Eastern Railroad Discussion > Is CSX getting away from 'advance approach' signal asp

Hello,

This one is for the signal gurus. Has anyone else noticed that on new signal installations, it seems CSX has started to get away from the 'advance approach' aspect (yellow/yellow)? In older installations, a train would receive an advance approach, followed by an approach, followed by a stop signal. In newer installations, such as Folkston, GA and Ellerslie, FL to name a couple, 'approach limited' (yellow/flashing green) seems to have taken the place of advance approach. For example, in Folkston, prior to the current signal installation, a NB train proceeding on the #2 track that had a stop signal at Burch would have an advance approach at Folkston, and an approach at the distant to Burch. Now, the same train receives an approach limited, an approach, and finally a stop signal at Burch. Has anyone seen any new installations where advance approach has been retained or added?

Thanks,
Troy



Edited 2 time(s). Last edit at 08/15/13 08:45 by CSXMAC.

CSX has been using Approach Limited as a "second yellow" on the resignalled portions of the former B&O in Ohio, too.



Edited 1 time(s). Last edit at 08/15/13 08:22 by toledopatch.

id say one reason is speed. if you get a adv app you don't have to being to slow down until you get to the approach, which a app ltd you have to be down to at least 45 when passing the app, then being immediately to under 30

I've not heard "advance approach" called on a CSX line in Ohio for a long time.

On the former C&O and CR lines, "yellow over yellow" is "Approach Slow", while on other CSX lines it is "Advance Approach". This may be one of the reasons why it's not being used, at least in this area, where you have multiple crew qualifications.

Speed wise, "advance approach" just says be prepared to stop at second signal, while "Approach Slow" says proceed, approaching next signal not exceeding slow speed. Slow Speed is defined as a speed not exceeding 15 mph.

CG



Edited 2 time(s). Last edit at 08/15/13 08:09 by CGTower.

And please, it's "Advance Approach"--no "d".

I worked for a railroad that still uses "Advance Approach" regularly. It is in use mainly because block length is shorter here--about a mile between block signals--and speeds can be as high as 70.

Carl Shaver
Lombard, IL

Yep, change made...that difference is important.

CG




toledopatch Wrote:
-------------------------------------------------------
> CGTower Wrote:
> --------------------------------------------------
> -----
> > I've not heard "advanced approach" called on a
> CSX
> > line in Ohio for a long time.
> >
> > On the former C&O and CR lines, "yellow over
> > yellow" is "Slow Approach", while on other CSX
> > lines it is "Advanced Approach". This may be
> one
> > of the reasons why it's not being used, at
> least
> > in this area, where you have multiple crew
> > qualifications.
> >
> > Speed wise, "advanced approach" just says be
> > prepared to stop at second signal, while "Slow
> > Approach" says proceed, approaching next signal
> > not exceeding slow speed. Slow Speed is defined
> as
> > a speed not exceeding 15 mph.
> >
>
> Actually, Y/Y as described above is Approach Slow,
> not Slow Approach. Slow Approach is R/R/>Y< or
> equivalent. Under speed signalling its meaning is
> to proceed at slow speed through interlocking
> limits, then approach next signal prepared to
> stop.
>
> Under other rulebooks that use route signalling,
> Y/Y means Approach Diverging.



Edited 1 time(s). Last edit at 08/15/13 08:12 by CGTower.

Over here on the eastern B&O recent re-signalling from CPL's has introduced (not gotten rid of!) the Advance Approach aspect. However, in some cases they use Approach Medium interchangeably with it rather than Approach Limited.

Signal logic without the 'logic' part!

Davis

Its been changing across the CSXT system, as they wanted to have ALL CSXT signals as one simple rule. hence replacing ex NYC, C&O, B&O, SBD signal systems.. That also includes the Water level Route from Berea-east to Selkirk.. Theres many old NYC signals are coming down in a rapid rate.. New signals are already up between Selkirk towards Lyons (Rochester approach) with few NYC "automatics" still up in smattering areas. They are to proceed west of Rochester next year.

