FRA Track Classes

[gokeefe]

I asked a question on the "Downeaster Trackwork/Siding" thread regarding FRA Track Classes:
http://www.railroad.net/forums/viewtopi ... &start=195

I'm posting here to see if I can get a clearer answer.

Is there a difference between FRA Class IV and FRA Class V track other than the requirement for Automatic Train Stop/Positive Train Control?

According to the following website there didn't appear to be one:

From the Truman Area Community Network (TACnet), Henry County, MO. (This page is the #1 result on Google for "FRA track class requirements")
http://tacnet.missouri.org/history/railroads/fra.html

The website doesn't talk about any other requirement than ATS/PTC. I have always understood FRA track class designations to have implications over and beyond just gauge consistency and speed restricting systems. However they aren't mentioned in the quoted passage of the CFR.

[DutchRailnut]

Signal system/cab signal has nothing to do wirth track class
It does have to do with Max speeds however , for 80 mph and greater you need a cabsignal/atc/ptc system

PART 213_TRACK SAFETY STANDARDS--Table of Contents

Subpart A_General

Sec. 213.9 Classes of track: operating speed limits.

(a) Except as provided in paragraph (b) of this section and
Sec. Sec. 213.57(b), 213.59(a), 213.113(a), and 213.137(b) and (c), the
following maximum allowable operating speeds apply--

[In miles per hour]
------------------------------------------------------------------------
The maximum The maximum
Over track that meets all of the allowable allowable
requirements prescribed in this operating speed operating speed
part for-- for freight for passenger
trains is-- trains is--
------------------------------------------------------------------------
Excepted track.................... 10 N/A
Class 1 track..................... 10 15
Class 2 track..................... 25 30
Class 3 track..................... 40 60
Class 4 track..................... 60 80
Class 5 track..................... 80 90
------------------------------------------------------------------------

(b) If a segment of track does not meet all of the requirements for
its intended class, it is reclassified to the next lowest class of track
for which it does meet all of the requirements of this part. However, if
the segment of track does not at least meet the requirements for Class 1
track, operations may continue at Class 1 speeds for a period of not
more than 30 days without bringing the track into compliance, under the
authority of a person designated under Sec. 213.7(a), who has at least
one year of supervisory experience in railroad track maintenance, after
that person determines that operations may safely continue and subject
to any limiting conditions specified by such person.

[gokeefe]

Mr. Railnut,
Thanks for the response. So what is and where is the difference between Class IV and Class V? In the website that I cited the gauge requirements are the same.

I was left with the impression that the physical requirements between Class IV and Class V were not significant and perhaps a matter of discretion of the company of what speeds they wanted to run their trains and how much money they wanted to invest in signals.

[BR&P]

There are differences in the allowable tolerances between Class 4 and Class 5 track. Gauge is only one of many categories, some are the same and others are not. For example, under 49 CFR 213.63 the runoff in any 31 feet of rail at the end of a raise may not exceed 1 1/2 inches for Class 4, but may not exceed one inch for Class 5.

Crosslevel on tangent may not exceed 1 1/4 inch for Class 4, may not exceed 1 inch for Class 5.

There are numerous other measurements which vary from one to another.

Do a search for 49 CFR part 213 - that's the track safety standards. It will give you all the various parameters but since it pertains to track only, it won't address train control or signaling.

[gokeefe]

There are differences in the allowable tolerances between Class 4 and Class 5 track. Gauge is only one of many categories, some are the same and others are not. For example, under 49 CFR 213.63 the runoff in any 31 feet of rail at the end of a raise may not exceed 1 1/2 inches for Class 4, but may not exceed one inch for Class 5.

Crosslevel on tangent may not exceed 1 1/4 inch for Class 4, may not exceed 1 inch for Class 5.

There are numerous other measurements which vary from one to another.

Do a search for 49 CFR part 213 - that's the track safety standards. It will give you all the various parameters but since it pertains to track only, it won't address train control or signaling.

Mr. BR&P,

When you mention 'runoff' what exactly are you referring to? I'm assuming this is not drainage, standing water etc.

[BR&P]

Let's say you want to raise and tamp a section of track to make it smoother. For this discussion we're going to say that we're going to raise it 2 inches as we tamp. Now at the end of this segment where we leave off tamping, if you just stop tamping there's going to be a fairly sharp drop-off going back down to the untamped track. If you were to hit that at about 80 it would probably tickle your stomach like a roller coaster does.

So what you would do is at the end of the segment, continue tamping with let's say a 1 3/4 inch raise for a ways, then some more with a 1 1/2 inch raise, and so on so the track ramps back down gradually.

In reality a 2 inch lift is pretty hefty but I used it as an example to make it easier to visualize.

[gokeefe]

Thanks for taking the time to reply with the explanation. I learn something new everyday.

[D.Carleton]

Just to be clear, class five track plus cab-signals equals 80 MPH freight trains. Sorry to belay my own ignorance but are there 80 MPH freight trains out there? If so, with the coming of the PTC age, will there be more 80 MPH in the future?

[DutchRailnut]

There is not much class 5 track out there, 90% of all passenger routes are class 4 or even lower.
And 90% of all freight locomotives have max speed below 75 mph

[D.Carleton]

There is not much class 5 track out there, 90% of all passenger routes are class 4 or even lower.
And 90% of all freight locomotives have max speed below 75 mph

That's what I thought. I seem to remember a thumb-rule of 70 MPH max for TOFC/COFC trains.