Wardale’s Summary

Wardales’ Summary of Fundamental Design Calculations


These notes are copied from a letter written by David Wardale to Chris Newman dated 22nd November 2004, notifying the completion of the 5AT Fundamental Design Calculations.

In undertaking this work, I have had an ‘agenda’ (to use a current term) in addition to providing the foundation for the 5AT. That is to show to my own satisfaction that my supposition that steam could have been far better than it was is correct. There is nothing in the 5AT calculations that was not known in the mid 1950’s when the BR Standards were being built, except the oil burner / atomiser data (the valve gear computer programme was also not available then, but the valve gear would have been quite easily produced by manual draughting by people who were experts in that kind of work). However FDC 1.3. shows that the required steam output could be achieved using coal with the GPCS at a level of combustion efficiency that was then quite acceptable, and the GPCS was then current technology, its principles staring engineers in the face. Therefore oil-firing was not a necessity. So it was my contention in “The Red Devil” that something like the 5AT could have been produced in the 1950’s, being far better than contemporary diesels and therefore obviating any changeover from steam, and that the failure to do so was the fault of the steam fraternity and “gave the knife by the handle” (one of Porta’s phrases) to the opposition. I feel the FDC’s have shown this to be true, at least in a purely technical sense (of course they do not allow for the financial restraints under which the old steam engineers may have had to operate, but this itself seems hardly an excuse when untold millions of £’s were made available (and largely squandered by BR) in the ‘modernisation’ plan).

The FDC’s have been made in the ‘old’ way, because that is the way I was educated and the way I know. This is also the way they would have been made in the 1950’s, and are of necessity the way they have to be done to prove my above point. They would have been acceptable in-toto at that time, which was before the present over-regulated and litigious environment appeared, and would have built seamlessly onto existing steam loco design practice. If, therefore, the steam fraternity had not been so short sighted at the time of nationalisation of the railways in the UK in 1948, and a small amount of money had been set aside for a true steam development section, charged with producing designs for the future at the same time as the BR Standards were being produced for the then-present, something like the 5AT could have appeared by the mid 1950’s when the BR Standards were already becoming obsolete, and could have taken over from them in a continuous seamless development of steam traction technology. If it had been done in this way and steam had continued to develop, then its technology would have developed naturally to satisfy today’s standards.  But it has not been so, and the gap which exists between the way things were done in steam times and today’s requirements is a major problem. Thus some of the FDC’s that would have been quite acceptable in steam times are not now. For example FDC.16. “Stability” is probably in advance of whatever was done then (which would have been mostly based on empiricism and experience) but will not satisfy today’s requirements, which require a computer simulation to be developed just for a 4-6-0. This limitation is freely acknowledged, and in such cases whatever has been done provides no more than a base from which a theory acceptable by today’s standards must be developed by those who are knowledgeable enough to do it.