CR

I had the impression that CSX was phasing out the Advance Approach aspect too, but there are cases where it can be useful and it appears they are applying it in such cases now in new installations. For example, if there is a benefit to informing the train crew that they will be stopping at the second signal ahead, but block lengths are sufficient that no speed reduction is necessary before reaching the signal displaying Approach, an Advance Approach can be given. Also, at the distant signal to a control point with a Limited Speed crossover/turnout followed by a block with a safe braking distance for speeds between maximum and Limited Speed, they could use:
Approach Limited >> Limited Clear >> Clear (to cross over) and Approach Limited >> Approach >> Stop (for straight route)

or they could use:
Approach Limited >> Limited Clear >> Clear (to cross over) and Advance Approach >> Approach >> Stop (for straight route)

The second example would give the crew more specific information about what to be prepared for at the next signal. Of course in speed signaling such a differentiation isn't necessary, but practically, sometimes it's useful to the crew to know their routing ahead of time. Either way, I still have the impression that Advance Approach will continue to see only occasional use on CSX in new installations, but time will tell.

Dave Malohn

I asked this same question the last time I rode with an Amtrak crew. The engineer, who had previously worked for CSX, said its mainly to get the train slowed down approaching the next signal.

They also seem to use it prior to "approach medium". Coming south into Charleston, Amtrak will normally get an Approach Limited at Hanahan, then an Approach Medium on the intermediate, then either a Medium Clear or Medium Advance Approach at Meads crossing over to the #2 to work Charleston. This is if the dispatcher doesn't just put the train on #2 at Hanahan.

Posted from iPhone

Tim Rich
S. Ogden, UT

1 Wrote:
-------------------------------------------------------
> id say one reason is speed. if you get a adv app
> you don't have to being to slow down until you get
> to the approach, which a app ltd you have to be
> down to at least 45 when passing the app, then
> being immediately to under 30


Well I can't speak for NS's Advance Approach but on CSX (Former Norac signals) you do have to approach the next signal at limited speed (45mph) being prepared to stop at the second signal. Personally I hate the fact they are phasing out the advance approach, you knew you were stopping two signals ahead. With the approach limited, when you get it at certain signals, ex.distant signals for interlockings, you don't know if you're crossing over or just following someone. Another example is the same situation above, but now add in a work authority, you don't know which track your going to take through the foremans area and some foreman don't like to give permission until you tell them which way your going. Taking away the advance approach signal just adds unneeded confusion, just like when they took away the "A" boards that told you you were approaching a work authority. The warning boards they use now are a catch all for everything which personally I think is a joke.

The symbol formerly known as Q122 is out



Edited 1 time(s). Last edit at 08/15/13 17:24 by CSXQ122.

Look at the CSX rule book. With up to three different "heritage" signal systems (CR, ACL, SBD, ++), they are moving to uniform aspects and indications across the system, to eliminate ambiguity. "Approach Limited" Y/FG means the same across all three; approach the next signal at 45 mph. It is typically (but not always) used in advance of a diverging move, in which case the next signal would likely be "limited clear"(45mph),"medium clear" (30 mph), or "slow clear" (15-20 mph) depending on the curvature of the turnout and track conditions ahead. The Y/Y indication had significant, and potentially confusing, differences in meaning, depending on the protocol of the previous road; "advance approach" allowed normal speed, but "prepared to stop at second signal" in the case of one or more of the predecessors, but "approach slow" on one or more others, "proceed approaching next signal not exceeding slow speed". My personal preference would be for uniform aspects and indications across all railroads. There are still too many indications for the same aspect in different parts of the country where an engineer crossing from one road to another on trackage rights can be confounded by different meanings for the same aspect. This anomaly caused a collision some years ago near Chicago on Conrail.

CSXQ122 Wrote:
-------------------------------------------------------
> 1 Wrote:
> --------------------------------------------------
> -----
> > id say one reason is speed. if you get a adv
> app
> > you don't have to being to slow down until you
> get
> > to the approach, which a app ltd you have to be
> > down to at least 45 when passing the app, then
> > being immediately to under 30
>
>
> Well I can't speak for NS's Advance Approach but
> on CSX (Former Norac signals) you do have to
> approach the next signal at limited speed (45mph)
> being prepared to stop at the second signal.
> Personally I hate the fact they are phasing out
> the advance approach, you knew you were stopping
> two signals ahead. With the approach limited,
> when you get it at certain signals, ex.distant
> signals for interlockings, you don't know if
> you're crossing over or just following someone.
> Another example is the same situation above, but
> now add in a work authority, you don't know which
> track your going to take through the foremans area
> and some foreman don't like to give permission
> until you tell them which way your going. Taking
> away the advance approach signal just adds
> unneeded confusion, just like when they took away
> the "A" boards that told you you were approaching
> a work authority. The warning boards they use now
> are a catch all for everything which personally I
> think is a joke.
>
> The symbol formerly known as Q122 is out


There is discussion going on to have a different type of advance board for work authorities. I agree with you about the approach limited indication at distant signals to interlockings and work authorities.

