 Joined: 05/07/2020(UTC) Posts: 326 Location: Mississippi, Vancleave
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During the steam era in the U.S. there would be double header, and even quadruple header trains. How in the world would the engineers of the locomotives syncronizethe engines so each engine would contribute equql power and not become a drag. Later on during diesel, the locomotives would syncronize so all power was being used. I've noticed in videos of double header steam that one engine would be putting out more black smoke indicating that loco was doing more work than the other.
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Joined: 16/02/2004(UTC)
Posts: 15,442
Location: DE-NW
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Originally Posted by: Mr. Ron  I've noticed in videos of double header steam that one engine would be putting out more black smoke indicating that loco was doing more work than the other. How does black smoke relate to work done by the loco? The more work a loco does, the more white steam should be coming out of the smoke stack. AFAIK the black smoke only indicates that the fire is not burning efficiently and that coal (or oil) is being wasted. In Germany AFAIK one loco would give a signal with the whistle and all locos would apply power. And AFAIK pushing locos are still not synchronized, so loco drivers still must apply power at the same time. But I think voice communication is used now instead of whistle signals. |
Regards Tom --- "In all of the gauges, we particularly emphasize a high level of quality, the best possible fidelity to the prototype, and absolute precision. You will see that in all of our products." (from Märklin New Items Brochure 2015, page 1) ROFLBTCUTS  |
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Joined: 23/04/2019(UTC)
Posts: 497
Location: Copenhagen, Denmark
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I googled double header steam locomotives. One answer: "Although mostly as long as both throttles are open and both engines are working okay, they should both be contributing drawbar thrust. These locomotives aren’t just rolling freely on the track, they are both attached to a train weighing thousands of tons, so even if the lead locomotive isn’t as powerful as the trailing one, it should still be helping the other one to pull. It doesn’t mean each is doing 50% of the work, but neither should be holding the other back either. That said, there certainly are stories of locomotives being assigned helpers that aren’t in proper working order, where the crew was certain the other was actually hurting more than helping, for example, a helper engine hooked onto the head, and the crew swearing that the drawbar was pushed tightly together the entire time, since even with the train attached, the other engine was pushing the helper ahead of it. But these are anecdotes."From: https://www.quora.com/In...ulling-one-of-the-other-There are several other search results worth looking into.
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 Joined: 23/07/2014(UTC) Posts: 8,464 Location: ENGLAND, Didcot
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I have quoted this story here before, where UK drivers thought that a helper loco at the back of a train wasn't 'helping', when they entered a tunnel would get the coal shovel nice and hot in the fire, then take it out and pee on it. The fumes would hang around in the tunnel, being drawn along by the train. It would certainly cause the helper loco to stoke up and try and get out of the tunnel sooner ... 
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 3 users liked this useful post by kiwiAlan
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 Joined: 26/07/2021(UTC) Posts: 635 Location: Sydney
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Blue Mountains Australia triple header steam and two diesels on the back. From about 1m 30s
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4 users liked this useful post by Toosmall
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Joined: 05/07/2020(UTC) Posts: 326 Location: Mississippi, Vancleave
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What is the reason for diesels at the end of the train? My guess is: to provide backup in case of engine failure or because the steam engine cannot refuel due to lack of refueling facilities such as coaling towers or water tanks.
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Joined: 26/07/2021(UTC) Posts: 635 Location: Sydney
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Through the Blue Mountains is a main line so it can't be blocked if avoidable. My guess it was probably a condition for operating the steam locos.
Coal & water in the area is not an issue, might need the help of the fire brigade to pump water from a tanker & a few wheelbarrows for the last few metres for coal.
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Joined: 23/07/2014(UTC) Posts: 8,464 Location: ENGLAND, Didcot
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Originally Posted by: Mr. Ron What is the reason for diesels at the end of the train? My guess is: to provide backup in case of engine failure or because the steam engine cannot refuel due to lack of refueling facilities such as coaling towers or water tanks. That is one possible reason, but another reason is that many steam locos cannot haul a 'normal' size train at modern mainline speeds. I had occasion to take a train trip from Charlottenburg, Berlin to Hannover and return to celebrate 21 years of the reunification of Germany. The organisers started off thinking maybe they would end up with a half dozen coaches comfortably full. They ended up with a maximum length 15 coach train fully booked and a second train the following day for the overflow. The steam loco they were using could not haul a 15 coach fully loaded train at mainline speeds, so a diesel loco was attached at the rear to ensure there was enough horsepower available to get up to speed so the train could be slotted into the normal timetables without holding up the other trains.
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Joined: 16/02/2004(UTC)
Posts: 15,442
Location: DE-NW
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Originally Posted by: Mr. Ron What is the reason for diesels at the end of the train? They are at the end to keep them out of sight. Often they are required to supply pressurized air to the train (e.g. automatic doors). Often they help to push the train, so the steam loco does not have to do all the work to prevent it from wear and damages. |
Regards Tom --- "In all of the gauges, we particularly emphasize a high level of quality, the best possible fidelity to the prototype, and absolute precision. You will see that in all of our products." (from Märklin New Items Brochure 2015, page 1) ROFLBTCUTS |
1 user liked this useful post by H0
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Joined: 05/07/2020(UTC) Posts: 326 Location: Mississippi, Vancleave
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Originally Posted by: H0 Originally Posted by: Mr. Ron What is the reason for diesels at the end of the train? They are at the end to keep them out of sight. Often they are required to supply pressurized air to the train (e.g. automatic doors). Often they help to push the train, so the steam loco does not have to do all the work to prevent it from wear and damages. I saw this 14 months ago when the "big boy" passed through. They had a diesel right behind the tender and I understand the reason was the availability of fuel during the 1000 mile tour and to reduce wear and tear.
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1 user liked this useful post by Mr. Ron
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Joined: 26/07/2021(UTC) Posts: 635 Location: Sydney
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Through the Blue Mountains is not that long. Main line speed is about the pace of a small, I have been on this route a few times on a modern train and it is painfully slow. Twice, Sydney to Orange return (254km one way) with about a couple of hours turn around, and said Sydney to Dubai (14 hours) is quicker! Some of the track radiuses are as little 240 metres. Used to be down to 160 metres until they "straighten" the worst of the track.
It probably only did Sydney to Lithgow (141 km one way) and returned.
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