CME Sat 6th August

I think you need to read your book more carefully ! The 1942 data refers to locomotives listed with a "*" and these are 45735 / 6 which were the first pair to use the Stanier boiler that was subsequently fitted to all Royal Scots from 1943 onwards (except 46170) and the rebuilt Patriots from 1946 until the conversion programme was cancelled. If memory is correct 46170 had the first taper boiler designated as Crewe Type 2 which was trialled and improved to be designated the Crewe 2A boiler - and the one fitted to all rebuilt 4-6-0s after the successful trials with 45735 Comet and 45736 Phoenix.

 

As others have said, TE gives just one measure of a steam loco's power and it is determined only from the driving wheel diameter, boiler pressure, number of cylinders, and their bore and stroke.

It takes no account of grate area, boiler efficiency, efficiencies (or otherwise) of the internal or external streamlining, type and efficiency of valve gear and many other variables, so a loco with a higher TE might have an abysmal ability to produce steam, then use it poorly.

I'd be interested if anyone could shed light on how the big four (or BR, come to that) actually determined the power classification for a given class. Was it the rather inapproprite TE measure, or did actual performance have a part to play?

The GWR are to blame for everyone thinking TE is all that counts...

 

Thanks for the correction. The Combined Volume is good, very good with various locomotive specifications. But it does get confusing, especially in the Jubilee section.

 

Seriously, you really think so.

 

Nice bomb Toni , matches your new car color LOL .

 

I'm surprised you noticed it!