I know that RRs base the number of engines on the weight of the entire train and not the length, but can anyone tell where to find out how much weight per engine.
It’s a bit tricky - each road usually gives a given locomotive type a tonnage rating for each operating region, based on the conditions in that region.
CN tends to run around 1HP per ton of train on the Champlain District between Mont-Joli, Quebec and Halifax, Nova Scotia - my “home” road. In flatter terrain, this goes down. In the mountains, it goes up.
Wish I had more to offer…
There’s also the factor of speed and equipment location. An SW7 will move alot of cars, but not very fast. That’s why you see passange unit with 2 engines pulling 4 cars. Also, if railroad aren’t careful they end up with all there locos at one end of their line because loaded cars require more power than empty returns. So they put extras on return train to get the power where they need it.
There’s also an issue of maximum drawbar pull. Couplers can an will break if too much stress is put on them. I know some roads have a maximum number of Axles allowed on the head end of the train, which will vary with geography. BNSF IIRC also rates AC motor and high adhesion units with a conversion factor (1.5 and 1.25 IIRC) to account for their higher tractive effort per axle.
bring me up to speed plz
HORSEPOWER
I know that RRs base the number of engines on the weight of the entire train and not the length, but can anyone tell where to find out how much weight per engine.
It’s a bit tricky - each road usually gives a given locomotive type a tonnage rating for each operating region, based on the conditions in that region.
CN tends to run around 1HP per ton of train on the Champlain District between Mont-Joli, Quebec and Halifax, Nova Scotia - my “home” road. In flatter terrain, this goes down. In the mountains, it goes up.
Wish I had more to offer…
There’s also the factor of speed and equipment location. An SW7 will move alot of cars, but not very fast. That’s why you see passange unit with 2 engines pulling 4 cars. Also, if railroad aren’t careful they end up with all there locos at one end of their line because loaded cars require more power than empty returns. So they put extras on return train to get the power where they need it.
There’s also an issue of maximum drawbar pull. Couplers can an will break if too much stress is put on them. I know some roads have a maximum number of Axles allowed on the head end of the train, which will vary with geography. BNSF IIRC also rates AC motor and high adhesion units with a conversion factor (1.5 and 1.25 IIRC) to account for their higher tractive effort per axle.
bring me up to speed plz
HORSEPOWER