Assuming the six-wheel truck is properly designed, the reduced axle loading means the locomotive will be kinder to the track structure except on the very sharpest curves.
A-1-A - A-1-A or B-1- 1-B high speed freight, intermodal, passenger, lowest fraction of adhesion, and lowest starting tractive effort for given horsepower BNSF only?
B - B Passenger and high speed and branch line (short line) freight, intermodal. Amtrak and commuter authorities
C - C Normal freight, passenger in mountains (would be a good idea is the locos were not running terminal to terminal)
C - C (AC motors) heavily ballested for extra weight coal and ore, coal and ore and general freight in mountains, highest starting tractive effort and factor of adhesion for given horsepower. Tpically NS and CXS
More Coming
The TRAINS Newswire of Tuesday, January 23, 2012 indicated that 175 more ES44C4's are coming.
A pair of ES44C4 units by the "Natural Crossover" (M.P. 39.1) near Victorville, CA north of Cajon Pass.
With such an order of confidence, the model must be quite successful.
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----------------------------------------------------------------------------------------------------------------------------------- K.P.’s absolute “theorem” from early, early childhood that he has seen over and over and over again: Those that CAUSE a problem in the first place will act the most violently if questioned or exposed.
A Perfect Set of Spiffy ES44C4's in a Cool Looking Place
Part IV (of I-IV)
A Not So Perfect Consist, and Two Types of Center Axils
An eastbound train soon came along.
(In the above photo, note that the second unit is a rare for Cajon Pass BNSF EMD SD70ACe. The third unit is one of the GE ES44C4 types being spoken about in this thread.)
At Blue Cut proper, on the above train, one unit's traditional NON-ES44C4 center axil was focused upon.
In contrast, another close-up of an actual ES44C4 truck center lift-type wheel and axil.
The above photo is of the REAR truck, whereas the FRONT truck was viewed in Part I, but both are of ES44C4 trucks, though of slight differing appearance. In both front and rear views, the small area the axil can raise the wheel off the rail in is visible
Shiny, gleaming, and perfect sets of anything are rare these days. But, when such a set of ES44C4's showed up in Cajon Pass, well, that was more than K.P. had hoped for ... and now you too have gotten to see it ... and have seen the unique rise and lower center axil slotting area rather close-up. Truly, it is a unique truck design.
Part III (of I-IV)
Was It Really a Perfect Set? You Bet!
After the above, a return eastward was made ... but that came to an abrupt reversal when the tail end of the train was spotted!
Two DPU'ed ES44C4's in dynamic brake mode (leftward) brought up the tail end of the three ES44C4 headed train, so that it was chased and followed a bit.
Again, a westbound photo leftward movement: The normally dry wash Keenbrook area:
So, there we have it, a perfect group of ES44C4's, with numbers 6805, 6808, 6802 up front, and DPU's 6803 and 6804 on the rear end
Continued in Part IV
Part II (of I-IV)
The three ES44C4 units met another train railroad west of CP CAJON.
And soon thereafter went by Blue Cut.
Finally, the stunning consist headed off further west.
Continued in Part III
Part I (of I-IV)
A morning, perfect temperature Cajon Pass (CA) was visited today (Thursday, October 20, 2011), with the intent of hopefully photographing an ES44C4 and the center lift-able wheels of its trucks.
It didn't take long, and a spectacular threesome of ES44C4's came.
Its truck's center axil was focused upon.
On the far side of the trio is Main 1, the trio is on Main 2, both mains are on the 2.2% grade, with the foreground separate 3% Main 3 meeting and following the other two mains
Continued in Part II
beaulieu Look at the two air cylinders near the middle of the truck on the photo of BNSF 6691 above. Those are only found on ES44C4s. When extended they transfer weight off the middle axle onto the two end (powered) axles.
Look at the two air cylinders near the middle of the truck on the photo of BNSF 6691 above. Those are only found on ES44C4s. When extended they transfer weight off the middle axle onto the two end (powered) axles.
YoHo1975 Also note 7264 has the standard trucks so you can see the difference clearly.
Also note 7264 has the standard trucks so you can see the difference clearly.
Thanks for the information. The difference is clear when you know what to look for. Wasn't it nice of UP to couple these two together so we could see the difference?
One more dumb question though: Wouldn't it have been cheaper to build a B-B version of the ES44AC? The larger truck frame, wheel, axle, etc. have got to be a lot heavier and more expensive, not to mention more expensive to haul around. Starts to remind me of the dummy B-units that used to be common in model.
