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F unit question

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F unit question
Posted by ndbprr on Thursday, June 30, 2022 2:47 PM

I just watched a you tube video that claimed the F in F3,etc. really stands for 1400 hp.  I have never heard that before.  Can anyone confirm that or was the announcer speculating?

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Posted by wrench567 on Thursday, June 30, 2022 4:22 PM

 From what I understand. The F3 stood for Freight locomotive 3rd model. The F7 would be freight locomotive 7th model in the series. Why EMD put E in the front of their passenger locomotives is beyond me? Just like Caterpillar calling their first commercial tracked tractor a D2. Some people think it's because of the diesel engine. According to the official Caterpillar statement. It sounds good. That's why. The original D2 was designed to run on kerosene. Diesel fuel was not found everywhere but kerosene could be bought anywhere, even drug stores.

      Pete.

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Posted by SeeYou190 on Thursday, June 30, 2022 5:10 PM

Yes, on the ORIGINAL FT locomotive, the F stood for 1,400 horsepower. I believe a cab unit with one booster actually was rated at 1,350 horsepower.

With the ORIGINAL EA passenger service diesel, the E stood for 800 horsepower.

Interestingly, the original switchers were the SC-1, SW-1, and NW-2. The "S" stood for 600 horsepower, and the "N" for 900 horsepower. The "C" and "W" stood for cast and welded respectively for the type of frame fabrication. I do not know if there was ever a model NC-2.

Later... as rational thinking took over... "F" became synonymous with freight cab units, "SW" became used for all switchers, and for some reason passenger locomotives continued to be "E" units.

The locomotive model letters ceased to have anything to do with horsepower by the time F-3s, BL-2s, GP-7s, SW-1200s, and E-3s showed up. I do not think "GP" or "BL" ever had anything to do with horsepower.

Wow, look at that, I answered a question in the Prototype forum... I hope I was accurate.

-Kevin

Living the dream and happily modeling my STRATTON AND GILLETTE Railroad in HO scale. The SGRR is a freelanced Class A railroad as it would have appeared on Tuesday, August 3rd, 1954, in my personal fantasy world of plausible nonsense.

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Posted by CGW103 on Thursday, June 30, 2022 5:41 PM

The BL stood for Branch Line. GP stood for general purpose. And SD stood for Special Duty.

Mike

 

 

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Posted by MidlandMike on Thursday, June 30, 2022 9:19 PM

SeeYou190
With the ORIGINAL EA passenger service diesel, the E stood for 800 horsepower.

I think you might have meant 1800 hp (two 900 hp engines)

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Posted by SeeYou190 on Thursday, June 30, 2022 9:34 PM

MidlandMike
I think you might have meant 1800 hp (two 900 hp engines)

Yes.

I will leave the Prototype Information answers to better informers.

For what it is worth... Were there any real differences between the EAs, E1s, and E2s? I have been told they were all the same locomotive, the only difference being which railroad was the original owner.

-Kevin

Living the dream and happily modeling my STRATTON AND GILLETTE Railroad in HO scale. The SGRR is a freelanced Class A railroad as it would have appeared on Tuesday, August 3rd, 1954, in my personal fantasy world of plausible nonsense.

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Posted by NP Eddie on Thursday, June 30, 2022 10:06 PM

Kalmbach has two excellent books on E and F units, available on their websites. You are correct about the E units as some there road specific modifications, as the CBQ's stainless steel and the SAL pneumatic nose doors in order to access other units.

 

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Posted by ATLANTIC CENTRAL on Thursday, June 30, 2022 10:07 PM

SeeYou190

 

 
MidlandMike
I think you might have meant 1800 hp (two 900 hp engines)

 

Yes.

I will leave the Prototype Information answers to better informers.

For what it is worth... Were there any real differences between the EAs, E1s, and E2s? I have been told they were all the same locomotive, the only difference being which railroad was the original owner.

-Kevin

 

There were minor differences in the internals, but the big difference is that the car bodies were all different. The B&O EA and the ATSF E1 had similar car bodies, but not completely the same.

