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prototype train speeds

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prototype train speeds
Posted by queenidog on Tuesday, July 3, 2012 12:22 PM

Is there a list of prototype train speeds somewhere?  I just recently determined the speed of my 6 HO locos which consisted of a couple switchers and a couple main-line diesels.  I want to dial in the proper speed curves in DCC so that the speeds are realistic.  It wouldn't do to have the mainline max speed slower than a switcher for example.  I Googled the question and only found a max speed of a GP35 (65mph).  

 

I have a GP35, GP70, S4, EMD F9, EMD SD-45 and an SD-60

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Posted by fwright on Tuesday, July 3, 2012 1:12 PM

queenidog

Is there a list of prototype train speeds somewhere?  I just recently determined the speed of my 6 HO locos which consisted of a couple switchers and a couple main-line diesels.  I want to dial in the proper speed curves in DCC so that the speeds are realistic.  It wouldn't do to have the mainline max speed slower than a switcher for example.  I Googled the question and only found a max speed of a GP35 (65mph).  

What do you define as realistic?  Except for the S4 (a switcher), I would guess the max speeds with normal factory gearing to be in the 60-75 MPH area. 

But are you ever going to operate at prototypical max speed on your layout?  At 60 scale MPH in HO, your train is going to travel 1ft per second.  A loop of track on a 4x8 with 22" radius curves is just under 20ft long.  So it takes 20 seconds at 60MPH for each circuit of the layout.

From my observations of driving I-80 through Nevada, and I-25 between Denver and Pueblo, I see trains on open stretches of track typically running around 45-50 MPH, and much, much slower in congested areas.  I rarely see more than 60, based on how fast I am passing the train.  Most of our layouts consist of track that would be regulated at quite slow speeds by the prototype.  And slower operating speeds don't make our model main lines seem as short as they are.  Since I model an era before the advent of regular high speed freight, my layout speeds are even slower.  I find 30MPH to be a good main line speed, with slower on grades and in congested areas. 

Switching is generally at 5MPH on the prototype.  Switching on the layout at that speed is acceptable as long as train lengths are quite short.  Switching (or even drag freight) at 5MPH (12 seconds per foot in HO) with a 30 car train (16ft long) is just too slow for many-to-most operators.

To recap, I find train length and length of layout tracks to have as much impact on layout operating speed as the prototype practice or maximum speed.

my thoughts, your choices

Fred W

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Posted by cv_acr on Tuesday, July 3, 2012 1:23 PM

Well, there's a max speed that a particular engine is geared for/capable of, and then there's the speed limits required in a particular area or by track conditions at a particular point. The GP35 might be rated for 65MPH, but the line it's operating on might have a speed limit of 40MPH (or more, or less). (Just like your car might be capable of 100MPH, but going that fast is not recommended or legal.) There may also be separate speed limits for freight or passenger trains.

Prototype speed limits for a particular line for freight and passenger trains will be spelled out in the employee's operating timetable, including locations of permanent speed restrictions for curves, bridges, etc.

At junctions and interlockings, switches will have a certain design speed that they are rated for. These speeds are normally set out as:

RESTRICTED SPEED - A speed that will permit stopping within one half the range of vision. Where ABS rules, interlocking rules or signal indications require movement at restricted speed, such movement must be made at a speed that will permit stopping within one-half the range of vision, also prepared to stop short of switch not properly lined, and to be on the lookout for broken rail, and in no case exceeding SLOW speed.
SLOW SPEED - A speed not exceeding fifteen miles per hour.
MEDIUM SPEED - A speed not exceeding thirty miles per hour.
LIMITED SPEED - A speed not exceeding forty five miles per hour.

(above taken from the 1962 Uniform Code of Operating Rules. This was the rulebook used for several decades in Canada, and very similar to most US rulebooks.)

