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Multiple Steam Locos Before Computers

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Multiple Steam Locos Before Computers
Posted by RichLikesTrains26 on Wednesday, May 3, 2023 7:43 AM

I'm curious how multiple steam locomotives were able to work either in tandem at the head end of a train, or both at the head end and as pushers, without computer control that modern locos have today. Was this an "art" simply done by experienced engineers? Or was there some sort of ruidmentary system pre-dating computer control?

How did air brakes work if there were multiple locos on a train? Was just the head-end loco responsible for air brake pressure and control?

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Posted by Overmod on Wednesday, May 3, 2023 9:38 AM

Let me do the last one first.  The head end of a full doubleheaded consist had the brakes, and ideally the ATC shoe or receiver if there was one.  That leaves the automatic brake in the control of the engineer with the 'best view'.  Each locomotive had its own independent, and there was no way to actuate one locomotive's independent brake from another.  The trailing engine, though, retained the ability to set brakepipe pressure or trigger an emergency application in emergencies, just as a conductor on a passenger train or the 'rear-end crew' on a caboose could do, and there were rules concerning the duty to "take the safe course" and pull the air if you thought the engineer was incapacitated or had forgotten something...

The train-handling necessary to divide tractive effort equally between two (or more) locomotives has to be learned.  But note that it is immaterial to how the locomotives pull on the train: whether one locomotive develops more power than the other, both continue to pull on the train.  You'll see evidence of this in many, many doubleheaded shots where one locomotive has a clear stack and the other is erupting smoke or steam...

The way engine crews communicated when necessary was via whistle signals -- for example one blast meant 'stop', two meant 'proceed forward', and three 'back up'.  (I actually heard someone running a Gradall excavator communicating with the others on the crew by blowing the truck horn to indicate how he was about to move...)  You may have already noted that a passenger signal line can use the same convention -- the conductor will sound 'peep peep' in the engine cab, that engineer will respond with two crisp blasts on his whistle in acknowledgement, and that will signal any double or helper power that it's time to be proceeding.

Where the 'other' locomotive(s) are helpers or snappers, I suspect most of the communication was done by reading the progress of the train, and subject to individual railroads' rules.  This is particularly true for systems that cut the helping locomotives off 'on the fly'.

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Posted by timz on Wednesday, May 3, 2023 11:18 AM

RichLikesTrains26
was there some sort of rudimentary system

Nope, no system. And no radio for the engineer at the front of the train to tell the guy at the rear to start pushing. On freights, nothing but changes in brake-line pressure, and maybe whistle signals.

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Posted by BaltACD on Wednesday, May 3, 2023 4:02 PM

timz
  
RichLikesTrains26
was there some sort of rudimentary system 

Nope, no system. And no radio for the engineer at the front of the train to tell the guy at the rear to start pushing. On freights, nothing but changes in brake-line pressure, and maybe whistle signals. 

One thing to remember about those days, as compared to today.  The overall sound levels in the settings where railroads operated were much quieter than things are today.  When steam was the primary motive power on the railroads, internal combustion cars and trucks were nowhere near as ubiquitous as they are today.  In a 'quiet world' the sound of a steam whistle would have the power to travel a mile or more and still be heard accurately.  Whistle signals between head end and helper crew was the communicaion standard of the day.

Next, remember, both controlling Engineer and helper Engineer(s) are qualified on the territory they are operating - they know the geographical 'tricks' the terrain will be throwing at them as the progress across the territory and how to respond to those 'tricks'.

I have no idea where anyone lives, with that being said, listen to the background 'noise' outside your residence at 3 PM.  Now go outside at 3 AM and see how much less the background 'noise' is.

The second thing to consider is that in steam days the 5000 foot train was a relative rarity - they existed, but they were not the rule - 2500 - 4000 foot trains were the norm.

When I broke in being employed on the B&O in Southern Indiana/Illinois in 1965.  Locomotives and cabooses were not radio equipped.  Crews, however, took it upon themselves to purchase CB radios and make temporary installations of them on the locomotives and cabooses they were using to facilitate end to end communications.

Never too old to have a happy childhood!

              

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Posted by mvlandsw on Wednesday, May 3, 2023 4:08 PM

Diesel helpers worked the same way and still do, unless there is some kind of DPU system in use. I would always try to have an extra MU cable when working helpers to plug in when double heading a train. This avoided having to depend on the train's engineer to match how I was handling the train.

Rear end helpers operated mostly by knowledge of the route, the feel of how the train was handling, and watching the air gages.

When radios became common communication became much easier.

