Just warming up my BNSF family of locos and started to move strings of cars out of the way with my P2K Great Northern SW1200.
I was able to move 13 properly weighted 40’ cars with the loco across 5 turnouts and then spun out on the first curve. Got me to thinking…typically, how many cars would the real loco be able to shunt at a time? (of course it would depend if they were loaded or not…but supposing they were empty? 1200 hp is nothing to sneeze at.)
Interestingly, in my case I called out the ATSF 44 tonner to push on the other end and this did the trick…even with the bantam weight of the little guy!
Depends upon several factors, which is probably not what you wanted to hear. If you wanted to just switch with them in a flat yard you could move a whole group, many more than 13. If you wanted to use it as a road switcher(speed) then 13 cars should be reasonable. I am going to guess that your curves are sharper than most on the prototype, but in the city some very sharp curves did exist. Some trains would go down a city street then make a right hand turn into a warehouse, and a 18" radius HO curve could resonably approximate that. The NYC would use two SWs as the hump engine in the Toledo Stanley yard, frequently with a slug in between that was built from an old electric locomotive. The set was dedicated to hump service due to the large cables to power the traction motors in the slug. They would get power from the two SWs. But they would push 75 car trains over the Stanley Hump, at 3 mph(speed), and that was with friction bearings in the trucks. Damp rail can be another problem, or a bowl yard with damp rail is even worse. So you see it depends:speed, curvature, grade, rail condition, and even how long you want to pull max amperage.
The prototype SW 1200 could easily handle 50 - 60 or more mixed loads and empties under normal conditions (is anything on the railroad ever normal?). Have seen them get as many as 100 mostly empties moving.
As you have already done, if there’s another engine around there’s nothing wrong with having it give a little shove to get through a tight spot or to get you started.
The SW1200 has 1200hp and weighs in at 245,000 lbs and has 74,000 lbs starting TE at 25%.
So, she could lug 40-50 cars on the flat switching.
Now enter all things railroad…
The real number of cars pulled would depend on the rollibility of each car and the weather so,25-30 cars would be a realistic number before wheel slip at start.
The proto loco COULD move a larger number of cars than it was typically used for. There were obviously lots of variables - tangent/curved trackage, quality of track, siding lengths, weight/size of cars, level or hilly trackage, possible RR or area restrictions as to train length or speed, etc., etc.
In addition, I suspect RRs did not want to push their locos to the extreme - which would tempt breakdowns and accelerate wear. So in this regard they would double up the locos or reduce the number of cars moved.
Unfortunately, you cannot expect a model of any locomotive to perform like the prototype when it comes to pulling power or ability to pull a certain load. Lack of weight is the biggest problem with models.
Many railroads routinely use/used two switchers back to back (or nose to nose) when switching in a yard. It allowed the engines together to strain less when moving longer cuts of cars, and allowed an engineer to run the engines from the cab which gave him the best vantage point on the work being done.
Switchers used as road engines on a branch line would also often be back to back, so the engineer could just move to the other cab when the train reached the end of the line and was starting back toward the main.
Yes, I guessed that was the reason so many locos are MU’d even in yard work.
I can see a video online of a couple of SW1200s pulling 45 cars on a branchline.
Hi, Cacole…no, that would be crazy…and no one has room in their basement to run 100+ car length trains that I see with three or four Dash8/9 on our line. Even if I put four Dash 8s or five SD45s together I do not have the space on the bench to put a long train together. I just lash them up and run 25 to 30 cars for the show of it.
You’re right: I could run 100 car trains, but they’d tie-up the entire railroad. [:-^] Just for fun, I ran a 71 car train behind these four SW1200RS diesels (modified Athearn BB SW7s):
I have several 2.5% grades and very little straight track, and while the locos could have pulled more, having the train stretched out over several (non-NASCAR - i.e. not all in the same direction) curves and on several grades, both uphill and down, at the same time made train handling “interesting”. I would expect, on level track with wide curves, that each loco would handle about 50 cars.
I have a new $38.00 Walthers trainline GP9M. At half throttle it can pull 42 metal wheel cars + 11 plastic wheel cars around my 35 foot main line. Also has 5 feet of track at 1.7%. If you follow the NMRA standards your railroad will run well. Have fun. Going to work in Alberta for a month or so. Shutting down my railroad for now.
