Trains.com

Why were E units not suitable for freight?

4585 views
65 replies
1 rating 2 rating 3 rating 4 rating 5 rating
  • Member since
    January 2009
  • From: Maryland
  • 11,782 posts
Posted by ATLANTIC CENTRAL on Sunday, June 26, 2022 3:00 PM

BaltACD

 

 
ATLANTIC CENTRAL
 
SD70Dude

What was the highest speed gearing anyone ordered F's with?  I know some E's had a maximum speed in the 115-120 mph range, and perhaps ran somewhat faster if the overspeed was disabled (not that crews would ever monkey with something like that).  

VIA and Amtrak both have pretty long track records running Blomberg B's in the 90-110 mph range under F40's and F59's, though from watching VIA's units bounce over switches at 70-80 mph I'm not sure how smoothly they ride. 

The fastest gearing on F2's, F3's, F7's, FP7's and F9's was 56/21 for a top speed between 102 and 105 mph. The next gear ratio down was 57/20 rated for 95 mph.

The fastest E unit gearing was 52/25 for a rated speed of 117 mph. It is my understanding that many/most E units were geared 55/22 for max speed of 98 mph.

Sheldon

 

Still recall the cab ride I got on B&O #9 from Garrett to Chicago in 1959 or 1960 - Train left Garrett about 1 hour late - the headlight of #5 The Capitol Limited was seen coming in behind #9 running On Time as we departed.  Leaving Garrett, the engineer opened up the two E units on #9 and away we went across the flat lands of Northern Indiana - at several points in time I would stand behind the engineer and observe the speed recorder registering between 115 & 119 MPH.  #9 passed Pine Jct about 2 minutes ahead of schedule.  B&O had the high speed gearing on their E's, at least in that period of time.

 

Yes, I believe they all had the high speed gearing on the B&O, and that is why trains crossing the mountains on the old mainline often had 3 or 4 E units, geared for speed, not for power, on a railroad were most passenger equipment was rebuit heavyweights.

Sheldon

    

  • Member since
    May 2003
  • From: US
  • 22,757 posts
Posted by BaltACD on Sunday, June 26, 2022 2:40 PM

ATLANTIC CENTRAL
 
SD70Dude

What was the highest speed gearing anyone ordered F's with?  I know some E's had a maximum speed in the 115-120 mph range, and perhaps ran somewhat faster if the overspeed was disabled (not that crews would ever monkey with something like that).  

VIA and Amtrak both have pretty long track records running Blomberg B's in the 90-110 mph range under F40's and F59's, though from watching VIA's units bounce over switches at 70-80 mph I'm not sure how smoothly they ride. 

The fastest gearing on F2's, F3's, F7's, FP7's and F9's was 56/21 for a top speed between 102 and 105 mph. The next gear ratio down was 57/20 rated for 95 mph.

The fastest E unit gearing was 52/25 for a rated speed of 117 mph. It is my understanding that many/most E units were geared 55/22 for max speed of 98 mph.

Sheldon

Still recall the cab ride I got on B&O #9 from Garrett to Chicago in 1959 or 1960 - Train left Garrett about 1 hour late - the headlight of #5 The Capitol Limited was seen coming in behind #9 running On Time as we departed.  Leaving Garrett, the engineer opened up the two E units on #9 and away we went across the flat lands of Northern Indiana - at several points in time I would stand behind the engineer and observe the speed recorder registering between 115 & 119 MPH.  #9 passed Pine Jct about 2 minutes ahead of schedule.  B&O had the high speed gearing on their E's, at least in that period of time.

Never too old to have a happy childhood!

              

  • Member since
    April 2007
  • From: Bridgman, MI
  • 203 posts
Posted by bogie_engineer on Sunday, June 26, 2022 11:02 AM

ATLANTIC CENTRAL

 

SD70Dude

What was the highest speed gearing anyone ordered F's with?  I know some E's had a maximum speed in the 115-120 mph range, and perhaps ran somewhat faster if the overspeed was disabled (not that crews would ever monkey with something like that).  

