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Next question: related to EMD E and F
Posted by DPool on Wednesday, January 23, 2019 11:24 AM

I already alluded to childhood passions for pre-Amtrak passenger service...my mother was a fearful flyer and, as a result, until 1969 if we didn't drive across the country (CA>NC>CA), we took the train. And that's when/how repeated trips on the City of Los Angeles, the Sunset Limited, the California Zephyr, the B&O Capitol Limited and the Seaboard Silver Meteor anchored the image of the EMD E and F series as the "standard" locomotive of streamliner passenger service. I've never been able to really tell the difference between the E and the F (was the E longer?) and as far as I've ever been able to tell, they shared the same bulldog nose. However, I *have* noted that some of them (most?) had a roof section that ran in an unbroken arch from side to side (was this the "Conestoga roof"?) while others had a narrower roof section that connected two angled panels that ran most of the length of the unit at 45-degrees to the sides (hope that's clear). Was this any kind of identifier for any of the various E and F series?

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Posted by Flintlock76 on Wednesday, January 23, 2019 11:47 AM

Oh boy, this can get complicated.

Simply put, the "F" units were freight engines, although they could be custom modified for passenger use, and the "E" units were passenger units.  The easiest way to tell the difference is the "E" units were twin-engined, so they were longer than the "F" units.

During the production runs from the late 30's through the end there were some external differences in body styles of both types, but too many to go into here.  You'd have to check a reference work like "The Diesel Spotters Guide" to see them all.

The "F" in F-unit stood for "freight," the "E" in E-unit stood for "Eighteen-hundred horsepower," the power rating for the original units.  Horsepower was upped in later models, but the "E" designator was retained.

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Posted by timz on Wednesday, January 23, 2019 12:50 PM

E-units were never intended to pull anything but passenger/mail trains; each one had two 12-cylinder engines and 12 wheels. Until 1945 they all had noses sloped 60? degrees to horizontal, after that they were all 70? degrees. They were 20 feet longer than most F-units.

F-units had one 16-cyl engine and 8 wheels, and always had the 70-degree nose.

All your City of LA trips were behind Union Pacific E-units.

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Posted by DPool on Wednesday, January 23, 2019 1:20 PM

Aha! I'd noticed the difference in the "nose slope" and always just assumed (see that?) this was due to unique specs of a particular RR customer. Thanks for that info, timz!

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Posted by Erik_Mag on Wednesday, January 23, 2019 2:21 PM

Pre-war EMD locomotive models were often derived from the engine power available, with "S" being Six hundred HP, "N" being Nine hundred HP, "E" for Eighteen hundred HP (back in the 12 cyl Winton 201A days) and "F" was for Fourteen hunndred HP (1350HP for the FT).

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Posted by Deggesty on Thursday, January 24, 2019 11:08 AM

As to the number of wheels on the locomotives described, each truck, whether four-wheeled ot six-wheeled, had two driven axles.The middle axle on the six-wheeled truck was not powered, but was there for weight distribution, since the second diesel engine inside added more weight than a four-wheel truck could safely bear and distribute along the track.

Letters and numerals were used o describe the truck; letters indicated powered axles and numerals indicated unpowered axles. Thus a locomotive with two four-wheeled trucks was a B-B, and one with two six-wheeled trucks was an A-1-A A-1-A..

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Posted by Overmod on Thursday, January 24, 2019 2:38 PM

DPool
I've never been able to really tell the difference between the E and the F (was the E longer?) and as far as I've ever been able to tell, they shared the same bulldog nose.

The early E units, through E6, were built with the long 'slant nose'.  The first E unit with bulldog nose was the E7 (which was the 'breakout' locomotive for EMD, with so many produced for postwar streamliner dieselization) -- but this is not quite the same nose as the F unit; in particular, it wasn't uncommon for E7s to retain passenger-style pilots (often with retractable couplers, if I remember correctly) instead of using the F style (with the rolled-under panel beneath the front anticlimber)

The E8 mitigated some of the 'freightization' of the E7 by providing those flush curved glass numberboards on most examples.  E9 is basically distinguished more by the horsepower increase (and some betterment of the systems achieving it) than by major external or design changes.

