AmeenTrainGuy posted:Hot Water posted:AmeenTrainGuy posted:Could you elaborate more on "... and NOT just for dynamic brake."? What I don't get is how did the bigboy's stop long trains without dynamic braking but cannot stop 5 - 10 passenger cars?
You are losing sight of the fact that more than 70 than 70 years ago, all they had were train air brakes. Thus, all trains, both freight and passenger used nothing but the brake shoes, which were cast iron at the time, to slow and stop trains. In the modern era with steam specials/excursions the use of a diesel helper in dynamic braking on long down grades, is highly beneficial, plus saves the disc brake pads on the passenger cars. With that diesel "helper" MU'ed with the steam locomotive, it also can be used in power to stretch water & fuel usage on the steam locomotive. Maybe the steam locomotive is very capable of "pulling the train up the grade all by herself", but at reduced speed, to what point? Why beat the crap out of the poor steam locomotive for absolutely NO REASON, when just a bit of "help" from the diesel will maintain a higher speed and conserve fuel & water on the steam locomotive.
Thank you for the explanation.
So to summarize it seems like the actual steam engine is capable of doing all the work, but UP would rather preserve the life of the engine, get dynamic breaking, and reduce fuel usage by using a modern diesel locomotive to do some of the work.
Depending on the territory that will be operated over, essentially, YES. If there are no seriously long "mountain grades", the the steam locomotive should be able to handle most of the passenger train assignments unassisted. Such was done previous to 2010 with either 844 or 3985, when traveling east or south to such locations as, Chicago, Kansas City, St Louis, Houston, etc..
