A well designed 4-8-4 would maintain its starting tractive effort up to between 15 and 20 MPH.
A Santa Fe 3765, 3776 or 2900 class would be putting out considerably more than 36000 lbs TE at 35 MPH.
Most other big 4-8-4s would do the same.
I used the ATSF engines because one of the routes discussed was a historical Santa Fe routing.
What killed steam was maintenance costs and availability, compared with diesels.
Individual diesel units at the time they replaced steam were relatively small and produced far less horsepower than the steamers they displaced.
It took many decades before a single diesel unit could produce horsepower comparable to that of a single NKP Berkshire (4500 cylinder HP).
daveklepper The ACL frequenctly used Pacifics, passenger power, for 60 and 70 refer-car hot shot freights. Track speed was 79 during Amtrak-SCL days days but there were spots of 90 and perhaps 100 earlier.
Dave, you're right about the ACL's allowing 100 mph between Richmond and Jacksonville--and it was not just in spots. There was an article in Trains back in the sixties (Paul North may be able to tell us what issue) which covered the main line operation. I found it fascinating. Back then, the Coast Line was advertising that it could take you from New York to Florida without the possibility of a detour by way of Cuba. Some of the ads pointed out that these trains were faster than those of the road that went "Through the Heart of the South," even though the Richmond-Jacksonville route via the JSL cutoff was only about twelve miles longer.
Johnny
Thanks for the data, Don!
And, Pennsy, thanks for your info, too. I understand that the new rebuilt AEM-7 "AC" units can pull as much as two unrebuilt units now.
aegrotatio Does Metra's F40PH units have a dedicated engine powering the HEP? I thought the newer (possibly rebuilt) units have dedicated engines for HEP.
Does Metra's F40PH units have a dedicated engine powering the HEP? I thought the newer (possibly rebuilt) units have dedicated engines for HEP.
Boston's MBTA used F40PH built like Amtrak. To maintain HEP in stations and between runs it was required it to have a "Fast Idle" speed. (noise and smoke). The next order was for F40 PHL (L for long). The longer Carbody not only looks better but houses a separate diesel for HEP, and gives the locomotive a standard 8 notch throttle.
Don U. TCA 73-5735
In advance of the person with the real answer (Pennsy 4430), having ridden the ACL main over 100 times, I'd say you are correct. Pretty flat with no real steep grades. The ACL frequenctly used Pacifics, passenger power, for 60 and 70 refer-car hot shot freights. Track speed was 79 during Amtrak-SCL days days but there were spots of 90 and perhaps 100 earlier.
pennsy4430That diesel was slow to accelerate but once up to speed cranked right along at track speed, hardly lost time.
Would it be too much to guess that there were not many steep up slopes?
timzPaul MilenkovicDo you mean to tell me that a booster-equiped Northern is a match for a pair of Genesis locomotives?The 4-8-4 would produce the same tractive effort at 5-10 mph that the two P42s produce at 30-35 mph. If that means it's matching them, then maybe so. The P42 weighs... at least 270,000 lb? So we could hope adhesion would allow more than 36,000 lb continuous TE, despite the monocoque frame; the low rating is the disadvantage of gearing all the P42s for the same maximum speed (110mph?).
Paul MilenkovicDo you mean to tell me that a booster-equiped Northern is a match for a pair of Genesis locomotives?
The P42 weighs... at least 270,000 lb? So we could hope adhesion would allow more than 36,000 lb continuous TE, despite the monocoque frame; the low rating is the disadvantage of gearing all the P42s for the same maximum speed (110mph?).
-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/)
I am a retired Amtrak engineer. Worked the Northeast Corridor for most of my 33 yrs but moved to Myrtle Beach in 1998. I then learned the CSX RR from Washing ton South to Savannah ,Ga. and ran my final 5 yrs there. Have been retired now for 7 yrs.
I noticed that no one person mentioned another theory of the 2 locos with 7-10 cars. They may be deadheading that 2nd loco West somewhere cause of a shortage of power. Certainly I am not familiar with rails West of Washington or New York, So not sure of how much power are used on the Trains.
