Duke said:In reply to NickD :
It is astounding how much technology progressed between 1850 and 1920 without changing the fundamentals.
They were definitely a case of "Evolution over Revolution." There is a pretty strong argument made that steam locomotive development never really reached anywhere near what they were capable of and railroads gave up on steam far too soon. After the lessons learned in the '30s with roller bearings, and Lima "Superpower" configurations, development just stagnated and manufacturers got complacent. They gave up on development of steam, they gave up on marketing and advertisement, just resorting to smear campaigns against EMD's FT diesels, and then as soon as the FT got a foothold in the market, they jumped ship. And studies show that the cost-per-mile between steam locomotives and diesel locomotives was much, much closer than anyone was led to believe, and that steam offered more horsepower-per-dollar than early diesels. And replacing entire fleets of perfectly good locomotives for brand-new engines ate into a large part of that cost advantage. The biggest problem was just one of perception: steam was outdated
Pennsylvania, a late adopter of diesels, arguably put the most development into the steam locomotive and got fairly close on unlocking what they could do. Their big T-1s were fairly easy to keep up to pressure, made immense power and were capable of insane speeds, and were very responsive to throttling (which is what gave them the reputation of suffering from traction troubles, engineers used to conventional locomotives would made big throttle adjustments, whereas the T-1 need much finer adjustments). Same with their insane Q1 and Q2 duplexes.
Delaware & Hudson was onto something as well, with their series of multi-stage expansion, extreme high pressure locomotives, but enver quite got them scienced-out. Again, the diesel locomotive got waved in front of them and they dove on it.
Steam turbines, though, like the PRR S2 or the C&O M-1, or the N&W "Jawn Henry" were never the answer. Too fragile, too slow to accelerate and only efficient in a narrow operating speed.
Ross Rowland's ACE3000 program in the '80s was onto something, but fell apart from railroads pulling their funding and internal politics.
