Archive for the ‘Dark Territory’ Category
I have been fortunate during my corporate management and consulting careers to take on and succeed with a wide assortment of assignments for which there was little to no precedence including the following:
• Architect of the first overlay Positive Train Control (PTC) system;
• Development of mathematical, financial, & liquidation analyses for the resolution of the bankruptcy of the Penn Central Railroad; the largest bankruptcy until that time;
• Development of a mathematical model for the blending of ferrous scrap to minimize the cost of electric furnace steel production;
• Development of an econometric model for the U.S. ferrous scrap market;
• Development of a computerized train crew management system;
• Design of a virtual Centralized Traffic Control (VCTC) system design for Kazakhstan’s and Egypt’s railroads; a system applicable to a wide variety of global passenger / freight rail operations including token-based, dark (non-signaled), and CTC railroads;
• Development of a wireless strategy for the U.S. rail industry based upon supply and demand;
• Development of a strategic Enterprise IT Architecture (EITA) for the U.S. intermodal industry;
• Development of an EITA for a generic railroad.
While the above list of engagements is diverse, the same primary, fundamental development concept contributed to their successful completion. That is, the more complex the challenge was, the easier it was for me to complete the assignment. That is, I have consistently taken a pragmatic, 80/20 approach to avoid the unnecessary, overly complex design issues that contribute very little value (20%), but that prevent others with their 100% perspective of being successful. The success of the 80/20 approach is directly dependent upon the ability to make the proper assumptions to avoid over-thought garbage – and then to revisit those assumptions once the air has cleared. There are two complimentary points that permitted me to be successful. First, I was in charge and could drive the solution to completion with little interference. Second, I was fortunate to identify and include excellent associates that were willing to support my efforts; it was usually a team effort. But, what happens when there is not an objective team and/or no rational (80/20) individual who is in charge? For example, consider the Federal Railroad Administration (FRA) and the Interoperable Train Control (ITC) committee relative to PTC and the concept of vitality.
To start with, it is necessary to define vitality in that there is a significant amount of misunderstanding across the industry, including management, regulators, and suppliers. So! Vitality is the process that is used to ensure the integrity of train movement authorities, i.e., only one train within a specified track segment at any time. In CTC operations, the vitality is within the wayside infrastructure of track circuits and control points. In Dark territory, vitality is the train sheet whether physical or computerized (conflict checker software). For some ex-colonies of the British empire, e.g., Egypt, vitality is the approach that provides for a physical token to be delivered to the driver, it can be that simple. However, to be clear vitality does not include the delivery of movement authorities, e.g., signals, cab signals, voice/digital transmission, or tokens.
Starting with the FRA’s Rail Safety Advisory Committee (RSAC) that took on PTC over a decade ago, there was the ongoing challenge on my part to obtain a common understanding that PTC is NOT “Vital” since it is not involved in the generation of authorities. The reason to make the distinction was driven primarily by my concern that undue risk analysis and system design would be sought by the FRA, if not suppliers and railroads, for PTC’s safety enhancement functionality that had no effect on the “vitality” of the railroad’s operations. My approach was to describe “functional vitality” in addition to “equipment vitality” that is associated with CTC wayside infrastructure. The functional definition was required to address how movement authorities are generated in non-signaled, “Dark”, operations since conventional suppliers have little to no experience with Dark. Hence, they will state that there is nothing “vital” there in that they only deal with equipment vitality. This “equipment” perspective made it too convenient for the FRA to fatuously associate the concept of vitality with PTC equipment while ignoring the concept of functional vitality for Dark operations.
FRA was not alone in abusing the vitality perspective. Specifically, the Interoperable Train Control (ITC) committee was also guilty of pursuing a non-pragmatic perspective of PTC presumably based upon what they thought was necessary for a seemingly vital system. This group of conventional Class I engineering and operational individuals, that were charged with designing an interoperable PTC perspective for the U.S. rail industry, far exceeded the necessary requirements for a non-vital PTC. I offer the following: 1) development a positioning accuracy for PTC that was totally ridiculous, i.e., 18 cm with 10-9 confidence level, 2) integrated the need to enforce to Intermittent Signals (ISs); and 3) forced the implementation of a parallel wireless data infrastructure without developing a data model for PTC and thereby not identifying alternatives that should have been considered. These were serious engineering design errors that resulted in a tremendous increase in the capital investment, on-going maintenance costs, and implementation time to install PTC across the industry. Additionally, ITC failed to take on the requirements for transits and commuter operations. An example of this ITC’s purposeful exclusion (ignorance, arrogance?) is the inability of the current PTC design to prevent the recent accidents due to trains over-speeding in passenger terminals. To be clear, such prevention requires no additional investment to that of PTC along the mainline. The solution requires only the addition of GEO-fencing for trains entering terminals. But, ITC’s lack of integration of the transits and commuter railroads in their activities means that such situations will not be included, at least in the initial rollout of PTC.
Now, FRA has made a declaration of “Vital PTC”. Some of the material I read on the FRA Website that discussed vital systems also had PTC enforcement functionality and were branded as Vital PTC systems – which they clearly are not. Rather, they are Vital Systems (traffic control) with integrated PTC-type functionality. How desperate is the FRA to make such inappropriate associations?
Along this same line of thinking, perhaps FRA is presenting the Vital PTC perspective in that the on-board PTC platform can also display digital authorities via the wireless data platform that PTC requires for its functionality. Hence, FRA considers this to be Vital PTC. However, there is a primary fallacy here. That is, the transmission of authorities, whether verbally, visual (signals), or electronically is NOT a vital function. Such transmission and display is safety critical at best, i.e., one wants such transmission and display to be highly reliable, but if it fails then the engineer resorts to the underlying vitality of any railroad. i.e. the Book of Rules.
I am encouraged by recent conversations with colleagues that the railroads are now pushing back on FRA’s declaration of “Vital PTC”. Welcome to FRA’s La La Land.
