Edit post

Edit your reply below.

Post Body
Enter your post below.
GP40-2 says that the N&W Y-6b was a dog above 30 MPH . . . Sorry, forty, but the Y-6b's horsepower curve didn't drop off THAT rapidly. But the N&W didn't design the Y-6b (and the Y-6b was just the last class built; the Y-5 and Y-6 and Y-6a classes were just as potent as the Y-6b, incorporating all the newer features as they were developed) to produce high speed horsepower. They had the Class A 2-6-6-4 for those applications. But if a railroad had a topography like N&W's, with the grades and sharp curves N&W had, the Y-6 was the answer. The Y-6 produced DBHP equivalent to the Big Boy and Allegheny at 25 MPH (both those went on to produce more DBHP at higher speeds, of course), but for N&W's grades and curves it was perfect. The compounding that everyone else, and you, disdain meant that this locomotive could do what it did with a boiler the size of a big 4-8-4. Now, my question is - that if compounding could work so well for N&W (don't forget that N&W vied to be at the top of the statistical heap as far as gross ton miles per train hour, and gross income carried over to net - with grades and curvature against loaded coal traffic far worse than C&O's) why would some form of compound not have worked as well for C&O and, of course UP? I'm talking about an engine with maybe 63" instead of the Y-6's 58" drivers . . . On the subject of front end hunting - this needn't have been a problem unless you were going to operate the engine for long distances at speeds in excess of, say, 70 MPH. It wasn't a problem for the N&W 2-6-6-4, and its designers took heart from the high-speed success of the Seaboard 2-6-6-4, which appeared in 1935 and quickly proved itself capable of 60+MPH operation. But here's another comparison, recently in print, that makes the N&W/C&O/UP deal more telling: C&O 2-6-6-6 had 67% of its weight on drivers. Big Boy had 71% of its weight on drivers. N&W Y-6 had 89.7% of its weight on drivers. EMD F-unit had 100.0% of its weight on drivers. This means that the Allegheny's vaunted 6-wheel trailing truck that made it possible to have almost 7500DBHP at 40+MPH, and Big Boy's 4-wheel leading and trailing trucks that helped make it capable of 80MPH speeds, and made it so pretty, were, in mountain service, a liability. Dead weight that had to be dragged up the hill every trip. So history tells us that if you want super horsepower, or super speed, go with the C&O and UP engines. If you want to simply make money, maybe follow N&W's lead. Too bad more didn't. Those old dog Y-6s helped N&W pay out almost two billion dollars in common stock dividends over the 86 years of its existence, they and their predecessor Ys were there for 43 years of it. Old Timer
Tags (Optional)
Tags are keywords that get attached to your post. They are used to categorize your submission and make it easier to search for. To add tags to your post type a tag into the box below and click the "Add Tag" button.
Add Tag