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Diesel B-Unit Helpers for Steam Locomotives

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Posted by NWP SWP on Wednesday, January 25, 2017 12:07 PM

riogrande5761, is correct I am just looking for a prototype to justify a GS-4-B-B-B lashup but anyway it doesn't really matter after all we all fall a bit short of the prototype in model railroading! But thanks for all your replies, it has been most educational!

Steve

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Posted by riogrande5761 on Wednesday, January 25, 2017 6:04 AM

cascadenorthernrr

Hi I have an interesting question for you all. Is it possible (hypothetically speaking) for a diesel b-unit to be placed behind the tender of a steam locomotive and be operated without an a-unit? Just picture if you will the Southern Pacific Daylight rounding a curve in the mountains led by a GS-4 and followed by an Alco PB unit what a sight that would be!

B units had hostler controls so they could be moved independantly around a yard, but in Rio Grandes case, I have never seen a photo of a PB or FTB or F3/7/9B unit working behind a steam engine without an A unit.  I am not aware that any of Rio Grandes steam engines had MU controls for a diesel behind it and it doesn't seem practical to operate a B unit on the road. 

I have viewed lots of D&RGW photo's including those from the steam era and no such photo exists of what the OP is dreaming of on that RR; I haven't seen any photo's like that for SP either, which is my other favorite RR having grown up in California.

But then again, it's cascadenorthernrr's RR and he can run whatever he likes if it looks cool.  Folks come here looking for justification when none is needed.

Rio Grande.  The Action Road  - Focus 1977-1983

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Posted by Anonymous on Wednesday, January 25, 2017 5:48 AM

steemtrayn

Clinchfield No. 1, a small 4-6-0 had a hostler control from a B unit installed to control the diesels that were required to pull it's excursion trains. It is now at the Baltimore Railroad Museum, and still has the control in the cab.

 

Here is a link to the B&O RR museum's page on the subject:

http://www.borail.org/clinchfield.aspx

The article is poorly edited and jumps around alot, but the last paragraph contains the information that you want.  The control box was added sometime between November 1968 - June 1979.  The locomotive ended up with a cracked frame (June 1979).  Do not know if that was related, or just a coincidence.  Given the age of the locomotive (built 1882), it was probably just cyclic fatigue.

If you click through the museums flickr page (at the bottom of the link I posted) you will find a photo of the cab with the control box.  I would be interested to see whats in that box, to see if it could have been made with technology available in the 1940s-50s.

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Posted by NWP SWP on Tuesday, January 24, 2017 12:09 PM

I see, very interesting!

Steve

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Posted by steemtrayn on Tuesday, January 24, 2017 7:30 AM

Clinchfield No. 1, a small 4-6-0 had a hostler control from a B unit installed to control the diesels that were required to pull it's excursion trains. It is now at the Baltimore Railroad Museum, and still has the control in the cab.

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Posted by NWP SWP on Sunday, January 22, 2017 9:42 PM

Ok thank you!

Steve

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Posted by Anonymous on Sunday, January 22, 2017 9:17 AM

SouthPenn

It's my understanding that today helpers that are spliced into the train are radio controlled from the head end. 

We've come a long way.

 

Not always.  The ATSF 3751 does not have (or did not have at the time Pentrex made the video) dual controls.  They did a helicoper chase over Cajon Pass, with radio comms from the crew, and you can clearly hear the steam engineer asking the diesel (BNSF ES44AC I think, but cant remember) to adjust his throttle/dynamic brake setttings.

I have not been in the cab of the N&W 611 recently, but I know they have been working on adding PTC gear that is now required (a new turbo is being crammed in under the shroud, fortunately it doesnt show).  I do not think she has a diesel throttle (no real need) the video I linked had a diesel helper, but on her Manassas excursions there haven't been any diesel helpers (and really doesnt need one unless the tracks are wet, slight issue this past year).   611 generates 77,899lbs of tractive effort, I believe the most of any extant 4-8-4.  