Operating on a non-main track is required to move at Restricted Speed. Slow, Medium or Limited speeds are dictated speeds for taking a diverging route through crossovers or switches at an interlocking. Signal systems that use "Speed Signalling" (the signal indications explicitly indicate the max speed for the route lined) will explicitly indicate the speed by the combination of colours displayed on the signal. "Route Signalling" will only indicate straight or diverging, and the crew must know the design speed of the switches through their familiarity with the territory.

All Canadian systems use Speed Signalling, American railways are split maybe half and half between versions of Route Signalling or Speed Signalling.

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Posted by wjstix on Tuesday, July 3, 2012 3:06 PM

Another factor is that our model curves are very sharp...even on "broad" curves (30" radius in HO) a real train would be restricted to about 20 MPH.

Also, getting your engines speedmatched so they all run well together may be better than setting each individual engine to it's own maximum speed.

Stix
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Posted by tomikawaTT on Tuesday, July 3, 2012 6:10 PM

Prototype speeds come in several flavors:

  1. Maximum locomotive speed - locomotive type specific.  Above this speed a steam locomotive's dynamic augment will start to destroy the track, and itself.  Traction motors will come apart, with unhappy results.
  2. Track speed - set by FRA definition, with level of maintenance determining speed.  Ranges from 10mph to as fast as you dare, depending on classification.
  3. Speed according to signal indication, which has been covered above.
  4. Speed set by specific physical conditions.  The track may be maintained for 79 mph, but that one buttonhook at the turn in the river will be posted 15 mph in the employee timetable and on a sign at trackside.

Note that last item.  Failure to take a 15 mph curve at the appropriate speed led directly to N&W No 611 being the only surviving Class J 4-8-4.  Since it had been recently overhauled after that wreck, it was in the best condition when the management decided to set a J aside for preservation.  All of its sisters went to the scrap line.

On my own layout speed set by physical conditions is the governing factor.  The railroad follows a river deep in a steep-sided canyon.  The locating engineer used a snake for a straightedge, and equipment which could run tangent track at 70 or 90 never exceeds 40kph on the visible parts of the JNR.  Any d'raiba foolhardy enough to exceed the 25kph speed limit on the TTT would be living out a death wish - that locating engineer found the route by following a mountain goat...

Chuck (Modeling Central Japan in September, 1964)

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Posted by doctorwayne on Wednesday, July 4, 2012 4:01 AM

I've added speed limit signs to most of the layout:



Eventually, I'll add "speed traps":  measured distances denoted by "START" and "END" signs through which crews can time their trains, then consult a chart on the layout fascia showing their speed.  This should give operators a better sense of what a given speed looks like. 
The highest posted speed is 45mph, mostly on uphill runs where a train of any length would be unlikely to be capable of attaining it. Smile, Wink & Grin


Wayne

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Posted by BRAKIE on Wednesday, July 4, 2012 11:46 AM

Average train speeds isn't all that fast according to the weekly performance charts given by the railroads...

As examples.

These are NS speeds:

Intermodal:30.0 mph.

Manifest: 23.9 mph.

Multilevel :24.9 mph

Coal Unit :18.2 mph

Grain Unit :18.8 mph

For other roads:

http://www.railroadpm.org/Performance%20Reports/NS.aspx

Look in the upper left hand corner for the other roads.

Larry

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Posted by dehusman on Thursday, July 5, 2012 7:36 AM

Normally a freight diesel has 65-70 mph top speed, an engine with out swing motion trucks (AAR type B switcher truck) is limited to about 45 mph and engine geared for high speed service (pasenger) are geared for 80-100 mph.

The average speeds for freight service Brakie quoted are the average speed over the entire route of the train and do not reflect how fast the train may be traveling at any given point.

If a train runs 240 miles non-stop in 4 hours its running 60 mph.

A train runs 80 miles at 60 mph, then takes 30 minutes to make a pickup, runs 40 miles at 60 mph, then takes 1 hour to make a pick up and set out, then runs 60 miles at 60 mph, takes 30 min to make a set out and runs the last 60 miles at 60 mph.  At any point the train is running 60 mph.  But the average train speed was 4 hours running and 2 hours working for a total of 6 hours, so the average speed was 40 mph. 

