GWR four-cylinder arrangement?

So, in other words, when the economies of scale shifted from superb bespoke one-offs to less brilliant but highly commoditised one-offs

 

Y6s, As and Js bespoke one-offs? The N&W had hundreds of Class Y!

A 44
J 14
Y1 5
Y2 31
Y3 80
Y4 10
Y5 20
Y6 81

All the class Ys, except the Y1s and Y2s, lasted until the late fifties.

 

Yes, one-offs. In comparison to what was coming out of GE and GM, the N&W steam types were relatively few in number, and lacked the economies of scale that the diesels provided.

Taking your list of Y6, A and J classes, that was a total of 138 locomotives in the three classes, rising to 218 if you include all flavours of Y. That compares against nearly 4000 F7s, and a similar number of GP9s.

I'm with @Jamessquared - railways are economic enterprises, and traction choices are about the economic ability of that enterprise to do the work being asked of it. To me, the superiority of the diesels is not on a Top Trumps set of criteria, but the fact that the railroads could justify replacing steam so quickly and brutally - efficiencies that went much deeper than those criteria allow. The economist in me notes the advantage of low cost coal, but that saving also had a cost in what could not be sold to the wider market.

I don't dispute that these were phenomenal machines - just the contention that their era could have lasted much longer. Just as rail replaced the stagecoach and canal, their day was done not though their fault but because the world had changed.

 

AFAIK the N&W was unusual amongst US Railroads in building its own loco's.

As in the UK it wasnt just the cost of buying and running loco's it was the finance deals that the diesel builders could offer that had an influence

 

The N&W had 191 Ys until 1957; you have a strange definition of one-offs. Where did I state that railways weren't economic enterprises? My only gripe is that the work of Chapelon is constantly misrepresented by those who should know better.

 

Some early Ys were built by Alco and Baldwin.

 

I’ve read about those trials and for a steam enthusiast it’s a great result but elsewhere the 1500hp diesel had already won.

 

It was a design unique to the N&W, with a correspondingly limited supply chain. The diesels from GM, EMD and Alco were mass produced and widely available - as were their parts.

You may also want to check your numbers more carefully - I note that you moved from classes Y6 (81 built), A (43 built) and J (14 built) to "Ys" (where Wiki lists 81 Y6 and 80 Y3).

 

Another thing was crew costs. To get a heavy coal drag over Blue Ridge would involve a Y piloting an A and a Y banking. That’s three crews. Lash up a load of diesels and you only need one crew. The N&W articulated machines were superb and proved they could match or exceed the diesels of the day but even if spares etc would have remained available, they would have still succumbed to diesels eventually, especially when the latter became available in ever more powerful versions.

 

The numbers I gave above came from Wikipedia. Classes Y3 and upwards were still in use until at least 1957.

https://en.wikipedia.org/wiki/List_of_Norfolk_and_Western_Railway_locomotives

 

I think you will find that the As were rarely, if ever, used on coal drags. They were designed for fast freight and passenger work. They were less suited to coal dragging than the Ys.

 

Thanks - I was going by the class by class pages, which excluded some of the varieties of Y.

 

It's an interesting report on the Class 85, I'm trying to figure out if the effect would make it better or worse than steam, at starting a train under adverse conditions!
There is also the effect that there would be weight transfer from the leading axles to those further back. Having said that I remember reading that the 1500V DC EM1's on the Woodhead line had an arrangement where the bogies were linked together to reduce weight transfer. I can't remember the details but it's possible that all electrics may have been designed that way.