To the editor, Steam Railway Magazine:

Congratulations on your foresight in publishing David Wardale's two-part article on the subject of his proposed advanced technology Class 5AT 4-6-0 steam locomotive. Whether we like the idea or not, the future for main line steam is only going to be assured if steps are taken to adopt modern technology in something like the shape and form proposed by Mr Wardale.

I find the idea hugely exciting and my enthusiasm has led me to undertake the development of the website for the 5AT project. By default I have become the"contact person" for visitors' feedback on the "5AT" and this provides me with the opportunity to gauge public reaction to the proposed locomotive. Messages of support for the project have already come from all parts of the world including the USA, Argentina, Australia, South Africa, Spain, Holland, Ireland as well as the UK. It is pleasing to record that it is the younger generation who seem most enthusiastic about the idea of "new steam" - largely because they recognise that only through the development of the technology is steam going to survive through their lifetimes or beyond. There has been a much lower response from my own generation of older enthusiasts who will, sooner or later, need to come to terms with the fact that "new steam" is a key element in the long preservation of the technology - and perhaps even its future restoration as a viable source of locomotive power in conditions where it is suited.

I expect there are many "old-steam" enthusiasts who doubt that the technical specifications for the 5AT are practical or that steam can really achieve the performance that Mr Wardale claims for the 5AT. I believe their doubts are unfounded, and I have every confidence that the 5AT will do everything that Mr Wardale says it will. "New steam" is not actually so new as we might imagine, and Mr Wardale has already demonstrated on the Red Devil the level of improvement that can be achieved through relatively minor modifications to an"old steam" design. Ing. Porta has done the same on several other locomotives. The 5AT design will be based on such tried and proven technology, but for the first time it will be packaged in a totally new design, and for that reason we can confidently expect that it will outperform anything that has gone before it.

Steam Railway magazine has already demonstrated how it can influence its readers. By offering its moral support for the 5AT project, the magazine will not only provide sustenance for its own future and for the future enjoyment of its readers, but will give the 5AT the credibility that it is going to need if it is to be taken seriously as a viable proposition by potential funders and by the rail industry within which it is hoped it will operate.

It is this latter point that Mr Wardale's article did not focus on: namely that the 5AT will only become reality if funding is provided by a commercial enterprise which sees value in owning such a machine. However commercial funding will only be made available if it can be convincingly demonstrated that there are adequate benefits (profits) to be returned from building and owning such a machine. It was in recognition of this fact that a Business Plan has been prepared. which specifically explores those commercial opportunities and balances the cost of building and operating the locomotive against the returns that might be expected to be generated from its operation. The difficulty we face will be in gaining the interest of potential investors, and this, I believe, is where Steam Railway and its reader can best assist.

The Business Plan for the project is currently being revised, and as soon as the revisions are completed it can be made available to interested parties via the website. I urge anyone who has any interest in the future of steam to check out the 5AT website (www.5AT.co.uk) and to contact me with their thoughts and comments about it, and especially with ideas about how to gain the interest of organisations that might consider funding the project. This is probably the most exciting opportunity that has arisen in the post-steam era and it deserves the support of anyone who cares about the future of the technology.

The "5AT Group" is not yet a formal organisation, and perhaps it may never need to become one. I see the role of the group as that of a mid-wife whose functions are to assist in the birth of the beast, and to find an adoptive parent willing to take over its development and operation as a commercial undertaking. No doubt there will be ongoing roles for any members of the group who care to find one, but at this stage, I am looking no further than finding the finance to move the project from an idea in David Wardale's mind into the world of reality. I ask that Steam Railway and its readers adopt the role of god-parents to the 5AT, giving it their blessing and moral support - and in so doing, helping us mid-wives to find a suitable parent to take over its future welfare.

Chris Newman,
China

I have been most interested to read about Mr Wardale's proposed 4-6-0, and a fine looking machine it is too, with perhaps the exception of the "Manorbier Castle" smokebox front! I completely endorse his analysis that steam as we know it may indeed become unviable with regard to main line operation. So it is encouraging that someone has come up with a new and contemporary proposal as opposed to merely building a replica of a machine that has gone before.