The UP E2 was unique.

Sheldon

    

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Posted by SSW9389 on Friday, July 1, 2022 4:14 AM

ATLANTIC CENTRAL

 

 
SeeYou190

 

 
MidlandMike
I think you might have meant 1800 hp (two 900 hp engines)

 

Yes.

I will leave the Prototype Information answers to better informers.

For what it is worth... Were there any real differences between the EAs, E1s, and E2s? I have been told they were all the same locomotive, the only difference being which railroad was the original owner.

-Kevin

 

 

 

There were minor differences in the internals, but the big difference is that the car bodies were all different. The B&O EA and the ATSF E1 had similar car bodies, but not completely the same.

The UP E2 was unique.

Sheldon

 

All B&O EA/EBs were built with Westinghouse electrical equipment. All Santa Fe E1A/E1Bs were built with GE electrical equipment. The Union Pacific E2s had one set built with Westinghouse equipment and the other set built with GE equipment. EMC settled the issue by creating near copies of the GE electrical equipment with the E3s. Data from EMD Product Data. 

Ed in Kentucky 

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Posted by BEAUSABRE on Friday, July 1, 2022 4:33 AM

 

SeeYou190
Yes, on the ORIGINAL FT locomotive, the F stood for 1,400 horsepower. I believe a cab unit with one booster actually was rated at 1,350 horsepower.

No, each FT unit was 1350 hp

SeeYou190
I do not know if there was ever a model NC-2.

"Two NC2 locomotives were built in July 1937 for the Missouri Pacific Railroad. They were functionally identical to the NC1; Pinkepank states EMC as recording, enigmatically, "Wiring" as the difference. They were EMC S/N 714 and 715, MP #4100 and 4101."

EMC Winton-engined switchers - Wikipedia

I have heard a story that "wiring" meant that they were MU equipped (rare on switchers in those fragrant days of FDR's Second Administration). But pictures look like this was not the case. I have also heard they were equipped experimentally with aluminum rather than copper wiring to see the difference in manufacturing cost. I can vouch for neither of these stories.

1) The NW2 had a 1000 hp Model 567 engine, replacing the 900 hp Winton Model 201 on earlier units, but retained the "N" designator

2) E unit originally stood for 1800 hp (two 900 hp 201's) and the letter was retained for the E6 (2000 hp - two 1000 hp 567's) and later passenger units. Everybody in railroading knew what E stood for, so why change?

3) FT, the short answer is "no one knows" - although F was a rounding up of 1350 hp per unit. Stories I've heard over the years

a) It stood for "1400 Twin" or "1400 Two Unit" as, orginally, the A and B units were semi-permanently coupled via a drawbar

b) The original hand written text for promotional materials read "F1" but the secretary who typed it up misread it for "FT" and that's how it was sent to the printer. When the material came back from the printer, it was too late to change it and have it reprinted, so they ran with it.

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Posted by BEAUSABRE on Friday, July 1, 2022 4:50 AM

SeeYou190
he locomotive model letters ceased to have anything to do with horsepower by the time F-3s, BL-2s, GP-7s, SW-1200s

Actually, the SW1200 was a 1200 hp unit and its little brothers, the SW900 had 900 hp and the SW600 had 600 hp. The SW1000/1001 were 1000 hp units and the SW1500 and various MP15 models were 1500 hp, as were the GP15's. EMD made a stab at it with its 1959 generation - 1800 hp GP18's and SD18's, 2000 hp GP20's and 2400 hp SD24's. EMD then abandoned that approach with the GP30 for marketing reasons - it would have been the GP23 (2250 hp) competing with the U25B (2500 hp). There was even an obscure light roadswitcher called the RS1325. Oh, yeah, the SW8 was 800 hp - but its contemporaries, the SW7 and SW9, were NOT 700 hp and 900 hp.

You want consistency from "Every Model Different"?

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Posted by SD70Dude on Friday, July 1, 2022 1:06 PM

I don't have my copy of the Classic Trains F-unit issue available at the moment, but as I recall it did explain what the letters actually meant.  And EMD also referred to some units as "FS", not "FT".  

