I need some help understanding how a control tower might be placed and used for an interlocking during the 1940's timeframe with non-CTC, train order and timetable operation and automatic block signaling. This track arrangement has: double track mainline running east-west. passing track with siding that leads to multiple industrial tracks crossovers between mains at either end of the passing siding to allow trains from westbound main to use passing siding and access industries. branch line coming into westbound main at east end In the somewhat crude diagram, arrows indicate normal traffic direction – right hand running. Eastbound is to the right, westbound to the left. This arrangement with the branch line seems to require an interlocking plant. So, questions: Is this an interlocking? Does the interlocking include the crossovers at the west end of the track arrangement? Does the interlocking also control the passing siding? Where is the control tower placed? In the middle of the track arrangement, or toward the branch line? Or somewhere else? Thanks for any help George V.
I'd expect they'd site it closest to the point where the most switches and signals would need to be handled. Remember that in the era you note, most of these were connected with metal rods. The longer, the harder to throw and maintain. Regardless of them being completely manual ("armstrong"), electric, pneumatic or electro-pneumatic. If the distance was that great between your west and east, for that simple reason, there might have been two towers.
I agree with BoxcabE50. Plant visibility mattered as well. Assuming that you have one tower, having it centered where you have it would be preferred.
Thanks for the replies, guys. After thinking about distances and control rods needed, I'll put the tower between the two locations at the end of the passing siding. There's only three turnouts at the far end, and four or perhaps five at the near end if the siding to the industries is controlled by the tower (which may be appropriate given it's on the passing siding). Thanks, George V.
I think it's neat that you have an interest in interlocking towers and plant layouts. I share your interest and I've enjoyed seeking these out over the years. It's neat that we can keep this almost-extinct railroad tradition alive on our model pikes. Dan Maner's site has some nice photos: http://northamericaninterlockings.com This site has some good photos too and interlocking layout drawings as well. http://members.trainorders.com/nkp759/towerindex.html
