F units & E units

[Murphy Siding]

     I read where a lot of railroads, when they saw that passenger business was in decline, opted to buy F7's instead of E7's, to use for passenger trains.  That way, the F7's could be diverted to freight service in the end.  If that's so, why did they bother to buy E7's at all?

[jrbernier]

Murph,

  I think you have data/info mixed up.  The E7 was produced from 1945 up through 1949.  The F7 was produced from 1949 through 1954.  The E7 was a dedicated 'passenger' engine.  Most F7's were sold for mainline freight service, although several Western roads like to use them as passenger engines due to mountain grades.

  By 1954, most locomotive purchasing was freight and the hood type units were what was being purchased.  Some dedicated passenger engines were still built through about 1961(EMD E9's).   Some roads(N&W) came late to dieselization and bought boiler equipped GP9's for passenger service.  By the mid 60's, any passenger engine needs were handled by existing power or boiler equipped SDP35/SDP40/SDP45 engines(that could be moved to freight service).

Jim

[MILW205]

Murph,

  I think you have data/info mixed up.  The E7 was produced from 1945 up through 1949.  The F7 was produced from 1949 through 1954.  The E7 was a dedicated 'passenger' engine.  Most F7's were sold for mainline freight service, although several Western roads like to use them as passenger engines due to mountain grades.

  By 1954, most locomotive purchasing was freight and the hood type units were what was being purchased.  Some dedicated passenger engines were still built through about 1961(EMD E9's).   Some roads(N&W) came late to dieselization and bought boiler equipped GP9's for passenger service.  By the mid 60's, any passenger engine needs were handled by existing power or boiler equipped SDP35/SDP40/SDP45 engines(that could be moved to freight service).

Jim

Additionally, this is not to say that the E's could not be used for freight.  Several railroads -- Erie Lackawanna, to name one (others have been discussed on the forum previously) -- used E's for freight service after their passenger-hauling days were over.

Meanwhile, EMD sold late-model F-units that were specifically intended for passenger duty, namely the FP7 and FP9, with the "P" signifying passenger.  The frames were 4' longer IIRC, allowing for more space for the boiler and water tank.

Finally, agree with Jim that most 1960's passenger duty-capable locos were the hood units mentioned, but I'd also like to note that EMD delivered cowled FP45 units to the Santa Fe and Milwaukee Road; both of which used them for freight duty after their more prestigious days of Super Chief and Hiawatha service were done.

[wjstix]

The "problem" if you will with E-units was that unlike SD's where all three axles in a truck are powered, the center truck on an E unit was an unpowered idler. So whereas an SD-9 is a "C-C" set up, an E-9 is an "A1A-A1A" arrangement. This was great for high speed flatland running, but caused problems when railroads tried to use them in the mountains (like Great Northern in Montana). F units had all axles powered and were able to haul the trains over the grades and still run very fast on flatland trackage.

[Paul Milenkovic]

The "streamline" or "lightweight" passenger car, the use of scare quotes because the were not that light and only somewhat streamlined, essentially the Amtrak Heritage Fleet: the AAR roof profile, two-axle swing-motion, pedestal journal guide trucks, air conditioned with non-opening windows, along with the matching cab-type locomotive is essentially a product of the 1930s, the 1941-45 WW-II years putting a lot of the streamline-Diesel transition on hold, with what I see has a mass Dieselization and adoption of the lightweight passenger car post war into the early 1950s.  The dates and production quantities in the various Diesel Spotter's Guides are a good resource on when this all happened.

The E-7 was the biggie as far as post WW-II passenger Dieselization, followed by the E-8 for roads wanting more HP per unit and passenger-geared F-7 for mountain roads needing more weight on drivers.  The big purchases of these locomotives and passenger cars must have been in the 1945-1952 time frame.

What happened is that while the railroads were swamped with passenger and other traffic during WW-II owing to troop movements and gas and airline flight rationing, and while the railroads sunk a lot of money replacing their passenger fleet with Diesels and lightweight streamline passenger cars after WW-II, the travelling public deserted the rails and left the railroads holding the bag.  A lot of this happened or started happening before a lot of the Interstate even got into high gear or before the development of the DC-9 and B-727 jets for domestic service.

By the early to mid 1950s, the pickle that passenger service was in became apparent, and the acquisition of passenger equipment and motive power essentially came to a halt.  There were the odd exceptions -- the Sante Fe High Level fleet was acquired, what, late 1950s?  C&NW acquired long-distance versions of their commuter bilevels in the same time frame.