VIA and Amtrak both have pretty long track records running Blomberg B's in the 90-110 mph range under F40's and F59's, though from watching VIA's units bounce over switches at 70-80 mph I'm not sure how smoothly they ride.

 

 

 

The fastest gearing on F2's, F3's, F7's, FP7's and F9's was 56/21 for a top speed between 102 and 105 mph. The next gear ratio down was 57/20 rated for 95 mph.

The fastest E unit gearing was 52/25 for a rated speed of 117 mph. It is my understanding that many/most E units were geared 55/22 for max speed of 98 mph.

Sheldon

 

These speeds for the F and E units are confirmed by Blomberg in a textbook on diesel locomotive trucks he co-authored in 1945 stating 95 and 117 mph for those trucks, respectively, of which I have a copy.

EMD's recent use of the B1 arrangement on the GT46PAC for India was driven by the need to save weight to meet the axle load requirement. Starting with the HTSC export frame developed for the GT46MAC, the truck engineer for that project was planning to use an A-1-A motor arrangement when I suggested a B1 arrangement should be considered, especially since it offered the possibility of elimination of the end transom to save additional weight. When studied for weight shift, it proved to be the best option for that given the traction motor orientation so that was path chosen. However, the truck engineer was afraid to remove the end transom for structural reasons (I would have done it if given the choice).

A few years later, the 4 motor arrangement for an SD70ACe-P4 was requested by sales to compete with the GE C4 and again, the B1 was considered the best performer.

However, none of us involved with these recent models were influenced or even knew of the 1B arrangement on the Santa Fe units. The GA12 was well known; EMD still has a flat car with loading grids on it that is equipped with the prototype for that truck. We didn't think of that as a 1B truck, rather just a "pony truck", as it was known, added on since it doesn't share a frame with the driven truck.

So thanks SD60MAC9500 for that historical information.

Dave

 

  • Member since
    January 2009
  • From: Maryland
  • 11,782 posts
Posted by ATLANTIC CENTRAL on Saturday, June 25, 2022 10:35 PM

SD70Dude

What was the highest speed gearing anyone ordered F's with?  I know some E's had a maximum speed in the 115-120 mph range, and perhaps ran somewhat faster if the overspeed was disabled (not that crews would ever monkey with something like that).  

VIA and Amtrak both have pretty long track records running Blomberg B's in the 90-110 mph range under F40's and F59's, though from watching VIA's units bounce over switches at 70-80 mph I'm not sure how smoothly they ride.

 

The fastest gearing on F2's, F3's, F7's, FP7's and F9's was 56/21 for a top speed between 102 and 105 mph. The next gear ratio down was 57/20 rated for 95 mph.

The fastest E unit gearing was 52/25 for a rated speed of 117 mph. It is my understanding that many/most E units were geared 55/22 for max speed of 98 mph.

Sheldon

    

  • Member since
    December 2017
  • From: I've been everywhere, man
  • 4,031 posts
Posted by SD70Dude on Saturday, June 25, 2022 10:14 PM

What was the highest speed gearing anyone ordered F's with?  I know some E's had a maximum speed in the 115-120 mph range, and perhaps ran somewhat faster if the overspeed was disabled (not that crews would ever monkey with something like that).  

VIA and Amtrak both have pretty long track records running Blomberg B's in the 90-110 mph range under F40's and F59's, though from watching VIA's units bounce over switches at 70-80 mph I'm not sure how smoothly they ride.

Greetings from Alberta

-an Articulate Malcontent

  • Member since
    January 2019
  • 1,226 posts
Posted by Erik_Mag on Saturday, June 25, 2022 9:38 PM

Overmod

But (as I recall) the ATSF 1-Bs were done for improved guiding stability and lower oscillation at high speed

That's presumably related to why EMD continued to sell E's long after they started selling passenger F's - the A1A was probably better at high speed than the Blomberg two axle trucks.

  • Member since
    September 2002
  • From: Harrison Township, Michigan
  • 1,464 posts
Posted by SD60MAC9500 on Saturday, June 25, 2022 4:29 PM
 

Overmod

But (as I recall) the ATSF 1-Bs were done for improved guiding stability and lower oscillation at high speed, not weight distribution, and would have done little if anything to remediate weight-transfer starting tractive effort issues.

