SR West Country and Battle of Britain Classes - Design

Design

The detailed design work for the new mixed-traffic locomotives was undertaken at Brighton railway works where they were scheduled to be constructed. The earliest drawings were for a moderately sized 2-6-0 with similarities to the London and North Eastern Railway K4 class, which Bulleid had helped design for the West Highland Line when he was Nigel Gresley's assistant. However, such a design would have been inadequate for the Kent Coast lines, which required a powerful 2-6-2 or 4-6-0 class. It is not clear why the design was subsequently enlarged to become a smaller version of the Merchant Navy class 4-6-2 as the likely traffic requirement did not warrant such lavish provision, but the incorporation of components from that class enabled standardisation during wartime production difficulties.