mixed a and b units

Discussion in 'FAQs' started by Collyn, Jan 17, 2007.

  1. Collyn

    Collyn Member

    is it a comon practice to use b units that differ from the a unit. Do the always use an F7 B unit with an F7 A unit?
  2. green_elite_cab

    green_elite_cab Keep It Moving!

    In earlier F units like the FT, they were semi permanently coupled, so no, atleast as far as early diesels go. as you move on in years, i don't know. F7and 9s may have been mixed, but i haven't noticed either way.
  3. LongIslandTom

    LongIslandTom Member

    I don't know about the olden times, but modern day B-units are often mixed into consists with different loco types...

    For example, I've seen Bunsuf's cabless GP60B's mixed into consists of SD70MACs or C44-9Ws, etc.
  4. Russ Bellinis

    Russ Bellinis Active Member

    The ft's were originally permanantly coupled units, but eventually the Santa Fe modified theirs to make them separate units. From the f3 and f7 on they were separate units, the Santa Fe originally numbered theirs as sets, but with in a few years they realised that if they were kept as sets, then a breakdown on one b unit put four units out of service. At that point they were renumbered and the Santa Fe used them indiscriminantely. The only caveat was that they had different gearing for passenger service engines (red & silver warbonnett) and freight units which were blue and yellow. They also had some set up as dual purpose with an intermediate gearing I think. I think they had to be careful about mixing locomotives that were not geared the same. Other wise they pretty much mixed things up as needed, including running gp7's & gp9's in the mix with the f units.
  5. kitsune

    kitsune Member

  6. liven_letdie

    liven_letdie Member

    Hey Russ,

    Good info, and put in a way I can understand! One question, I think I have seen pictures of freight equipment having to pull a passenger train in a pinch but did it ever go the other way around? Would they have sufficient gearing etc without blowing up the traction motors? One more question too, did it make a difference to mix freight units between different roadnames, specifically the FT's during a merger?

  7. Triplex

    Triplex Active Member

    Passenger equipment was sometimes pressed into freight service. Several railroads used old E-units on fast freights. They usually ended up wearing out the traction motors quickly.

    If you're modelling the transition era, diesels more often (but certainly not always) ran in kind. Aside from the FT, I don't know if any mainline diesel was drawbar-coupled, at least as a standard feature. In the 60s and 70s, anything under the sun would run together. On this thread http://www.the-gauge.com/showthread.php?t=24541 there are a lot of odd lashups.

    Some railroads had B-units of types where they didn't have the corresponding A-unit. GN had F9Bs but no F9As; they were intended to run with F7As. SP had DD35s (which, despite the lack of a B in the designation, were cabless) but no DD35As.
    "Often" is relative, as there aren't too many B-units left. The GP60Bs are the largest group remaining since BNSF retired their ex-BN cabless B30-7As. (Incidentally, those were another type of engine where the owning railroad didn't have the corresponding A-unit.)
  8. 60103

    60103 Pooh Bah

    Once you get past the initial confusion, most units could be mixed; I'm not sure how they adapt for different gearings but I have seen a long lashup on CN that mixed CCs, BBs and even switchers. I think even the kitchen sink was pulling in that one.
    VIA bought mostly FP7 and FP9 A units, F9B, FPA-2 and -4, FPB-2 and -4, and one RS10.* I've seen the RS10 in a set with an A and a ? .(wish I had taken more notes).
    "I know VIA bought other things.
    Interestingly, I haven't seen any of the latest purchases mixed. The Canadian usually gets a brace of F40PH, while the local trains seem to have a single P42DC. I never saw the LRC mated with anything and if they need two, they went on opposite ends of the train.
  9. kitsune

    kitsune Member

    David, regarding the LRCs, they used to be hauled by matching power units that were powered by Alco 251 blocks. Essentailly an FPA4 mechanical sucessor in a body that matched the LRC.
  10. Russ Bellinis

    Russ Bellinis Active Member

    I think most of it had to do with gearing. Also, I don't know about other roads, but Santa Fe had some blue & yellow units with steam generators in the b-units that they used in whatever way was needed. I don't think I've ever seen a picture of a blue & yellow freight scheme locomotive running in consist with a red & silver unit. I have seen pics of steam generator equipped gp7's or 9's running in consist with f-units. Also the Santa Fe had converted some tenders from steam engines into steam generator cars in case they had to use freight f-units to cover passenger trains so that they would have the steam available for heating and a/c.
  11. Triplex

    Triplex Active Member

    I think I have, from the early 70s after Amtrak took over passenger service and ATSF's red and silver engines were reassigned to freight.
  12. railohio

    railohio Active Member

    The Erie Lackawanna is famous for using passenger units in freight service, some re-geared and others not. This includes EMD E-units and Alco PAs, originally used in passenger service but which spent their last years working freight runs. The E-units were commonly seen on the west end of the system operating from Meadville to Hammond and down the Dayton branch. The Alco PAs were famously used on seasonal Cleveland to Youngstown ore trains where they replaced six-axle Baldwins in the late 1960s. The Erie Lackawanna also rostered thirty-three SDP35s, delivered in 1969, for freight service. These units were acquired for thier excessive fuel capacity and were never intended for passenger service.
  13. Russ Bellinis

    Russ Bellinis Active Member

    That is correct for Santa Fe's freight service. Even when they painted up equipment in the 1980's in the red and silve for the "super fleet", they announced that dispatchers would not be allowed to mix red & silver units with blue & yellow units. I think that edict lasted almost 24 hours before dispatchers started mixing them up in order to get enough power to run the trains at the speeds they wanted to run.

