Hi all, a question today: until the advent of steering trucks equipped EMD SD70/75s, I was told Alaska Railroad had such tight curves that only BB locomotives were allowed. That's why before the SD70/75s the mainstay of the flleet were EMD Geeps. Does one of you know what this line's minimum curve radius is? Thanks for any reply, Dominique
They had 40-45 RSD1 units. Also had about 20 MRS1. A pair of E9A, and an E9B unit that was converted to a HEP car. Boxcab E50
Thought I had a condensed track profile book. But cannot find it. Those usually show curvatures. :sad: Boxcab E50
Oh, Alaska GP49, where are you??? I dunno if the curves prohibit use of 6-axle rigid trucks, but they certainly have wear issues otherwise on the rails!
I was going to reply earlier but I am not sure myself. I looked in the book, Alaska's Wilderness Rails and there is a picture of a CN SD-40. They could not run it because of weight. The bridges at the time could not take the weight of an SD-40. It made no mention of curves. I am trying to remember where I heard or read about curves on the Alaska. I know they have/had so me tight ones. I will continue to search as time permits. One place you might try is the Alaska Railroad Yahoo group. They might be able to give you an answer. If you find out, please let us know!
OK thanks for the input. I'm going to inquire. But if someone here knows the answer, I'm still tuned! Dominique
Yippee! I found my condensed track profile book! Will look through it a little later. But that should get us very close. Boxcab E50
Had a chance to sit down, and read through my profile book. Between Anchorage, and Fairbanks, I found numerous examples of 10 degree curves. Especially on the southern end. Most of these had speed limits of 25mph. I found two curves greater than ten. One mile south of Healy, a 14 degree, 30 minute. And at Nenana, a 14 degree. (20mph.) I really cannot see any reason these would stop use of six axles. The Milwaukee Road had many a main line ten degree curve. And some sharper radius. Over these, for decades, they operated S class 4-8-4, N class 2-6-6-2, Little Joes of 4+D+D+4, E7, E9, SD45, SD40-2, FP45, U33C, U36C, and more. Boxcab E50
Hi Boxcab, and thanks a lot for the input! But when you speak of the curves on the Milwaukee Road, are you sure it deals with the main line, and not 4-axle-loco operated branchs? Because today I remain sure I've read somewhere 6-axle locos were banned on the AK until steering trucks advent (and I hardly imagine an SD45 or a Little Joe on a more than 10-degree curve) . But if you speak about 14.5 degrees curves on the AK, it should be the explaination: I believe these are the sharpest curves on all the north american railroad network (unless a now withdrawn section on the CSX with, if I remember, a 17 degree curve - on which only 4-axle locos run). Dominique
Keep in mind, there were only the two 14 degree curves noted in my profile book. They may have banned six axles. But that doesn't mean they weren't useable. I can't prove one way or another why. Sometimes policies are adopted, that don't truly make sense. And that was, after all, government operated.... 'Nuff said there! As noted earlier, they had dozens of six axle units in use, in older ALCo units. Supposedly, there are some major line upgrades in the works, or already in progress. Which might even eliminate a few tighter curvatures. And other limiting factors. The Milw info I quoted is indeed found on their transcontinental main line. Granted, that's not along it's entire length. But for example, there were a bunch on the west slope of their Cascade Mountain crossing. I didn't take the time to dig out blueprints, etc, for their Bitterroot grades, etc. Boxcab E50
Ken, The tightest curve I can think of on the Milw cascade crossing was McClellans butte. But I may be wrong on that.
There are a bunch of 10 degree curves between Cedar Falls and Rockdale. And one that is about 11 degrees. I don't have time this morning, to get out my blueprint. But over those tracks, ran the many engines I'd earlier noted. Without difficulty. That is, until Chicago made it impossible to maintain the tracks...... Boxcab E50
The D&RGW has a 15* curve in Byer's Canyon. They used to run 3600-class 2-8-8-2's, and 1400-class 2-10-2's up thru that territory. That curve was run with any 6-axle power the road could find. LaVeta Pass had allowed the 3600''s and 1400's during steam times, but disallowed SD45's on the same trackage. Reason could be diminished gandy dancer personnel after the transition for proper track maintenance, or anything else. Might be the expanation for ARR as well.
I can imagine high horsepower, heavy units with their greater adhesion, might tend to climb over the rail on tight curves, so maybe that is another factor. Any real trainmasters out there?
They have been straightening out some of the rail up there. I think any prior ban of locos had more to do with bridge limitations than curvature. Track maintenance up there is a real challenge.
I think Pete is correct. I will do a little further asking but here is this excerpt: Taken from "Alaska's Wilderness Rails" by Ken C. Brovald "CN SD40 N0. 5161 is in Anchorage on April 20, 1983 to dedicate a 425-foot 5,249-ton, 56-car capacity rail barge for 'Aqua Train' service between Prince Rupert, BC, and Whitter, Alaska. This occasion marks the first time a foreign line locomotive and business car has been on the Alaska Railroad. The engine proved to be too heavy for the bridges and was left in Anchorage, while lighter FP7s pulled the 300-passenger special to Whitter. Ken C. Brovald photo"