Notes on FDC 1

Notes on the “General Calculations” (FDC 1) as published on this Website


he General Calculations for the 5AT are available on this site in PDF format.  It is intended for the moment only to present the General Calculations for the 5AT locomotive on this website, however notes are provided on some of the other FDCs.

These “General Calculations” form the basis of the Fundamental Design Calculations for the locomotive which were completed by David Wardale in 2005. All calculations for the FDCs are presented in tabular format similar to that used for the General Calculations, and follow a logical stepped sequential methodology formulated by Ing Livio Dante Porta over the period of his career.

The General Calculations demonstrate the elegance of Porta’s design methods and the relative ease with which they may be followed by anyone with a grasp of engineering principles. The calculation methodology aims to provide not only for the logical and comprehensive design of the 5AT, but for the design of virtually any steam locomotive of any size or arrangement.  [Note: Since the 5AT is a simple locomotive, the FDC’s would have to be modified and expanded for the design of a compound locomotive.]

The General Calculations are broken down into five sections as follows:

It will be noted that there are two distinct and separate version of FDC 1.3. These illustrate the iterative nature of the design process adopted by Wardale, where he began his calculations with FDC 1.3 (the lastest amendment being FDC 1.3b), and after completion of all 18 FDCs he revised his original assumptions by substituting derived values to create the final set of calculations under FDC 1.3F.

Wardale begins FDC 1.3F with a note saying:

“These calculations are the original calculations [1.3.] with data from the FDC’s substituted for the original figures (given here in brackets) where it is different. Any original material no longer valid is struck through and additional material is underlined (for ease of reference to FDC 1.3).”


Get Acrobat ReaderThese calculations are presented in Adobe Acrobat PDF format. If you don’t have Acrobat Reader software, please click the Acrobat icon (at right) to download it free directly from Adobe’s website.