Trains.com

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Mixing bowl of road units

5941 views
37 replies
1 rating 2 rating 3 rating 4 rating 5 rating
  • Member since
    January 2017
  • 2,980 posts
Mixing bowl of road units
Posted by NWP SWP on Wednesday, May 16, 2018 6:18 PM

I have heard of railroads typically keeping units of common manufacturers together but do railroads (past and present) typically keep the same model units together? Would a GP40 and SD40 be in the same lashup? would you see SD35s with 40s and 45s?

Steve

If everything seems under control, you're not going fast enough!

  • Member since
    December 2015
  • From: Shenandoah Valley
  • 9,094 posts
Posted by BigDaddy on Wednesday, May 16, 2018 6:55 PM

Only by random chance.  Yesterday I decided to keep track of the loco numbers I was seeing.  The transition era is my era and I don't know anything past GP and SD40's.  While I think I saw two SD40's in the same consist today, that was the first time in the several months I've been watching the webcams on Youtube.

Almost always they are by themselves on a short local train or in a consist with 3 or 4 more modern locos.  My observations may be skewed because I am watching webcams that have a lot of CSX.

I feel like I need those flash cards, like they used in WW2 to identify ship and airplane silhouettes.

 

Henry

COB Potomac & Northern

Shenandoah Valley

  • Member since
    August 2004
  • 573 posts
Posted by pajrr on Wednesday, May 16, 2018 7:20 PM

4 and six axle units were mixed during the time of those units. Railroads would mix units to get the horsepower that the train needed. Nowadays, mainline trains are mostly 6 axle units, with 4 axle units being used for local freights.

  • Member since
    January 2017
  • 2,980 posts
Posted by NWP SWP on Wednesday, May 16, 2018 8:20 PM

So you could see SD45 followed by a GP30, SD35, GP40, SD40, GP35, on the lead of a train?

Thanks I was just curious.

Steve

If everything seems under control, you're not going fast enough!

  • Member since
    February 2015
  • 869 posts
Posted by NHTX on Wednesday, May 16, 2018 9:04 PM

    Steven, other than required horsepower and which way the cab of the lead unit was facing, there are four other considerations I can think of when building a power consist: (1)  minimum continuous speed.  Will the train spend a consderable amount of time crawling over grades at maximum power?  (2)   Maximum speed required by schedule.  Don't put a unit that is geared for 50 mph on a train that is expected to run at 65 or 70 mph most of its run.  (3)  Dynamic braking.  Units without DB were operated in the same consist as DB equipped units but, at least on the Southern Pacific, they had to have pass-thru wiring to pass DB commands from the lead unit to those against the train.  SP limited most consists to 18 axles of DB, counting from the unit coupled to the cars.  The dynamics on everything else had to be isolated.  (4)  Another SP practice was the positioning of SW-1500 and MP-15AC units in a road consist.  First, to operate in a road consist, the "little" units had to have coupler swing limiting blocks in their draft gear.  Then, they must be cut in right behind the lead unit, and the lead unit's DB cut out.  Not more than two SW-1500/MP-15AC shall be in a power consist with road units.  When making a reverse move with switchers in the consist, the lead unit must be isolated (not loading) because the higher horsepower of the road lead unit vs. the switchers  tends to jack knife the switchers due to their much shorter wheelbase.  As far as mixing units of different manufacturers and horsepower, it became less of an issue as the first generation came to a close especially on roads with extensive rosters.  One of the last examples of pure consists I saw was on the Southern Pacific in the very late 1970s.  They chain-ganged four unit sets of 7600 series of consecutively numbered GP-40-2s into "fuel-saver" sets.  These locomotives had special equipment that dropped units back to idle, once the desired speed was reached. All 12000 hp may have been necessary to get the train up to track speed but it only required 6000 hp to mantain that speed so, to save fuel and other maintenance costs, two units would drop to idle until their power was needed again.  As noted in another post, if you have an interest in a railroad, try to get a copy of their employee's timetable for the division and era that interests you.  Most of this info came from the SP ETT. 

