• New ES44C4 (A1A-A1A) Locomotive

  • Discussion of General Electric locomotive technology. Current official information can be found here: www.getransportation.com.
Discussion of General Electric locomotive technology. Current official information can be found here: www.getransportation.com.

Moderators: MEC407, AMTK84

  by Jay Potter
I have no insight into what assignments these units will receive on BNSF. However, as I indicated in my 1-27 posting, a design concept behind these units is that a four-motor AC-traction unit can be a viable alternative to a six-motor DC-traction unit.

My frame of reference for locomotive-testing scenarios is the program that GE and CSXT conducted in an effort to maximize the tractive effort of six-motor 4400-hp AC-traction units; and I believe that the aspect of that program that's most relevant to the current GE and BNSF program is its duration. The time period between GE's construction of the first prototype test unit and CSXT's decision to increase the tonnage ratings of the production units was five years and nine months. And an additional two years elaped between then and when the modifications were applied to preexisting standard units. During this time, unit performance in a variety of operating environments was monitored, units were modified, additional monitoring was done, and so forth.

My point is that I don't believe that anyone will know exactly how the BNSF units will perform until they are placed in service. I'm sure that GE has performance expectations based on certain weight distributions and speeds. However based on the prior CSXT testing program, it would greatly surprise me if the BNSF units were placed into service and shortly thereafter the two-unpowered-axles concept was declared either a success or a failure. My expectation is that there will be a lengthy period of time during which the units are modified in a variety of ways and that these modifications will result in significant performance changes.
  by kf7strng
Ge is testing one of these units, temporarily numbered "6600" on the Buffalo And Pittsburgh Railroad, a short line RR in Pennsylvania. I am going to try to catch a peek at it on friday, If i see it I'll try to get pictures. It's supposed to have GE demo units 6000, and 6002, as well as the observation car in the consist also.
  by GEVO
#6601 was out on the Erie test track yesterday. Video here.

If you watch the high quality version, you can clearly see this one also has the new right side nose door.
It will have to work in all types of service to be viable or it will be converted back to C-C. The acid test will be heavy haul (IE Grain, coal).
  by Allen Hazen
I am worried about the quality of railroad management if DASH9DAD is right in saying thye new four-motor locomotive "will have to work in all types of service," including heavy haul. Certainly in the past railroads have often ended up assigning locomotives designed for one type of service to others (passenger power on freights, for example), but I would hope that this could be avoided. BNSF has on the order of 7,000 locomotives. The idea of a central power-assignment office (that works out-- one would hope a BIT in advance-- which locomotives go where) dates back to the 1950s. Management has computer power far in advance of what was available even a few years ago, and -- many new locomotives being equipped with satellite radio for this and other purposes -- can monitor the exact location and status of individual locomotives.

I would suggest that BNSF ought to (i) figure out how many of its locomotives are required for high-speed intermodal (ii) plan its locomotive purchases with an ultimate goal of have somewhat LESS than that many high-power four-motor units (so: assume that a certain minority of the units pulling intermodal trains on any given day will be six-motor units that could have been doing something else) and (iii) tell the staff of the power assignment office that they lose their Christmas bonuses if a 6600 is seen on a coal train.

Railroads, because of the necessarily dispersed nature of their operations and employee locations, have always been hard to manage, but if the Air Force can keep track of which of its bombers have nukes on board, BNSF ought to be able to keep track of which of its trains get high-speed locomotives... though, given last year's red faces at the Air Force, maybe that isn't the best analogy to cite! :-)
  by Jtgshu
As a purely nostalgic note - one has to wonder if this loco is successful (I can't see why it wouldn't be) could it mean it might be the beginning of the end for some of the rare birds that BNSF has in its 4 axle fleet - namely the GP30s and GP35s (well GP28Ms or whatever they are classified as now)??????
  by FCP503
Well in Santa fe terms almost every single diesel locomotive was purchased for high priority freight usage. (exclusive of passenger units) You name it, Funits, Geeps of all shapes and sizes, SD's of every description.

Anybody remember GP50's GP60's GP60M's? Dash 8 40B's, Dash 8 40BW's even six axle Dash 8 and 9? It is fair to say that ALL of them were purchased for high speed intermodal usage.

Where are a lot of those four axle units units today? In local service taking the place of a GP7, GP9, or CF7 that was retired years back? (that displaced a steamer, or an FT most likely)

Where are the six axle units? Doing jack of all trade work? Yes, of course they are.

Traditionally the units that were unique were the units assigned for slow speed service. Back the day that might have been a U23C, or an SD39. Today that is the large fleet of AC units in coal service. What happended to the SD40-2's and SD60's that were displaced out of coal service? Jack of all trade work? Of course!

I still think that the "building block" philosophy that was popular when the SD40-2's were new was a very down to earth real world understanding of how locomotivesare utilized. Not just when they are the newest and bestest thing on rails, but over their entire lifespans.

I guess I have seen people attempt to invent the wheel enough times to be very dubious that THIS time it will be so much better.
  by tomjohn
If I am not mistaken didn't most all railway manufacturers flirt with this very same "the A1A" idea between the 1930's to about the late 1960's ?

  by Allen Hazen
Well, several builders built A1A-A1A units in the 1930s and later, but whether it was "the same" idea depends on how finely you discriminate ideas!
In the interests of adhesion, you want as much of the total weight to be on the driving axles as possible. A1A trucks are used when, for some reason or other, the weight of the machinery needed for the power you want exceeds what is permissible on the number of powered axles you will have. Possible reasons include:

(1) Really klunky primitive diesel engines. One of Baldwin's first experimental diesels, in the 1920s, I think was an A1A-A1A for this reason. General Electric catalogued (but didn't sell or build) an A1A-A1A passenger boxcab powered by the larger (800hp) version of the Ingersoll-Rand diesel engine of the 1920s.