The "lightweight experimentals" -- the post WW-II bi-directional Talgo on the New Haven, Boston and Maine, and Rock Island, that bus-bodied GM Aerotrain, the Robert Young inspired Train-X, the low-roofed locomotive-nosed New Haven RDC's marketed as "RDC Hot Rod", the Budd-Pennsy "Tubular Train" had their debut in the mid to late 1950s, and all of this ill-fated, ill-received effort was long past the major acquisitions of conventional streamline cars and locomotives.  The "lightweight experimentals", failures as they are perceived, were the last efforts at improved passenger tech that didn't have some kind of Federal government involvement.

By the late 50's, early 60's, the first-generation passenger Diesels started wearing out as Diesels do in high mileage service.  The replacements, as indicated, were a smattering of things -- late model E9's, the passenger-geared steam-generator equiped SDP-35 (SCL), SDP-40 (GN), and SDP-45 (SP) along with the GE U28C (Santa Fe) (see the Diesel Spotter's guide for clarification on the roads) provided 6-axle high-horsepower hood units for passenger service, followed by the FP-45 (Santa Fe, Milwaukee Road) and U30-CG cowl units (Santa Fe).  Those latter-day passenger units were very low-volume production because passenger service was on the way out and down, and the railroads were not keeping up a dying part of their business.

When Amtrak inherited what was left of passenger service, the FP-45s were fine, but they were few in number, and the railroads were most keen on keeping the workable FP-45s and handing of junker cab units on Amtrak, hence the conversion to freight service of perfectly servicable passenger power.  It is not clear, however, how suited the big C-C's were to high-speed passenger service -- I saw some remark that Milwaukee Road developed a preference to run their FP-45's trailing cab units on account of concerns of smooth tracking.  Of course Amtrak jumped in with both feet with the SDP-40F purchase because 6-axle cowl units is what the railroads were buying if they were buying any replacement passenger power at all, and those got retired early, and so on.

[blue streak 1]

Southern RR by 1954 (end of steam operations) was still short of passenger diesels and was using some E-6,7.8.9s ,FP7s, GP-7s, PA-4s, and some Alcoa rs-?+ some F-7s and Heater Cars attached to freight units to fill in when passenger units failed. In two years; train offs and reduction of consists allowed all of the oddballs to be retired or turned to freight service and Es were used almost exclusively except maybe Ashville, NC trains.

[Murphy Siding]

Murph,

  I think you have data/info mixed up.  The E7 was produced from 1945 up through 1949.  The F7 was produced from 1949 through 1954. 

Jim

You're correct, in my haste I picked E7 and F7 thinking of them as contemporaries.  I think it was the F7's and GP7's that were built about the same time.  I just didn't understand why a railroad wouldn't buy the more universal F's over the E's?

[daveklepper]

The B&M wanted to dieselize, but during WWII only freight locomotives could be built, with fuew exceptions.   So it got FT's, then a few interim F2's, and then F3's.  None built with boilers.  But the B&M did put boilers in some FT B-units (where there was room) and used them in instensive passenger service where diesel fuel was already available because of an existing diesel switcher fleet.  They had considerable experience with F-Type EMD products during WWII.   Still, when passenger locomotive production was restored, they did buy a few E-units, several E-7's over the yeas, with the last delivered as the single E-8, and these were assigned only to Boston - Portland, with a few running through over the Maine Central to Bangor, a very flat route where one E could handle up to 12 cars, and for running opposite the Canadian Pacific's E units (only two) on the relatively short consist Alouette and Red Wing, day and night Boston - Montreal.   Nearly all other passenger assignments were handled by the boiler-equipped F's, and then the Alco and GP-7 road-switchers, also boiler equpped.   GP-7's 1567 or 1568, in autumn 1952 and in 1953 regularly handled the 4pm Boston - Portsmouth local and returned handling a frieght with one set-out an pick-up.   Budd RDC's and train-offs ended all of this, exept the freight. 

[trainfan1221]

The GP7 and F7 were contemporaries.  The E7 was replaced by the E8 and then E9 models.   As mentioned most regular road units could be equipped to pull passenger trains.  Over here on NJTransit we have the original GP40p units (rebuilt somewhat) running in regular service everyday.   Then of course there were the U34CH engines which were built for both services for EL, though use on freight was scarce I believe.  I would guess the SDP40f was EMD's first venture back into actual passenger units after the original E units.   Of course, as we all know, it didn't end too well there.

[CNW 6000]

Not to ask the stupid question, but I know nothing about passenger stuff.

Why was a boiler/water tank needed?

[Steve_F]

To put it simply, when steam was king passenger trains were heated by steam from the locomotive, when diesels came along rather than change entire passenger fleets to another form of heating they just added steam to the diesels. In some cases where there were no steam equipped diesels available steam vans were used, basically a car with a steam generator (diesel boiler) coupled behind the locomotive(s).

