Western Railroad Discussion > Big Ten Curve (Kevin's Ski Train Photo Reminds Me...)

Kevin Morgan posted a great photo of the Ski Train descending off the Big Ten curve on Saturday:
http://www.trainorders.com/discussion/read.php?1,1356083
That photo and thread reminded me of something I've been meaning to post, and now seems like a good time since I've got another visual aid...

Many of you have probably heard a reference to the "Big Ten" AND "Little Ten" curves at some point. If you're like me, you probably assumed that the "Little Ten" curve was the left-hand (as you go westbound) curve leading into the right-hand "Big Ten" curve (where the wind-break hoppers are located). If you made this assumption, you, like me, were wrong!

First, let me note that in Kevin's picture, the train is headed eastbound (geographically, the locomotives are pointed roughly north-northwest). The Ski Train, in the photo, has pretty well *finished* negotiating Big Ten (which is, indeed, the curve which is partially protected by those hopper cars); At most, the last car is just rounding out of the curve. Now, for those of you who made the same faulty assumption I did, you would probably assume that the train is now right smack in the middle of the Little Ten curve (or that perhaps the Little Ten curve is right smack in the middle of the train, given that the train is longer than the curve). Well, that curve is NOT Little Ten; It is actually a compound curve made up of four sections of varying curvature, all left-hand curve as looking westbound, but none sharper than 8.33 degrees!

Little Ten curve does exist though, just slightly further east. Here is a Terraserver image that will help you visualize all of this:
http://terraserver.homeadvisor.msn.com/image.aspx?T=1&S=12&Z=13&X=597&Y=5514&W=1
Big Ten curve is the curve seen in the lower right section of the photo. Little Ten curve is seen near the top of the photo, and is a left-hand curve as viewed westbound. I figured all this out just by looking over DRGW and SP Grade and Alignment Charts (thanks to Nathan Holmes and his wonderful DRGW site here:
http://www.drgw.net/

Nathan has G/A charts posted (for this area) from 1970, 1989, and 1992. The curvatures in the area remain pretty much unchanged over that time, but one thing that did happen sometime in the 1989-1992 time frame (I couldn't find the exact date) is that Rocky siding was extended westward -- right through (around) Little Ten curve! On the Terraserver image above, if you click on "Topo Map" it shows you where Rocky siding is, but it still shows it ending short of Little Ten curve. From the aerial photo, though, you can kind of see where the siding ends now -- on the straight section of track leading into the compound curve I mentioned above (which in turn, after a short tangent section, leads into the Big Ten curve). (Note that following the track further RR-westward takes you through another right-hand turn, after which you would find the east end of Clay siding.)

Here are the Grade/Alignment Charts for the area, thanks to Nathan:
1970:
http://www.drgw.net/gallery/TC1970-DENDOT/denver_dotsero_1970_MP15_20_1725x635?full=1
1989:
http://www.drgw.net/gallery/TC1989-DENDOT/denver_dotsero_jan_1989_MP15_20_2640x2040?full=1
1992:
http://www.drgw.net/gallery/TC1992-DENDOT/denver_dotsero_1992_MP15_20_2640x2040?full=1

If it's your first time looking at these types of charts, it take a little getting-used-to. Pay special attention to the information near the top of the charts -- this is where the information on curves (direction, degree, length) is located. Once you get oriented, they're really fun (and informative!) to look at...

Other stories have been promulgated about where the "Ten" came from. I found one of them while searching (unsuccessfully) for the date that Rocky siding was extended. It said that the name was coined because the loops look like a "10" on a map. Ummm...I don't think so!

Also, I've heard different stories as to what the hopper cars forming the wind break are filled with. My take is that they are filled with earth (dirt). I don't think they are filled with rocks, as some suggest (except whatever rocks would come with a few frontloader-scoops of dirt), and I don't think they are filled with cement. I have passed them many times on the Ski Train, and in the summer there are always many weeds and shrubs, and even a tree or two, growing in there. You can just barely see the top of the dirt at times.

I hope at least a few of you found this informative if not interesting!
Take care,
-Wes

Here are links to a couple photos of Little Ten (on my website)

Summer daylight:
http://members.trainorders.com/cimascrambler/new_work_gallery/pages/2005-07-D-2384.htm

Winter moonlight:
http://home.earthlink.net/~lunarlightphoto/moonlight2/pages/2006-02-D-5540.htm

I think Little Ten is more photogenic from down low, while Big Ten is best seen from up on Blue Mountain - it is just too big to see when you are down by the tracks!

- Kit

Those hopper cars were filled with dirt and welded to the rails with weed killer added to the dirt, which they never reapplied as trees are growing out of them.

Nice post Wes!

You are absolutely correct that the hoppers have dirt in them. I was told at one point that they had both cement and dirt in them (dirt covering the cement), but that may have been in error. Don't recall the source for that. I'd trust WAF in that they are filled with only dirt, so scratch the cement portion I suppose.

If you want to see some up-close shots, go to my Train Log page and scroll to the bottom. There is a link to a Train Log on Big Ten Curve. There is a synopsis as well as pictures that I took back in 2002:
http://www.coloradorailfan.com/TrainLog/logs.asp

Enjoy!

Kevin Morgan
Arvada, CO
ColoradoRailfan.com

One early problem with the dirt filling the cars was the sand blasting trains got when wind picked up that dirt and blew it forcefully across the mainline. I heard the RGZ had to have several windows replaced. I haven't checked, but maybe they put gunnite or cement over the dirt.

KK

Seen them close up, looking down somewhat from Amtrak. Of course, they need a gardener to cut all the bushes and trees out.

They aren't wind breaks... they are window boxes with a thyroid condition! BTW, the best view I ever had of a high-jumping deer vaulting a fence was at that curve while aboard the Desert Wind.
...Lorenzo