Throw in train meets, crew changes, fueling stops, normal track speed restrictions, etc and its easy to get the average train speed over a long distance down to the 20-30 mph range, even though at any given point the moving train might pass you at 40-50 mph.

Dave H. Painted side goes up. My website : wnbranch.com

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Posted by rrinker on Tuesday, July 10, 2012 8:12 AM

How fast they CAN go is pretty basic - it's set by the RPM of the traction motor at full voltage combined witht he gear ratio and wheel diameter.

How fast they actually go - that's the rules, signal indications if speed signalling is used, track conditions, train weight, grade, and safety considerations.

Probably the most annoying part of Unstoppable - how they exaggerated the train speeds, mainly for the non-railroad audience. Most people wouldn;t get that a train running even 30mph with no brake lines connected is, indeed, pretty much unstoppable. 30mph? That's slow. Heck, I go 70 in my car.. Yes, and your car weighs less than one truck on the locomotive. So they exaggerated it all to allow peopel to realte, I supposed. Unless there were no curves at all except for that curved elevated track at the ned, it's doubtful the train would have stayed ont he tracks at the speeds they claimed ot be reaching.  And in a light locomotive trying to run those speeds, there would have been no need for 'shaky cam' effects in the cab with Chris Pine and Denzel.

In the end - it's all about physics - mainly momentum and the part about objects moving in a straight line. It's amazing really, how all he forces of a heavy train are contained by the relatively light-looking rails.

                           --Randy

 


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Posted by capt.monkey on Wednesday, July 11, 2012 8:27 PM

If you want to figure out speeds like the prototype, you need to determine what a mile is on your layout. Then you need to time the loco between mile 0 and mile 1.

The table below is taken from page one of a timetable in my rulebook.

SPEED TABLE
Time per mile           MPH
36 sec                       100.0
38 sec                        95.0
40 sec                        90.0
42 sec                        85.7
45 sec                        80.0 
48 sec                        75.0
51 sec                        70.6
55 sec                        65.5
1 min 5 sec               55.4
1 min 12 sec             50.0
1 min 20 sec            45.0
1 min 30 sec            40.0
1 min 43 sec            35.0
2 min                         30.0 
2 min 25 sec            25.0
3 min                         20
4 min                         15
6 min                          10
12 min                        5 
15 min                       4
20 min                         3
30 min                       2
1 hour                         1

 

Edit: As for the actual speeds they travel, it varies based on the subdivision. If you send me a PM, I can email you a couple of current time tables in pdf format

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Posted by narrow gauge nuclear on Tuesday, July 17, 2012 2:48 PM

The narrow gauge, D&RGW and RGS were all very low speed railroads and the all steam remains of the D&RGW is still a slow roll affair to this day.  It was certainly far slower in the early 1900's where almost all the branch lines were 15mph max speed and, at many points, the max allowable speed was 5 mph.  Mainline speeds never exceeded 35 mph on even long straight track sections!  After the 1960's when passenger service returned to the tourist D&S and the C&T, still all steam, the track was upgraded to 70 lb rail and some rare stretches, especially on the C&T over open prairie can see 40mph.

Most of the lower early speeds were not due to visibility issues, but track, grade and terrain issues.  Slightly heavier engines purchased in 1903 and the 1920's had to run on 40lb rail laid in the 1880's in many instances. Track upgrades and weak bridges were replaced only very slowly such that even today double header steam trains can't cross, some trestles with their trains, but have to break up and cross singley.  As late as the 1950's none of the 1900s motive power could operate on several branches due to bridge weight limits.  Only the ancient, but still in service, 1890's C class, tiny consolidations could work those branches, mostly at 15mph.

Prototype speeds on model narrow gauge roads require real crawling capability.  Fortunately, proper gearing and neodymium can motors by modern motive power makers allows the best engines to pull their protoypical trains of about 5-15 cars over modeled prototypical grades at prototypical speeds.

Most of the narrow gaugers on you tube seem to observe prototypical speeds with only a few exceptions.