However, I cannot help but have misgivings that it is not revolutionary enough. It is probably fair to say that everything necessary for the steam locomotive to compete more effectively against its more "fashionable" contemporaries has already been invented. However, so far this technology has neither been developed far enough, nor has it all been put together on one machine. The nearest we have seen are the Chapelon 4-8-4, No. 242 A1, the B.R. Pacific No. 71000, the Porta 2-10-2s and Mr Wardale's famous "Red Devil".

The steam locomotive deserves an opportunity to demonstrate its full potential. Any new design of engine has to be the best possible, without fear of introducing new features and pushed ahead with a determination to sort out the problems. Looking at the drawing and specification of the proposed 5AT, I cannot help but worry that Mr Wardale has been afflicted a little by the steam locomotive designer's traditional conservatism. "We will build what we built before without pushing the boundaries out too far, because we want to know that the product will work". Historically, this has meant that there was comparatively little in the way of pure research and the diesel manufacturers wound up laughing all the way to the bank.

Mr Wardale is rightly concerned about hammer blow on a 2 cylinder machine. Astonishing therefore that the engine has been drawn with ordinary Walschaerts valve gear, which will contribute considerably to the reciprocating masses. Surely a more sensible alternative would be to use British Caprotti valve gear, which has no reciprocating mass at all, and gave good results , appropriately on a batch of B.R. Standard Class 5s. The recent experiences and developments with No. 71000 would also be of great value. Probably the strongest argument for rotary cam valve gear on such an experimental machine is that in order to change completely the characteristics of the valve events, all you have to do is insert a different set of cams.

Certainly with regard to valve gear, Chapelon himself was very clear. "Poppet valves are necessary...On locomotives with very high superheat to avoid the necessity for lubrication of admission ports of piston valves and thereby protect the oil from cracking effects and retain its........value as a lubricant. For this reason it is simpler to lubricate a poppet valve locomotive...." He also outlined the problems with inertia and the amount of space taken up by modern piston valves. "...the weight of a double beat poppet valve of the type now used is infinitely less, for a given cross section of steam passage, than that of a piston valve even when the latter is of the lightest type in welded plate." Chapelon pointed out that in order to achieve the same valve opening as a piston valve with a travel of 200mm (8 inches) , a poppet valve only had to be lifted off its seat by a mere 30mm (1 1/4 inches approx), with a corresponding reduction in inertia forces.

The other astonishing feature is the omission of compound expansion. Because of its more even torque, the compound engine is less susceptible to slipping than a simple, an important feature for operating on today's railway. Indeed since 1971 when the "Steam Ban" ended, there have been a number of incidents where steam locomotives have embarrassingly slipped to a stand. It is also reputedly a better balanced machine and therefore kinder to the permanent way.

The compound engine is also more efficient. Mr Wardale makes the case for simple expansion being just as effective but historically, it is the compound that has always led the way to greater thermal efficiency, leaving the simple expansion machine to catch up. Of course, it would have to be steam jacketed, with superheated steam. This would improve the poor starting performance which Mr Wardale himself has identified this as one of the key problems relating to steam traction. Of course it would be more expensive and more complex but do we not live by expensive technology, the complexity of which is far in excess of a compound expansion locomotive.

I hope Mr Wardale has not been discouraged and disheartened by his experiences in China and with the ACE project, which he wrote about in his book "The Red Devil". It is probably fair to say that those who take an interest in advanced/advancing steam are more likely to favour and support a machine with the features outlined above. A more radical solution is surely the only solution and Mr Wardale should be encouraged wholeheartedly to think in this way. If steam traction could be brought to the same level of effectiveness and economy as its more fashionable counterparts, could some TOC not be tempted to use it to enhance its prestige on some services? As L.D. Porta has said and oft been quoted recently "a) You continue to use diesel or.....b)Use what we offer. Buy it or not."

When the railways dispensed with steam, they threw away what had made them special. Steam had given them style, glamour and mystique. What replaced it has made valiant efforts to be anything more than mundane and prosaic but has not really succeeded in capturing the public imagination. Given that we now live in a society where lifestyle is everything (as witness the ever more bizarre television commercials for motor cars), surely the railways were extremely unwise. Who is to say that if steam could be made competitive, the railways would not like it back, at least just a little!

Previous airings of Mr Wardale's 4-6-0 in the railway press have met with a stony silence in response. With his book now on its third (I think!) printing, I cannot believe that there are not people who hold strong views. Please can you print some letters about this machine and promote debate?

Yours sincerely,
Angus Eickhoff