 

That's correct. My reply was to Balts point about EMD's history with 1B truck arrangements.

 
 
Rahhhhhhhhh!!!!
  • Member since
    September 2003
  • 19,055 posts
Posted by Overmod on Saturday, June 25, 2022 4:25 PM

But (as I recall) the ATSF 1-Bs were done for improved guiding stability and lower oscillation at high speed, not weight distribution, and would have done little if anything to remediate weight-transfer starting tractive effort issues.

  • Member since
    September 2002
  • From: Harrison Township, Michigan
  • 1,464 posts
Posted by SD60MAC9500 on Saturday, June 25, 2022 3:57 PM
 

BaltACD

 

 
SD60MAC9500
 
bogie_engineer 
BaltACD 
Ulrich
BNSF order a bunch of A-I-A Es4400CWs... likely some of those have been used on mineral trains.  

Remember on that group of engines, the '1' axle can be lifted so that the powered axles apply the full weight of the locomotive to the rail.  These units are also geared for freight service, not passenger.  On E units the non-powered axle carried its own share of weight on the rail, thus reducing the amount of weight the powered axles applied to the rail thus reducing their 'tractive effort'. 

The axle lifting device on the center axle of the GE C4 locos does not fully lift the axle off the rail - it ups the weight on the driven axles to around 79,000 lbs. each but the idler axle still carries significant weight.  

Question. Why did GE not follow EMD and go with a B1-1B axle arrangement? That produces better traction than an A1A in freight service. I've heard from a few BNSF hoggers they don't really like the A1A truck. The traction just isn't there compared to a D9 or ES44DC.

 

Primarily because GE came out with the A-1-A solution years befoe EMD came up with the 1B arrangement.

 

Actually quite the contrary.. Going back to 1938. EMC had experimented with a 1B-1B truck on a twin unit 1800HP BB owned by ATSF. EMC would go on to modify Santa Fe #1 by seperating its A, and B units. The A-unit became #1. The B-unit #10.

No. 1 was rebuilt with the 1B-1B truck concept on its lead truck first. The rear truck was swapped out for another 1B truck later. It would seem that Progress/EMD revisited this old setup and revised it. Creating the B1-1B setup on the SD70ACe-P4.

https://en.wikipedia.org/wiki/EMC_1800_hp_B-B#Santa_Fe_1

The lead truck has been swapped in this photo. http://www.rrpicturearchives.net/showPicture.aspx?id=3339884

Photo with both 1B trucks http://www.northeast.railfan.net/images/tr_sf1.jpg

I'll also add. EMD produced for Indian Railways the GA12 export unit. Which utilized a 1B-B1 setup.

https://www.flickr.com/photos/29903115@N06/49979811153

 

 
 
 
 
 
 
 
Rahhhhhhhhh!!!!
  • Member since
    November 2021
  • 116 posts
Posted by JayBee on Friday, June 24, 2022 8:44 PM

anglecock

As far as I know the E units were used by Iron Mines up in Minnisota.

 

Not true, Great Northern operated E-7s that regularly ran the "Gopher" and "Badger" between the Twin Cities and Twin Ports, but they never used their E-units on freight. C&NW and Milw Rd had passenger train usages for their later E-units.

 

 

  • Member since
    April 2007
  • From: Bridgman, MI
  • 203 posts
Posted by bogie_engineer on Thursday, June 23, 2022 6:48 PM

timz

 

 
bogie_engineer
EMD axles are biased via the primary spring arrangement to be 75Klbs on the driven axles and 60Klbs on the idlers

 

That's the normal weight distribution, before any shifting?

 

 

Yes, those are static axle loads.

  • Member since
    September 2003
  • 19,055 posts
Posted by Overmod on Thursday, June 23, 2022 11:31 AM

timz
That's the normal weight distribution, before any shifting?

That is my understanding.