    I've never sen any pictures of Santa Fe mixing red & silver and blue & yellow or zebra stripes on passenger trains. The one exception being some of the Del Mar specials that they used to run on the Surf Line during the racing season at Del Mar. I think I've seen photos of zebra stripe gp7's or 9's coupled to blue & yellow f units.
  14. Triplex

    Triplex Active Member

    SDP45s - it was ACL, SAL, L&N and UP that owned SD35s.

    http://railpictures.net/viewphoto.php?id=70724 Here's an example of blue/yellow and silver/red engines on the Super C.
    http://railpictures.net/viewphoto.php?id=50095 And a couple silver/red B-units among these engines.
    I think I have...

    EDIT: And here's an example. http://www.railpictures.net/viewphoto.php?id=70715 Not on a passenger train esactly, but coupled to a baggage car, so they were presumably on a passenger train. Santa Fe's F45s didn't have steam generators - that was what FP45s were for - but they did have steam pass-through hoses so they could run behind passenger engines on passenger trains, as seen here.
  15. railohio

    railohio Active Member

    Yes, yes, Triplex got me. That's what happens when you're typing while doing homework.
  16. absnut

    absnut Member

    The Boston and Maine RR commonly ran FT-A/B+F2,F3, or F7 3 unit lash-ups. I believe (if my memory is still valid) I can remember seeing 4 unit lash-ups of FT-A/B+F3B+F3A (possibly F2A). In the case of some railroads, if you can imagine it, it might have been done.

    When the Bangor and Aroostook RR discontinued passenger service, they regeared their two E7's to run in freight service.... again, frequently seen running with the likes of F3's, BL2's, and Geeps in the same train. My understanding is that the B&A (BAR) shops performed this conversion for a few other railroads. Imagine it.... then do it!:thumb:

  17. Greg Elems

    Greg Elems Member

    WP routinely ran FTA/B-F3A lash ups. The Zephyr ran with FP7- F7B- F3B or two F7B's or two F3B's. Also WP ran their last four F7A's with just about any other engine on the railroad. They hauled switch engines to Oakland from Stockton and back with anything that was serviced and ready to go. Mix and match all you want, because it probably happened some where some time. :D

  18. Russ Bellinis

    Russ Bellinis Active Member

    I guess I wasn't as clear as I thought I was being. I was talking about a time when Santa Fe would run F units A's & B's, Gp7's & 9's & sometimes steam tenders converted to steam generator use. By the time the F45's and Fp 45's came on the scene, the f7's were on there way to becoming cf7's. Most b units were gone, and the whole passenger scene had changed completely. I was addressing the question of mixing and matching a & b units when they were still running a & b units, and I don't count Gp60's because they were not built until after Santa Fe got out of the passenger business and turned their passenger equipment over to Amtrak. In other words Fp45's are 10 years too new to count.
  19. Triplex

    Triplex Active Member

    http://www.railpictures.net/viewphoto.php?id=103957 Here's a mixed-color consist definitely on a passenger train. Silver/red FP45, blue/yellow "billboard" F45, silver/red F-unit.
    Actually, the cowls arrived in 1967-68. CF7 production didn't begin until 1970. I've seen lots of photos of F-units, both As and Bs, in the early 70s. In fact, mixed consists of early GPs and Fs were still found at that time.

    http://www.railpictures.net/viewphoto.php?id=53784 Three GPs and six F-units, one in silver (though I can't tell if it's silver/red, silver/yellow or silver/blue). 1972.

    http://www.railpictures.net/viewphoto.php?id=55150 Four F-units, two GPs... and is that first car an old steam tender? 1971.
  20. Russ Bellinis

    Russ Bellinis Active Member

    Your fiirst link is identified in the picture as pulling Amtrak #3, I'm not sure that those engines are on the Santa Fe at the time. At any rate it is not a Santa Fe train. I think Amtrak got some of the Santa Fe Fp45's in the early days before they started having derailing problems with them and sold them back to Santa Fe. The picture with the silver f unit ( I think I saw traces of red) is dated 1972, so it was probably taken after Santa Fe had turned the passenger business over to Amtrak and before they got all of the red & silver F3'3 & 7's into the shop to remove the steam generators & repaint and regear for freight service. On the last picture, the that does look like a steam engine tender. The date on the picture is 1971, so steam was definately long gone from the Santa Fe and the restoration of 3751 was still quite a few years into the future, so it was probably a steam generator car unless they used old tenders for other things as well. From the time the Gp7's & 9's arrived they were regularly mixed with blue & yellow freight F units in freight service. I still haven't seen any evidence that the Santa Fe intermixed red & silver F units with blue & yellow units or Gp 7's or 9's during the 1950's-1960's. During the early 1970's Amtrak was being formed and the Santa Fe waffled until the last minute debating on whether to continue their own passenger service or join Amtrak, and finally near the last minute decided to drop passenger service and join turn it over to Amtrak.

Share This Page