EMD SD70ACe-P4 for BNSF

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EMD SD70ACe-P4 for BNSF
Posted by YoHo1975 on Thursday, January 26, 2012 12:42 PM

My trains subscription expired so I can't get to the newswire, but yesterday it was announced that EMD is making a new model of the 70ACe to compete with the GE C4 models.

 

The difference is that these models will use B1-1B trucks.

Anyone know why? is bogie engineer still around? I've anecdotally heard that it's because EMD's radial truck is so much better that they don't need to raise and lower that center axle, but that doesn't explain why a B1-1B makes sense vs. A1A. Plus, the Radial truck costs more, these could be the rigid truck.

I'm assuming that the bogie itself is no different than the current model. Is this true or is it a new bogie?

 

 

Also, BNSF bought these C4s to get off of DC locos in their non-drag trains aka stack and general freight. BNSF and it's predecessors haven't bought an EMD for this purpose since ATSF's SD75s have they? They've been GE only for all but Coal for over 15 years. I wonder what has changed to make them bring EMD back into this?

 

Maybe as simple as a cost issue? This change brings the cost down. Or maybe EMD is being more aggressive in pricing (which would dovetail nicely into the fight over salaries at the factory.

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Posted by Leo_Ames on Thursday, January 26, 2012 2:14 PM

They'd still be raising an axle on each truck, just not the center axle. So I don't see what that has to do with the superiority of one truck design over another. I'm not an engineer so I won't venture to guess why they went with this design, but it's safe to assume it's being done because EMD feels like the axle closest to the fuel tank on each truck is the best choice to leave unpowered.

 I think it's safe to assume the trucks will be similar to those that other SD70Ace's roll on, just with the necessary modifcations (Just like GE's C4 model). BNSF has only recieved SD75M's and SD75I's for EMD DC units.

BNSF has over 1000 SD70MAC's/SD70Ace's. And they're also pleased with GE's C4 project. Not a shock that they'd be curious enough to place an order for a comparable EMD model that is largely identical to their several hundred SD70Ace's already rolling around the system. If they're unhappy with their performance and decide to stick exclusively with GE's C4's for new orders, they can probably easily convert them into full fledged CC's without much trouble.

You typically see a big company like BNSF trying to keep the builders honest and encourage them to keep innovating. A small order for a new model utilizing a concept that intrigues BNSF that has a high degree of parts commonality with existing units on the roster isn't too big of a shock (10 units and 4 conversions isn't anything Earth shattering on a roster the size of BNSF's). Will be interesting to see if this leads to large orders on a road with 1700 or so C44-9W's, over 700 ES44DC's, and 300 C4's for the roles this design is intended to fill.

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Posted by YoHo1975 on Thursday, January 26, 2012 4:22 PM

All the information I've seen says that the EMD system will not raise and lower the idler axle. 

 

Also, as for not favoring GE over EMD. First I made it clear I was speaking of Non-AC units so Stack train power. BNSF has made it clear since the merger that it had not interest in EMD for this purpose.

 

Secondly, even ignoring this, BNSF currently rosters 2900+ Dash 9-44CW/ES44DC/AC4400CW/ES44AC. That doesn't include the 4 axle GE units or the Dash 8s.

More than 2200 of those are DC units. Dash 9s and ES44DCs.

 

They roster 1159 EMD SD70MAC/ACe/SD75s of those, many of the MACs are stored and only 102 of them are DC units regularly used on stack trains.

 

The facts simply do not show that BNSF doesn't favor GE. They absolutely favor GE.

And that makes it a big change that they would look to EMD for general freight power.

 

All I can think is that EMD has either changed pricing, they really really like their ACes or, and I find this most likely, They've always preferred EMD's AC units and now that they're going all AC, their preference for GE DC units falls away. 

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Posted by BaltACD on Thursday, January 26, 2012 4:54 PM

More likely they want to give EMD enough business so that they stay in business.  The Class I carriers want some competition for their purchases and will make some 'mercy purchases' just to keep a company in business even though they may not be the preferred provider of the product.

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Posted by YoHo1975 on Thursday, January 26, 2012 5:57 PM

But what sense does that make?

EMD doesn't seem to be hurting for orders. Union Pacific, KCS, NS and Canadian National place orders with them. Why would BNSF feel the need to protect a second source for a source that doesn't appear to be struggling to generate orders.

To say nothing of the overseas and south american orders.

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Posted by efftenxrfe on Thursday, January 26, 2012 7:08 PM

Protecting EMD?  What EMD: GM/EMD or  Caterpillar/Progressive/EMD? Cat-P-EMD just reported hugely improved earnings. 