In the previous posting on this blog, I wrote about the Innocent Lost of Engineers, meaning that with the introduction of the commercially-available, hand-held digital calculators in 1972, engineers began to lose their ability to approximate solutions for a series of calculations with various powers of ten involved. For example: engineers of that generation could quickly determine that 3.936 X 44,888 / 1,987 is somewhere in the range of 4x(90×500)/(4×500) …hence … 4×90/4 … hence … 90. Such capability was an art that complemented the use of the now-obsolete slide rule, an analog calculation device that performed multiplication and division by literally sliding sticks ruled with logarithmic scales. This lack in the skill of approximation for engineers not experienced with the slide rule is unfortunate because it is critical for thinking on one’s feet to obtain answers to move through complex situations efficiently, albeit not accurately. I also believe the ability to approximate solutions adds greatly to one’s level of creativity. Unfortunately, engineers of today feel compelled to deliver exactness limited by the number of digits displayed on their digital device. Their answer for the above problem would be 88.91754806240564…
Considering railroads, I see a significant lack of creativity with the current set of primary technicians across the industry as to their inability to “think outside of the boxcar, if you will. A case in point here is the pursuit of PTC in the U.S. where technicians are designing to extreme levels of exactness and capability that are clearly not warranted (see posting The Goods, The Bads, & The Uglies, March 5, 2013 found by clicking on the PTC category on the right side of the home page).
Now, I suggest that railroad operators are in the process of losing their innocence as well as to how they run their railroads. Fortunately, however, this is a good thing. Instead of operating a railroad as they have in the past to satisfy their own perspective of what a railroad is, i.e., take it or leave it, railroads are focusing now on customer service for the benefits of their own bottom line as well as that of the shippers by improving customer service. This customer / bottom line perspective started to evolve in the 80s as railroad executives began to recognize the increasing amount of freight traffic being captured by the trucking industry via the nationwide interstate road infrastructure. As a subject for a posting in the future, this was the genesis of the intermodal industry that has now replaced coal freight revenue as the top source of revenue for several Class I railroads.
As to operators losing their innocence, I see 4 phases that will permit them to eventually maximize the use of their resources while delivering optimal customer service.
- Resource Rationalization
- Scheduled Operations
- Proactive Resource Management
- Industry Management Perspective
Unfortunately, as explained below, most of the major U.S. railroads have only managed to achieve the first phase of resource rationalization in the last 2-3 decades. Too few railroads have begun to pursue the 2nd phase of scheduled operations, yet alone the 3rd phase of proactive resource management, and certainly not the 4th phase of industry management perspective.
1. Resource Rationalization
This phase began with the signing of the Staggers Act in 1980 that deregulated the freight rail industry in the U.S. This act introduced competition to the freight rail industry by removing the role of the now-defunct Interstate Commerce Commission (ICC) that regulated the tariffs for freight services. This first phase was managed via the infusion of MBAs in the railroads that struggled to work within the efficiency constraints of conventional traffic control systems and the associated operating processes. Such constraints included being confronted with the mindset of operators that fatuously believed that running a railroad without a true schedule was a test of their management skills. That is, a train schedule was something that was handed down to them by the ivory tower Service Design department staffed by MBAs, as “wouldn’t this be a great way to run a railroad”. But, a true operator was not being measured by such performance, but rather by his ability to work with conflicts as they occurred in traffic movements. Hence, what the MBAs provided at that point was limited to an analysis of contribution of individual rail corridors as to the railroad’s bottom, although that analysis was based upon non-scheduled operations. The result of their efforts was the shedding of rail corridors with less than acceptable performance. Unfortunately, the other primary assets, e.g., locomotives, rolling stock, crews, yard operations remained untouched as to their inefficiencies.
2. Scheduled Operations
The railroads are now into the second phase of losing their innocence with the advancements in technologies, most importantly wireless data an virtual positioning, that can provide for more timely and aggressive handling of train movements by simply knowing where the trains are AND at what speed they trains are traveling. For most railroads in the U.S., they have only begun the process of deploying the necessary wireless data networks that can provide such data. It should be understood that this wireless deployment is not due to a strategy on the part of most railroads, but rather it is a deployment due to the Federal mandate to implement PTC, a system that requires a wireless data network. I dare say that without that mandate, a number of railroads would still not being deploying such data networks due to a lack of operating strategy linked with a technology strategy (a.k.a. strategic railroading). For example, to my knowledge only 2 railroads in the US had such a strategy before the mandate to deliver the data required to improve the efficiency of their crisis-based dispatching processes.
With this additional level of timely and accurate train position and speed data, the challenge of efficiently dispatching trains increases beyond the mental capability of any dispatcher to deal with all of the variables in dense corridors. One should understand that effective dispatching until this time had been an art based upon not only the mental capabilities of the dispatcher, but also by his/her degree of experience with a particular corridor. And, based upon the principle that one can not effectively manage dispatching if one cannot measure the efficiency of dispatching, then I suggest that no major railroad had, and perhaps has, any effective measurement technique as to the efficiency of its dispatchers. Maybe, they think they do, but most likely it is based upon the conventional concept that a dispatcher should not make the same mistakes that s/he made yesterday, or the day before, or the week before, whatever.
Operating to schedule is not just about track time efficiency. Class Is are beginning to realize that the ability to run to schedule can result not only in better customer service, but also in a substantial reduction in the “slack resources” (a mathematical phrase when optimizing operations) that sit idle so as to permit some level of efficiency when locomotives are not where they need to be … or train crews outlaw … or the designated yard has insufficient in-bound tracks, etc. Simply stated, the unstructured inefficiency of depending upon the use of slack resources in a crisis-based, truly non-scheduled fashion is substantially greater than running to a schedule where slack resources are kept to a minimum to handle a substantially less level of conflicts when the schedule is corrupted…which is more the case than not.