Generally on the Corridor, an Aem 7 was good to haul about 10 cars max then they added a 2nd loco. Schedule was everything, on time or the dispatchers were on your case. Csx was not that concerned with the schedule just keep out of the way of of there hot shots which is understable.
One Thanksgiving I went on duty to return South from Richmond, VA. to Florence, SC. The train came in with 23 cars and a bad lead unit. We tryed to multiple a freight loco in front of the 2nd Genesis but could not get the air to work( 3 engineers and a road foreman tryed lol). So i was ordered South with 1 Genesis and 23 cars. Surprised me! That diesel was slow to accelerate but once up to speed cranked right along at track speed, hardly lost time.
Enough war stories for now. Hope I have answerd in another way your question. For all who read this on 12/12, have a great holiday -- Herb Alban
blue streak 1 If there is either the 9 or 10 car limitation on one HEP power source or not beirg able to parallel the outputs please explain AMTRAK's Auto Train consists.??
If there is either the 9 or 10 car limitation on one HEP power source or not beirg able to parallel the outputs please explain AMTRAK's Auto Train consists.??
I believe Amtrak has a 14 car limit on HEP.
Paul Milenkovic I think the answer is 1) enough locomotive units to handle ruling grades without having to assign helpers, 2) the high gearing of the P42's and use of DC traction motors means, perhaps, half the tractive effort of a comparable freight locomotive unit, 3) enough power to get the acceleration required to keep schedules, and 4) some degree of redundancy as it isn't just mechanical failure to worry about, there is a high chance of a grade crossing collision stranding a train.
I think the answer is 1) enough locomotive units to handle ruling grades without having to assign helpers, 2) the high gearing of the P42's and use of DC traction motors means, perhaps, half the tractive effort of a comparable freight locomotive unit, 3) enough power to get the acceleration required to keep schedules, and 4) some degree of redundancy as it isn't just mechanical failure to worry about, there is a high chance of a grade crossing collision stranding a train.
The P42s would only be 2/3rds the TE of a typical DC motored freight locomotive like a Dash-9 if they had freight gearing, then toss in the effects of the 110 mph gearing and I think they have 40% or less, at useable speeds.
If GM "killed the electric car", what am I doing standing next to an EV-1, a half a block from the WSOR tracks?
A bad week for the WB "Empire Builder": Fri, 20 Nov it hit a van parked, on the tracks, between Cut Bank and Browning, MT. Railroad-assisted suicide attempt? #7 was only seven minutes late into SEA. Next day they hit a trespasser in the same area. Dunno how it affected the sked. On Wed, 26 Nov they hit a boulder on the rails just west of Essex, MT. Derailed the lead wheelset. Lost about six hours while BNSF re-railed the loco. Good job, guys! That "second" unit gives some peace-of-mind, especially if it is facing the right direction.
Hays
Re: CPR E-8s -- I knew that! "It was just a typo!".
Wish I could figure out how to 'snip' and 'quote' to shorten the reply.
timz Paul MilenkovicDo you mean to tell me that a booster-equiped Northern is a match for a pair of Genesis locomotives?The 4-8-4 would produce the same tractive effort at 5-10 mph that the two P42s produce at 30-35 mph. If that means it's matching them, then maybe so. The P42 weighs... at least 270,000 lb? So we could hope adhesion would allow more than 36,000 lb continuous TE, despite the monocoque frame; the low rating is the disadvantage of gearing all the P42s for the same maximum speed (110mph?).
Granted that does play to it, these things are sometimes as slippery as a Pennsy T-1.
Of course E7's had only 2000hp and E8's 2250, so not too surprisingly, some trains used 2 or more units.