ChuckAllen, TX
Diesels have never managed to keep my attention for long so this may be a dumb question but, how do I tell the difference between an ES44C and an ES44C4 (without getting close enough to read a builder's plate if there is one)?
WITH CATS MONEY EMD WILL BE THE BEST LOCOMOTIVE. IT ALWAYS WAS AND IS THE BEST. I SHOULD KNOW BECAUSE I 'M IN THE CAB!!!
I suspect that with all the gensets, GP22s and other rebuilt four axle units that DC will stay around for a good while, maybe just not on high speed stack trains.
-Doc
The Lack of ES44C4's in Cajon Pass
Cajon Pass is kind of home turf for K.P., and he traverses it periodically, but the lack of ES44C4's in the Pass of late has been disappointing. Once in a while one shows up.
An ES44C4 glides westbound (leftward) almost into the crossovers location known as CAJON
Anybody know where they all are at?
Best,
K.P.
beaulieu (7-22):
Thanks for the clarification and technical information, beaulieu. So, I missed the 300 figure by 20. I guess that isn't too bad for a half-follower of BNSF.
So, as I understand it ...
6600-6624 (25 units in the first order)
6625-6652 (28 additional units added)
6653-6869 (the 227 units in the big order)
[6870-6889] (20 unit slots available for a possible future order)
6890-6899 (10 pre-production Tier 3 test units)
I wonder what BNSF will do when the ES44C4's reach 7200?
Take care,
Are they saving the vacant numbers for more test units?
Watch my videos on-line at https://www.youtube.com/user/AndrewNeilFalconer
K. P. Harrier Reportedly, the total BNSF ES44C4 series now runs from 6600 to 6899. That is 300 units! The numbers have grown fast!
Reportedly, the total BNSF ES44C4 series now runs from 6600 to 6899. That is 300 units!
The numbers have grown fast!
BNSF 6890 - 6899 are pre-production Tier 3 test units. BNSF's 2011 order will now consist of 6653 - 6869 and 6890 - 6899, still the same 227 units.
On Thursday, July 21, 2011, 6894 was photographed as a trailing unit at Summit in Cajon Pass, CA.
The ES44C4 is a derivation of the high-tractive-effort ES44ACs that GE has been building for CSXT. Both use the same traction-control software and have traction motors capable of producing 36,000 pounds of tractive effort per motor, adhesion permitting, compared to the 30,000-pound limit of conventional ES44AC motors. If the weight of two traction motors and two axle gears is added to the 416,000-pound nominal weight of a four-motor ES44C4, the resultant total is about 432,000 pounds, which is the nominal weight of a CSXT ES44AC.
oltmannd The max TE from a six axle DC vs four axle AC should be about a wash.
The max TE from a six axle DC vs four axle AC should be about a wash.
That is true, the absolute max should be similar. However, the 4 motor AC will be able to generate higher average TE due to its superior traction control software and frequency drive which allows all the powered axles to always rotate at the same rpm. With DC, once an axle breaks free on on a hard pull, it will try to "run away" from the others. The experience on CSX has been for a given tractive effort required , the ACs will always pull more reliably than the DCs. On a really hard pull, you will run into DC thermal limits at max tractive effort, with AC you will not.
This was a smart move by BNSF. They are getting better locomotives for the same price as an six axle DC.
GP40-2 CAZEPHYR: I don't think the four axles pull as well as a regular DC unit with six axles at slow speeds but they do better at high speed for stack trains. CZ The ACs will pull better at low speeds too. At slow speeds, the DCs are going to have thermal limits that the ACs will not. The ACs, being frequency driven, will also have a much higher adhesion factor.
CAZEPHYR: I don't think the four axles pull as well as a regular DC unit with six axles at slow speeds but they do better at high speed for stack trains. CZ
I don't think the four axles pull as well as a regular DC unit with six axles at slow speeds but they do better at high speed for stack trains.
CZ
The ACs will pull better at low speeds too. At slow speeds, the DCs are going to have thermal limits that the ACs will not. The ACs, being frequency driven, will also have a much higher adhesion factor.
-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/)
I agree with your comments, but I was talking about the new BNSF C4 4 axle version compared to a six axle DC locomotive. The C4's have only four traction motors on a C-C truck set and that limits their TE. They do lug better up to their limits. There have some stalls with C4's on drag trains which they were not designed for. Their primary use should be in high speed stack trains on the Transcon. The orginal GE ad talked about their design and way the BNSF wanted the high horsepower per axle.
