The Ultimate Steam Page

The A1

Inspired by the Herculean efforts of their predecessors, a group was formed in England who wished to build a new steam locomotive from scratch. While many British steamers were preserved, one particularly successful group of 4-6-2's were all scrapped, the "A-1" class designed by Arthur Peppercorn in 1948. This design was chosen as the basis for the new locomotive and the group became known as the A-1 Trust. Construction is now well underway in Darlington on the Tornado, numbered 61063, with a promised completion date of 27 September 2000. See The A1 Steam Locomotive Trust page for more information.

Apparently never one to miss an opportunity, Ing. L. D. Porta developed and submitted an incredibly detailed ~150 page proposal for improvements to the A-1 which would dramatically increase its efficiency and performance while maintaining the "stock" appearance desired by preservationists. His suggestions included modifications to the inside cylinder arrangement, provision of a gas producer combustion system, enlarged combustion chamber, increased boiler pressure, equalizers for the axles (a common feature in many countries but rare in Great Britain), and an advanced "Lemprex" exhaust system. Numerous other detail improvements were included as well, showing that Porta had devoted considerable time to the study of the design of this locomotive. While the A-1 Trust had already incorporated some of his suggestions (all-welded boiler, increased superheat, roller bearings, enlarged steam passages, and improved valves) they were hesitant to make some of the more radical changes to the design. Perhaps one of the other groups in Britain presently planning construction of a full-size replica steamer will be more receptive to his ideas.