Richard

Richard

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Posted by mlehman on Wednesday, July 18, 2012 8:35 AM

Lots of good advice above already. My contribution is to think about how most layouts use selective compression. Our towns and yards are smaller, because there's not room for everything. Even more compressed is the trackage between towns and other locations. Long stretches of single track running through the countryside are nice, but represent a very small percentage of what's depicted on most layouts.

All that is just another reason why slow is the word when it comes to layout speeds. You're operating mostly on track that would see restricted speeds in real life.

Mike Lehman

Urbana, IL

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Posted by kansaspacific1 on Wednesday, July 18, 2012 9:43 AM

Another issue mentioned in a couple of the above posts is speed limits.

If you are modeling a specific railroad, get an employee timetable for the period you model, and most likely it will contain a table of speed limits for various types of locomotive and train.  Eg: Streamlined passenger, diesel heavyweight passenger, steam passenger, steam freight, helpers, work equipment, etc.  Also for specific areas of the line, yards, cities, small towns, open country, through various turnouts, at various junctions, etc.

I think you'll find the range of speeds interesting and probably slower than you might expect.

Just another facet of faithfully modeling the prototype.

Chuck

 

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Posted by sturg on Friday, July 20, 2012 1:54 PM

I'm building an early 1900's logging layout with mostly geared steam locomotives (Shays, Heislers, Climaxes, Vulcan Duplex, etc.).   I operate them at very low speeds, typically 15 to 20 scale MPH and really enjoy the slower operating speeds.   As a bonus, it makes my 13' x 16' "U" shaped layout seem larger as well.   Some of the videos of professional high end layouts (of any vintage) show trains being operated at what seems to be excessive speed, even in switching, etc.    To me, excessive speed makes everything seem more "toy like". 

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Posted by wjstix on Tuesday, July 24, 2012 8:27 AM

Actually for geared engines, 15-20 MPH might be a bit on the fast side. Wink

One of the reasons rod engines were more common on logging railroads here in Minnesota was the relatively long trips (20-40 miles) they had to make would take forever with a geared engine. I have a little two-truck Spectrum Climax engine that I rarely run at 10 MPH or more. It seems to cruise along nicely around 6-8 MPH.

Stix
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Posted by BRAKIE on Wednesday, July 25, 2012 4:49 PM

Dave:

The average speeds for freight service Brakie quoted are the average speed over the entire route of the train and do not reflect how fast the train may be traveling at any given point.

-----------------------------------

Dave,Those are the speeds the railroads uses for performance not the track spped which in real railroading doesn't mean very much since there is always speed restrictions through curves,over switches,slow orders,slower speeds for certain type of freight cars in the the train consist,grades,speed restrictions through cities,towns,over bridges and so on.

So,the speeds they show are the correct "real time" train speeds..

Your 60 mph would be more of a short sprint then average speed.

Larry

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Posted by dehusman on Thursday, July 26, 2012 1:30 PM

BRAKIE

Dave,Those are the speeds the railroads uses for performance not the track spped

I know.  I have over 30 years experience in prototype railroads and use those speeds in meaures and analysis all the time.  As you pointed out, they are an aggregate speed, NOT the track speed.  They include any stops the train makes along the way.

which in real railroading doesn't mean very much since there is always speed restrictions through curves,over switches,slow orders,slower speeds for certain type of freight cars in the the train consist,grades,speed restrictions through cities,towns,over bridges and so on. 

It might no on your railroad but track speed makes a difference on mine.  8-)

Really the biggest driver on lowering train speeds is stops  the train makes.  Set outs, pick ups, fueling, inspections, train meets, maintenance gangs.  They kill the velocity of the train.  Yes, slowing a train down to 35 mph for a couple miles delays the train, but stopping it for 15 minutes hurts the train even more.

  So,the speeds they show are the correct "real time" train speeds..

