The London, Midland and Scottish Railway and British Railways Class 4 2-6-4T was a family of classes of steam locomotives. A grand total of 800 engines were built to five separate designs by four different mechanical engineers, over a period of 29 years. Each new design was a development of the previous one. The LMS gave the whole group the power classification 4P, under BR 4MT. They are therefore grouped as follows:
LMS Nos BR Nos Design Designer Built Built by LMS Built by BR Total built 2300–2424 42300–42424 Fowler Henry Fowler 1927–1934 125 0 125 2500–2536 42500–42536 Stanier, 3 cylinder William Stanier 1934 37 0 37 2425–2494, 2537–2672 42425–42494, 42537–42672 Stanier, 2 cylinder William Stanier 1935–1943 206 0 206 2187–2299, 2673–2699 42050–42299, 42673–42699 Fairburn Charles Fairburn 1945–1951 130 147 277 — 80000–80154 BR Standard Robert Riddles 1951–1956 0 155 155 Total 1927–1956 498 302 800
Withdrawal
All engines were withdrawn from stock between 1959 and 1967, summarised as follows:
+Locomotives withdrawn by year Year Fowler Stanier,3-cylinder Stanier,2-cylinderFairburn BRStandard Total 1959 5 0 0 0 0 5 1960 11 1 2 0 0 14 1961 22 7 17 3 0 49 1962 37 29 43 43 1 153 1963 16 0 29 30 0 75 1964 20 0 51 57 31 159 1965 12 0 38 54 44 148 1966 2 0 11 48 54 115 1967 0 0 15 42 25 82Total 125 37 206 277 155 800 +Locomotives in service at year end Year Fowler Stanier,3-cylinder Stanier,2-cylinder Fairburn BRStandard Total 1958 125 37 206 277 155 800 1959 120 37 206 277 155 795 1960 109 36 204 277 155 781 1961 87 29 187 274 155 732 1962 50 0 144 231 154 579 1963 34 0 115 201 154 504 1964 14 0 64 144 123 345 1965 2 0 26 90 79 197 1966 0 0 15 42 25 82 1967 0 0 0 0 0 0
Technical comparison
For technical purposes, it is worth splitting the Fairburn tanks into two subclasses; early (42050–42146) and late (42147–42699) as their weights differ slightly.
Attribute Fowler Stanier, 3 cylinder Stanier, 2 cylinder Fairburn (early)Derby Lots 177, 185, 186, and 196: locomotives 42147–42699, built 1945–1949 Fairburn (late)Derby Lots 202, 210, and all Brighton-built locomotives: numbers 42050–42146, built 1948–1951 BR StandardLeading wheel diameter Driving wheel diameter Trailing wheel diameter Wheelbase Length Weight Axleload Coal capacity Water capacity Boiler G8AS 4C ABR5Boiler pressure Firegrate area Heating surface: Tubes Heating surface: Firebox Superheater area 266 sq ft / 246 sq ft 160 sq ft/154 sq ft Cylinders 2 outside 3 (1 inside, 2 outside) 2 outsideCylinder size Tractive effort
See also NCC Class WT
References