Ok thanks.
@Mark V. Spadaro posted:So IRL, if I understand correctly, a road switcher, doing both yard switching, and road assignments, would receive dual control stands, and a road switcher, doing road trains, would get a single control stand?
I think there may be a general misunderstanding about diesel locomotives having dual control equipment.
The most significantly expensive options for GP7, GP9, SD7, and SD9 locomotives were:
- Dynamic braking equipment;
- Steam generator equipment (steam generator, water tank, steam piping, in-cab control and steam gauge, communicating whistle);
- Dual controls (control stands and air brake stands);
- Cab signal or Automatic Train Control equipment * .
I have them listed in decending order relative to cost. If the locomotive was also equipped with Cab Signal or Automatic Train Control equipment, then the cost of dual controls was significantly higher.
Dual controls on each unit of large orders of locomotives amounted to substantial extra cost. Most railroads got by without dual controls, or some others had a small number of units equipped with them for a particular purpose, such as branch line passenger service or units dedicated to commuter service. Therefore, it was not common, except on a few railroads.
The really big users of dual controls on first generation EMD GP and SD units were Norfolk & Western (which had several hundred equipped with 24-RL and 26-L air brake schedules and the long hood specified as Front) and Burlington (which had at least a hundred with the short hood specified as Front). Burlington's Fort Worth & Denver subsidiary dieselized with SD7's and SD9's, and a couple of Geeps, all equipped with dual controls and Number 6 air brake schedule. The Burlington proper (Chicago Burlington & Quincy) had at least some SD units with single control equipment. I cannot say what the Colorado & Southern subsidiary did, but, overall, Burlington and its subsidiaries had a large number of dual control-equipped GP and SD units.
Some commuter operations (Jersey Central was one, I am told) had smaller fleets of dual control-equipped GP7's and GP9's, as well as some Alco RS2/RS3 units with dual controls, some of them having the extra-cost 24-RL air brake schedule.
Dual controls were quite an expense for a feature that might not be used every day, whereas dynamic braking was going to return every penny of its cost. Therefore, only a small number of railroads equipped their units with dual controls and adjusted their operating practices to effectively use the expensive feature.
Norfolk & Western marched to its own drum in numerous practices and its locomotives were different from the majority of other railroads in many respects, dual control equipment being one of them.
* Normally, locomotive equipment manufacturers built-in the air brake and electrical features, circuit breakers, wiring, brackets, piping, and connectors necessary for units to be equipped with ATC, ATS, or Cab Signals. The actual devices and receivers that interfaced with the signal system (manufactured by General Railway Signal or Union Switch & Signal) were typically purchased directly and separately, and then installed by the railroad after delivery, in a sort of "plug and play" manner.
Good explanation! Enlightening! Thanks.