Note that there were F units used in high-speed service, notably on ATSF (which, in fact, used them in favor of E units on most of its traffic).  That's another indication that the 'Blomberg' A-1-A truck was more for weight accommodation (in the longer carbody required for two V12s and generators to 'make the horsepower') than for higher running stability.  It can be argued (and has been argued, but I don't remember the sources) that the B swing-hanger truck is more stable at high speed than the A-1-A.

 

However, I *have* noted that some of them (most?) had a roof section that ran in an unbroken arch from side to side (was this the "Conestoga roof"?) while others had a narrower roof section that connected two angled panels that ran most of the length of the unit at 45-degrees to the sides (hope that's clear).

Are you SURE that you're not channelling those late Australian locomotives (we've just succeeded in preserving one example; look up 'The Last Streamliner' on GoFundMe) that essentially used an FP45-style 'cowl' carbody with a bulldog EMD nose?

I don't think most railfans really consider things like the F40 or F45 to be 'follow-ons' to the F-unit series.  If you do, I think the spotting difference of the angular nose is far more distinctive than the angularity of the roof panels, radiator arrangement, etc.

Of course, the use of angled upper carbody sides with an arched roof between them is a Baldwin trait (see any Sharknose, passenger or freight)...

Was this any kind of identifier for any of the various E and F series?

For what may be regrettable politically-correct reasons of a sort, none of the cowls were called "E units" even if used in passenger service -- they were given the FP designation (P for 'passenger') to designate that they could be used in dual-service or continue as freight power if passenger trains 'went away'.  For better or worse this was a reason for Amtrak buying "SDP40Fs" as their first replacement power order (and the 'Pooch' P30CHs a bit later): if Amtrak were to fail, the Government wouldn't be stuck with difficult-to-peddle dedicated light passenger engines (what was that early EMD alternative, the AMT125?)  I don't know if the trend away from cowl units for general freight service was already becoming established by then, but neither the GE nor the EMD cowl units had a particularly long, or wide, era as first-line design alternative.  (That was particularly regrettable in the case of the ATSF GEs, which I thought were 'less unstreamlined' than any of the F or FP engines; and I do confess that, even knowing what an operating disaster it would have likely been, I'm sorry Alco never built a C636P with those fascinating trucks.)

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Posted by zardoz on Saturday, January 26, 2019 12:58 PM

Overmod
Note that there were F units used in high-speed service, notably on ATSF (which, in fact, used them in favor of E units on most of its traffic).  That's another indication that the 'Blomberg' A-1-A truck was more for weight accommodation (in the longer carbody required for two V12s and generators to 'make the horsepower') than for higher running stability.  It can be argued (and has been argued, but I don't remember the sources) that the B swing-hanger truck is more stable at high speed than the A-1-A.

Those ATSF F units must have had a great truck design; either that, or the roadbed was incredibly smooth.

In CNW-Metra passenger service, we used both F and E units. The difference in ride quality on stick rail was literaly night-and-day. I will admit I do not know what a "B swing hanger truck" is, nor what difference it would make.

For all of my career at CNW, the track north of Waukegan was all 39' jointed rail. When those F7s got to about 50mph, the trucks would start slaming side-to-side as well as bouncing over the rail joints, with the slamming increasing as the speed increased. Some the old heads, even those with years of steam experience, would balk at riding on the F7's up to 70mph. It was a scary ride, at least on par with the rock-n-roll of the SD45 on old jointed rail.

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Posted by Flintlock76 on Sunday, January 27, 2019 9:24 AM

I read somewhere that the ATSF preferred the F units for passenger work because of the four wheel trucks.  With the weight of the locomotive concentrated on four wheel and not six wheel trucks the F units were more sure-footed on all those hills the ATSF had to climb.  

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Posted by Erik_Mag on Sunday, January 27, 2019 10:42 PM

With the ruling grade of 3% on Raton Pass, the AT&SF would most certainly be looking at passenger power that would be good for extended periods of hih tractive effort. The 6 wheel Blombergs on the E's were only good for 36" wheels, while the  wheel Blombergs used on the F's were fitted with 40" wheels. This mean that a larger traction motor could be fitted in the 4 wheel Blombergs, which less of a risk of traction motor burnout on Raton Pass.

