green (1958–1968): the class was outshopped in BR Brunswick green with grey lower bodyside, and (from 1962) revised small yellow warning panels at each end. The Brunswick green Class 40 with disc headcode panels is one of the iconic images of British dieselisation.

BR Rail blue (1965–1985): from the mid-1960s the class progressively wore standard BR Rail blue with full yellow ends. This was the dominant Class 40 livery from c. 1970 to the end of BR service in 1985.

Preservation: preserved Class 40s have appeared in BR Brunswick green, BR Rail blue with yellow ends, and various authentic small-yellow-panel intermediate states, all authentic for the class. Several preserved examples have given main-line operating service in preservation, notably 40145 and 40106.