Model, plastic, 5AT Locomotive, made by William Powell for the 5AT Group, circa 2005. The 5AT was an advanced and modernised steam locomotive based on the BR Standard Class 5. The improvements were the work of locomotive engineer David Wardale, based on the principles of L.D. Porta. The intention was to produce a modern locomotive with improved performance, efficiency, reliability and economy. The 5AT Group formed with the aim of constructing a demonstration loco, but this aim was not realised and the Group folded in 2012, the core of its members forming the Advanced Steam Traction Trust to continue Wardale's work and to apply his calculations to existing or new build locomotives. The Trust produced Wardale's Fundamental Design Calculations for the 5AT in 2015.

This was the only physical model made of the 5AT It is an outline demonstration model only, with no working components. The model is currently in a perspex case.