  • Member since
    January 2017
  • 2,980 posts
Posted by NWP SWP on Wednesday, May 16, 2018 9:29 PM

I recently saw a picture of a BN freight that had SDs, GPs, Fs, and a switcher all in one lash up.

At the club they tend keep power in the same groups so GP10s with GP10s, SD40s with the same, ect... I find it a bit boring, thats why I was asking as my collection grows.

Steve

If everything seems under control, you're not going fast enough!

  • Member since
    August 2003
  • From: Collinwood, Ohio, USA
  • 16,226 posts
Posted by gmpullman on Wednesday, May 16, 2018 9:40 PM

NWP SWP
I recently saw a picture of a BN freight that had SDs, GPs, Fs, and a switcher all in one lash up.

Often, but not always, the switcher was being carried dead-in-tow to a maintenance facility for its periodic inspection or other work that couldn't be done at a distant terminal.

 

Regards, Ed

  • Member since
    October 2008
  • From: Calgary
  • 2,043 posts
Posted by cx500 on Thursday, May 17, 2018 2:00 AM

In the mid-50s you were more likely to see matched sets of road power, in part because the different manufacturers had not made their MU connections fully compatible.  That was soon corrected.  So, you could have an RS-3 leading an SD40, or vice versa, and a third unit might easily be a B-unit.  I once saw an ABA set of cab units, one each of F-M, EMD and Alco design.

There are exceptions to be aware of.  Switchers mostly did not have any MU capability and would be towed dead behind the operating power.  The few that did have MU mostly had a simplified version and would only MU with a similar unit.  Most Baldwin road engines had a completely different system and would only MU with another BLW.

One factor that sometimes continued to lead to matched power sets was when a small roster of "oddball" locomotives were assigned to a terminal to simplify maintenance.  In the 1970s that tended to happen with Alco designs, as well as the other minority builders.

  • Member since
    February 2015
  • 869 posts
Posted by NHTX on Thursday, May 17, 2018 5:35 AM

      Instructions for the building of a power consist were formulated by each individual railroad, often after an event involving some expensive noise and gritted teeth.  The Southern Pacific, San Antonio Division employees timetable, effective April 24, 1977 contains the following on handling switchers WITHOUT alignment control couplers dead-in-train:  provided the train does not exceed 800 tons, they may be moved on the head end.  On trains of more than 800 tons, these engines must be moved not less than five cars nor more than 10 cars ahead of rear of train and behind any helper engine.  Not more than two of these engines may be moved in a train and, when two are moved, they must be separated by a car no longer than 50 feet.  Also, if a switcher is operated in MU with a road unit, the switcher must be the lead unit, if reverse moves are going to be made.  It's all about coupler swing, jack knifing, and track damage.

  • Member since
    July 2006
  • From: Northfield Center TWP, OH
  • 2,508 posts
Posted by dti406 on Thursday, May 17, 2018 7:16 AM

I have a video of the Wabash which shows an FM Trainmaster, Alco C424, EMD F7s, GE U25b and EMD GP35 all hauling one train into Detroit from Chicago.

Rick Jesionowski

Rule 1: This is my railroad.

Rule 2: I make the rules.

Rule 3: Illuminating discussion of prototype history, equipment and operating practices is always welcome, but in the event of visitor-perceived anacronisms, detail descrepancies or operating errors, consult RULE 1!

  • Member since
    September 2003
  • From: Omaha, NE
  • 10,614 posts
Posted by dehusman on Thursday, May 17, 2018 8:35 AM

NWP SWP
I have heard of railroads typically keeping units of common manufacturers together but do railroads (past and present) typically keep the same model units together? Would a GP40 and SD40 be in the same lashup? would you see SD35s with 40s and 45s?

It all depends on the railroad, the era, the train and the location.

Some railroads kept the same make and model together on some trains and mixed them up on other trains.  Some trains always had a certain unit leading.  Some trains only had 4 axles, some only six axles.

For example, in the 1990's and 2000's on the UP, coal trains had sets of GE C44AC's almost exclusively.  Intermodal trains had sets of C44-9's and SD70's.  Meanwhile on manifest (general freight trains) in the southern part of the railroad they could have any 6 axle engines.