The B1-1B does give me pause-time.  Would any steam locomotive with an 042-240 arrangement been designed?  The non-driving axles guiding ability would seem likely......Locomotive engr,  not a mech engr.

Also, minutely, saving a little, .very little rail abrasion would probably occur with the inboad powered axles placement.

 

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Posted by creepycrank on Thursday, January 26, 2012 8:23 PM

EMD did build some WDP-4GT46PA's with the B1-1B wheel arraignment in 2001 for the Indian Railways so they do have some experience with it.

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Posted by beaulieu on Friday, January 27, 2012 7:26 AM

The first SD70ACe-P4 has hit the road, EMD test locomotive 4223 has been photographed after being released from Muncie.

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Posted by YoHo1975 on Friday, January 27, 2012 12:17 PM

From the picture linked to in Loconotes, the bogies look to be the standard HT-CR or whatever the base designation is for the modern truck. 

 

Also, from Tom Mack on loco notes


It has to do with the design of the EMD HTC and HTC-R truck. When the truck flexes under load (torque) you actually get better adhesion with the B1 design vs. A1A on this particular truck.

Also, note that the wheel arrangement would be as stated in the Trains magazine article, B1-1B, not B1-B1 as stated in some earlier posts. This is becuase all the traction motors face inward toward the fuel tank on EMD C-C locomotives using the HTC and HTC-R trucks. So it is the inboard motor that is removed to create the B1 truck, and since the trucks mount in opposite directions at each end of the locomotive you get a B1-1B wheel arrangement.

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Posted by Leo_Ames on Saturday, January 28, 2012 3:46 AM

The Trains news piece made it sound like it was a copy of the GE concept. Interesting if accurate that they're not raising an axle.

That could mean savings, both in initial cost and maintenance expense over the years with a simpler truck arrangement  (And possibly even easier conversion to CC units if desired in the future?).

For a road that is already experienced and like's EMD's AC products that has dropped the cash for 300 hundred examples of the comparable GE model to this new EMD concept over the past few years, I don't see anything to be puzzled about here. This looks more than worthy of exploration on the part of BNSF.

Let's hope it succeeds. EMD is still pretty far behind GE in orders. If I'm not mistaken, there are only about 1,500 of EMD's SD70ACe/M-2's rolling around out there worldwide while there are more ES44AC/C4/DC's than that just on BNSF's roster alone.

 

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Posted by EMD#1 on Monday, January 30, 2012 1:00 PM

More than likely BNSF is testing these units in direct comparison with the GE C4 units.  They will look at a number of factors to determine future orders.  You can bet if the tractive effort, rail adhesion and fuel consumption are on par or superior with the GE C4 models, BNSF will be back for more.

On a side note I just had the chance to operate two of our new Norfolk Southern SD70ACe units on a loaded 60 car ethanol train.  I was very impressed with their performance on this 8,000 ton train compared to running the same train with a couple of GE DC engines.  I also appreciated that they had an isolated cab which made them as quiet as a GE on the inside, something our M-2 locos lack.

 

TBG

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Posted by YoHo1975 on Monday, January 30, 2012 1:38 PM

If I recall correctly, the initial order for C4s was 10 as well. So that number isn't surprising.

 

My surprise was more the apparent change in attitude about EMD in general. BNSF made it clear they had no use for EMD's DC products for over 15 years now. Clearly the move to all AC is changing that. 

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Posted by creepycrank on Monday, January 30, 2012 8:06 PM

The efficiency of DC transmission is 85% and the same locomotive with AC will be about 94% so in high speed service where they burn a lot of fuel it will save a lot of money.

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Posted by a#1beau on Monday, January 30, 2012 11:02 PM

EMD will never -- repeat N-E-V-E-R -- regain its dominance as number 1 diesel locomotive builder again.  GE has already sworn to this.  In thirteen more years, GE will have been the market leader for as long as EMD ever was in all its history.  Thank you, Roger Smith and all your early 80's GM cronies for the death of EMD as we once knew it. 

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Posted by Leo_Ames on Tuesday, January 31, 2012 5:52 AM

Your math is a bit off. EMD was the market leader in the diesel locomotive market until the 1980's (Only being beat even then by a slight amount in 1983, 87, and 88 with EMD leading the rest of the decade and often by a substanial margin). Since then, EMD has came close to GE on at least a couple of occasions including being just a few units away a decade ago or so.

Generally 1989 seems to be viewed as when EMD's reign ended as market leader ended. That's 65 or so years of dominance with internal combusion rail power to GE's 24 or so years of dominance. And even if we just look at the introduction of the 567 at the end of the 1930's when EMC/EMD really hit the bigtime, that's a run of 50 years as the dominant leader in this marketplace.

