What's a "measured mile"?

[mudchicken]

QUOTE: Originally posted by ValleyX

The other day, this fellow said he is an engineer. I'll bet his speedometer is always off.

Why would you expect that? Just because those 19 inch hi-rail wheels didn't come as original equipment on a 3/4 ton pickup?[:D][:D][:D]

[ValleyX]

The other day, this fellow said he is an engineer. I'll bet his speedometer is always off.

Rodney, we had test miles long before we had footcounters on engines.

Santa Fe, posts every 10,000 feet out of a terminal. What an aid that would have been. I've always been told that those Western roads did it right, all kinds of things to help the crews that I've never seen in my Eastern experiences.

[mudchicken]

(1) Out of any terminal, ATSF would set measured miles AND would also set posts every 1000 feet out to 10,000 feet. Every two years we would go out and chain-in the locations for the posts and mark them on the rail along with terminal limits, yard limits and switching limits. (amazing how far some of those posts would wander)
(1a) The measured miles were to check train speed with a watch versus the mechanical speedometer. There always was a concersion chart at the back of your timetable to make it easier. In the 1980's, it was common for road crews to call-in that the speedometer was off. (Which could be a combination of bad meter box, wheel slip, worn wheels and so on)
(1b) Crews would also check the length of the train versus what the car clerks and yardmasters had given them as insurance when going in the hole that they would not foul the main track or block crossings.
(2) The number of poles per mile could be anywhere between 30 to 55 dependent on the number of wires, cross-arms (gain spacing) and importance of the line. Timetables used to tell you how many per mile.
(3) Long and short miles. Have seen railroad miles as short as 800 feet and as long as 9900 feet after line changes. (and NO, you do not reposition the mileposts after every linechange....or you get the mess between Denver and Pueblo created by the BN operating people who were not too bright to begin with, 15 watters all....their MP 5 to MP 119 disappeared for good in 1937 and they didn't like ATSF's MP 619 to MP 733 running backwards to them)

Maybe our 5000 foot per mile guy worked for BN?


[banghead][banghead][banghead]

[Rodney Beck]

A measured mile is for the engineer to check the footage counter to see how far off it is to determine how long or short it is so i can judge if my rear clears in the sideing or crossover, also I do a speedometer against the clock to find out how accurate it is. Since when did a rail mile come out to 5,000 feet.

Rodney

[Anonymous]

Federal roads in many states have -- or had -- measured miles too. It was the exact same concept; check your odometer and/or speedometer, but the regular land statute mile of 5,280 was used.

[88gta350]

QUOTE: Originally posted by mackb4

A measured mile is the one mile distance of 5000 ft (railroad mile) that r.r. crews use to test a speedometer out.For example our first test mile here is mp.n.594.0 to mp.n.595.0.It must be clocked or checked with a stop watch,second hand or most motors these days has a built in stopwatch.It is 60 seconds for 60 mph., 1min.45seconds for 35 mph.,etc,There is a speed check chart in all timetables for this.A mile of 5280 ft would not check correct in this method.Also the pole count is for the engineer without a radio.All r.r. poles use to be 150 ft apart,or 3 coal hoppers apart. Which should be around 33 poles(on the N&W).But now most r.r.'s have been taking poles down.The ones that you see that have been left up or cut in half ,have had a public utility of some type on it,and is maintained by that company and not the r.r.[swg]

Obviously I'm not a railroader, but that doesn't seem right. If you were doing a true 60 mph, in 60 seconds you'd pass 5280 feet, not 5000 feet. If rr's used a 5000 foot mile and didn't want their speedometers to be off, all the speedometers would have to be based on a 5,000 foot mile, and I don't see any reason why a railroad would do that.

[ValleyX]

Originally posted by mackb4

A measured mile is the one mile distance of 5000 ft (railroad mile) that r.r. crews use to test a speedometer out.For example our first test mile here is mp.n.594.0 to mp.n.595.0.It must be clocked or checked with a stop watch,second hand or most motors these days has a built in stopwatch.It is 60 seconds for 60 mph., 1min.45seconds for 35 mph.,etc,There is a speed check chart in all timetables for this.A mile of 5280 ft would not check correct in this method.



??????? Where in the world did THAT come from. I don't mean to flame you but. . . .
A railroad mile is 5,000 feet? I don't hardly think so. If it were, I'm certain that would be spelled out in the rulebook someplace and everyone would either know it or be taught it. They're certainly 5,280 feet long on my division. Why wouldn't a standard mile check correctly? Take your stopwatch out on the freeway and run some speed checks and see if 60 is 60 and then check your railroad test mile, run your footcounter while you're at it.

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