3. Proactive Resource Management
This next phase is that which only 2 Class Is to my knowledge have taken on. I introduced PTM a decade ago based upon a very simple construct. That is, in order to minimize conflicts of mobile assets, then wireless data is required to provide the timely and accurate data of where those assets are AND at what speed they are traveling. With such information, then mathematical planners (basic algebra) can be used to predict where conflicts will occur. With that knowledge, then Operations Resource (OR) tools can be used that identify objective functions to minimize the consequences of those conflicts. For example, an objective function may be to reduce the travel time, or to maximize train velocity, for the set of trains being considered for a particular corridor, or for a set of corridors. Conventional CTC that is used across 50% of the U.S. freight rail trackage can only provide block occupancy with no knowledge of speed. For example, did that intermodal train come to a stop, and therefore the opposing merchandise is train being held on a siding for no reason? The other 50% of the freight trackage is dark territory where the dispatcher doesn’t even know which the block the train is in, yet alone the speed. Simply stated, PTM provides for flexible block operation (which is far short of the complexity, if not the questionable possibility of moving block) instead of the inefficiency of fixed block operation where trains vary significantly in length and speed. For further information on PTM, I suggest you read the posting Degrees of Separation, December 26, 2012 in the category Railroad Business found on the right side of homepage.
4. Industry Management Perspective
There is a 4th phase, which has yet to be initiated, that addresses the efficiency of the industry, and not just an individual railroad. The underlying point here is quite straightforward, but yet continues to be ignored. That is, given the substantial necessity of trains across U.S. railroads to operate within a specific region, yet alone to go from coast to coast, it is impossible to achieve the highest level of scheduled railroading if the interconnecting railroads are not running to schedule. So, there is a Catch 22 in that a given railroad cannot operate at its highest level of efficiency until the interconnecting railroads are running to schedule, but those railroads cannot operate to schedule until the given railroad is operating to schedule.
I see 2 requirements to break into this circular logic. First, the increasing use of PTM will narrow down the complexity of the interconnection challenges. Second, and most important, the annual bonuses of railroad executives need to be structured to place emphasis on industry efficiency, and not just the efficiency of their individual railroad.
Lastly, for the majority of railroads in the U.S., as well as for a number of low density corridors in the Class Is, there is still an issue of considering how wireless data, virtual positioning, and on-board intelligence (such as that being provided via the implementation of PTC), can replace their current dark territory and low density CTC operations with Virtual CTC (VCTC) as described in other postings, including videos, on this blog (click on the VCTC category on the right side of the homepage).
All of the above is really quite straightforward to understand, but the traditionalists of railroads have yet to grasp that a paradigm shift is available to them given a shift in the core technologies that is available to them: again, wireless data, virtual positioning, and on-board intelligence.
With the introduction of overlay PTC just over a decade ago, the concept of vitality needed to be expanded at that point beyond the mantra of signaling engineers as to a vital component or system being one that fails in a safe manner, i.e., failure without introducing any additional risk. In addition to this design vitality, it was necessary to introduce a concept of functional vitality to prove that PTC was and remains not vital. That is, a functionally vital entity is one that generates the movement authorities for trains, thereby providing for the integrity of train movements. For signal engineers the two concepts are inseparable, and in their viewpoint, anything associated with traffic control must by vital. Such fatuous rationalization can be quite unfortunate for the deployment of advancing technologies in railroads, including PTC. Two current examples here are ITC’s efforts in designing the wireless and positioning platforms for PTC that are way beyond what is required for a non-vital system, if even a vital one.
In anticipation of such design tangents by railroad technicians ( as demonstrated in the past by UP with it Precision Train Control project that died from overdesign), I introduced the functionally vital perspective a decade ago to demonstrate that overlay PTC is not vital and therefore not subject to the design and regulatory complexities associated with vital systems. Stated otherwise, PTC’s ability to enhance the safety of rail operations is substantially less critical than that of the traffic control systems that provide for the integrity of train movements. PTC only addresses human errors whereas traffic control systems are absolute.
Being the architect of the first overlay PTC system, I was continuously challenged during the early years by labor, FRA, suppliers, and even my counterparts on other railroads, to explain why PTC is not vital. The forum for these discussions was primarily that of the Rail Safety Advisory Committee (RSAC) for PTC that was charged with defining the core objectives of PTC. Understandably, RSAC-PTC was primarily manned by signal engineers who live and breathe vitality with their natural inclination being that everything is vital. Again, for them PTC had to be vital, I assume, because it addresses safety, and it is related to vital traffic control systems. At the same time, signal engineers when asked during the courses I teach on PTC and railroad operations “What is vital in dark territory?”, will respond that there is nothing vital since there is no wayside equipment. The solution for addressing both of these ill-structured mind-sets of signal engineers as to PTC and dark territory was to provide the functional definition of vitality that really goes to the core of running a safe railroad, i.e., the generation of authorities.
In parallel with the functional vitality effort was the extraordinary task of convincing the masses that PTC did not deliver those business benefits that continue to be so widely and wildly proclaimed by FRA and suppliers as to increasing traffic density and the efficiency of the key operating assets, e.g., crews, locomotives, and even maintenance crews. I quote the FRA’s website “In addition to providing a greater level of safety and security, PTC systems also enable a railroad to run scheduled operations and provide improved running time, greater running time reliability, higher asset utilization, and greater track capacity.” Here is the simple, and one would think very obvious, logic as to why overlay PTC can’t provide such business benefits. To increase traffic density means that the generation of movement authorities need to be done more efficiently … and since PTC does not generate movement authorities (nor deliver them as the FRA website proclaims – that is the purpose of digital authorities – not PTC), then it cannot provide those benefits. Actually, if not properly designed, PTC can actually decrease both the traffic density and safety by making unnecessary enforcements. What the FRA and others who flaunt PTC business benefits refuse to understand is that it is the wireless data path required by PTC that also permits train tracking status data to be delivered to back office management systems. As demonstrated by NS and BNSF at least, a railroad doesn’t need PTC to obtain the stated business benefits; a railroad only needs a wireless data platform, whether it be cellular, satellite, and/or private. In any event, the bottom line remains, i.e., PTC is not vital in any sense.