I would suggest a visit to either Viginia Museum of Transportation (during excursion off season), or to Oregon Rail Heritage Center in Portland, OR, to see full sized 4-8-4s.  There is an operating GS-4 (SP 4449) in Portland, as well as SP&S 700.

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Posted by SouthPenn on Sunday, January 22, 2017 6:19 AM

It's my understanding that today helpers that are spliced into the train are radio controlled from the head end. 

We've come a long way.

South Penn
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Posted by NWP SWP on Saturday, January 21, 2017 10:33 PM

Ok thank you very much! This has been most educational!

Steve

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Posted by ATLANTIC CENTRAL on Saturday, January 21, 2017 10:18 PM

cascadenorthernrr

So true-to-prototype MU'ing is not logical but it was possible if the concept was developed further? Of course designs would have had to been changed to create the provisions for MU'ing.

 

Yes,

Understand that in the early 50's when both steam and diesel worked together, both union work rules, and railroad attitudes that to some extent extra people meant extra safety, there was no reason to develope such technology. By the time railroads were seriously concerned about labor costs, steam was gone and two men could run the head end of as much HP as the train needed, as many diesels MU'd together as needed. 

By the 50's, railroads had no interest in pulling top passenger trains with steam, and no concern for the appearance of locos pulling freight. Most early diesels that worked with steam as helpers were ABBA sets and needed their own crew anyway as they were only used for limited distances on heavy grades.

So the whole idea you propose simply did not exist in the reality of day to day railroading - until modern steam fan trip railroading, and fears that the steam loco would "fail" or need a helper.

It should also be noted, that what looks like a diesel B unit on some excursion trains is actually a Head End Power car, a generator car providing electical power to the passenger cars. It is not a locomotive at all. Many such cars have been built from old B units, old baggage cars, etc.

Remember, steam locos have no means of generating large amounts of electrical power, and modern passenger cars (or historic ones that have been modernized for current operation) use head end power for lights, heat, A/C, etc.

Sheldon

 

    

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Posted by NWP SWP on Saturday, January 21, 2017 9:34 PM

So true-to-prototype MU'ing is not logical but it was possible if the concept was developed further? Of course designs would have had to been changed to create the provisions for MU'ing.

Steve

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Posted by ATLANTIC CENTRAL on Saturday, January 21, 2017 9:29 PM

cascadenorthernrr

Ok thanks! Could a B-Unit be modified to have a control station installed?

 

Most B units did have basic controls that allowed the unit to be moved around the engine terminal seperately. But they are operated by a person standing in a small cramped space, often leaning out the door or looking out a porthole window.

Some of these controls had limited speeds, and most only had brake controls for the engine brake, not the train brake. They cannot control additonal units or operate a "train" in most cases.

So here is the next lession, railroad locos have two sets of brake controls, one controls just the air brakes of the loco, the other controls the air brakes on the whole train, another in the long list of complications in trying to MU steam with diesel.

Sheldon 

    

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Posted by NWP SWP on Saturday, January 21, 2017 9:15 PM

Ok thanks! Could a B-Unit be modified to have a control station installed?

Steve

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Posted by ATLANTIC CENTRAL on Saturday, January 21, 2017 9:12 PM

cascadenorthernrr

I see, could another engineer fit in the cab?

 

That is the point. Have you ever been in the cab of a steam locomotive? The short answer is in most cases no, there is no room. There is barely room for the engineer, fireman and maybe a cramped little seat for a headend brakemen - before you try to add all this extra control equipment and a second engineer.

I strongly suggest you find a museum or two to visit where you can actually sit in a steam loco cab. There are lots of such opportunities around, and historic diesel cabs you can climb in as well.

Sheldon 

    

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Posted by NWP SWP on Saturday, January 21, 2017 9:05 PM

I see, could another engineer fit in the cab?

Steve

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Posted by ATLANTIC CENTRAL on Saturday, January 21, 2017 9:03 PM

cascadenorthernrr

Ok then, from an experts point of view what would need to be added to the steamers cab to accomodate diesel MU'ing?