They are a real speed, but not a real time speed.  The performance speeds are the aggregate, average speed over the entire run.  If you look at the train speed statistics reported to the AAR by the class one carriers, the BNSF and the UP lately have been in the 27 mph range and the CSXT and NS are in the 23 mph range.  Those speeds are the system aggregates of the speeds you are discussing.  Does that mean that if you stood by the tracks the trains would be going by you barely over restricted speed?  No, of course not, they will in most cases be doing 40-50-60  mph for miles.

Your 60 mph would be more of a short sprint then average speed.

And that's my point, your speed is an average.  A train's trip is made of "short sprints" separated by stops.  The stops are averaged into the speed for the train performance speed.   The average speed will not be the observed speed.

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Posted by cv_acr on Monday, July 30, 2012 2:02 PM

And the original question was "how fast can [a particular locomotive or train] go?" (i.e. peak speed) not what's the average speed performance over the network.

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Posted by dehusman on Monday, July 30, 2012 2:20 PM

And the typical answers were freight diesels 65-70 mph, pasenger units 80-100 mph, switchers without road trucks 45 mph.

Steam engines were all over the place (very, very rough rule of thumb, driver diameter in inches = max speed in MPH) .

Cars are all over the place.

Heavily era dependent.  My 1876 P&R rulebook restricts loaded coal trains to 6 mph , the 1894 editin limits loaded coal trains to 15 mph, modern railroads may restrict them to 50 mph.

Track without block signals in the US,  49 mph freight, 59 mph passenger.

Timetables and special instructions may have 2-6 pages of different speed restrictions for equipment and timetables or special instructions for each subdivisions have lists of permanent speed restrictions for the track.

Dave H. Painted side goes up. My website : wnbranch.com

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Posted by BRAKIE on Monday, July 30, 2012 2:21 PM

cv_acr

And the original question was "how fast can [a particular locomotive or train] go?" (i.e. peak speed) not what's the average speed performance over the network.

The average speed is the top speed.

There's no eagle eye with eye on the rail with hand on wide open throttle.That's fantasy.

I just seen the NKP 765 at speed-a whopping 39 mph according to her gps.

The intermodel in front of the 765 was running about the same speed.

We know 765 was a speedster  but,that to was fantasy in real operation.

So,why worry over top speed?

Larry

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Posted by jeffhergert on Tuesday, July 31, 2012 9:08 AM

I've had trains were I could run at the maximum allowed speed for 50 or 60 miles.  Other places the train is at a crawl going over hills.  Average speed isn't the top, nor bottom speed.

I had an Amtrak detour once where we went 197 miles in 3 3/4 hours.  That averages to about 52 mph.  Most of the trip was at the maximum speed allowed, 70mph.  There were a few permanent slows, two 30 mph crossovers, and the last 10 miles was done at 15mph under (automatic) train control, the exCNW cab signal system.  All that skews the average down.  Top speed is not the average speed.

 

Jeff 

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Posted by BRAKIE on Tuesday, July 31, 2012 10:22 AM

jeffhergert

I've had trains were I could run at the maximum allowed speed for 50 or 60 miles.  Other places the train is at a crawl going over hills.  Average speed isn't the top, nor bottom speed.

I had an Amtrak detour once where we went 197 miles in 3 3/4 hours.  That averages to about 52 mph.  Most of the trip was at the maximum speed allowed, 70mph.  There were a few permanent slows, two 30 mph crossovers, and the last 10 miles was done at 15mph under (automatic) train control, the exCNW cab signal system.  All that skews the average down.  Top speed is not the average speed.

 

Jeff 

In my 9 1/2 years old railroading the top speed was never near the maximum speed allowed due to slow orders,speed restrictions and so forth and at 24 mph average seems right on to me.

If and when we hit track speed it was a short sprint before we had to start applying the slow down.

The average trip between Queensgate and Russell was 8-10 hours.We even "outlawed" once at Garrison,Ky..

Larry

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Posted by dehusman on Tuesday, July 31, 2012 11:45 AM

BRAKIE
The average speed is the top speed.

This appears to be my stop.

Dave H. Painted side goes up. My website : wnbranch.com

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