OK, at this point you may be thinking about VPTC (where V means vital) which is one title given to the PTC systems being pursued by the freight and commuter railroads. Clearly such a title suggests that PTC is vital, but it isn’t. VPTC means that the platforms upon which those PTC systems are deployed are design vital so as to reduce the failure of the PTC system, but PTC is still not functionally vital. The purpose of VPTC is to provide a pragmatic economical solution to regulatory issues that requires a restricted speed for a train should its PTC platform fail. In heavy density corridors, the application of restricted speed could result in significant business costs.
With the distinction between design and functional vitality now established above, I introduce a new vitality phrase: “Vital Employee”. Simply stated, a vital employee is one that generates a movement authority. For U.S. railroads, the primary example is the Employee-In-Charge (EIC) that provides the authority to a train to move through a work zone, a work zone that is encapsulated (nested) within an authority generated by a traffic control system. Handling the enforcement of the nested EIC authority was a major design issue that I had to provide for the first overlay PTC system … and is now used by the PTC systems being deployed by the freight railroads. Again this was done in a non-vital way by not affecting the underlying Method of Operations, thereby avoiding regulatory complexities.
The vital employee perspective has proven to be particularly challenging in my assignment as Project Leader for a consulting effort in Egypt to advance both the safety and efficiency of the majority of the Egyptian National Railways (ENR) operations that use token block and TYER, a.k.a. British Absolute Block, traffic control systems. In the case of ENR, their operations have mechanical interlockings that are handled by operators independent of the central movement office. Instead of a centralized dispatcher, ENR uses block/interlocking operators to generate block-by-block authorities thereby compromising the efficiency and safety of train movements compared to that which railroads around the world achieve with dark and signaled operations. For this engagement, a “virtual” CTC (V-CTC) system is being designed that will provide for multiple block authorities subjected to nested, manual interlocking authorities. This solution provides for enforcement for the authorities generated by both V-CTC as well as the interlocking operator.
As a closing point, I wish to remind all that the Book of Rules provides the underlying threshold of vitality for all rail systems. In my 40+ years in the industry, I find that too many tend to ignore this point – just as signal engineers tend to ignore dark territory.
In a previous posting on this blog, Hey! Watch This, I reported on some of the findings stated in the U.S.’s General Accounting Office (GAO) report on PTC dated December 2010. The bottom line of that report was that the cost / benefit ratio over 20 years for implementing PTC is hovering around 20/1; an absolutely unacceptable criteria for private investment. And yet, that is the burden, the cost of doing business, for the freight railroads it seems. For the commuter and regional rail systems that require public funding to stay in gear, the challenges of obtaining the necessary funding are likely to be even more severe. Given these circumstances, the question needs to be asked as to what can be done (other than obtaining Federal funding) to make the cost/benefit ratio more reasonable.
The opportunities to obtain a more reasonable cost/benefit ratio fall into three categories obviously, i.e., reduce the costs, increase the benefits, or do both. Until now, the only focus has been on increasing the benefits. However, as I have noted in the referenced posting, as well as others on this blog, there are no business benefits directly associated with PTC; PTC is only a safety-enhancement system. Those fatuous attempts by either naïve or mischievous individuals to identify business benefits have been rejected mostly by now, with only the occasional exception as discussed in my posting, Really! You Gotta Let It Go. So, the safety benefits that have been identified for PTC are all that there are.
So! If the benefit denominator of the cost/benefit ratio can’t be increased, then the only option is to decrease the cost numerator. Interestingly, there are three very significant ways to do that, although they still may not provide a reasonable cost/benefit ratio. The first possibility, again, has been addressed on this blog already. I am referring to tightly integrating the PTC platform with an IT / wireless data platform to provide a mobile node architecture for a railroad’s management system just as a manufacturer would do with fixed nodes to manage its facilities. The second possibility to reduce costs is to go after the wireless infrastructure that is being developed by the Class Is. As also addressed on this blog, this network is a tremendous overkill for what is needed for PTC as currently structured. And as will be described immediately below, the wireless infrastructure is even more irrational if the third method of reducing costs is taken into consideration, i.e., significantly reducing the number of Wayside Interface Units (WIUs).
Why Oh Why the WIUs ?
The implementation of PTC requires 4 primary components.
1. On-board PTC platforms (clients);
2. A back-office PTC platform (server);
3. Wayside interface units that provide for the interchange of data between the critical wayside infrastructure components and the PTC clients / server; and
4. A wireless communication network to deliver the necessary data between the other 3 components.
There simply is no way to reduce the number of PTC clients or to eliminate the server. However, when it comes to the WIU’s there is in fact a major opportunity to minimize the number of units required, that is if one doesn’t accept what is being said by the industry. Specifically, the estimated number of WIUs that will need to be installed to implement PTC across the U.S. has gone from 75,000 for shock value by the freight railroads following the mandate, to the current estimate of 50,000. Now, with the recent agreement by the Obama Administration to reduce the amount of trackage requiring PTC by 10,000 miles, due to changes in traffic by 2016, the estimated requirement for WIUs is probably now around 45,000. But, the kicker is that such a number is still way too high, at least from a regulatory standpoint.
To understand what can be done to reduce the WIU requirement first requires understanding the functionalities that are provided by the use of WIUs, as follows:
1. Reporting status of a manual switch to the PTC server for routing a train in dark territory;
2. Reporting status of a manual switch to the PTC server or clients for supporting enforcement of a train to prevent unauthorized movement through a misaligned switch;
3. Reporting aspects of the control points to the PTC server or clients so as to set up the “targets” for possible enforcement; and
4. Report aspects of the intermediary signals (ISs) to the PTC server or clients so as to set up the “targets” for possible enforcement.
There is a 5th functionality supported by the use of WIUs that is not directly associated with PTC deployment, i.e.
5. Permitting the operator to operate a switch remotely from the locomotive either within the train’s authority if PTC is operable, or without checking for authority should PTC not be available.