Note that the weight transfer is proportional to the acceleration, and modern locomotives with the 'elephant feet' secondary springing can't cock the sideframes in the way a certer-pivoted truck would.  It may be interesting to see what happens with monster heavy consists which see heavy power changes while moving at conservative PSR road speed... but I doubt differential adhesion is as much of a concern as it was in the era of unmodulated wheelslip 'control'.

  • Member since
    February 2005
  • 2,095 posts
Posted by timz on Thursday, June 23, 2022 11:24 AM

bogie_engineer
EMD axles are biased via the primary spring arrangement to be 75Klbs on the driven axles and 60Klbs on the idlers

That's the normal weight distribution, before any shifting?

  • Member since
    April 2007
  • From: Bridgman, MI
  • 203 posts
Posted by bogie_engineer on Thursday, June 23, 2022 9:50 AM

As BaltACD said, GE came out with their A-1-A with their patented weight shift claptrap before EMD offered the B1-1B option in response. The EMD arrangement offers the best weight shift performance under traction when the motors are arranged all on the same side of the axle - A-1-A is superior if the motors are on the inboard sides of the axles, which they are not in the GE truck. The EMD axles are biased via the primary spring arrangement to be 75Klbs on the driven axles and 60Klbs on the idlers so performance between the two is about the same.

  • Member since
    May 2003
  • From: US
  • 22,757 posts
Posted by BaltACD on Wednesday, June 22, 2022 9:14 PM

SD60MAC9500
 
bogie_engineer 
BaltACD 
Ulrich
BNSF order a bunch of A-I-A Es4400CWs... likely some of those have been used on mineral trains.  

Remember on that group of engines, the '1' axle can be lifted so that the powered axles apply the full weight of the locomotive to the rail.  These units are also geared for freight service, not passenger.  On E units the non-powered axle carried its own share of weight on the rail, thus reducing the amount of weight the powered axles applied to the rail thus reducing their 'tractive effort'. 

The axle lifting device on the center axle of the GE C4 locos does not fully lift the axle off the rail - it ups the weight on the driven axles to around 79,000 lbs. each but the idler axle still carries significant weight.  

Question. Why did GE not follow EMD and go with a B1-1B axle arrangement? That produces better traction than an A1A in freight service. I've heard from a few BNSF hoggers they don't really like the A1A truck. The traction just isn't there compared to a D9 or ES44DC.

Primarily because GE came out with the A-1-A solution years befoe EMD came up with the 1B arrangement.

Never too old to have a happy childhood!

              

  • Member since
    September 2002
  • From: Harrison Township, Michigan
  • 1,464 posts
Posted by SD60MAC9500 on Wednesday, June 22, 2022 8:49 PM
 

bogie_engineer

 

 
BaltACD

 

 
Ulrich
BNSF order a bunch of A-I-A Es4400CWs... likely some of those have been used on mineral trains. 

 

Remember on that group of engines, the '1' axle can be lifted so that the powered axles apply the full weight of the locomotive to the rail.  These units are also geared for freight service, not passenger.  On E units the non-powered axle carried its own share of weight on the rail, thus reducing the amount of weight the powered axles applied to the rail thus reducing their 'tractive effort'.

 

 

 

 

The axle lifting device on the center axle of the GE C4 locos does not fully lift the axle off the rail - it ups the weight on the driven axles to around 79,000 lbs. each but the idler axle still carries significant weight. 

 

Question. Why did GE not follow EMD and go with a B1-1B axle arrangement? That produces better traction than an A1A in freight service. I've heard from a few BNSF hoggers they don't really like the A1A truck. The traction just isn't there compared to a D9 or ES44DC.

 
Rahhhhhhhhh!!!!
  • Member since
    September 2002
  • From: Harrison Township, Michigan
  • 1,464 posts
Posted by SD60MAC9500 on Wednesday, June 22, 2022 8:46 PM
 

BaltACD

 

 
Ulrich
BNSF order a bunch of A-I-A Es4400CWs... likely some of those have been used on mineral trains. 