Interesting that they didn't continue to use the model TA designation for a four axle unit with a single 16 cylinder engine.  


Rock Island Rocket circa 1937.jpg

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Posted by BEAUSABRE on Friday, July 1, 2022 1:34 PM

SD70Dude
And EMD also referred to some units as "FS", not "FT".  

I believe this stood for 3 unit consists with the FTSB (FT Short Booster) sandwiched between two FT A units. Remember, that EMD viewed themselves as selling complete locomotives, not units that could be assembled into a locomotive by the railroad. 

"The B-units of FTs ordered in semi-permanently coupled A-B sets, and those with couplers on both ends, have a large overhang on one end (the coupler-equipped end on the paired units) featured on no other EMD B-units. This is not present on the B-units in semi-permanently coupled A-B-A sets, which were called FTSB units (for Short Booster)."

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Posted by wjstix on Friday, July 1, 2022 1:47 PM

As noted, the original FT design was for two 1350 HP units connected with a drawbar, one A and one B, but treated like one locomotive - kinda like how a Mallet is just one locomotive. In the original design, there was no way to connect the A and B with a coupler, so you could only run them as A-B sets, or back to back in A-B/B-A sets. This produced either 2700 HP or 5400 HP.

Unfortunately, most railroads needed around 4000 HP for a mainline freight, so one A-B set wasn't enough and two were overkill. The FTSB allowed two A units to connect together with the FTSB in the middle, producing a 4050 HP lash-up. Some railroads after WW2 chose instead to buy F2 and/or F3 A units, and mate them to the FT A-B sets to produce 3-unit sets. (BTW unlike FT B units, the FTSB had no room for a steam generator and water for passenger service.)

One story for the FT name is it stood for FourTeen hundred.

 

Stix
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Posted by SSW9389 on Friday, July 1, 2022 2:46 PM

BEAUSABRE

 

 
SD70Dude
And EMD also referred to some units as "FS", not "FT".  

 

I believe this stood for 3 unit consists with the FTSB (FT Short Booster) sandwiched between two FT A units. Remember, that EMD viewed themselves as selling complete locomotives, not units that could be assembled into a locomotive by the railroad. 

"The B-units of FTs ordered in semi-permanently coupled A-B sets, and those with couplers on both ends, have a large overhang on one end (the coupler-equipped end on the paired units) featured on no other EMD B-units. This is not present on the B-units in semi-permanently coupled A-B-A sets, which were called FTSB units (for Short Booster)."

 

The FS designation was for a unit built with couplers instead of drawbars between the units. All Santa Fe FT units were actually FS units. Some 37% of all FTs were actually FS units. The FS type was originally owned by Santa Fe, Rio Grande, Southern, Missouri Pacific and Cotton Belt. 

Read this FT article by Wally Abbey: EMC's FT Locomotive (utahrails.net) 

Ed in Kentucky

 

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Posted by SeeYou190 on Friday, July 1, 2022 4:53 PM

SSW9389
The FS designation was for a unit built with couplers instead of drawbars between the units. All Santa Fe FT units were actually FS units.

Thanks for that information. This clears up and answers a lot of confusion I had about the FS designation.

-Kevin

Living the dream and happily modeling my STRATTON AND GILLETTE Railroad in HO scale. The SGRR is a freelanced Class A railroad as it would have appeared on Tuesday, August 3rd, 1954, in my personal fantasy world of plausible nonsense.

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Posted by Mykhalin on Friday, July 1, 2022 9:24 PM

BEAUSABRE
I believe this stood for 3 unit consists with the FTSB (FT Short Booster) sandwiched between two FT A units. Remember, that EMD viewed themselves as selling complete locomotives, not units that could be assembled into a locomotive by the railroad.