 

All the controls found in the diesel, and this is a BIG space/location problem for the already crowded steam loco cab. Not that it can't be done or has not been done, but it's not easy.

And from a safety standpoint, it is likely better that this second set of controls come with its own engineer, as a steam engineer already has his hands full a lot of the time. You saw the steam locos controls above, now add this to the mix:

http://www.cl.ais.net/~dbehr/463%20Control%20Stand1.JPG

No railroad locomotive is a 63 Dodge with a pushbutton automatic......

Sheldon

    

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Posted by NWP SWP on Saturday, January 21, 2017 8:50 PM

Ok then, from an experts point of view what would need to be added to the steamers cab to accomodate diesel MU'ing?

Steve

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Posted by ATLANTIC CENTRAL on Saturday, January 21, 2017 8:35 PM

cascadenorthernrr

Yes that is understood, what I meant is that the diesel would need a independent and dedicated throttle.

 

yes

    

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Posted by NWP SWP on Saturday, January 21, 2017 8:34 PM

Yes that is understood, what I meant is that the diesel would need a independent and dedicated throttle.

Steve

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Posted by ATLANTIC CENTRAL on Saturday, January 21, 2017 8:32 PM

cascadenorthernrr

So two throttles are absolutely necessary then.

 

Yes, again, understand that to operate a steam loco, you must do more than "move the throttle", you must move several "levers" and valves at the same time, much like letting out a clutch while applying the gas........

Then you make small adjustments to those settings based on how it feels and sounds.......we have not built that computer yet, only God has that formula....the human brain.

Sheldon

 

    

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Posted by NWP SWP on Saturday, January 21, 2017 8:10 PM

So two throttles are absolutely necessary then.

Steve

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Posted by ATLANTIC CENTRAL on Saturday, January 21, 2017 8:05 PM

cascadenorthernrr

Yes of course but could a throttle have been developed that operated the mechanical system and a electric system simultaneously so the engineer only has to operate one?

 

Not likely, even today. A steam locomotive requires a great deal of "feel" to operate, much like driving an old tractor/trailer with a stick shift.

The engineer must operate/balance a number of different "inputs" at the same time, there is no fixed relationship between the throttle, johnson bar, and steam cocks, and those are just the major items to control to make it move.....

In the "old days" when steam was double headed, the engineer in the second loco just controled his loco by "feel". When diesels came along and were double headed with steam, same rules applied, it was done by feel.

Today, modern diesels are controlled by fancy engine/traction computers, making the engineers job "different". But even early diesels required a "feel" for the machine and a good understanding of how it worked, and what it could and could not tollerate.

In the old days, double heading relied on experiance, being able to understand what the other engineer was doing by feel and by observing the brake pressure gauge.

Building some sort of system to translate the mechanial actions of a steam engineer into the correct information for a diesel loco would present untold challenges. Not the least of which would be accurately turning the mechanical movements of the steam throttle and Johnson bar into electrical information that could then be processed for the diesel control.

These factors are not constant on a steam loco. Move the throttle this much right now, with 300 psi, and get one result, move it the same amount 10 minutes later with 280 psi, get a different result - all of those results affected by the "cutoff" or position of the Johnson bar.

And these are just the raw basics.......I think you need a couple cab rides to understand how this stuff works.....

Sheldon 

    

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Posted by NWP SWP on Saturday, January 21, 2017 7:42 PM

Yes of course but could a throttle have been developed that operated the mechanical system and a electric system simultaneously so the engineer only has to operate one?

Steve

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Posted by 1019x on Saturday, January 21, 2017 7:39 PM

It has the be a separate throttle. You are talking apples and oranges with steam and diesel. A steam locomotive throttle is strictly mechanical. The engineer moves the throttle lever and it opens up a valve that allows steam to flow to the cylinders. Diesel engine controls are electric. The steam locomotives used today in excursions have been modified with a controller that has a electrical connection through an MU cable to the diesel helper.

cascadenorthernrr

Assuming that union work agreements and regulations were allowing and other problems were solved could: (theroetically speaking)

A: Diesels be MU'ed with a steam loco with a separate throttle in the steam loco's cab?