CAZEPHYR I don't think the four axles pull as well as a regular DC unit with six axles at slow speeds but they do better at high speed for stack trains. CZ
Both GE and EMD would like nothing better than to build all AC traction locomotives now. It would simplify their manufacturing process, and AC traction in locomotives are now a proven, and very reliable technology.
There is simply no economic, and certainly no performance reason to justify new DC traction locomotives now.
DC traction motors are a technology whose time has passed.
The assumption that GE is desiring to only build AC traction locos may come from several reasons. These assumptions may also apply to EMD especially with their sale to CAT.
1. Some or all of manufacturing equipment for DC specific parts may be coming to the end of its useful or commercial life. Reducing the demand on that equipment may advoid the need to replace that manufacturing equipment if only replacement DC parts need production.
2. AC only may speed up allow # of units built to rise?
RRs going only to new AC may also have some items.
3. Cost.
4. Lower mtce costs for AC equipment especially traction motors.
5. Much of the DC overhaul equipment may be reaching the end of useful life so buying new AC specific equipment may make long term sense. Remaining DC equipment use will gradually decrease as DC locos are retired.
6. Amtrak may be a prime example of DC overhaul equipment wearing out now. The E-60s , then AEM-7DCs have been around a long time. They modified some AEMs to AC reducing DC overhaul equip useage. Acelas and HHP-8 also slowed useage. The overhaul equipment at Beech Grove for all the DC diesels may also be wering out.
7. Each major RR may be at a different point in overhaul equipment useful life remaining. It may be BNSF has Rather old overhaul equipment?
8. CN on the other hand may have rather new equipment?
Comments??
jrbernier The 'cost' of these units is the same or less than a comparable DC unit. This was the 'selling' feature that GE is offering. GE want to only build AC units. They are wired so that the missing electrical/traction motors can be retrofitted if the customer desires. The 'lift' feature does not lift the center idler axle free of the rail(this would put all the weight on the powered axles and exceed the axle loading limits - damaged rail). It lifts the axle enough to 'load' the powered axles to the maximum axle loading limit to increase adhesion at low speed. These engine do not generate the same low speed continuous TE as a normal AC GEVO, bu they are better than a DC GEVO. Considering that they cost the same as a DC GEVO - I can understand BNSF's purchase. Jim
The 'cost' of these units is the same or less than a comparable DC unit. This was the 'selling' feature that GE is offering. GE want to only build AC units. They are wired so that the missing electrical/traction motors can be retrofitted if the customer desires. The 'lift' feature does not lift the center idler axle free of the rail(this would put all the weight on the powered axles and exceed the axle loading limits - damaged rail). It lifts the axle enough to 'load' the powered axles to the maximum axle loading limit to increase adhesion at low speed. These engine do not generate the same low speed continuous TE as a normal AC GEVO, bu they are better than a DC GEVO. Considering that they cost the same as a DC GEVO - I can understand BNSF's purchase.
Jim
I was not aware that GE might offer these for about the same money as a DC unit. The weight that is lifted off of the center axle is probably about 20% of that axle weight but it does allow the two other axles to gain traction below 12 mph. I don't think the four axles pull as well as a regular DC unit with six axles at slow speeds but they do better at high speed for stack trains.
There was a GE ad about these locomotives for a time on their web page.
Modeling BNSF and Milwaukee Road in SW Wisconsin
Andrew Falconer How much do they cost per unit compared to other models? Andrew
How much do they cost per unit compared to other models?
Andrew
They are AC units so the cost is probably about the same as other AC units, which cost much more than the DC units. Sorry I have no exact figures, but maybe the GE web site could give you some information. The lack of two traction motors might be a slight reduction, but these units have the special lifting devices for the center axle in each truck that probably adds cost equal to the missing traction motors.
The center axle has mechanical devices operated by air and controlled by the computer that lifts the center axle on startup if more traction is required. This is deactived above 12 mph so it is just for start up only. Interesting to hear them when they are in this mode.
The C4's have 1100 hp per axle and were purchased for cross country stack service, not drag freight.
The old 500 series B alxe GE's used to be used on the high speed Z trains much of the time since they had a higher ratio of HP to axle than the C truck GE's..
One roster-like website lists BNSF as having over 200 more ES44C4's on order, with some being delivered now.
http://www.dieselshop.us/BNSF.HTML
Numbers ordered are 6653-6879 (227 units).
For that quantity of units on a single ordered, the model must be proving to be a winner on BNSF!
On April 9, 2011 BNSF ES44C4 unit 6665 (above) was photographed in DPU mode at Hesperia, CA on the eastern slope of Cajon Pass.
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