 

Part of this was on the railroad unions. With steam, each locomotive required a crew, so if you stuck four diesel locomotives on the train, they expected (demanded) four crews to be called, not one. Drawbars and cabless B-units were initial solutions to a problem that had to be ironed out. And "ironed" because some locomotives lacked MU connections, some locomotives - usually from different manufacturers - couldn't MU with each other, and because the diesel came at a time when traffic was ramping down post-WWII just as employees were returning from military service, unions were willing to fight hard to get compensation as the writing was on the wall for fewer needed employees in the diesel era.

The air brake had reduced the numbers of brakemen needed. The doodlebug the size of passenger train crews. The diesel the number of crews in general. State and federal laws reduced the size of a "full crew" from 5 or 6 down to 3, and eventually two or even one in the post-caboose era. And nowadays (in the computer era) there are automated trains without any crew at all. Progress! .......... NOT!

 

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Posted by Enzoamps on Saturday, July 2, 2022 3:28 PM

I have a stack of Classic Trains in the ...reading...room.  One is the E-units issue, I have read it many many times.  Explains all the E-units.

https://railroadtreasures.com/products/classic-trains-2012-summer-e-unit-ea-to-e9-model-by-model-super-chief

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Posted by John-NYBW on Saturday, July 2, 2022 8:36 PM

SeeYou190

Yes, on the ORIGINAL FT locomotive, the F stood for 1,400 horsepower. I believe a cab unit with one booster actually was rated at 1,350 horsepower.

Seems like an odd way to designate horsepower especially given it could just as easily stand for 1500. On the other hand, it's no more strange than the UP designating their Northerns as FEF which stood for Four-Eight-Four. I brought this up about ten years ago and we had a lot of fun comming up with acronyms for other wheel arrangements such as the 2-8-8-2.

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Posted by wjstix on Tuesday, July 5, 2022 1:11 PM

It's interesting (to me anyway) that for the first 20 years or so of diesels, horsepower seemed to be a key identifier. Trains magazine in the 1950s might label a picture of a train pulled by 3 GP-7s as having "three 1500 HP GM diesels".

Stix
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Posted by BEAUSABRE on Tuesday, July 5, 2022 7:47 PM

wjstix
It's interesting (to me anyway) that for the first 20 years or so of diesels, horsepower seemed to be a key identifier. Trains magazine in the 1950s might label a picture of a train pulled by 3 GP-7s as having "three 1500 HP GM diesels".

That's because some manufacturers didn't use model numbers (many Alco first generation model numbers were retroactively applied, Lima "model numbers" were invented by fans), railfans had started out with steam and steam locos didn't have model numbers, so why should there be ones for diesels (note that EMD, the subsidiary of a car maker (cars did have models thanks to Mr Ford), invented locomotive model numbers) so either weren't aware they existed or interested in them and railfans were not conversant with what the models were for the manufacturers that did use model numbers. For example, many fans thought the difference between a GP7 and a GP9 was that GP9's had dynamic brakes and GP7's didn't. It wasn't until the rise of a group of young diesel fans (disdained by the older steam crowd) around Cincinnatti that coalesced to publish Extra 2000 South and David P Morgan's then controversial decision to publish the Diesel Spotters Guide in 1967 that information about the various diesels became widely available. And yes, I still have my copy, yellowed and dog eared, of the DSG. I DEVOURED it when it arrived from Kalmbach and couldn't put it down, I was amazed at what I was learning on each new page!

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Posted by wjstix on Wednesday, July 6, 2022 9:18 AM

BEAUSABRE
For example, many fans thought the difference between a GP7 and a GP9 was that GP9's had dynamic brakes and GP7's didn't.

Funny, I was just watching a video of someone touring a railroad museum last night and they said that very thing. Of course, it comes from Lionel. (This guy was a 3-rail operator / collector.) Lionel's "GP7" and "GP9" used identical bodies, except the "GP9" had a dynamic brake 'blister' and the "GP7" didn't.

IIRC Alco used "DL" ("Diesel Locomotive" I presume) for their locos in the early years. Soo Lines two RS-27s (415-416) were nicknamed "the Dolly sisters" based on Alco's DL-640 designation.

Stix

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