On the MP and the RDG 6 axle and 4 axle engines were mixed on road freights.

It just depends.  There are vaild reasons for both strategies and both are used by the railroads, possibly even the same railroad at the same time.

Dave H. Painted side goes up. My website : wnbranch.com

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Thursday, May 17, 2018 9:41 AM

 CNJ and WM did a lot of that too. Found a picture on another forum of a CNJ train with a GP7 in the lead, with an RS3 in the middle and a Trainmaster on the rear.

 There a picture in one of the Reading books with an RS3, Alco FB, GP7, and something else (or something like that) which begs to be modeled, mainly because the middle door on the FB is open.

                                      --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    January 2017
  • 2,980 posts
Posted by NWP SWP on Thursday, May 17, 2018 10:02 AM

I wish someone (like Athearn) would produce a DD35, GP35, and SD35 for SP or UP. That'd be a sight a 6 unit set of 2 GeePs, 2 SeeDs, and 2 DeeDs

Steve

If everything seems under control, you're not going fast enough!

  • Member since
    September 2003
  • From: Omaha, NE
  • 10,614 posts
Posted by dehusman on Thursday, May 17, 2018 10:16 AM

The original concept was that the DD35 was only going to be a B unit and would have a GP35 on each end.  That keeps the horsepower per axle even.  GP35 = 4 axles 2500 hp, DD35 = 8 axles 5000 hp.  The MP did that with GP38's and SD40's. Both units have 500 hp/axle.  The SD35's probably didn't run with the DD35's that often. 

Dave H. Painted side goes up. My website : wnbranch.com

  • Member since
    January 2017
  • 2,980 posts
Posted by NWP SWP on Thursday, May 17, 2018 10:28 AM

Here's one such occasion.

Here's three Centennials and two other units on the lead of a train.

Steve

If everything seems under control, you're not going fast enough!

  • Member since
    June 2007
  • 8,863 posts
Posted by riogrande5761 on Thursday, May 17, 2018 10:53 AM

NWP SWP

I have heard of railroads typically keeping units of common manufacturers together but do railroads (past and present) typically keep the same model units together? Would a GP40 and SD40 be in the same lashup? would you see SD35s with 40s and 45s?

D&RGW didn't make a fuss about keeping like road units together.  They freeling mixed 4 axle and 6 axle diesels together as evidenced by countless photo's.

Of course they also ran sets of tunnel motors together, and other like types.

Basically you can do what you please if you are freelancing since RR's did what they pleased.

So go ahead, "hook'em" together like those long horns in your siggy Laugh

 

As far as those UP DD engines, unless you have a LARGE layout with large radius curves, you might want to "steer" clear of muing 3 of those together.

IIRC, the DD's were typically ran as a sandwhich, two of them with an SD40-2 in the middle.  Athearn ran the UP SD40-2 type a couple years ago which were used with the DD's.

Rio Grande.  The Action Road  - Focus 1977-1983

  • Member since
    January 2017
  • 2,980 posts
Posted by NWP SWP on Thursday, May 17, 2018 2:07 PM

Correction, that picture has not three but FOUR Centennials and what appears to be a GeeP.

As far as mixing units I'll take the Bull by the Horns and for the June 2 Op Session at the MSMRC I'll get two Burlington GP10*s and two Burlington SD40-2s and run them as a consist if no one has them on a train. (*I think they're 10s but not completely sure) I'll take a few pictures of them running, which units should lead? Do I sandwich the Geeps between the Seeds or vice versa, or do I alternate Geep, Seed, ect. Or vice versa?

Steve

If everything seems under control, you're not going fast enough!

  • Member since
    January 2017
  • From: Southern Florida Gulf Coast
  • 18,255 posts
Posted by SeeYou190 on Friday, May 18, 2018 7:54 PM

The STRATTON & GILLETTE never mixes models in a locomotive consist. I just like the way it looks better.

.

There was a railroad, for some reason I think it was the BURLINGTON ROUTE, that ordered GP-9s geared the same as their F units to be used as boosters. They would commonly run consists of F unit A, F unit B, GP-9, F unit A.