EMD being a distant 2nd was at one time unthinkable. It's hardly a sure thing that GE's reign as market leader is permanent.

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Posted by oltmannd on Tuesday, January 31, 2012 12:08 PM

a#1beau

EMD will never -- repeat N-E-V-E-R -- regain its dominance as number 1 diesel locomotive builder again.  GE has already sworn to this.  In thirteen more years, GE will have been the market leader for as long as EMD ever was in all its history.  Thank you, Roger Smith and all your early 80's GM cronies for the death of EMD as we once knew it. 

Oh, I don't know.... I remember when Brand X was Brand X for a reason.  What goes around, comes around, they say.  Nothing would surprise me.

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

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Posted by XC Tower on Wednesday, February 08, 2012 3:40 PM

At the risk of sounding stupid (won't be the first or last), but do these units have four "B" trucks per unit or the same two "C" trucks as the GE's but with just a different unpowered axle?

 

XC Tower

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Posted by beaulieu on Wednesday, February 08, 2012 5:36 PM

XC Tower

At the risk of sounding stupid (won't be the first or last), but do these units have four "B" trucks per unit or the same two "C" trucks as the GE's but with just a different unpowered axle?

 

XC Tower

Two trucks with three axles each, just like GE. Except on the GE locomotive it is the middle axle on each truck that is unpowered, while on the EMD it is the axle closest to the fuel tank.

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Posted by EMD#1 on Friday, February 10, 2012 7:30 AM

With a higher gear ratio enabling the unit to run at higher speeds this engine would make a great long distance passenger model.  EMD locomotives load faster than GE locomotives making them quicker off the starting line and less likely to lose a lot of speed coming out of dips.  If it turns out successful on the BNSF it may be preferred power on their intermodal trains where superior train velocity means everything.

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Posted by bubbajustin on Friday, February 10, 2012 12:33 PM

If they do produc new locomotives they will be mad at Munci Indiana. good news for us foamers with a burning desire to see forgien power!

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Posted by jrbernier on Friday, February 10, 2012 2:36 PM

EMD#1

With a higher gear ratio enabling the unit to run at higher speeds this engine would make a great long distance passenger model.  EMD locomotives load faster than GE locomotives making them quicker off the starting line and less likely to lose a lot of speed coming out of dips.  If it turns out successful on the BNSF it may be preferred power on their intermodal trains where superior train velocity means everything.

  Higher gearing will produce lower axle rotation/speed.  At 200+ tons, these would not make attractive passenger engines.  The key is to keep the weight down for a passenger engine(GE had to have custom-made car bodies for the AMD-103 so they could keep the axle loading down).

  BNSF is basically getting AC drives for DC prices.  The starting TE is close to the DC 6 motor drive, and the continuous TE at track speed is higher.  And they get a parts inventory reduction as these vengines use the same AC traction motors/invertors as a normal SD70ACe.  This is why BNSF already has over 200 GE ES44C-4 engines with a similar configuration.  As far as loadinging faster, EMD products usually are faster to load up, but this is something that can be adjusted by the computer/injector settings as well.

Jim

Modeling BNSF  and Milwaukee Road in SW Wisconsin

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Posted by efftenxrfe on Friday, February 10, 2012 8:10 PM

"EMD locomotives load faster than"....another can of squirming tubular animals opened.

Bring your lunch when you start an SP E7,8 or 9.

An SP PA? Put it in run 3,from idle, and there'd be hundreds of amps in a couple of seconds.

A commute GP9: wipe the throttle,idle to run 8, full amperage  in about 8 seconds.

The FM Trainmasters were said  move out so fast that someone standing at the front end couldn"t climb on the rear-end.

The SDP-45's when used on the same schedules of the TM's took so much time transitioning that they had a switch that locked them in full-parallel. Normal FM (2400 hp) vs. SDP-45 (3600 hp) hybridized.

The LIRR demo-ed  a GP7; it dieselized with Alco's and FM's.

The P30CH's  that Amtrak leased to SP ran for me just fine on ferrying moves powering the Coast Starlight from LA to San Luis, this while remembering there was a fast- start switch on the lamented Amtrak SDP-40F's

Favorites exist, reasons for them are boundless, and here's a screw-loose admiration of EMD's "40's"

We refueled the DRG&W GP40-2,  our work train's power, and on the way back to our assignment, I said I had no idea. light engine, O k?

the question was "0 to 60 how fast?"

Independent fully applied, run 8, indepentent  released when the engine over powers the ind brake, My watch timed it at 36 seconds.

Amtrak's 200's and 300's were great, more than that DRG&W freight GP.

