It was also pretty common on the Kansas City Southern and the Spokane, Portland and Seattle.
Although I think you are speaking to EMD units, D&RGW had ALCO PAs MUd to EMD F-units on their Yampa Valley Mail.
RicZ
tstage So, would the EMD E- and passenger F-units have been geared exactly the same? Tom
So, would the EMD E- and passenger F-units have been geared exactly the same?
Tom
As far as I know, that's the way it was with the B&O F3 AB sets.
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
C&NW/Omaha Road often used an E and an F-unit together on their Chicago - Duluth/Superior overnight train, apparently with the E usually in the lead. That train often carried more mail cars than 'regular' passenger cars, so the F may have been added when the train was especially long. I've seen pics where the F-unit was in freight colors, so they may have had F-units with pass-through piping to allow steam to go from the E-unit to the cars behind.
B&O bought seven AB F3 sets with passenger gearing and steam generators in 1947, and posed them in press photos of the road's new all-coach Washington-Chicago "Columbian" streamliner. Most of the cars for that train have been released by Walthers in the past year or so. However, in actual practice, the "Columbian" usually operated behind E units. Assignments in the early 1950's are explained in A Picture History of B&O Motive Power, by Lawrence W. Sagle, 1952. The 14 F3 A or B units were usually operated in 3 unit sets on the "Capitol Limited" (Washington-Chicago) or the "Ambassador" (Washington-Detroit), with the two spare units being available for the general passenger pool.
But here's the unusual wrinkle: The "Capitol" often was photographed operating with an E unit in the lead, with an F3 B and A unit trailing. It has been suggested that this was done in response to requests by Capitol Limited engine crews, who preferred the ride of an E at speed. It can probably be presumed that the spare F3 units in the general passenger pool would sometimes operate with E's. Eventually, B&O acquired enough E units to cover all mainline passenger assignments, so in 1957, the F3's were reassigned to freight service, although I think they retained their passenger gearing and steam generators. This made them available for excursions or emergency power substitutions, in common with several other B&O freight cab units that were so equipped. After reassignment to freight service, these matched sets generally remained together, probably because of their higher gearing.
In short, they should operate fine, especally if the gearing is matched, as on these B&O units.
(edited Sunday morning)
Freight units tended to be geared for about 65 mph max. Passenger a good bit faster. And diesels geared for different top speeds ran inefficiently together. So, whatcha wanna look for is railroads that had both E's and F's in passenger service and see if they mixed them.
Santa Fe had lotsa passenger F's and also some passenger E's.
UP had lotsa passenger E's and some passenger F's. I'm looking at a photo of an E7A trailed by an F7B.
I HAVE seen out of the Twin Cities some GN passenger F's mixed in with the E7A's.
And note that both your E's and F's will have steam generators. With the possible exception of putting one or two generator-less units AT THE FRONT. But there weren't too many high speed E's and F's without generators. If any.
Ed
Yes I can remember seeing some Chicago & North Western passenger trains on the "old line" from Chicago to Milwaukee in the mid to late 1960s that were pulled by an E unit/F unit (possibly an FP7) mix. My hunch is it might have been the Flambeau 400 when it was swollen with extra cars during the summer vacation periods. Most C&NW passenger trains that I saw were pulled by a single unit, either F or E.
Dave Nelson
There seems to be only a few internet pics of E units and F units MU'ed together on trains. I know they were purposed for different things, but there were F units in passenger service. Did the units not work well together, did the railroads care about how it "looked"? I have some matching Fs and Es for my model railroad and want to run them together, but that does not to seem normal.