5at Train

The 5AT Group - Steaming Ahead with Advanced Technology

Enhancing Performance -- Improving Reliability -- Reducing Costs -- Controlling Emissions


David Wardale's complete
5AT Fundamental Design Calculations

are now available in printed format and are available for purchase through this website.
Please go to the "Sales Page"for further information


As noted elsewhere on this website, since the 5AT Project was suspended in 2012, the members of the 5AT team have regrouped under the banner of The Advanced Steam Traction Trust.

The 5AT Project website remains in place to provide information on the concepts and technology on which the 5AT design was based.

"No other product of man's mind has ever exercised such a compelling hold upon the public's imagination as the steam locomotive. No other machine in its day has been a more faithful friend to mankind, nor has contributed more to the growth of industry in this, the land of its birth and indeed throughout the whole world. Those who have lived in the steam age of railways will carry the most nostalgic memories right to the end.."
The words of R F Hanks, Chairman of the Western Area Board of British Railways at a ceremony in Swindon Works on 18th March 1960, marking the end of steam locomotive construction in the UK with the completion and naming of 9F 2-10-0 No 92220 "Evening Star".

The 5AT Project

Mr Hanks' words (above) are as true today as they were in 1960, though the nostalgia and passion that the steam locomotive generates has extended far wider, and for far longer, than he could have imagined. Most preserved steam operated railways in the UK continue to attract record numbers of visitors each year, and 2009 witnessed widespread public interest and enthusiasm when "Tornado", the first main line steam locomotive to be built in the UK since "Evening Star", made its public debut on the nation's railways.

The 5AT Project aimed to go a step further, namely to build the first new steam locomotive incorporating all the proven technical advances that have been developed since 1960 in order to generate the power, speed, range and reliability that may one day be needed to maintain an ongoing presence for steam traction on the main line rail network of the future.

The 5AT Project was suspended in 2012 due to lack of financial support, however the 5AT Group which spawned from it, is now pursuing new goals.

The 5AT Group

The 10 years spent by the 5AT Group in the planning and promotion of the 5AT Project have not been in vain.  Indeed, the group is continuing in the pursuit of its goal of maintaining a future presence for steam traction on main and heritage rail lines, through the application of technical improvements that will increase locomotive performance and reliability, reduce both carbon and spark emissions, and minimize operating and maintenance costs.

The 5AT Group can help locomotive owners or new build groups, whether standard or narrow gauge by making them

  • more efficient,
  • less polluting,
  • cheaper to run and
  • above all, more reliable.

The 5AT Group aims to preserve for future generations the expertise and experience of pioneers of Modern Steam, such André Chapelon, Livio Dante Porta and David Wardale.

This website outlines some of the Modernising Options that the 5AT Group can make available to locomotive owners and builders.  It explains the Principles of Modern Steam and providing examples of what can be achieved (see Modern Steam Miscellany).




5AT Project Legacy

The 5AT Project, proposed by David Wardale in the concluding pages of his seminal book "The Red Devil and Other Tales from the Age of Steam", aimed to build the first new steam locomotive incorporating all the proven technical advances developed since the 1960s, and was aimed at delivering the level of range, power, speed and reliability that will one day be needed to maintain  steam on the 21st Century main line railway.

The 5AT Project failed to attract the £11 million funding that was needed to design and construct the locomotive and its abandonment was publically announced in early 2012.

The Project Feasibility Study, completed in 2010, included a complete set of Fundamental Design Calculations by David Wardale which spell out the design calculations for the development of virtually any new Modern Steam locomotive design.  The calculations can be adapted to “modernise” existing locomotives and recreations of old designs.  The Fundamental Design Calculations, plus the use of 21st Century Design Tools and Techniques are the foundation of the Trust’s capability to offer its services to the heritage railways, mainline steam locomotives and new-build steam projects.

The 5AT Group is made up of a team of engineers and other professionals with complementary skills in steam locomotive technology and 21st Century design tools and techniques.

Features of the 5AT included:

  • Maximum continuous operating speed of 180 km/h (113 mph) to keep up with modern rail traffic; and a maximum design speed of 200 km/h (125 mph);
  • High power to weight ratio: 1890 kW (2535 hp) at the drawbar (indicated power 2380 kW or 3200 hp) at 113 km/h (70 mph) from an 80 tonne locomotive;
  • Optimised adhesion to control slipping;
  • High thermal efficiency (for steam traction) of approximately 14%;
  • Wide route availability - 20 tonne axle load;
  • Simplicity, reliability, easy maintenance and servicing;
  • High capacity tender to provide extended range;
  • Low fuel and water consumption (see note below);
  • Conformance to latest safety regulations;
  • Good crew conditions;
  • Gas-oil fuel (similar to diesel) with an option for a coal fired version.

The 5AT's fuel and water ranges are calculated to be 925 km (570 miles) and 610 km (380 miles) respectively under representative average service conditions, and 552 km (345 miles) and 367 km (230 miles) respectively at maximum drawbar power - i.e. at 1890 kW (2535 hp) and 113 km/h (70 mph). See Operating Range page.