Smaller brush please when you paint passenger engines.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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Posted by oltmannd on Saturday, February 11, 2012 8:31 AM

The SD40-2s and SD45-2's I've tested take about 30 seconds to full load - it's controlled by the RC module.  Power comes on linearly in that time

A GE with the FDL engine and CHEC excitation with a 3 slope curve, takes 80 seconds, about half of it in the last 20 seconds.  This is controlled by CHEC which is desperately trying to avoid smoke by keeping the engines speed ahead of the load, allowing the turbo to spool up.

A B36-7 would make a horrible commuter train locomotive.  You'd be at the next stop before the engine decided it was going to actually make any HP.

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

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Posted by timz on Saturday, February 11, 2012 7:20 PM

oltmannd
This is controlled by CHEC which is desperately trying to avoid smoke by keeping the engines speed ahead of the load, allowing the turbo to spool up.

Which raises the question: did the U34CHs do any better, with their constant-speed prime movers. (Guess P42's are constant-speed too?)

As always, it's too bad US railfans have never been train-timers like they have in Europe. Would be nice to know how well FM's etc actually did.

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Posted by efftenxrfe on Sunday, February 12, 2012 9:20 PM

SP's latter U33C's came with a smoke abatement eng. speed/throttle position/performance abberation that might answer.

Recollection drives this; I can't find documentation; performance was improved but they were  Clydesdales, nothin' like a cowpony.

When you took run 1 you got run 3 engine rpm; over run 3 rpm increased to run 5; over run 5 full maximum rpm with faster loading than the standard " throttle increase, eng speed increase, load increase sequence."

Thus the U34's  probably were veritably hot-rods 'cause of their constant HEP required engine rpm.

This might entertain: SP's GP35's instantly loaded to maximum amperage when throttled up at starting a train. I've got 120 mty (you knew they had solid journal bearings....sure) at a precise West Oakland crew change point called the toe-, or tow- path: inbound you'd stretch-brake to spot your  front fireman's side steps on a 6 foot wide asphalt sidewalk crossing accessing the West Oak' Diesel Shop.

After about 10 minutes to allow this AB brake train to release I tried to get out of town, freeing up 16th St, West Oak interlock and Magnolia Tower....in other words most of the center of the center of the railroad.

.That the controlling locomotive was not modified for faster loading and was a "stock" U33C allows guesses.

Run 2 throttle, decrease independent brake, wheel spin alarm, close throttle.

"took slack...after asking the inbound crew if I can take a few cars of slack to make sure i wouldn't shove past an interlocking signal behind  me. The caboose said  OK so I tried again; WS from the GP35l long before the U33 had "rubbed the sleep out of its eyes."

Shoved back for slack more vigorously and got no further. West Oak interlock is more derisive.; other cohorts complain close by in the terminal.

I asked the my head brakeman to put the GP35 on-the-line on my signal. Back to the U33C and open throttle,wait until (about a minute) amperage is about 900, I signal my head brakeman to put th e GP35 on-the-line and we walked out of Oakland.

 

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Posted by daveklepper on Tuesday, February 14, 2012 3:41 AM

It is too bad the LIRR didn't try the GP-9.   The GP-7's tried by the LIRR must have had the passenger load regulator controls.  The alternative switcher and frieght ones for the GP-7 did load a lot faster.   My 1953 MIT thesis addressed this problem and concluded that in raising prime mover rotational speed from idle to maximum, half the torque should be used to accelerate the prime mover and half to move the train, for optimum acceleration, and without any serious loss of the smoothness characteristic of the slow loading E units other locomotives with passenger load regulators.  B&M 1567 and 1568 were equipped with experimental load regulators pretty much in accordance with this idea, which proved successful, with these GP-7's liked for passenger, freight, and switching.   So that was the success of the GP-9 load regulator.  It also was a simpler control system than previously, fewer parts on the locomotive.  I think this idea did influence subsequent EMD designs as well.  I have no idea why they did not adopt it for the later E-8's and E-9's, except possibly to insure their compatibility with the earlier E-8's and E-7's where jar-proof, jerk-proof acceleration was the major goal.

Note that the heavier the combintion of pistons and crankshaft and valves etc., the longer it will take to accelerate the prime mover.  In this respect a two-cycle engine is ahead of a four-cycle of equal horsepower.   And a lower speed engine ahead of a high-speed engine.