.

I hate the way that looks to have a GP in the middle of an F unit A/B/A set.

.

In the movie Runaway Train there was an F unit in the middle of the consist that caused problems in getting the train stopped.

.

I think that is more than enough fiction and conjecture for one post.

.

-Kevin

.

Living the dream.

  • Member since
    March 2012
  • 1,134 posts
Posted by PC101 on Friday, May 18, 2018 9:41 PM

I can run two, three, some times four unit matched sets, two, three and again four units in a mixed set and for road names, I can run at least three different road names (PRR-NYC-PC) in the same consist. Never boring. Hows that for variety? I love the PC.   

  • Member since
    April 2003
  • 305,205 posts
Posted by Anonymous on Saturday, May 19, 2018 11:38 AM

NWP SWP
At the club they tend keep power in the same groups so GP10s with GP10s, SD40s with the same, ect... I find it a bit boring, thats why I was asking as my collection grows.

This is likely more due to the locomotive models not being speed matched.  You can typically pull three new locomotives out of the box from the same manufacturer/manufacturing run and they will run "okay" together.  Start mixing manufacturers, and you end up with one unit doing all the work if you haven't speed matched them well.

Just a guess.

 

  • Member since
    March 2012
  • 1,134 posts
Posted by PC101 on Saturday, May 19, 2018 11:59 AM

.

  • Member since
    March 2012
  • 1,134 posts
Posted by PC101 on Saturday, May 19, 2018 12:06 PM

BMMECNYC
 
NWP SWP
At the club they tend keep power in the same groups so GP10s with GP10s, SD40s with the same, ect... I find it a bit boring, thats why I was asking as my collection grows.

 

This is likely more due to the locomotive models not being speed matched.  You can typically pull three new locomotives out of the box from the same manufacturer/manufacturing run and they will run "okay" together.  Start mixing manufacturers, and you end up with one unit doing all the work if you haven't speed matched them well.

Just a guess.

 

 

That would be my guess as well. If using Digitrax two knob controller at least two different makes and model locos. could be speed matched to run together.

  • Member since
    February 2002
  • From: Mpls/St.Paul
  • 13,771 posts
Posted by wjstix on Sunday, May 20, 2018 11:08 PM

Railroads pretty much used whatever worked. Sometimes, when new, a group of engines might be run together regularly, but in time they were all mixed together. MN&S sometimes ran 4 EMD end-cab switchers with an SD-39.

There's no particular order to how the consist would go together, except if possible railroads like to have the lead and last trailing engine facing away from each other, so the whole consist wouldn't have to be turned to run back to it's starting point. 

Soo Line F3 and F7 A-units didn't have m.u. connections in front, so they would have to be first or last...so F3A-GP9-F7A, with maybe an Alco thrown in the middle too. 

Stix
  • Member since
    September 2003
  • From: Omaha, NE
  • 10,614 posts
Posted by dehusman on Monday, May 21, 2018 7:38 AM

wjstix
Railroads pretty much used whatever worked.

Sometimes.  Depends on the railroad and what type of train.  I held two different jobs where I assigned engines to trains and there are patterns, it just might not be obvious.  Railroads classify engines differently than modelers or railfans and there are attributes that aren't necessarily visible to railfans that are very "visible" to the railroads.  

For example all the trains going through Fremont, NE, before the UP/CNW merger looked like a random mix of engines.  But the lead engine on every train was was a special sub-set of both railroad's fleets, units equipped with both the UP's cab signals and the CNW's ATC cab signals.

On the UP certain engines were "black listed" from being on intermodal trains due to their failure history.  Something that nobody but the railroad would know.

Dave H. Painted side goes up. My website : wnbranch.com

  • Member since
    January 2017
  • 2,980 posts
Posted by NWP SWP on Monday, May 21, 2018 10:11 AM

So if you were running a mix of GPs and SDs what units would be first?

Steve

If everything seems under control, you're not going fast enough!