C&NW, CA&E, MILW, CGW and IC fan
BNSFwatcherGot thinking about it a bit more. In the "olden days", AT&SF ran with four Fs on their passenger trains. Ditto UP, unless E's were available. CPR always added a unit, or two, to the westbound Canadian at Calgary. GN ran with four Fs over Maria's Pass. Even NYC used three E7s on some trains on the "Water Level Route". Don't see many pictures of LD passenger trains with only one unit. Perhaps the CPR's "Alouette", with one E8, but they only had one! SAL and ACL regularly ran with three units. Please don't mention the RI. That was another type of animal... Hays
Got thinking about it a bit more. In the "olden days", AT&SF ran with four Fs on their passenger trains. Ditto UP, unless E's were available. CPR always added a unit, or two, to the westbound Canadian at Calgary. GN ran with four Fs over Maria's Pass. Even NYC used three E7s on some trains on the "Water Level Route". Don't see many pictures of LD passenger trains with only one unit. Perhaps the CPR's "Alouette", with one E8, but they only had one! SAL and ACL regularly ran with three units. Please don't mention the RI. That was another type of animal...
Actually CPR had three E8s, but in the pictures I have seen of the Montreal-Boston train there was only a single E-unit, either a B&M E7 or a CPR E8, on the front. Of course the E-units had two diesel prime movers inside that carbody so the train was in some respects run with "two" engines. One of the trio was retired about 1969 following a head-on collision, the other two lasted into the VIA ownership.
In the early 1970s the Toronto-Sudbury section of "The Canadian" would often run with a single F-unit or FPA-2. The Montreal-Saint John "Atlantic Limited" also commonly used just a single unit, mostly an F-unit but for a time an E8 was the standard power.
John
Paul Milenkovic oltmanndHere's how it works. Start with the schedule, complete with stops. Figure out how much HP you need to get the train over the road on that schedule plus some padding for service reliability. You can do this by trial and error with actual operation or by simulation. For most Amtrak trains, you'll wind up in the 6-8 HP/ton range. Now, take a typical Amtrak train of 10 cars or so at 70 tons each plus a locomotive or two at 135 tons each. That's about 1000 tons. One P42 = 4.2 HP/ton (closer to 3.5 HP/ton with HEP accounted for). Not enough. Two P42s = 8.4 HP/ton (7.5 HP/ton with HEP). Bingo! Two P42s are needed. Could you run the train with one P42? Most likely, yes, you'd get there, but, you'd be late at destination more often (maybe even all the time). There is one added wrinkle. The TE at minimum continuous speed for a P42 is about 36,000#. The max ruling grade for one P42 with a 1000 ton train would be 1.8%. That would be OK from trains in the east that don't go over the Alleghenies. like the Florida trains, the Crescent and the City of New Orleans, but not for most of the western trains, so two are needed to keep from stalling. In fact, two P42s on the SW Chief would be cutting it kind of close for Raton, so three are a safe bet. Only 36,000 lbs tractive effort without burning out the traction motors? Do you mean to tell me that a booster-equiped Northern is a match for a pair of Genesis locomotives? I thought that with wheel slip control and improved electrical insulation materials that a B-B locomotive could do much better. Is this figure on account that the P42 is geared for a high top speed and it has DC traction motors? Would an AC-motored passenger locomotive result in "unit reduction" on Amtrak?
oltmanndHere's how it works. Start with the schedule, complete with stops. Figure out how much HP you need to get the train over the road on that schedule plus some padding for service reliability. You can do this by trial and error with actual operation or by simulation. For most Amtrak trains, you'll wind up in the 6-8 HP/ton range. Now, take a typical Amtrak train of 10 cars or so at 70 tons each plus a locomotive or two at 135 tons each. That's about 1000 tons. One P42 = 4.2 HP/ton (closer to 3.5 HP/ton with HEP accounted for). Not enough. Two P42s = 8.4 HP/ton (7.5 HP/ton with HEP). Bingo! Two P42s are needed. Could you run the train with one P42? Most likely, yes, you'd get there, but, you'd be late at destination more often (maybe even all the time). There is one added wrinkle. The TE at minimum continuous speed for a P42 is about 36,000#. The max ruling grade for one P42 with a 1000 ton train would be 1.8%. That would be OK from trains in the east that don't go over the Alleghenies. like the Florida trains, the Crescent and the City of New Orleans, but not for most of the western trains, so two are needed to keep from stalling. In fact, two P42s on the SW Chief would be cutting it kind of close for Raton, so three are a safe bet.