Now, like everyone else, did you accept #4 regarding ISs without question? In fact, to incorporate ISs into PTC functionality is not a regulatory requirement of PTC. Additionally, not only does incorporating ISs into PTC not provide any true advantage, but one could argue that to monitor ISs could become more of a hazard than a benefit, as well as a source for decreased velocity, due to the increase likelihood of false enforcements.
Note: the issue of false enforcements is primarily due to the significant variance in determining the braking curve necessary for enforcement, thereby possibly enforcing the train to a stop when it fact the operator could have managed to handle the train properly.
So, why have ISs been incorporated into the PTC platform? It all stems back, in my opinion, to one individual at one Class I who took the dark territory solution for PTC for which I was the architect at CSX, and put a non-pragmatic signal territory spin on top of it. However, it may go deeper than that it seems. Just as with the resistance that existed by Labor to reduce the trackage that requires PTC by 10,000 miles, as noted earlier, it seems that Labor has had its hands in the design of PTC as well. I guess it comes down to jobs. In short, not only is PTC not a rationally justified safety system, but there is an irrational level of infrastructure being required to satisfy Labor.
I am not quite through as to reducing the use of WIU’s. I now look at point #3 as to the WIUs for control point. The point here is that the control points are already connected to the CAD platform via a wireless or wired pole line. These communication links provide the same data to CAD that are required by PTC. That means that WIUs are not required for control points either in that the code line infrastructure can be tapped by the PTC server at the back office to get the information required to generate targets. Wait, I am still not done with reducing the number of WIUs.
Consider point #2 as to ensuring no movement through a misaligned switch. This situation is somewhat similar to the approach I developed for handling work gangs and the Employee in Charge (EIC), which by the way is the approach being used for PTC by the freight railroads. That is, the on board PTC client notifies the operator of the train’s approach to a work gang and requests that s/he indicates via the on board PTC display whether or not s/he has approval provided by the EIC to proceed into the work zone. If no positive response is received by the PTC client within certain distance / speed / time parameters, then an enforcement is made. This same approach could be used to notify the operator of an upcoming switch and to request an input by the operator that s/he can verify that the switch is properly aligned. Again, as with the work gang, if a positive response is not received within a certain combination of distance / speed/ time, then an enforcement is made. While this approach may seem a bit awkward, it is in fact a solution that is directly aligned with the operating rules.
Finally, as to point #1, the use of WIU’s for routing trains in dark territory. Actually, that one is still appropriate in that it was the solution I conceived for the development of PTC at CSX. As mentioned above, that PTC project was for dark territory and the other alternatives for routing trains at that time were too outlandish and/or too expensive, including the failed pursuit by the joint venture of GE and Harris to deploy Precision Train Control (not positive train control), a vital, moving block operation.
One last thought here. If indeed the railroads were to greatly reduce the number of WIUs based upon the above, then the cost of the wireless network would be significantly reduced as well, me thinks.
I await your comments.
Recently on this blog I posted the article Dangerous Railroading in which I identified 4 primary areas that a railroad needs to address for safe operations, i.e., 1. choice of safety systems deployed, 2. critical infrastructure maintenance practices, 3, personal / personnel accountability, and 4. theft of critical infrastructure. The primary point of that posting was that a railroad’s slack in any one of the four areas would result in the safety of its operations being readily compromised. In that posting I addressed each of the areas in a cursory fashion with the commitment that I would address each in greater detail in subsequent postings. As such, this posting addresses safety systems with additional discussion as to Traffic Management.
There are two levels of safety systems to consider for the movement of trains from both the dispatching and train crew’s perspectives, i.e.. traffic control and enforcement, respectively.
Simply stated, traffic control is the functional vitality of the railroad that ensures the integrity of train movement authorities. It does that by employing vital logic / hardware / systems that generate the movement authorities in a fashion that fails safely, i.e, unsafe authorities are not delivered. I am purposely pointing out the difference between functional vitality and logic / hardware / system vitality here in that the distinction is often overlooked, if even recognized by many railroaders. Logic / hardware / system vitality is that which signal engineers solely identify with. Too often, signal engineers mistakenly believe that signals are installed for safety purposes. Of course, signals provide for safety, but they are installed for traffic throughput in that it is possible to operate a railroad safely without signals, e.g., 50% of the trackage in the US is non-signaled traffic control. … as is ETCS level 3, … as is the most primitive token block system. Signal engineers don’t identify with functional vitality, a point which is quickly proven by asking ANY signal who has not taken my Railroad Immersion Course (brochure is available on the blog), “What’s vital in non-signaled (dark) operations?” Their response will always be “Nothing!” since there is no hardware installed along the wayside. They are so, so wrong from a functional standpoint. Vital functionality is what a railroad requires, and the vital logic / hardware of signaling systems is only one way to achieve that. (Further discussion on this point, as well as the answer as to what is vital in dark territory, is provided in a previous posting on this blog in the Teddy Bears category: There’s Nothing Vital in Dark Territory).
Arguably, the most disturbing issue currently about traffic control is the willingness by too many railroads to blindly accept both the traditional and advanced traffic control systems that are offered to them by traditional suppliers pushing what they have, versus what those railroads really require. I am not referring to high speed, high capacity operations as in Europe’s passenger operations where interoperability and traffic density are the driving factors. Rather, I am referring to all of those railroads across the other 90% of the globe that are struggling to develop a core transportation infrastructure to expand their country’s economy. How dare traditional signaling companies and consulting firms provide only products that feed the seller’s bottom line instead of pragmatic cost-effective solutions that service a railroad’s bottom line. These suppliers are providing, as well as the consultants are promoting, products instead of true solutions. (Again, I refer you to another posting on this blog: In the Light of Dark in the Railroad Business category.)