 

Remember on that group of engines, the '1' axle can be lifted so that the powered axles apply the full weight of the locomotive to the rail.  These units are also geared for freight service, not passenger.  On E units the non-powered axle carried its own share of weight on the rail, thus reducing the amount of weight the powered axles applied to the rail thus reducing their 'tractive effort'.

 

From what I understand.. This is why once F-Units became available in a pax version. Sants Fe never looked at E units for passenger service again.

The A-1-A truck made for poor traction in graded territory out West.

 
 
 
Rahhhhhhhhh!!!!
  • Member since
    April 2007
  • From: Bridgman, MI
  • 203 posts
Posted by bogie_engineer on Wednesday, June 22, 2022 8:37 PM

BaltACD

 

 
Ulrich
BNSF order a bunch of A-I-A Es4400CWs... likely some of those have been used on mineral trains. 

 

Remember on that group of engines, the '1' axle can be lifted so that the powered axles apply the full weight of the locomotive to the rail.  These units are also geared for freight service, not passenger.  On E units the non-powered axle carried its own share of weight on the rail, thus reducing the amount of weight the powered axles applied to the rail thus reducing their 'tractive effort'.

 

 

The axle lifting device on the center axle of the GE C4 locos does not fully lift the axle off the rail - it ups the weight on the driven axles to around 79,000 lbs. each but the idler axle still carries significant weight. 

  • Member since
    May 2003
  • From: US
  • 22,757 posts
Posted by BaltACD on Wednesday, June 22, 2022 6:31 PM

Ulrich
BNSF order a bunch of A-I-A Es4400CWs... likely some of those have been used on mineral trains. 

Remember on that group of engines, the '1' axle can be lifted so that the powered axles apply the full weight of the locomotive to the rail.  These units are also geared for freight service, not passenger.  On E units the non-powered axle carried its own share of weight on the rail, thus reducing the amount of weight the powered axles applied to the rail thus reducing their 'tractive effort'.

Never too old to have a happy childhood!

              

  • Member since
    September 2003
  • 19,055 posts
Posted by Overmod on Wednesday, June 22, 2022 1:22 PM

Ulrich
BNSF order a bunch of A-I-A Es4400CWs... likely some of those have been used on mineral trains.

If I remember correctly the allocation of both the A-1-A and 1-B trucked units was away from heavy mineral service... but the discussion of E units refers to passenger A-1-A trucks, optimized for high speed and low polar moment of inertia.  I think the provision of effective AC motors and power transmission without the prime mover exceeding the capability of four of them is a big part of the 'modern' approach, where you need six axles for the weight and length but only four to get higher-speed horsepower to the rail.

It might have been interesting to see use of a 'traction increasing' mmechanism for E units -- GM used a similar approach on some export units  during the production years of the modern Es.

  • Member since
    February 2003
  • From: Guelph, Ontario
  • 4,472 posts
Posted by Ulrich on Wednesday, June 22, 2022 1:04 PM

BNSF order a bunch of A-I-A Es4400CWs... likely some of those have been used on mineral trains. 

  • Member since
    September 2003
  • 19,055 posts
Posted by Overmod on Wednesday, June 22, 2022 9:04 AM

BaltACD
 

The closest I suspect you'll come to an A-1-A in mineral service would be the Baldwin passenger shark B-units, which were regularly run out of Columbus sandwiched between the likes of RF-16s. 

 

If they were ever placed in such service it would be for the purpose of burning up their traction motors from overcurrent operation for a excessive amount of time.

I think the rationale was that the units had Baldwin hexapole motors, which to my knowledge only N&W figured out how to destroy in service, and they constituted somewhat longish 2000hp four-axle boosters.  Note that PRR also experimented with reducing horsepower on BP-20 cab units to 1600, to match the RF16 rating... it was not successful enough to 'do' all the units, but the converted ones ran satisfactorily in service until their untimely end.

  • Member since
    May 2003
  • From: US
  • 22,757 posts
Posted by BaltACD on Wednesday, June 22, 2022 8:49 AM

Overmod
 
BaltACD
Have never, ever heard of E units being used in ore service by any carrier. 

The closest I suspect you'll come to an A-1-A in mineral service would be the Baldwin passenger shark B-units, which were regularly run out of Columbus sandwiched between the likes of RF-16s. 