(2) Passenger power with "first generation" technology. EMD's first 1800 hp passenger locomotives (power derived from two 12 cylinder 201A engines) was a B-B boxcab, but they quickly moved to the A1A-A1A E-unit configuration. (There's a superb series of articles on E-unit evolution by Preston Cook in the October/November/December 2008 issues of "Railroad and Railfan." ... In this case the move to A1A trucks was partly motivated by the better tracking qualities of the longer wheelbase truck, but the weight of two engines plus steam generator plus water tanks.... was a major consideration.) Alco (with the Dl-109) and Baldwin, both having heavier prime movers than EMD, had to imitate this configuration for their competitive passengerr units. Even single-engined passenger designs in the late 1940s (Alco PA, Fairbanks-Morse "Erie-Built") were heavy enough (by the time the steam heating equipment and tankage was incorporated) to require idler axles. (Though (a) F-M was able to get it down to one idler axle with their B-A1A passenger C-Liners and (b) permissible axle-loading for first generation passenger power was a good deal less than seems to be tolerated in contemporary passenger B-B units.)

(3) Power of a standard freight or roadswitcher unit in a light axleweight unit for use on lines with light rails. Alco RSC-2 and RSC-3 (basically RS-2 and RS-3 with A1A trucks) and Baldwin equivalents; also the four odd units MLW built for use on CN's Prince Edward Island lines. No market for units like this in North America since about 1960: the lines they were for have either been upgraded or abandoned.

The new ES44C4 doesn't quite match any of these profiles. Maybe -- if future locomotive technology uses a prime mover with far better power/weight ratio than current ones -- they will come to be thought of as analogues of (1). Since they are freight units for use on main lines, they aren't analogues of (2) or (3).

So: is this the SAME idea as earlier A1A-A1A diesels or not? Depends on what you mean by "same idea"!

(Reading this over, I realize that it might sound as if I am being dismissive: this is not intended! I think you raise an interesting issue-- how does the thinking behind these units compare with earlier analogous-seeming developments-- and I hope I've contributed to its discussion! Thanks for bringing it up.)
  by FCP503
I think your reason (1) is probably closest to the mark.

Outside of the two AC passenger units EMD made (and received no orders for) have any other B-B AC drive diesels been made in North America?

Citing the Alco PA series may be a very close analogy. What beside the addition of steam heat and consumables (fuel and water) pushes the weight so high as to require an A1A truck on the PA? (the additional AC equipment would be analagous here)

Also consider that A1A trucks do ride much better!!! (another reason???)

That being said one can deduce one of two reasons: One, the equipment is too heavy to construct an AC drive B-B diesel (at least for GE) or two, GE and BNSF feel building a proper 4 axle unit is just too expensive.

Another thought occurred relates to weight tranfer. Allen has been discussing the design reasoning behind GE's "HiAd" or "roller blade" truck in another thread. Having all the motors on each truck facing the same direction would apply equally wether a truck has two motors or four. I think that a B-B truck with both motors inline AND performed well would be a design challenge.

I remain sceptical of the "cost savings" notion that has been presented. I also find it hard to believe that 8 paws on the rails will ever be as good as 12. One can place all the worlds technology on board, but the steel wheel on steel rail hasn't changed.
  by MEC407
FCP503 wrote:Outside of the two AC passenger units EMD made (and received no orders for) have any other B-B AC drive diesels been made in North America?

  by MEC407
GEVO wrote:#6601 was out on the Erie test track yesterday. Video here.

If you watch the high quality version, you can clearly see this one also has the new right side nose door.
Also of note is that the ES44C4 has brake cylinders for all wheels, whereas the trailing ES44AC units have the more common arrangement of a brake cylinder for all except the center wheels.
  by Jtgshu
MEC407 wrote:
FCP503 wrote:Outside of the two AC passenger units EMD made (and received no orders for) have any other B-B AC drive diesels been made in North America?

While not directly made by EMD, Alstom built the PL42AC for NJ Transit. Its a B-B passenger engine, with 4200 HP from an EMD 710, and AC powered.

I wonder if the 4 powered axle ES44 is going to have a similar problem like the PL42 in that at times, there can be pretty bad wheelslip. Maybe its the pax gearing (its okay for 103mph) but especially in not so great rail conditions, the loco is very light on its feet and gets very slippery. On dry rail its fine, but as soon as the railhead is slightly contaminated, it becomes an adventure.

Now, with the A-1-A trucks, the loco can be much heavier, which would help tremendously with adhesion, something that the B-B PL42 can't be. (heavier that is) to keep the axle loads reasonable.
  by MEC407
Thanks Jtgshu; somehow I totally forgot about the PL42AC.
  by Jtgshu
MEC407 wrote:Thanks Jtgshu; somehow I totally forgot about the PL42AC.
hahhaha I wish I could forget about it - but at least it looks like there are only gonna be 30 of the damn things ever built! :)

and thats a good thing :)
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