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Posted by SD70Dude on Sunday, January 27, 2019 10:47 PM

Erik_Mag

With the ruling grade of 3% on Raton Pass, the AT&SF would most certainly be looking at passenger power that would be good for extended periods of hih tractive effort. The 6 wheel Blombergs on the E's were only good for 36" wheels, while the  wheel Blombergs used on the F's were fitted with 40" wheels. This mean that a larger traction motor could be fitted in the 4 wheel Blombergs, which less of a risk of traction motor burnout on Raton Pass.

On another thread someone mentioned a "ALCO curve" on one of ATSF's passes, supposedly named after a passenger train with A1A units had stalled there.  

Could this incident have occurred on the same trip where the DL-109's literally melted some traction motors?

Greetings from Alberta

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Posted by Overmod on Monday, January 28, 2019 10:10 AM

SD70Dude
On another thread someone mentioned a "ALCO curve" on one of ATSF's passes, supposedly named after a passenger train with A1A units had stalled there. Could this incident have occurred on the same trip where the DL-109's literally melted some traction motors?

Hell, yes.  But, as it turns out, no.  It was PAs, and they did start the train. 

It does have to be said in GE's defense that the 50/51 motors didn't actually melt, just the solder used to increase conductivity in some areas like commutator segment and brush lead connection.  Aside from the increased possibility of ground faults, I suspect some of the problems involved the molten solder compromising the insulating varnish on some of the windings.  I'm reasonably sure that the resulting shorts would cause prompt (and persistent!) problems...

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Posted by wjstix on Friday, February 1, 2019 1:41 PM

Flintlock76

I read somewhere that the ATSF preferred the F units for passenger work because of the four wheel trucks.  With the weight of the locomotive concentrated on four wheel and not six wheel trucks the F units were more sure-footed on all those hills the ATSF had to climb.  

 

 
The problem the Santa Fe (and Great Northern, maybe others) found was that E units with their A-1-A trucks were superb at running 100 MPH on flatland tracks, but tended to burn out traction motors when trying to climb mountains. With one-third of the engine's weight being supported on the unpowered idler trucks, the traction motors had to do more work. F-units, with all axles powered, worked a lot better on grades (as did GPs and SDs).
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Posted by oltmannd on Sunday, February 3, 2019 11:11 AM

Both the B "Blomberg" truck under the F units and the A-1-A truck under the E units are "swing hanger" trucks.  The A-1-A is also equalized where the B is not.

I would expect an E unit to ride better at speed due to its longer length, but probably not a huge difference.  On welded rail, the F unit would likely have stability issues at high speed.  It became standard practice for EMD higher speed 4 axles to have yaw dampers because of their relatively short length.

-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/

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Posted by zardoz on Tuesday, February 5, 2019 12:31 PM

oltmannd
I would expect an E unit to ride better at speed due to its longer length, but probably not a huge difference.

Actually, at least on jointed rail, the ride difference was huge. On welded rail the difference was not nearly as significant, but there was still a difference.

The F's trucks would beat the rail from side-to-side, as well as readily transmit the joint impacts. The E's ride was vastly superior, similar to the difference between a GP9 and an SD9; there was a reason the SD9's were refered to as "Cadillacs".

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Posted by M636C on Tuesday, February 5, 2019 10:44 PM

Are you SURE that you're not channelling those late Australian locomotives (we've just succeeded in preserving one example; look up 'The Last Streamliner' on GoFundMe) that essentially used an FP45-style 'cowl' carbody with a bulldog EMD nose?

To recall Mark Twain's famous statement, "the reports of my death were greatly exaggerated", around half of the AT26Cs are still in service with Genessee and Wyoming Australia. It was Aurizon that sold off their share, which contained the last unit built new with the EMD nose. But CLP10 ex CL17 has indeed been saved and has finally moved to a site where it can be restored.

While they look like cowl units, they are structually just stretched F units with very early HTC trucks. The angled roof was simply to allow the radiator and dynamic brake installation like that of an SDP40F. This carbody structure was required to keep the weight down to 126 long tons, giving a 21 ton axleload.

The C636 truck was described as a "high speed" truck in early Alco publicity, and compared to the trimount it certainly was better at speed.

