Hello everybody,
right from the start I would like to state that I nerver have operated a locomotive and in all likely hood never will. Still this question has been in my mind for a long time and would like to ask the knowledgeable forum membership for advice.
When out on the road operating the locomotives do you really notice an extra 100 hp? Take for example the difference between an SD45 - 3600 hp an SD50 - 3500 hp and an SD60 - 3800 hp. So if you had a pair of SD45's on a freight one day and an SD45 and SD50 the next pulling a freight of equal weight over the same route would you notice a difference. Also how much HP do you need before you actually feel a significant change in how the train operates.
This brings up the question if it is the traction control system that really makes the difference. Does the change in HP have as great an effect on the locomotives performance as the change in traction control technology?
Thank you
Frank
"If you need a helping hand, you'll find one at the end of your arm."
Frank,
100-200 HP difference in that range of SD's really does not make a lot of difference. remember the SD45(3600 hp) was built in 1966-1971. The SD50(3500 hp, later 3600 hp) was built starting in 1980. By then, the electrical control gear has advanced quite a lot. That SD50 benefited from the '-2' electricals of the 70's, and the radar 'SS' wheels slip(something the SD45 never saw back in the 60's).
As you noted, the control systems improved and control of all that horse power was much easier. You need HP, which creates 'continuous tractive effort'. Without the new control systems, we would be stuck at the 3,000 hp level. Adding HP that you cannot control is of little value. Some of the engines of the late 60's with high HP proved that point.
Jim Bernier
Modeling BNSF and Milwaukee Road in SW Wisconsin
da_kraut wrote: Hello everybody,right from the start I would like to state that I nerver have operated a locomotive and in all likely hood never will. Still this question has been in my mind for a long time and would like to ask the knowledgeable forum membership for advice. When out on the road operating the locomotives do you really notice an extra 100 hp? Take for example the difference between an SD45 - 3600 hp an SD50 - 3500 hp and an SD60 - 3800 hp. So if you had a pair of SD45's on a freight one day and an SD45 and SD50 the next pulling a freight of equal weight over the same route would you notice a difference. Also how much HP do you need before you actually feel a significant change in how the train operates. This brings up the question if it is the traction control system that really makes the difference. Does the change in HP have as great an effect on the locomotives performance as the change in traction control technology? Thank you Frank
The way i see it Frank, its not entirely all about horsepower. A modern 3500 hp unit may pull better than an older 3600 hp unit! Theres also alot of other variables like the weight on drivers and number of drivers. Make a coffee, relax and have a good read through this guys web page, straight from the engineers mouth so to speak, he realy knows his stuff- http://www.alkrug.vcn.com/rrfacts/hp_te.htm
Its also a great website.
Hey Da-***: With 19 years of right-hand seat time for several railroads, I can tell you that you don't really "feel" the differences in horsepower as much as "notice" it. With 3 AC units on the head end and a couple of DMUs with 11,000 tons between, I notice that I'm able to accelerate out of slow orders much more quickly now than back in the day with a comparable number of -2's. If you're wondering about gettin' pushed back in the seat when you notch up, that kind of stuff doesn't happen, no matter what you're running.
BTW -- all the reading about this stuff might be "fun," but feeling a locomotive is more than academic. Snoop around your local terminal a bit, bro' up with the local crew, or check out an operating museum. You gotta get your butt in the seat and hand on the throttle to really appreciate what it's like.
Stay safe!
I always noticed the difference between the SD40-2 and the SD-45 , accelerating , pulling at high speed, they just seemed like they really wnt to go .
Slap a pair of 45's ,Light engine in notch 8 and you will get pushed back in the seat !
Hey, Randy -- you're absolutely right! Dang -- I was so focused on all that stuff hanging off my drawbar I nearly forgot about the cab hop I got to run over The Hill a long time ago. It was a lot of fun "punching" those two 45s and seeing how responsive they were... I was forced to turn down the radio because some yahoo kept screaming about slack action in the caboose. No appreciation for the finer things, I guess!
My only cabride was in an SD45 in a yard area, and I was impressed at how quickly it accelerated!! I would think you could notice a difference in horsepower and starting/pulling qualities. I know Warren McGee wrote that a lot of old NP hoggers weren't convinced diesels would work on freight (even though NP had been an early purchaser of FT's and later diesels) until NP got their A-B-B-A sets of F9's in the mid-fifties. Apparently a lot of engineers were converted after seeing how the F9's could couple up to a long freight and walk away with it with seemingly little effort.
The the BNSF rates their Dash-9's at 4400 hp and NS rates theirs at 4000 hp. You can't tell the difference. The big difference, and I mean big difference, is between the conventional units and the Hi-Ad units. When the Hi-Ad units came to the property, well, you could forget about kicking cars! The things just won't take off. On a district where there are a lot of speed changes and up and downs, a conventional EMD unit consist will make mince meat out of any Hi-Ad unit consist, because when you go to pull on 'em, they pull. Hi-Ad units just sit there and think about when they will start to pull.
The best set of units I ever had was two SD45's with two GP40's. That set of units would really walk the dog!
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When I was braking I could tell the difference in horse power by the floor vibration when starting tonnage from a stop other then that no.
Larry
Conductor.
Summerset Ry.
"Stay Alert, Don't get hurt Safety First!"
BigJim The the BNSF rates their Dash-9's at 4400 hp and NS rates theirs at 4000 hp. You can't tell the difference. The big difference, and I mean big difference, is between the conventional units and the Hi-Ad units. When the Hi-Ad units came to the property, well, you could forget about kicking cars! The things just won't take off. On a district where there are a lot of speed changes and up and downs, a conventional EMD unit consist will make mince meat out of any Hi-Ad unit consist, because when you go to pull on 'em, they pull. Hi-Ad units just sit there and think about when they will start to pull. The best set of units I ever had was two SD45's with two GP40's. That set of units would really walk the dog!
That is a great consist, The 40's keep you going while the 45s are making transition, smooth ride.
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