Unlike traffic control which is meant to prevent dispatching errors, enforcement is meant to prevent train crew errors. Simply stated, enforcement systems monitor the status of a train’s movement relative to its authorites. Should the system determine that the train is in jeopardy of violating an authority as to some combination of speed, distance, and time, then the enforcement system takes some combination of actions such as warnings to the crew, slowing the train, or bringing the train to a complete stop. As such, enforcement functionality can be integrated with advanced traffic control systems such as ETCS in Europe, or it can provided as an overlay system, as is the case with PTC in North America. In any event, enforcement systems are not vital as to functionality or logic / hardware (as discussed above) in that they do not generate authorities. Should, the enforcement system fail in some fashion, then the train is no less safe than it was without the enforcement system . . . Well! Almost always. One possible exception is that of an improperly designed enforcement system that makes an emergency brake application that for some reason results in a derailment.
Various types of enforcement systems have been in use in passenger operations for decades. However, for freight operations across most of the globe, enforcement systems have been extremely limited in their deployment and functionality compared to what is now available with PTC and the European flavor of Automatic Train Protection (ATP) as well as enforcement functionality incorporated in ETCS for Europe’s High Speed Passenger operations. What is unique about PTC relative to ATP / ETCS, is that no significant additional wayside infrastructure (other than a commercial or private wireless data network) is required for a very basic approach in signaled territory, with only switch monitors required in non-signaled operations. NOTE: For the hardcore PTC followers who feel tempted to correct me regarding WIU’s being required in signaled territory, I request that you first think about why WIU’s are needed if interim signals are not enforced.
Neither traffic control nor enforcement is traffic management. Traffic management deals with the efficient generation of authorities, but not the generation itself. It is designed to meet the operating directives (business value) of the railroad in managing the key resources, and as such has nothing to do with the safety of the railroad. Until recently, traffic management has been dependent upon the analytical and the rationalization of a railroad’s management team as to what was most important, i.e, moving high priority trains regardless of the cost associated with other traffic. It has only been within the last decade that advanced traffic management has introduced the mathematical tools that can displace the limited human-mentality of dispatchers to deal with the most simplistic prioritization of track time only, yet alone consider fuel utilization, crew availability, balance of locomotive distribution, and the constraints of track maintenance. I should point out that I am referring primarily to non-scheduled operations that are prevalent in North America. I am not referring to high speed passenger operations that are highly scheduled. (One more time, I offer two other postings on this blog relative to traffic management, both from the Teddy Bear category: 1) CAD Delivers Traffic Management, and 2) Train Dispatching is too Difficult for that Math Stuff.
Until a year ago, my professional railroading career as Class I management and an independent consultant had been almost totally dedicated to the freight industry of North America. There have been some interesting consulting engagements outside of that sphere, including a most peculiar investigation (I never knew who the true client was) into the traffic control and communication systems for railroads in the Middle East and Southeast Asia 25 years ago. But I was taken by surprise, actually shocked, when I read about the initiation of a study in that same corner of the world that would evaluate the safety and efficiency of a local railroad operation. It seems I didn’t really know what I thought I knew.
Having been nurtured for 36 years in the U.S. railroads, I had come to understand that operating a railroad safely requires disciplined allegiance to 1) safety systems, 2) maintenance practices, and 3) personal accountability. And, slack in any one of these three areas could readily result in the safety of a railroad’s operations being severely compromised. Hence, it was with the greatest dismay that I soon realized upon starting the study for the troubled railroad (hereon referred to as TRR), that it was suffering in all three areas as well as a fourth issue – the theft of critical wayside infrastructure. Given these significant problems, there have been a number of deadly train accidents across TRR, and there will continue to be unless all four areas are addressed properly. Thus, the focus of the TRR study was clearly directed to be that of safety first, and then efficiency.
The slap-across-the-face revelation for me was that TRR is NOT unique. Its dangerous railroading practices and problems are common in many parts of the world. Given the importance of railroads to emerging economies as providers of labor mobility and accelerators of industrialization – these safety and operating issues have far-reaching impacts. Thus, I have shifted the emphasis of my consulting to now focus on what railroads can do to address these 4 critical areas. In this post, I provide a brief description of each problem area as observed from my experience with TRR. Some readers will likely see similarities to their own operations . . . or their clients. Additionally, as will be addressed in subsequent postings, I will identify non-traditional, cost-effective and 100% safe solutions for each of the 4 areas. These are solutions that are not being provided by traditional suppliers that focus on the high speed passenger and/or high density freight networks across the globe. The solutions have to be non-standard / non-traditional since traditional suppliers produce and price for high speed/high density lines and these solutions can in fact result in a financial disaster for small and emerging railroads while increasing the likelihood of additional risk in their operations.
There are two primary levels of safety systems to consider in the movement of trains, i.e., traffic control and enforcement. TRR’s traffic control is a mixture of traditional signaling (i.e., a railroad’s traffic lights) and an antiquated token block operation. While the condition of the signaled operation across TRR is understood to be below par, it is TRR’s token block operation that requires the greatest attention.
Token block originates back in the middle of the 19th Century in Britain, and its deployment across the globe was in step with the expansion of the British Empire. Simply explained, token block’s safety, as used across TRR, is based upon an operator for each section of track (block) handing a token, e.g., metal rod, to the train crew as an authority to proceed into the block. Upon exiting the block, the train crew hands back the token to the next operator and at some point receives a new token unique to the next block. In concept, token block is a safe system. But, in practice the manual processes involving the block operator and the crew can be, and have been, violated resulting in fatal accidents. For this and perhaps other reasons, various types of Radio Electronic Token Block (RETB) have replaced manual token block in Britain and elsewhere, including a relatively short corridor in TRR. But for the majority of TRR’s operation that is still manual token block, the integrity of that operation is subject to being compromised by human error. Fortunately, as to be addressed in a forthcoming posting, there are non-signaling traffic control systems that can replace token block. These are solutions that don’t require the extensive capital investment of traditional CTC operations or the overwhelming capital investment of ETCS as used for Europe’s high speed rail networks.