Somehow, this design appears to have found its way to India, possibly through Licences for construction of Alco locomotives, and has appeared on some straight electric passenger locomotives in India as have some EMD Flexicoils, possibly removed from the GT16C units (sort of export SD24s) that have presumably been withdrawn by now.

So the C636 trucks have found their way into high speed passenger service, just not in the USA....

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Posted by Miningman on Tuesday, February 5, 2019 10:59 PM

Wow.. who knew? More to your Forum name than meets the eye. 

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Posted by M636C on Wednesday, February 6, 2019 4:37 AM

Miningman

Wow.. who knew? More to your Forum name than meets the eye. 

 
"M636C" was a description for a group of M636 units built in Australia, Mount Newman 5469 to 5495 which had Alco "Hi Ad" trucks instead of the standard MLW Dofasco design. The code was the converse of "C630M" applied to Montreal built C630s fitted with MLW Dofasco trucks.
 
Mt Newman preferred the Alco truck which rode very well on their all welded track. They only purchased locomotives with the MLW Dofasco truck after the builder refused to supply any more Hi Ads.
 
I spent some time leaning out of the cab of a trailing M636C watching the movement of the flexicoils on the sharper curves (the site of the recent runaway) but I never got the chance to measure the performance with transducers as I did with most types of ore car trucks.
 
Peter
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Posted by M636C on Thursday, February 7, 2019 6:54 PM

I thought I should add details of the Indian locomotives that used US Truck designs.

The locomotives are AC 25kV with DC traction motors.

They were developed from the WAM4 which used Alco Trimount trucks.

The WAP1 appeared in 1979 using EMD GLC trucks, an export version of the domestic Flexicoil. These have an asymmetric wheelbase and are rougher riding at speed than the more symmetric domestic Flexicoil, but would be a big improvement over a Trimount.

The GLC Flexicoils didn't give complete satisfaction and the Alco Hi Ad was tried, described as the "Flexicoil type II". these units were classed  WAP1 FMII but were later called WAP3. Only around 60 of these two classes were built.

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Posted by MR CARL R BYRON on Tuesday, February 12, 2019 12:32 PM

Debate remains if "FT" stood for Freight--Twenty seven hundred HP {total for cab-booster set] or simply "FreighT".

 

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Posted by MR CARL R BYRON on Tuesday, February 12, 2019 12:37 PM

"Alco Curve" was  where Santa Fe's first set of PA's died and had to start up with test train strung out behind it. ATSF 51ABA did start it with some of the highest TF an A1A A1A locomotive ever produced. See  entire story in Vernon Smith's My Life with Locomotives. Smith was on the test train in Oct, 1946.

 

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Posted by SSW9389 on Tuesday, February 12, 2019 4:05 PM

F stands for Fourteen, FT stands for Fourteen Twin and FS means Fourteen Single. 

From Wally Abbey: http://utahrails.net/loconotes/emc-ft.php 

Ed in Kentucky

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Posted by Overmod on Tuesday, February 12, 2019 5:06 PM

MR CARL R BYRON
ATSF 51ABA did start it with some of the highest TF an A1A A1A locomotive ever produced.

Small nit-pick:  That's ATSF 51LAB.  (In the days when a 'locomotive' was a semi-fixed consist of units, assigned a particular road number, the Santa Fe used "L" to designate the lead A-unit, then for still more fun designated the B-unit "A" and the trailing A-unit "B".)

Yes, no few of the F-unit consists were LABC, with C being the other A unit.  Ready for the Excedrin yet?

This numbering scheme led to some fun, if I recall correctly, when some of these engines were being traded in at EMD.  There was an extra credit (for speed recorder equipment) on the cab A units ... some of which had Bs in their numbers, so EMD accountants took them to be boosters.  ATSF complained they were being shorted on their trade-in allowance, and it took some time to track down the problem...

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Posted by M636C on Tuesday, February 12, 2019 7:32 PM

SSW9389

F stands for Fourteen, FT stands for Fourteen Twin and FS means Fourteen Single. 

From Wally Abbey: http://utahrails.net/loconotes/emc-ft.php 

Ed in Kentucky

 

I'm a strong supporter of this view...