[wjstix]

Steam was sometimes used by the dining car for cooking / heating. Some passenger cars even used steam air conditioning!!

[CSSHEGEWISCH]

Steam was sometimes used by the dining car for cooking / heating. Some passenger cars even used steam air conditioning!!

ATSF was a major user of steam ejector air conditioning in its streamlined equipment, I'm not sure about other roads.

[Paul Milenkovic]

In case people are wondering how hot steam can make cool air conditioned air, a steam ejector is simply a nozzle that uses a jet of steam to pull a draft.  The good ol' steam locomotive uses a steam ejector from the cylinder exhaust to pull a draft through the flues and firebox.  Why even the United Aircraft TurboTrain used a turbine exhaust ejector -- those fat stacks out the top of the Dome Car -- to ventilate the engine and accessory compartment without requiring fans.

In steam ejector air conditioning, the steam ejector nozzle pulls a vacuum so that water can boil at a vacuum, and water boiling at a vacuum provides the chill.  Like the steam locomotive, the steam ejector air conditioner may not be particularly thermally efficient, but it is a simple and elegant solution when you have a lot of steam.

Closed-cycle refrigeration using ammonia as a working fluid is common in commercial refrigeration; someone could weigh in on whether steam ejectors are used for chilled water supply for airconditioning using district HVAC systems.  I suspect they are because the central steam plant where I work at the U also provides chilled water for summer AC, but I never got to take the tour of that plant I had organized for some Korean visitors because they wanted to see a power generation plant and not a district heating plant.

Steam lines on passenger trains have gotten a bad rap or rep, and the between-car steam connection may be problematic, Diesel generator HEP sets may be more reliable than steam boilers, and steam has distribution problems above a certain train length.  But steam heat must be more energy efficient than electric heat off an HEP genset, and steam heat is widely used to this day in district heating -- where I work, we don't run a Diesel genset in a neighboring building to feed resistance grid baseboards in a classroom.

Steam ejector AC was particularly problematic in the early Amtrak days when they mixed and matched Heritage Fleet equipment around the network.  There was something in Trains about how SP crews didn't know why they had to attend to train boiler alarms in summer, and passengers riding in Santa Fe coaches on that run sweltered.  Also, the AC needed a lot of steam, and for AC, Diesel gensets and electric-driven AC compressors is much more energy efficient than a locomotive "steam generator" and that AC ejector system.

[ndbprr]

Not all railroads had e units either.  ATSF and GN come to mind and there was a reason for that.  E units were designed to replace 4-4-2 and 4-6-2 steam engines which were (for the most part) speed engines rather than tonnage engines.  E units could not handle long sustained grades very well at all.  F units were much better since all the weight was on the drivers. The only railroad that had a fleet of E units that had a serious grade was the PRR and that was up horseshoe curve out of Altoona for seven miles.  Since helpers were on every train any way that was not a problem.  The six wheel truck for the E unit gave a phenomenal ride but they were for flat land running not pulling grades.

[CSSHEGEWISCH]

ATSF and GN each had small fleets of E's.  E1's were the power for the first streamlined Super Chief, and ATSF also had a handful of E3's and E6's.  The E1's were later rebuilt into E8's.  On ATSF, the various E's were overwhelmed in numbers by passenger F's and Alco PA's.

On GN, the first streamlined Empire Builder had E7A's assigned, they were later bumped to secondary trains out of the Twin Cities.

[oltmannd]

The choice was basically between a 2000 HP locomotive and a 1500 HP locomotive. Both had 4 powered axles and with similar gearing, each could take the same tonnage up a specified grade.  (The F's had somewhat higher #/axle, making them a bit more capable on grades, perhaps)  So the choice comes down to the application and use.  How much HP per ton do you need for the schedule you want to keep and how many units of each, at what cost to buy and maintain, would it take?  Lowest $$ wins!

[beaulieu]

Another point is that the F-units weren't good at speeds above 80 mph, too much truck hunting. The E-units with the long wheelbase performed better.

[oltmannd]

Another point is that the F-units weren't good at speeds above 80 mph, too much truck hunting. The E-units with the long wheelbase performed better.

Not sure truck hunting was much of an issue before welded rail....

[WSOR 3801]

Another point is that the F-units weren't good at speeds above 80 mph, too much truck hunting. The E-units with the long wheelbase performed better.

ATSF used to run F-units in the triple digits.  Maybe their track was better.  They also had no problems with SDP40Fs, even buying some after they were banned from other lines. 

 

[wjstix]

Most railroads were limited to 79 MPH, above that you had to have in-cab signalling or some other safety devices that most railroads didn't want to pay for. But ATSF usually did have very well maintained track, I know they didn't have trouble with their RSD-4/5 models the way some other railroads did...apparently because of their superior trackage.