Only 36,000 lbs tractive effort without burning out the traction motors? Do you mean to tell me that a booster-equiped Northern is a match for a pair of Genesis locomotives?
I thought that with wheel slip control and improved electrical insulation materials that a B-B locomotive could do much better. Is this figure on account that the P42 is geared for a high top speed and it has DC traction motors? Would an AC-motored passenger locomotive result in "unit reduction" on Amtrak?
There is a trade off here. The locomotive's monococque body saves fuel since its construction makes for a much lighter locomotive, but........the loss of weight drops the factor of adhesion, hence the numbers supplied above.
And no, with maintenance, water and fuel stops and other variables such as required facilities and materials factored in, a booster equipped Northern still isn't a match for a pair of P42's in cost or efficiency, no matter what the tractive effort is.
The "Empire Builder" has run with eleven cars for the past few years, 365. One is a baggage car, which doesn't require much HEP. Sometimes there will be PVs attached, too, especially in the summer. Sometimes there will be a car going to/from CHI, probably to Beech Grove. I have only been on it, west of Spokane once and am ashamed to say that I didn't notice how many units were on it, SPK-PDX or SEA-SPK. I do feel reassured with the "extra" power, for protection or a unit being disabled due to our numerous grade crossing incidents. My engineer neighbor said that he hit seventy antelope one day, but there was no damage to the locos. In the "old days", three run-through F40s were the rule, especially in the winter. Interesting thread, methinks....
CG-RiderIMO, as well, SouthWestChief wouldn't make it over Raton or Glorietta with only 2 units and its average 9 cars consist.....to say nothing of Cajon.
IMO, as well, SouthWestChief wouldn't make it over Raton or Glorietta with only 2 units and its average 9 cars consist.....to say nothing of Cajon.
Looking at photos in New Mexico around Raton of the Chief from 2003 onwards, it looks like it ran in 2003 with a consist of 8 cars + a baggage car, but additionally had about 10 container cars or MHC's and 3-4 P 42's. More recently no freight/express, 8 Superliners + baggage and only 2 P 42's.
Hi,
Just a small correction, if I may... BUILDER runs with 2 units ex Chicago ( and certainly needs them....) with an average consist of 10-11 cars. The power does NOT split at Spokane.
The power might CHANGE...but the Seattle section, now averaging 6 cars, still has two units; and the Portland section has one...and quite often 2, for its own 4-5 cars average
Of course, the Zephyr has a perfect mid-point stop....: Denver, where adding a third unit to a westbound consist exceeding 8 cars is a must...otherwise, the D&RG route and Donner pass will doom its timekeeping ( and might give you an experience in stalled trains....)
Just my opinion
Cheers
Sawtooth500Still, most of that stuff doesn't make sense to me....Cal Zephyr: 2-3 Genesis locs (8000-12,000 hp?) 10 cars @ 74 tons per Superliner = 740 tons. + engine weight (122 tons X 2-3 = 244 - 366 t) = 988 - 1106 tons. 4 sleepers X 35 passengers = 70; 5 coaches at 90 per car = 450; total = 520, top speed 110 mph?First off, to the best of my knowledge except on the Northeast Corridor, the max operating speed for most Amtrak as limited by tracks is 80 mph (or 79, if you insist). I do believe that certain trains, such as the Southwest Chief, do hit 90 at times because some of the track they run on is Class 5 track. I was talking with an Amtrak engineer once and I asked him the locomotive question, he didn't know the definite answer, but he did say that sometimes the Southwest Chief will operate on one engine, it just take a while to get to 90 on one engine, but you'll still get there. I don't believe the California Zephyr goes any faster than 80. Amtrak has fuel saving instructions in place and locomotive assignments are a function of a combination of things: fuel consumption, power requirements, HEP eliability, grades and train weight. One item not mentioned is the fact that the P42's are much lighter than freight locomotives of the same horsepower rating and are therefore, a little more slippery with a poorer factor of adhesion. The fact that the locomotives are geared for passenger speed reduces the power output at the rail in terms of acceleration, i.e, these engines are built for speed, not lugging ability and as such are much more sensitive to train weight.Locomotive