Traffic control safety is not the only issue associated with safe train movements. There is also the issue of train crew errors regardless of whether the operation is in signaled territory or token block, and it is the purpose of enforcement systems to prevent such errors. In TRR’s case, an antiquated enforcement approach, Automatic Train Protection (ATP), is deployed across much of the railroad. However, based upon my visits to date, it appears that the maintenance and theft of ATP components embedded in the track as well as the train drivers turning off the on-board controller so as to not be enforced for over-speeding, has rendered the system highly ineffective. To be addressed in a latter posting, ATP is quite similar in functionality to another enforcement system referred to as Positive Train Control (PTC) that is now mandated for implementation before 2016 across most of the trackage in the U.S. PTC doesn’t have the theft, maintenance, and driver abandonment problems of TRR’s ATP system.
As suggested above, the adequateness and reliability of TRR’s maintenance procedures for wayside infrastructure and rolling stock are dubious. For the wayside infrastructure, TRR is confronted with an aging signaling system that is anticipated to have a major overhaul in the near future. However, much of the token block operation incorporates mechanical interlockings that, as with the token block equipment itself, are reportedly not up to grade. Such lack of maintenance is likely the result of two key issues. First, there is no regulatory process for providing mandatory maintenance procedures. Second, it is doubtful given just the physical appearance of the railroad overall, that governmental financial support has been anywhere near sufficient, if even budgeted.
As to equipment, I reflect on a conversation I had with a TRR executive when I asked what he thought was the most unsafe part of his railroad. Without hesitation his answer was “The brakes.” I was then told that the goal of their operation at that time was to ensure that half of the cars (wagons) in a train’s consist were equipped with working brakes – with an additional challenge of ensuring that ½ of the brake-able cars were to be placed at the beginning and the end of each train so as to reduce in-train forces.
Outside of North America, Europe and the far East, many railroads are confronted with two critical parameters that affect their ability to perform proper traffic control and supporting infrastructure maintenance. First, there is the issue of an adequately-trained work force. However, that issue can be readily handled via the use of contractors. The second parameter is the topography over which the railroad operates, and the accessibility to the wayside as well as the availability of power. Again, solutions are available, but they can be quite expensive. The point here is that railroads subjected to such parameters should consider safety systems that minimize those requirements, i.e. minimize the amount of wayside infrastructure. However, traditional suppliers do not offer those types of systems to them – why would a supplier offer a system that has less equipment. A future posting will address this point.
As demonstrated by the discussion above, there is a critical lack of consistency in personal accountability across TRR in both the operations and maintenance of critical equipment. Perhaps this is due to the fact that TRR is a government-owned railroad with seemingly little incentive to address costs or revenues. Or, perhaps this is due to the lack of a regulatory body, such as the Federal Railroad Administration (FRA) in the U.S. that mandates and enforces proper procedures. Regardless of the reasons, it is clear that TRR, or any railroad, will not operate safely without a workforce totally committed to safety. To achieve that takes documented procedures, education / training, the right incentive system and discipline throughout the organization. A future posting will address these points.
While copper wire used for pole lines has been a favorite target of thieves in the U.S. over the years, the theft of other critical components has been minimal. However, in many parts of the world, everything is fair game apparently. The treasure chest includes signaling equipment, power supplies, and in-track transponders used by Europe’s advanced traffic control system for high speed rail, ETCS. The key point here is that, as with maintenance issues noted above, a railroad should consider the vulnerability to operations and safety due to theft of critical components when selecting from alternative safety systems. The only viable solution is a system with less infrastructure to steal – but again, what supplier in their right mind would sell a system with less equipment. A future posting will address these points.
In addition to the 4 areas above, there are other significant considerations as to safe train movement operations including the use of train-integrity detection in token block operation, end-of-train monitoring of brake line pressure, wayside defect detectors, and on-board car detection systems, e.g., fire detection and alarm systems for passenger operations.
Indeed, there are overwhelming issues with the safety of TRR’s operations. The study that is being performed by my colleagues and I, will address those issues as well as identify advanced traffic management concepts that will support TRR’s increasing requirement to mix freight with passenger service on critical corridors. I know now that there are many railroads across the globe that could benefit greatly, both as to safety and financial viability, by having such a study performed without prejudice to particular approaches, equipment, or suppliers. Such a study would take into consideration safety systems, maintenance practices, personal accountability, and theft, as well as the peripheral safety considerations mentioned above.
Your correspondence is most welcomed and encouraged.
In the previous posting to this blog, In the Light of Dark, I introduced the concept of non-signaled operations used in the Americas that is most frequently referred to as Dark Territory (DT). In fact, there are two basic types of DT, i.e., Dark/Dark and Dark/Lighted (my terminology and not Googable). In Dark/Dark operations, neither the dispatcher is presented with any indication of where the train is (as in signaled CTC operations), nor is the train crew provided with any in-cab or wayside signals to present the crews with the indication of the time & speed parameters of the current movement authority (a.k.a. aspects). Instead, the crew obtains the movement authority via voice radio or as data via data radio (a.k.a. digital authorities) from the dispatcher. That is, both the dispatcher and the train crew are in the dark, so to speak, as to the train position and authority, respectively. Contrarily, in Dark/Lighted operation, the dispatcher is still unable to see the position of the train, but signals are used within the corridor to keep trains separated by block. This use of Absolute Block System (ABS) increases the possible capacity of the DT operation by adding a second level of vitality (i.e., the generation of movement authorities) to the primary authority so as to place multiple trains into a sequential set of blocks instead of having one train hold all blocks exclusively until it releases the whole set of blocks. Although a signal engineer will declare ABS to be signaled operations, it is actually DT in that the primary authority to get the train into the corridor was so generated. Regardless of the type of DT, two critical points remain true: 1. the dispatcher doesn’t know where the train(s) is in the DT corridor, and 2. the dispatcher doesn’t know the speed of the train(s). But, that’s OK, seemingly, because DT is used for low to medium density operations … or is it really OK? Actually, it is no longer OK.