Why would one of many EMC pre war descriptions NOT be based on the horsepower when all the others were? (well nearly all...)

But why was there a new designation? The freight units could have continued the "T" series started by the Rock Island passenger units ("TA"). Certainly the designation "E" was kept when the 567 arrived and the power went up to 2000.

It may have been the "two section" aspect that stopped the FTs from becoming T-1s or T-2s....

But apart from having a steam generator, the TA wasn't very different from a 201A engined "F unit".

Peter

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Posted by CSSHEGEWISCH on Wednesday, February 13, 2019 6:56 AM

The "T" in Rock Island's TA's stood for Twelve Hundred HP.  They were built with V-16 201A engines, almost a predecessor for the FT.

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Posted by rcdrye on Wednesday, February 13, 2019 7:37 AM

Southern Pacific used E-Units on the Sunset, Golden State and Coast routes - but required helpers for E-Unit consists on Cuesta Grade above San Luis Obispo.  SP did run E-Units in the Sierras (UP joint City of SF, with helpers) and made at least one trip with the Shasta Daylight with new E9s.  Pretty soon all of the heavy-grade trains were handled by FP7s and PAs, including the San Joaquin Valley trains. SP bought 10 SDP45 units without cowls in 1967 which allowed retirement of the remaining PAs.  The last E-Unit was retired in 1970.  E-Units returned to the Sunset under Amtrak, but the SPD45s stayed on the other SP-run trains until the SDP40Fs arrived.

AT&SF's GE passenger engines were disliked by crews.  The U28CGs (non-cowl) were assigned to the Texas Chief initially.  The U30CGs (cowl) were disliked even more for some reason. Initially assigned to the Grand Canyon and the Tulsan, a derailment at Chillicothe IL in 1969 led to their (and the U28CGs) removal from passenger service (where they were replaced by F7s).  They ended up in the freight pool, mostly as trailing units.  They were traded in as soon as their equipment trusts expired.

Amtrak trains running on the Santa Fe did not experience the same derailment issues with SDP40Fs that Amtrak trains running on the SP did.  While a lot of attention was paid to the units' hollow-bolster trucks (also used on Conrail SD40-2s) the real problem was more likely the above-frame water tanks for the boilers, which did not have any baffles.  A good slosh in a half-full tank made less than perfect track even worse.

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Posted by timz on Wednesday, February 13, 2019 12:57 PM

rcdrye
E-Units returned to the Sunset under Amtrak, but the SPD45s stayed on the other SP-run trains until the SDP40Fs arrived.

SDP45s pulled Amtrak between LA and Portland -- never on the Overland Route. That was Fs in 1971-72, then Es and Fs in summer 1973.

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Posted by rcdrye on Thursday, February 14, 2019 7:14 AM

timz
SDP45s pulled Amtrak between LA and Portland -- never on the Overland Route. That was Fs in 1971-72, then Es and Fs in summer 1973.

SDP45's worked the overland route for SP prior to Amtrak, often with an SDP45/F7B on the City.  After Amtrak day the FP7s returned until the UP Es started to run through.  Amtrak leased eight of the SDP45s (3201-3204, 3206-3209) until the SDP40Fs started arriving in 1973 or 1974  Typically two sets worked the "short train" that ran daily from Oakland to LA, the other sets worked the tri-weekly "long train" to Seattle, sometimes working through, often replaced by ex-BN F7s at Portland.  ex-SP FP7s were among the last F-Units in Amtrak service (not counting FL9s).

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Posted by Overmod on Thursday, February 14, 2019 7:50 PM

rcdrye
timz

SDP45's worked the overland route for SP prior to Amtrak, often with an SDP45/F7B on the City.

Does this need to be settled with photographic proof?

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Posted by M636C on Friday, February 15, 2019 1:34 AM

Overmod

 

rcdrye
timz

SDP45's worked the overland route for SP prior to Amtrak, often with an SDP45/F7B on the City.

 

Does this need to be settled with photographic proof?

 

"Our GM Scrapbook" (Kalmbach) page 115.

SDP45 3207 on "City of San Francisco" at Elko Nevada (no clue as to date or train direction, probably pre-Amtrak)

Peter

 

 

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