failure, schedule demands, and its Amtrak...Regarding locomotive failure, wouldn't it be cheaper just to have better maintenance than it would be two run another locomotive? Not to mention all the money you'd save for new routes if they didn't have to buy new locomotives... And regarding schedule demands, well if only 1 loco was scheduled and they had another free one, wouldn't this make the schedule more flexible? Scheduling 2 locos puts more strain on the schedule, not less....Locomotive maintenance is an issue on all railroads, and as it goes, Amtrak does a pretty respectable job of maintaining what can be considered an elderly fleet. The schedule is what it is, and the power assigned is based upon many factors, both permanent and temporary, schedule being just one part of the equation.The Empire Builder is pulled by two locomotives from Chicago to Spokane, where the train is split into Portland and Seattle sections. One locomotive is used to power the Portland section, whilst the other powers the Seattle section. Now that kind of makes sense, if they are going to be spilling the train, but wouldn't it be cheaper just to store a locomotive in Spokane instead of running it every time to Chicago and back?The Builder contends with one of the toughest grades in Montana and two units are needed to power the train on that grade and maintain that nasty old schedule. Remember, HEP reduces the second unit's traction output considerably, more than the 700 hp quoted elsewhere.Don't forget that as much as 700hp. is diverted to providing hotel power to the train. Then you have situations like on the climb out of the Colorado River basin to the top at Yampai Summit, over 100 miles of near steady 1.4% which all but the hottest freights climb at 25 - 30 mph. and Amtrak climbs at 70 mph. And then consider on a route like that if you lose a Diesel you have no AC in the summer and no heat in the winter if you have only one locomotive.Don't all passenger locomotives have head end units which provide the electric power for the train? And those units are separate from the prime mover, correct? I know that if you look through the back door of a genesis loco you see a second, smaller diesel in the back room. Also, regarding speeds through the mountains, if a helper loco is truly needed to maintain speed on a grade, wouldn't a helper district make much more sense than running the locomotive the whole distance to and from Chicago?Head end power as provided by an Amtrak P42 reduces the horsepower available for traction by considerably more than the 700 hp quoted above. What you see in the back is in fact the air compressor and its components and a small generator which develops HEP off the prime mover. There is no auxiliary diesl engine on a P42.FYI I'm not trying to offend anyone for the posts and thank you very much for giving feedback, I'm just playing devil's advocate here, and I'm trying to find the correct answer!
Cal Zephyr: 2-3 Genesis locs (8000-12,000 hp?) 10 cars @ 74 tons per Superliner = 740 tons. + engine weight (122 tons X 2-3 = 244 - 366 t) = 988 - 1106 tons. 4 sleepers X 35 passengers = 70; 5 coaches at 90 per car = 450; total = 520, top speed 110 mph?
Amtrak has fuel saving instructions in place and locomotive assignments are a function of a combination of things: fuel consumption, power requirements, HEP eliability, grades and train weight. One item not mentioned is the fact that the P42's are much lighter than freight locomotives of the same horsepower rating and are therefore, a little more slippery with a poorer factor of adhesion. The fact that the locomotives are geared for passenger speed reduces the power output at the rail in terms of acceleration, i.e, these engines are built for speed, not lugging ability and as such are much more sensitive to train weight.
Locomotive failure, schedule demands, and its Amtrak...
The Empire Builder is pulled by two locomotives from Chicago to Spokane, where the train is split into Portland and Seattle sections. One locomotive is used to power the Portland section, whilst the other powers the Seattle section.
Don't forget that as much as 700hp. is diverted to providing hotel power to the train. Then you have situations like on the climb out of the Colorado River basin to the top at Yampai Summit, over 100 miles of near steady 1.4% which all but the hottest freights climb at 25 - 30 mph. and Amtrak climbs at 70 mph. And then consider on a route like that if you lose a Diesel you have no AC in the summer and no heat in the winter if you have only one locomotive.