B: Diesels be MU'ed with a steam loco with a single consolidated throttle in the steam locos cab?

(This of course applies to a GS-4/PB lashup)

 

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Posted by NWP SWP on Saturday, January 21, 2017 7:16 PM

Assuming that union work agreements and regulations were allowing and other problems were solved could: (theroetically speaking)

A: Diesels be MU'ed with a steam loco with a separate throttle in the steam loco's cab?

B: Diesels be MU'ed with a steam loco with a single consolidated throttle in the steam locos cab?

(This of course applies to a GS-4/PB lashup)

Steve

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Posted by 1019x on Saturday, January 21, 2017 6:35 PM

Posted below is from the FRA 2012 Compliance Manual for Motive Power and Equipment Inspectors. You will note that speed indicators did not become mandatory per the FRA until December 31, 1980 and they are still not mandatory for a locomotive that will be operated at 20 MPR or less. And I remember when that rule went into effect.

§ 229.117 Speed indicators.
(a) After December 31, 1980, each locomotive used as a controlling locomotive at speeds
in excess of 20 miles per hour shall be equipped with a speed indicator which is --
 (1) Accurate within ±3 miles per hour of actual speed at speeds of 10 to 30 miles
per hour and accurate within ±5 miles per hour at speeds above 30 miles per hour; and
(2) Clearly readable from the engineer’s normal position under all light conditions.
(b) Each speed indicator required shall be tested as soon as possible after departure by
means of speed test sections or equivalent procedures.

 

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Posted by ATLANTIC CENTRAL on Saturday, January 21, 2017 5:55 PM

And I knew that, guess I should have looked closer.....

Yes, many "modern" steam locos had speed indicating equipment of one type or another, but as several of has have commented, most did not. In all the museum locos I have been in the cabs of (likely a hundred or so), I can only recall one or two with speedometers or speed recorders.

It should also be noted that while the Valve Pilot did indicate loco speed, its primary function was to indicate to the engineer the correct cutoff setting for a specific speed. Design, installation and setup of the Valve pilot was rather complex, requiring a custom ground cam to provide the speed and valve cutoff information to the engineer, and reserved mainly for the biggest and best at the end of steam.

Sheldon

    

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Posted by gmpullman on Saturday, January 21, 2017 4:40 PM

ATLANTIC CENTRAL
Lot of gauges - no speedometer:

Actually, Sheldon, there is a speedometer in the photo you posted. The Loco-Valve-Pilot includes a speed indicator, shown next to the throttle.

Here's another Valve-Pilot equipped backhead.

and a close-up of the Valve-Pilot control gauge:

I am of the opinion that the majority of steam locomotives did NOT have a speed indicating device, Barco speed recorder, Westinghouse made them, too. They were expensive to install and maintain and the heat and pounding of a steam locomotive over the road probably took their toll, too.

However, many of the "modern power" main line locomotives were Valve Pilot equipped or had a speed a recorder with a paper recording tape. I believe all the NYC Hudsons, Mohawks and Niagaras had them.

Regards, Ed

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Posted by Anonymous on Saturday, January 21, 2017 4:03 PM

PA : 10' 6",  EMD F7 10' 8". 

The PA looks wider because it is slighly shorter (14' 8") vs 15ft.  Plus the long "nose".

 That having been said, you would likely find a GS4 rescuing a Alco PA-PB set due to engine failure.  The ALCO 244 was unreliable engine, and contributed to the company's demise.

Here's a useful website about your locomotive:  http://www.steamlocomotive.com/northern/?page=sp

Just out of curiosity, why would you need to make it into a tunnel motor?  The GS class was/are oil burners, so there arent really cinder concerns, even if there were then there's this:

https://www.youtube.com/watch?v=hfBK301BVhA

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