A new signal upgrade project at Holland MI uses Advance Approach. There are control points for two legs of a wye located within a mile long siding. Trains will see two Approach Slows then Advance Approach ahead of the usual Approach and Stop.

PRR1361 Wrote:
-------------------------------------------------------
> Look at the CSX rule book. With up to three
> different "heritage" signal systems (CR, ACL, SBD,
> ++), they are moving to uniform aspects and
> indications across the system, to eliminate
> ambiguity. "Approach Limited" Y/FG means the same
> across all three; approach the next signal at 45
> mph. It is typically (but not always) used in
> advance of a diverging move, in which case the
> next signal would likely be "limited
> clear"(45mph),"medium clear" (30 mph), or "slow
> clear" (15-20 mph) depending on the curvature of
> the turnout and track conditions ahead.

In true speed-style signaling, a-la NORAC, APPROACH LIMITED would not precede anything but LIMITED CLEAR. APPROACH MEDIUM precedes MEDIUM CLEAR (or MEDIUM APPROACH) and APPROACH SLOW precedes SLOW CLEAR (or SLOW APPROACH).

BTW, there is no such thing as LIMITED APPROACH in true speed signaling, as the APPROACH indication requires slowing to 30 MPH, so the 45 MPH allowed by the track geometry is moot.

NORAC signaling actually is very intuitive if you break the names down: First word is what you do NOW, second word what you do LATER, at the next signal or after clearing the interlocking.

For example, APPROACH LIMITED --- You gotta APPROACH the next signal...how? At LIMITED speed (45 MPH). At the next signal (LIMITED CLEAR) you proceed how? LIMITED speed right now through the interlocking, then proceed on a CLEAR to the next signal.

Hope that was helpful. I'll stop now before I get started on the relative merits of how CSX comes up with, then can't make up their mind on, their operating practices.

NZ
Who has taught a few rules classes here and there.

Hi NZ,

Is what you wrote in your first paragraph the base philosophy of the NORAC rules committee? I'm curious because I don't think that philosophy is "true" speed signaling. I would argue that in true speed signaling, it makes no difference whether you're diverging at the next signal or just slowing down for an upcoming stop - you reduce to the speeds the signals tell you to. I don't see any problem with straight-route sequences like Approach Limited >> Approach Medium >> Approach Slow >> Approach >> Stop in short block territory because I think it's less confusing than the alternative, which I guess in that long example would be repeated Advance Approach and Approach aspects.

And even if that is the philosophy of NORAC, the members don't follow it closely. Amtrak, NS, Conrail, and New Jersey Transit all have instances where they use Approach Limited, Approach Medium, and Approach Slow aspects to slow trains coming up to Approach + Stop signals on straight routes (i.e. not just Advance Approach into an Approach). I think it comes down to the specific block lengths and whatever sequence fits the best.

For the Limited Approach, I agree with what you said with respect to NORAC, but that's because NORAC requires a reduction to Medium Speed when passing an Approach signal. Not every railroad requires that, so Limited Approach becomes an option. It is curious that CSX doesn't require a further reduction to Medium Speed after passing a Limited Approach signal like they do for an Approach, but I assume they didn't feel it was necessary.

Dave Malohn

FYI guys (and gals): NS ain't NORAC anymore, effective 1/1/12. They are using a single consolidated rule book for all subsidiaries, and it does not in any way look like NORAC except in very limited areas, such as CR signal aspects. Besides, there's no way Norfolk SOUTHERN is going to continue to have anything NORTHERN (as in NORac) on any official documents, y'all!

With the signal upgrades on the old C&O in the Richmond, VA area from C&O signals to seaboard style signals Advance Approach is commonly used now.