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Posted by oltmannd on Tuesday, February 14, 2012 7:31 AM

daveklepper

It is too bad the LIRR didn't try the GP-9.   The GP-7's tried by the LIRR must have had the passenger load regulator controls.  The alternative switcher and frieght ones for the GP-7 did load a lot faster.   My 1953 MIT thesis addressed this problem and concluded that in raising prime mover rotational speed from idle to maximum, half the torque should be used to accelerate the prime mover and half to move the train, for optimum acceleration, and without any serious loss of the smoothness characteristic of the slow loading E units other locomotives with passenger load regulators.  B&M 1567 and 1568 were equipped with experimental load regulators pretty much in accordance with this idea, which proved successful, with these GP-7's liked for passenger, freight, and switching.   So that was the success of the GP-9 load regulator.  It also was a simpler control system than previously, fewer parts on the locomotive.  I think this idea did influence subsequent EMD designs as well.  I have no idea why they did not adopt it for the later E-8's and E-9's, except possibly to insure their compatibility with the earlier E-8's and E-7's where jar-proof, jerk-proof acceleration was the major goal.

Note that the heavier the combintion of pistons and crankshaft and valves etc., the longer it will take to accelerate the prime mover.  In this respect a two-cycle engine is ahead of a four-cycle of equal horsepower.   And a lower speed engine ahead of a high-speed engine.

Both the GP7 and the GP9 had battery field excitation.  The governor pretty much called the shots on how fast loading would occur.  It had control of how and how fast the load regulator (a rheostat powered by a vane motor) moved.

I think what you are referring to is whether the load regulator when to min or max at rest.  Some locomotives had a "fast start" switch added to the control stand so that the engineer could select whether he wanted min or max on the load regulator at start.  Max was good for kicking cars, but not smooth starts. 

Without the switch, commuter engineers often learned to fool the system.  They'd sit with the train brakes applied and crack the throttle to notch one to get the load regulator up off of min, the release the brakes and away they went.  Problem was they'd also stall burn the commutators on the traction motors.

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

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Posted by EMD#1 on Tuesday, February 21, 2012 1:31 PM

Jim, others...

I don't know the exact details of the guts inside an engine to say what makes some move faster than others but I do know from daily experience running GE locomotives and EMDs the difference between the two builders.  I will admit the newer GEVO engine equipped GE engines are far superior than their predecessors when it comes to loading up and getting them to move.  You can take a Dash 8 and a Dash 9 and move the throttle from idle to run 8 and they won't load any faster than if you notched them one notch at a time at five second intervals.  On the other hand, an EMD will start loading almost immediately, especially the GP38s, GP60s and SD40-2s.  In my early career as a brakeman I've stood next to one end of a stopped GP38.  By the time the other end of the locomotive went by me from a standing start it was moving too fast to catch up!  When you kicked cars in the yard you better be close to the cut lever on the car you wanted to cut loose when you told the engineer to kick it!  

Running trains now on the mainline I've always appreciated the way the EMD engines start pulling when changing from dynamic brake to power compared to GE engines which take what seems forever to load.  When starting up the other side of a hill or grade you want to pull the slack out before it starts shoving you.  If your engines don't start loading until you're 1/2 mile up the grade you will lose speed really fast.

As far as using SD70ACe-P4 for long distance passenger trains the fact that they are a six-axle engine compared to a four-axle engine means that they can be heavier.  They don't have to have a 5000 gallon fuel tank like the freight engines do but even still I would bet with a higher gear ratio capable of 90 MPH they would outperform a GE AMD-103 or P42.  I've had EMD engines on our 60 MPH intermodals and outran the 79 MPH Amtrak Crescent with their AMD-103s a number of times, something that would have been impossible when they ran EMD F40PHs!

Tim

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RE outrunning passenger
Posted by timz on Tuesday, February 21, 2012 4:19 PM

EMD#1
I've had EMD engines on our 60 MPH intermodals and outran the 79 MPH Amtrak Crescent with their AMD-103s a number of times

Your 60 mph train outran the Crescent? Because the Crescent couldn't make 60? How many tons did you have, with what engines? Where was this?

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Posted by oltmannd on Tuesday, February 21, 2012 6:45 PM

timz

 

 oltmannd:
This is controlled by CHEC which is desperately trying to avoid smoke by keeping the engines speed ahead of the load, allowing the turbo to spool up.

Which raises the question: did the U34CHs do any better, with their constant-speed prime movers. (Guess P42's are constant-speed too?)

 

As always, it's too bad US railfans have never been train-timers like they have in Europe. Would be nice to know how well FM's etc actually did.

A couple of differences between a U34 and P42.  The U34 was allowed to make smoke, so it probably loaded faster.  CHEC with the three slope loading curve was designed to minimize smoke.  The P42 probably has a lower volume exhaust manifold, though, which gets the juice to the turbo faster, allowing faster loading.

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

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