BR Double blastpipes

A stated aim of the BR Standard designs was to maintain rather than improve on the performances of existing pre-nationalisation classes and not necessarily to improve on their fuel consumption either. The Britannias were intended to compare with the Class 7 types: Royal Scots, V2s, Castles and not the big Pacifics. Fitting a double chimney - or more likely a Kylchap - might allow them to do this but then leave a hole in the Class 7 provision. And what would be the implications for additional wear and tear and, yes, increased maintenance costs?

The professional engineer considers the design package from many viewpoints of which performance output is but one. Unfortunately, the enthusiast sees that performance output as the be-all and end-all and the other criteria should be sacrificed to achieve the maximum. Possibly the biggest example of this was their disappointment that 9Fs were not allowed to work passenger trains at 90 mph irrespective of the damage they would inflict on themselves, track and other infrastructure while so doing.

 

Totally agree, I wasn't advocating for a dc Brit simply noting that if capability was improved that would take it into a notionally higher power category.
Or more in hand for occasional extremis.