Can’t speak for the real thing but my Athearn R-T-R F7 pulled 46 cars at a good scale speed. Now, with that said, they were all club cars and mixed with 40’ old time cars and 50-90 foot modern cars, and I don’t believe the club had any standard like following NMRA specs. I don’t remember if I pushed it through any curves, but the main is 36"R.
Now, with that all said, I also need to say I did stall out. There was an operator ahead of me, trying to show off his Big Boy and 47 car ATSF reefer train, but had problems with a car and decided to do a ‘quick fix’. I slowed the train down to a crawl and at first the other operator decided to just take off the car and getter going so I had the chance to crawl then speed back up, sorta. With low throttle I had no problems extremely slowly accelerating, but a little access throttle started it slipping. What really killed me was the fact the other operator THEN decided the car would be a quick fix with the trucks and stopped his train on the main to take 10 minutes to do so. I could not get going again, she just slipped then stalled.
Now, with all that said, I nocked off a few cars down to 36 or 37 cars and had no further problems, through the curves, the switches (I do believe #7), and didn’t even blink accelerating up a small incline then into a curve, no more than 28".
As I said though, I have no clue how this all relates to a prototypical F7. These are just my experiences. i also have an Athearn R-T-R F45 (Santa Fe) with about a 45 car train. Had no problems, remained in low throttle and didn’t loose any noticable speed. Mind you, another operator had a problem car so while the train was 45 cars or so long I was actually pulling my 35 car train and pushing about 10 cars of his train. It certainly was a bit odd to look at the front my train and see a bunch of cars in front of my engine that I did not put there.
Thanks, Kootenay and Brakie and all you guys with real life experience/info. That is why I enjoy the forum so much…getting the real picture. I used to really enjoy my Great Uncle telling me the stories of his life as a motorman for 30+ years on the CTA trollies. Kind of reminds me at times of him when I get you fellows recounting the old times on the job.
Yes, one of my uncle’s favourite stories was the one of the young motorman who took his trolley off on the wrong route (can’t remember how) and got it stuck in a tunnel (going under the Chicago River, I believe) because it didn’t have enough ummph to climb the grade on the other side. As I recall the young man was mightily embarrassed as the units were sent out to pull him out of the way so rush hour could continue.
This is a good point. When kicking cars, the ability to get stopped quickly was just as important as the ability to give a quick kick. If you got too far along the yard ladder, you’d have to back up to get into your next track. A GP9 and an SD9 weren’t too much different kicking cars, but the SD could get "em stopped in a shorter distance so as to be in position for the next kick.
Sometimes, when handling a long cut of cars that had the air bled off, an engineman would want maybe 5 or so cars next to the engine to be aired up for stopping power.
Some roads used brake sleds to aid in getting stopped. Typing “brake sled” into the forum search box or into Google will bring up some info on them.
Streetcar men have as many good stories as old railroaders regarding run aways, power-off situations, wrecks and various riders. When the PCC cars were new they were restricted to certain runs as this Company’s cars did not have a trolley pole on each end and had to be turned back on a loop, rather than a wye or changing ends. Other older single-man cars had a trolley pole at each end and a Motorman’s position so he could back the car up, where necessary, or just return without turning the car at all on a dead end single-track route. On a two-man car, the Conductor would stand at the rear guiding the trolley pole on the wire with the rope as the car backed up, signalling the Motorman with his pull cord bell, or yelling if the car was empty. Some one-man cars had a special controller and removeable handle at the rear just for backing up. Anyway, this Motorman took a PCC onto a miles-long single-track route which dead-ended and reached the end of steel. The track was once an Interurban route which had been abandoned beyond the present end of steel and did not warrent double track or a wye. The whole route lasted because of and only until the end of the War and then was promptly converted to busses. Surprise!, there was no way to back up this type of PCC safely on city streets for several miles. No Conductor, and rear windows small and cannot be opened. He walked to a payphone at the cafe at end of steel and called the Dispatcher, who said to leave the car there and come back on the next regular car. That night they went with an automobile and flagged the PCC back running in reverse for many miles to the next loop or wye. No, I do not know why they did not just tow it back with a regular double-end car after hours. Thank You.
On the PRR we routinely kicked cars with a SW1200…The engineer was a old engineer and he worked the sander and then the engine brake to stop on a kick…He was notorious about over kicking cars.
Probably the best engine to work a yard would be a GP7/9 or a SD7/9.
