Tehachapi Loop

[Cardinal51]

http://www.youtube.com/watch?v=-UWm2PAJkQU

Amazing video, would be great to have this in RS.

But . . errrrr . . . why was this loop built ? The grade does not seem that steep.

The image below for a great and impressive overview of the area !

[Bananarama]

The loop was built at a time when locomotive tractive effort was poor, and the ruling grade is in excess of 2% between Caliente and Tehachapi. If the line were new, then likely the grade would have been straighter and steeper between Bealville and Marcel, but not more than a fraction of a percent. FWIW, there's currently a double-track program to take place over the new few years between Bena and Marcel that will daylight or go around many of the tunnels. If you're nearby or will be in the area soon, I suggest getting some pics of the classic locations before they're gone for good.

[Chessie8638]

The loop was built to keep grades to a 2% maximum over the pass. Remember 2.2% is the "standard" for a well engineered mountain railroad (the loop itself is 2.2%). That whole line is an example of primitive "hill side to hill side" building. Later on they just built fills and tunnels to keep grades below 2.2% where possible on other lines through mountains in the East and West alike.


Another example is Williams Loop on the Western Pacific. They wanted to keep grades down so they just looped the railroad over itself. The result is a overall 1% compensated grade.

Why would you build a railroad with say 4% grades when you can just build a loop and keep the grade down to 2% or so.

[glenn68]

If you want loops in RW, Get Colton and Northern.

[Bananarama]

Long ago I laid track between Mojave and Bakersfield. Unfortunately, however, there are no easements for super-elevation (albeit noticeable SE only exists between Sand Cut to Illmon, Marcel to Tehachapi, and Cameron to Mojave). Track grade and curves are smooth as a baby's butt, and I hate to have to relay the whole line for the effect for such a slow speed line, introduce the RW-lurch while in cab, and also risk destroying the yards on either side.

Here's an overview map showing the line and a portion of the Jawbone (L0one Pine Branch) and the ATSF to Barstow out of Mojave (lower-right) and the Arvin and Taft lines near Bakersfield (upper-left):



Looking East Caliente viewed from Tunnel 1:



Looking East towards Cliff from Tunnel 3 at Bealville:



The Loop looking West from Tunnel 10:



Marcel looking East (trees are placeholders only):



Looking South at Mojave. The wye leads to a cement loading facility several miles East:



I created some structures for Mojave. Tehachapi and the Loop Ranch, but haven't placed them yet. I re-DEM'd the route a few months ago to take advantage of RW's increased draw distance, but haven't worked on it much since. After all, I still have Selkirk to finish.

[PapaXpress]

Why do you tease us so...

[Bananarama]

Why do you tease us so...

Because I am evil.