Sawtooth500 That makes sense if you need two HEP units for 9 and more cars... but now the business man in me asks... wouldn't it not make more sense for Amtrak to simply upgrade the HEP unit to output more power? I'm sure that upgrading the HEP in the long run would cost a lot less than operating a second diesel on 2 thousand mile trips just for a second HEP...
That makes sense if you need two HEP units for 9 and more cars... but now the business man in me asks... wouldn't it not make more sense for Amtrak to simply upgrade the HEP unit to output more power? I'm sure that upgrading the HEP in the long run would cost a lot less than operating a second diesel on 2 thousand mile trips just for a second HEP...
No additional locomotives for HEP, only one locomotive can supply the HEP otherwise they would have to be synchronized (which is difficult on a locomotive with its variable power demands). But if the locomotive supplying HEP dies you have to have another that can be cut in.
Sawtooth500Still, most of that stuff doesn't make sense to me....Cal Zephyr: 2-3 Genesis locs (8000-12,000 hp?) 10 cars @ 74 tons per Superliner = 740 tons. + engine weight (122 tons X 2-3 = 244 - 366 t) = 988 - 1106 tons. 4 sleepers X 35 passengers = 70; 5 coaches at 90 per car = 450; total = 520, top speed 110 mph?First off, to the best of my knowledge except on the Northeast Corridor, the max operating speed for most Amtrak as limited by tracks is 80 mph (or 79, if you insist). I do believe that certain trains, such as the Southwest Chief, do hit 90 at times because some of the track they run on is Class 5 track. I was talking with an Amtrak engineer once and I asked him the locomotive question, he didn't know the definite answer, but he did say that sometimes the Southwest Chief will operate on one engine, it just take a while to get to 90 on one engine, but you'll still get there. I don't believe the California Zephyr goes any faster than 80.Locomotive failure, schedule demands, and its Amtrak...Regarding locomotive failure, wouldn't it be cheaper just to have better maintenance than it would be two run another locomotive? Not to mention all the money you'd save for new routes if they didn't have to buy new locomotives... And regarding schedule demands, well if only 1 loco was scheduled and they had another free one, wouldn't this make the schedule more flexible? Scheduling 2 locos puts more strain on the schedule, not less....The Empire Builder is pulled by two locomotives from Chicago to Spokane, where the train is split into Portland and Seattle sections. One locomotive is used to power the Portland section, whilst the other powers the Seattle section. Now that kind of makes sense, if they are going to be spilling the train, but wouldn't it be cheaper just to store a locomotive in Spokane instead of running it every time to Chicago and back?Don't forget that as much as 700hp. is diverted to providing hotel power to the train. Then you have situations like on the climb out of the Colorado River basin to the top at Yampai Summit, over 100 miles of near steady 1.4% which all but the hottest freights climb at 25 - 30 mph. and Amtrak climbs at 70 mph. And then consider on a route like that if you lose a Diesel you have no AC in the summer and no heat in the winter if you have only one locomotive.Don't all passenger locomotives have head end units which provide the electric power for the train? And those units are separate from the prime mover, correct? I know that if you look through the back door of a genesis loco you see a second, smaller diesel in the back room. Also, regarding speeds through the mountains, if a helper loco is truly needed to maintain speed on a grade, wouldn't a helper district make much more sense than running the locomotive the whole distance to and from Chicago?FYI I'm not trying to offend anyone for the posts and thank you very much for giving feedback, I'm just playing devil's advocate here, and I'm trying to find the correct answer!
There are two primary methods for providing hotel power to a passenger train. the first is to draw it off of the locomotive's main alternator(which O.C does mean less power is available for the traction motors) and IINM this is the method most if not all of Amtrak's diesel fleet uses. The second method is to have an auxiliary diesel electric genset on the locomotive (or in some cases in a head end generator car). This is very common on commuter railroads. My understanding is that an HEP genset can save significant amounts of fuel in services where the train starts and stops frequently i.e commuter service..
"I Often Dream of Trains"-From the Album of the Same Name by Robyn Hitchcock
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