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Posted by timz on Wednesday, May 3, 2023 8:06 PM

Speaking of ambient noise -- I was lying in bed just after midnight, with the window open 3 inches. I heard an airliner pass overhead -- looking it up on flightradar24.com, it turned out to be an A350 at 36,000 feet enroute ONT to TPE. My hearing isn't awful, but it's worse than average.

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Posted by BaltACD on Wednesday, May 3, 2023 11:56 PM

timz
Speaking of ambient noise -- I was lying in bed just after midnight, with the window open 3 inches. I heard an airliner pass overhead -- looking it up on flightradar24.com, it turned out to be an A350 at 36,000 feet enroute ONT to TPE. My hearing isn't awful, but it's worse than average.

During the day - you never would have heard it - even if you were listening for it.

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Posted by jeffhergert on Thursday, May 4, 2023 12:43 AM

Helpers, steam or diesel, that are cut into the train's brake pipe would have their automatic brake valve cut out. Only the lead engine would control the train brake. Individual engineers would still control their engine's independent brake. Helper engineers would watch brake pipe pressure and bail off as needed.

With the automatic cut out on the helpers, the only train brake application they could make is emergency.

Something that occasionally happens when a seat on a trailing unit isn't locked in place.  It can swing around and knock the automatic brake handle into emergency. 

Jeff 

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Posted by CSSHEGEWISCH on Thursday, May 4, 2023 10:02 AM

timz

Speaking of ambient noise -- I was lying in bed just after midnight, with the window open 3 inches. I heard an airliner pass overhead -- looking it up on flightradar24.com, it turned out to be an A350 at 36,000 feet enroute ONT to TPE. My hearing isn't awful, but it's worse than average.

 
I live about a mile south of Clearing's bi-directional hump and routinely hear the squealing of the retarders both day and night but they are definitely easier to hear later in the evening.
The daily commute is part of everyday life but I get two rides a day out of it. Paul
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Posted by timz on Thursday, May 4, 2023 11:18 AM

jeffhergert
that occasionally happens when a seat on a trailing unit isn't locked in place.  It can swing around and knock the automatic brake handle into emergency.

That occasionally happens nowadays? Someone is supposed to latch the seats on each head-end unit, and each DPU? Any of them can cause a UDE? If that does happen, is it easy to figure out what caused the UDE?

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Posted by jeffhergert on Thursday, May 4, 2023 12:07 PM

timz

 

 
jeffhergert
that occasionally happens when a seat on a trailing unit isn't locked in place.  It can swing around and knock the automatic brake handle into emergency.

 

That occasionally happens nowadays? Someone is supposed to latch the seats on each head-end unit, and each DPU? Any of them can cause a UDE? If that does happen, is it easy to figure out what caused the UDE?

 

 

Yes it still happens.  The modern brake handles can be pinned in the handle off position.  If there isn't a pin, then the seat should be locked.

Unless it's known on the head end that seats and/or brake handles are locked, that's the first place to check.  If there's DPs, it's good to check them when the conductor is walking back.  Especially if the conductor has walked the train and not found a brake pipe separation or failure that won't let air be restored through the train.

Jeff

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Posted by BaltACD on Thursday, May 4, 2023 12:47 PM

jeffhergert
Helpers, steam or diesel, that are cut into the train's brake pipe would have their automatic brake valve cut out. Only the lead engine would control the train brake. Individual engineers would still control their engine's independent brake. Helper engineers would watch brake pipe pressure and bail off as needed.

With the automatic cut out on the helpers, the only train brake application they could make is emergency.

Something that occasionally happens when a seat on a trailing unit isn't locked in place.  It can swing around and knock the automatic brake handle into emergency. 

Jeff 

On B&O's electrified helper zone from Bailey to Waverly through the Howard Street Tunnel I don't think the electric engines coupled air into the train.  The electric engines would couple to the head end of Eastward trains and haul them through the lower level of Camden Station, Howard Street Tunnel, Mt. Royal Station and cut off on the fly approaching Waverly to enter the helper pocket in the Waverly interlocking plant and let the helped train pass by under that trains own power.

When the electric helpers were connected the road engines would not work their steam power until after clearing the trainshed of Mt. Royal station.  The entire helper district was less than 4 miles climb nominal one percent grade.

The electric helpers were eliminated in the early 1950's when all traffic, passenger and freight, on the Baltimore Division was dieselized.

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Posted by Erik_Mag on Thursday, May 4, 2023 10:17 PM

Speaking of electric helpers...

On long "dead" freights, the Milwaukee would have a set of box-cabs on the front and another set somewhat after the middle of the train. A lot of the coordination was done by whistle (horn?), but the crews also had the voltmeter measuring the catenary potential. Changes in the line voltage gave a fair amount of info on what the other crew was doing.

"Dead" freights were what the Milwaukee called drag freights.

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