  • Member since
    September 2003
  • From: Omaha, NE
  • 10,614 posts
Posted by dehusman on Monday, May 21, 2018 10:47 AM

Depends.  Why are you mixing GP's and SD's?  Are they both equipped the same?  What are the requirements for the route the train is traveling?

If everything is the same and there are no route restrictions then it doesn't matter.

If one unit has fuel or operating equipment (pace setter, dynamic brakes, Maxi-trac, etc) and the other doesn't, the one equipped leads.

If one has safety equipment (TIR, safety glazing, ditch lights, digital event recorder, rotary beacons, cab signals, PTC, etc) and the other doesn't, the one equipped leads.

If one has crew equipment (high backed seats, better control stand, air conditioning, toilet, 3 or more seats, on board computer, etc.) and the other doesn't, the one equipped leads.

If the GP's are being set out on line to swap local power, then the SD's lead.

 

 

Dave H. Painted side goes up. My website : wnbranch.com

  • Member since
    February 2002
  • From: Mpls/St.Paul
  • 13,771 posts
Posted by wjstix on Monday, May 21, 2018 11:34 AM

I think the answer the OP is looking for is more like "GPs are smaller than SDs, and the smaller engines always go in front" or something like that - which was true for steam doubleheaders (not helpers, doubleheaders) but not for diesels. I see CP and BNSF trains every day going to and from work, and I don't know that someone could find too much of a pattern. Larger, relatively newer type engines like SD-70s, AC-4400s, GEVOs and such often run together on long mainline freights, like oil trains going to and  from North Dakota. Otherwise, I often see GP38s and SD-40-2s (or similar engines) working together, occassionally with a newer larger engine. GEs and GM products are often together, doesn't seem to be a pattern as to which goes first or who works with who.

Stix
  • Member since
    September 2003
  • From: Omaha, NE
  • 10,614 posts
Posted by dehusman on Monday, May 21, 2018 12:22 PM

wjstix
I think the answer the OP is looking for is more like "GPs are smaller than SDs, and the smaller engines always go in front" or something like that

I think he will be disappointed.

Larger, relatively newer type engines like SD-70s, AC-4400s, GEVOs and such often run together on long mainline freights,

This harks back to my comment on the difference between a real and a model railroader.  The real railroads would consider all those engines essentially the same thing.  A real railroad sees high horsepower, 6 axle engines.

Otherwise, I often see GP38s and SD-40-2s (or similar engines) working together, occassionally with a newer larger engine.

Era and road dependent.  Today, both GP38s and SD40s are considered "yard" or "local" power, so are once again, pretty much the same thing.  40 years ago they were considered very different.

40 years ago engines were equipped for specific service (it was cheaper), now they are generally equipped with everything.  It used to be that certain engines had UP cab signals, certain engines had CNW cab signals, certain engines had CNW ATS, certain engines had UP and CNW cab signals, certain engines had CNW cab signals and ATS, and a few engines had all three.  Now most road engines come equipped with all three right out of the box, plus PTC.  Its now cheaper to equip everything and not have specialized pools.

Dave H. Painted side goes up. My website : wnbranch.com

  • Member since
    September 2008
  • 212 posts
Posted by NILE on Sunday, June 17, 2018 5:56 PM

This is a great thread.  Some much information about how the railroads used power together.  I model both 1st generation diesels and moden power.  What types of engines were rated for different speeds?  Was it as simple as passenger versus frieght locomotives?  Are frieght locomotives rated for different speeds?  Are modern locomotives rated differently, or are they purely horsepower? 

Thanks.

  • Member since
    April 2003
  • 305,205 posts
Posted by Anonymous on Sunday, June 17, 2018 6:56 PM

NWP SWP

Here's one such occasion.

Here's three Centennials and two other units on the lead of a train.

 

Top photo is SD45 with DD35.  Note the flared radiator at the back of the long hood on the lead unit. 

 

Bottom photo second unit back is UP 8057 a SD40-2 which was geared for 80mph service.  (Source Utah rails).  

http://utahrails.net/articles/up-fast-forties.php

 

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Users Online

There are no community member online

Search the Community

ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT
Model Railroader Newsletter See all
Sign up for our FREE e-newsletter and get model railroad news in your inbox!