BTW I rode behind a GN E-unit on the Badger (Twin Cities - Superior WI) in 1969.

[blue streak 1]

in the late 40s and early 50s SOU had ATS installed in the passenger E's and F's and some freight F's but rapidly removed the systems. Used same trackside equipment that is still on the LAX - SAN surf line.

[rrboomer]

The extra 4' truck centers of the FP7 is an altogether different (meaning better) ride than a regular F unit. The Rock Island had three high speed FP's and I've ridden them at the century mark on stick and welded rail, no hunting.

However, a regular F unit with the 30' truck centers plus 9' truck wheelbase equates to two wheels on each side on a rail joint at the same time when riding on 39' stick rail. If the railroad is "Low joints and high centers" you will feel it.  The FP7 will glide right over that same track.

Another plus for the F/FP is that a 102 mph gearing has a minimum continuous speed of aprox (my books are still packed away) 13.5 mph and the E unit's min cont. speed is aprox 25 mph. That kind of tells the tale why the ATSF, GN, NP, CP, CN nd SOO used F units (+geeps) on most or all of their long haul trains.

[YoHo1975]

As a point of Clarification, EMD built the FP45s for passenger service on the Santa Fe in 1967 BEFORE they built the SDFP40s for Amtrack in 1973.

 

The last E9 rolled off the line in 1963 and the last F unit in 1960.

 

So there was only a very short period where they didn't have purpose built passenger units and that ignores the hood unit passenger units like the SDP40 which was built in between.  

[zardoz]

Another point is that the F-units weren't good at speeds above 80 mph, too much truck hunting. The E-units with the long wheelbase performed better.

Not sure truck hunting was much of an issue before welded rail....

"Hunting" was horrible on F units, especially on jointed rail.  The C&NW had old 39' stick rail from Waukegan to Kenosha, and the suburban trains ran at 70mph.  We would swear sometimes that we were going to topple the rails due to the trucks banging the rails so severely.  Most engineers would keep the speed down to 60 or so due to the condition.  Riding in the E units was like riding on soft cushions (at least compared to F units).

[Murphy Siding]

     ? Was the rough ride due to the 39' stick rail in relationship to the center to center measure on the trucks themselves, or the center to center measure on the axles on each truck?

[rrboomer]

  

 Murphy Siding wrote the following post at 06-12-2008 8:56 PM:

     ? Was the rough ride due to the 39' stick rail in relationship to the center to center measure on the trucks themselves, or the center to center measure on the axles on each truck?

Truck center to truck center is 30'.  Each truck has a 9' wheelbase. These measurements equate to the front and rear wheel on the right side being on a rail joint at the same moment which then shifts to the left side as the front and rear wheel pass over the joint at each end of the 39' rail. Plus the rear wheel of the front truck and front wheel of rear truck also pass over the rail joint, but not at the same time as they are only 21' apart. At 60 mph this all happens about twice per second.  So if there are low or battered joints you can imagine the near twisting motion that's going on under the locomotive. Eventually all this wear seems to tend to elongate truck center casting, which adds lateral motion to the mix.  As you are going down the railroad hanging on to the seat and brake valve for dear life and listening the the beating the side bearings are taking, you tend to wonder how it all holds together.

The 30' truck center was one of EMD's "Goofs" IMHO, but when it was designed the stick rail was maintained to much higher standards.

[Murphy Siding]

     Did the GP7/9/etc... have the same wheelbases, and the same issues?

[rrboomer]

GP7/9/18 has 31' truck centers and ride better than the 30' F unit on rough jointed rail. Don't know what the BL-2 truck centers were.

EMD inadvertently gave the GP7/9/18 a built in branch line speedometer with the 31' centers. When the unit started into a hippity-hop motion, it was telling you "Fast enough".  Confirming the speed with a watch check usually showed you were going just a couple of miles over the posted limit.

 

[Railway Man]

I have never experienced a bad ride in an F7 and F9 that was any worse than a GP40, SD45 or SD40 on the same track, and I have lots of mileage on 39' stick rail.  I always thought the Fs rode quite nicely, especially compared to a GP40, which can be pretty bouncy, the worst being the wide-nose CN locomotives because they're nose heavy.  The difference may be in the truck maintenance standards at different railroads.  The outside swing-hanger truck has lots and lots of wear points.  Most of my mileage back when F units were still running was on western roads that had a lot of money and kept after their power -- so much so that when we saw anything but clear exhaust from a GP or F at full load we wondered what was wrong with it.  I have always appreciated the way an SD45 or SD40 will just float through a rough spot while the next day on an AC4400 at the same place it feels like it's derailed already.

RWM