It might be interesting to see if the Erie-builts were ever used in heavy service -- I doubt it, though.

If they were ever placed in such service it would be for the purpose of burning up their traction motors from over current operation for a excessive amount of time.

Never too old to have a happy childhood!

              

  • Member since
    September 2003
  • 19,055 posts
Posted by Overmod on Wednesday, June 22, 2022 8:29 AM

BaltACD
Have never, ever heard of E units being used in ore service by any carrier.

The closest I suspect you'll come to an A-1-A in mineral service would be the Baldwin passenger shark B-units, which were regularly run out of Columbus sandwiched between the likes of RF-16s.

It might be interesting to see if the Erie-builts were ever used in heavy service -- I doubt it, though.

  • Member since
    February 2003
  • From: Guelph, Ontario
  • 4,472 posts
Posted by Ulrich on Monday, June 20, 2022 7:26 PM

jeffhergert

 

 
BEAUSABRE

 

 
Ulrich
Not sure why CP bought only two..perhaps they were part of a larger order that was cancelled. Diddo for the only RSD17 ever built by MLW.. after testing on both CN and CP, neither road wanted more,

 

I've got a hunch you answered your own question - they were built either as demonstrators no one wanted to try or GMD persuaded CP to give them a try, CP decided not to bite, but when GMD offered them at a discount to get them off their hands, CP took them. 

 

 

 

One of the CP's GP30 is one of the switchers at a Fremont, NE elevator.  It's now blue, but you can see spots where red is showing through.

I've read the other one also still exists.

Jeff

 

Met this GP30 as well.. CP seemed to favour them for trains east of Montreal in the 70s. In the 90s they went to Vancouver Island for a few years until retirement. 

  • Member since
    February 2003
  • From: Guelph, Ontario
  • 4,472 posts
Posted by Ulrich on Monday, June 20, 2022 7:22 PM

SD70Dude

 

 
jeffhergert

One of the CP's GP30 is one of the switchers at a Fremont, NE elevator.  It's now blue, but you can see spots where red is showing through.

I've read the other one also still exists.

Jeff

 

 

It's here in Edmonton, at the Alberta Railway Museum, albeit in pretty rough shape.  It's had a tough life and passed through several owners during its post-CP existence, and we only got it to save it from the torch after the previous ownership went belly up (it's a long story).  It's not a restoration priority and the museum has been looking to deaccession it to a better home for some years now. 

https://www.railpictures.net/photo/372120/

I helped board up the smashed windows last summer. 

 

In the summer of 79 my brother and I got a cab tour of this engine in Sherbrooke, QC. We asked the engineer if we could have a look inside, and he told us jokingly that we could take the train to Megantic. Great times when kids could do that. It was one of the few times we took lots of pictures..colour slides...and I wish I could find them. 

  • Member since
    July 2016
  • 1,929 posts
Posted by Backshop on Monday, June 20, 2022 6:29 PM

None of the iron ore railroads owned E8s (GN, NP, DM&IR, SOO) and only the GN owned a few E7s. The C&NW owned some but they had better uses of them in suburban service.

  • Member since
    May 2019
  • 931 posts
Posted by BEAUSABRE on Monday, June 20, 2022 6:16 PM

Which leads to the question of what mines or railroads?

  • Member since
    May 2003
  • From: US
  • 22,757 posts
Posted by BaltACD on Monday, June 20, 2022 6:06 PM

anglecock
As far as I know the E units were used by Iron Mines up in Minnisota.

Have never, ever heard of E units being used in ore service by any carrier.  E unit tonnage ratings, in DRAG service on tonnage trains is totally anemic in comparison to F units that are geared and weighted to haul freight.  Remember, on E units the middle axle of each truck is unpowered, but still applies weight to the rail.

Never too old to have a happy childhood!

              

Join our Community!

Our community is FREE to join. To participate you must either login or register for an account.

Search the Community

Newsletter Sign-Up

By signing up you may also receive occasional reader surveys and special offers from Trains magazine.Please view our privacy policy