Professor Chaos posted:Hot Water posted:AmeenTrainGuy posted:I am a bit confused. Will the bigboy be able to run without a diesel engine coupled to it?
Hopefully, yes.
Why is it that the diesel engine has to do all the work while the steam engine is just there for show?
Lots depends on the size/weight of the passenger train behind and the grades. The diesel is also used primarily for dynamic braking on steep/long down grades. Previously, i.e. prior to 2011, many steam operations on the UP were operated without any diesel, in non-heavy grade territories.
Is there something about the way 4014 is being restored that will reduce its braking capability?
No. Steam locomotives essentially have no braking ability, unless they are running/moving light, i.e. without any train. One of the golden rules of operating a steam locomotive is; NEVER use the engine brakes when slowing a train!
Or does the need for a diesel on grades reflect some other change in the way 4014 would be operated today, vs when the Big Boys were in regular service?
Back in the days of steam, the train brakes were used, as that was the ONLY way of maintaining train speed on depending grades. With the advent of diesel, which were equipped with dynamic brakes, the use of train braking was drastically reduced, resulting in major reductions in brake shoe wear and wheel wear. The UP thus adds a modern diesel unit which can be used as need for addition pulling power with a heavy passenger train, and saves disc brake shoe and wheel wear, by using the dynamic brake on the diesel unit.