Traditional railroaders have accepted that DT has limited capacity due to the manual efforts of transmitting authorities and subsequently releasing them. But, what if a railroad was to obtain the actual position and speed of trains, and then use mathematical movement planners to adjust the generation of movement authorities in a more dynamic fashion? That is, what if a dispatcher had a Planning Platform, either integrated or independent of CAD, that could more efficiently plan the generation of authorities, and then have the dispatcher use CAD as the execution platform that it truly only is? That is, what if the dispatcher had what I have introduced 5 years ago as Proactive Traffic Management (PTM) instead of the reactive, crisis-based management of train movements (more on this in a future posting)?
Now, the question is: How much capacity can be obtained with DT operations that use the dynamic duo of digital authorities and PTM, whether dark/dark or dark/lighted? Of course, the answer varies for each individual corridor. But no railroad, to my knowledge, has attempted to answer that question. They don’t know what they don’t know. Instead, they take the traditional signaling approach that requires heavy investment in infrastructure as well as extensive maintenance costs to ensure the reliability of the equipment. Additionally, such signaling operations in developing countries are subject to theft and deterioration due to poor maintenance given a lack of adequately train maintenance personnel.
The great news is that such capacity evaluations can be performed through the use of mathematical models not unlike those that are used to calculate the theoretical throughput of signaled operations. But again, to my knowledge, no one is using such models. Clearly, neither suppliers nor traditional consultants that advise railroads are doing such analyses in that they will not sell anything since 1. there is no infrastructure investment for DT other than wireless data, and 2. they don’t have operational experience with such operations, respectively. That’s where my associates and I can be brought into play.
As my team of professional railroaders and planners are pursuing with small and emerging operations in selected areas of the globe, there is the opportunity to bring those types of alternatives to railway management. The icing on the cake is that we also can advise on the use of enforcement systems, such as PTC, so as to provide for as safe of a railroad operation that is possible with both reliable traffic control and efficient traffic management, as well as assure that a train crew will not violate their authorities. It doesn’t get any better than that.
If what I have discussed above applies to your railway, then we need to talk. By the way, my team doesn’t represent any suppliers, nor do we accept commissions from suppliers. We work for your railway’s best financial and operational interests.
Rail professionals, whether from the railroads or the suppliers, associated with North American freight rail or European/Asian high speed passenger live and breathe some form of fixed block, signaled operation, either wayside or in-cab, as the means to provide crews with reliable movement authorities to advance trains. However, of that group only a relatively small percentage is operationally-familiar with the well-established, non-signaled operation (a.k.a. Dark Territory [DT]) that is used across 50% of U.S. rail trackage (albeit handling only 20% of the traffic).
What causes this lack of awareness? Essentially, traditional traffic control suppliers have nothing to sell in DT – there is no infrastructure required other than wireless – hence no business interest. Additionally, the heretofore, manual-only processes of DT have made it incapable of handling the requirements of high speed and/or high density operations, whether freight or passenger. I say heretofore in that the digital age has now come to DT.
The availability of a wireless data network (with or without PTC) permits the time consuming, and possibly compromised, voice transmissions of the movement authorities between the crews and the dispatcher in DT operations to be handled as data presented via an on-board display. Additionally, that same wireless data path can be used to release authorities in the back office DT platform logic, a.k.a., conflict checker. This double time-reduction whammy provides for a quantum increase in the capacity that a dispatcher can handle in DT operations.
But, outside of the Americas, the capability of DT, with or without the quantum improvement, is one of best kept secrets that, if known, could have a phenomenal effect on small and emerging railroads; railroads that are critical to the business and social welfare of their respective countries. Again, I am not talking about the sophisticated railways of Europe, but the railways that are being considered across Africa, the Middle East, India, Indonesia, and elsewhere. These railroads could see a massive increase in capacity for minimal investment in a green-field operation to a net-savings for a railroad operating on an older signaling system (removing the older system would save future operating and maintenance costs, often resulting in a net savings). In addition, a traffic control system without wayside infrastructure results in less expensive equipment to be stolen or damaged by harsh environs reducing operating costs and increasing safety.
The railroads across the globe that could benefit from DT come in two types. First, there are railroads that are emerging either as green-field developments or as rebuilds of railways that have been reduced to rumble or abandoned for civil and/or economic reasons. Second, there are those railroads that are fully functional but are dependent upon the most antiquated traffic control system generically known as Token Block (TB). With its development stemming from the middle of the 19th century in Britain, TB can be found in patches across the globe. TB is safe in concept. That is, to operate within a particular segment of track , a crew must possess a token, physical /electronic that is uniquely assigned to that segment. However, as I witnessed in my assignment in Egypt regarding the Egyptian National Railways (ENR) to evaluate safe railroading, including both traffic control and enforcement, the manual processes involved in TB ( 85% of ENR’s trackage) permit the vitality of operation to be greatly compromised. When those processes are violated; major accidents have occurred.
So! Here’s the problem. While DT is an excellent traffic control approach for small and emerging railroads, these operators are not being informed of its availability. Instead, major suppliers are selling (and traditional consultants are promoting) the major systems that have been deployed across major rail operations as the only solutions. Such solutions put these railroads at considerable financial risk , not only due to the initial investment required, but also as to the on-going profitability due to a combination of extensive maintenance and training costs, a likely lack of disciplined and educated maintenance personnel, and the susceptibility to theft of wayside infrastructure.
Hopefully, the safety project I mentioned in Egypt, as well as the marketing efforts of myself and my colleagues (we don’t represent suppliers nor accept commissions) will help spread the knowledge of Dark Territory and bring it into the light of those nationalized and private railroads that can truly benefit from its deployment.
“Operating a railroad safely requires signaling.”
Major suppliers sell major signaling systems to major railroads for major bucks. But what about those small freight railroads, even those with some passenger service? Do they really require the traffic control systems that are offered to them; the ones that involve extensive investment in wayside infrastructure, communications, and back office systems? Additionally, what about those railroads that are being planned for difficult terrain subject to extreme weather, a lack of power, theft of equipment, and a lack of trained maintenance personnel? Do they need to confront these hardships on top of extensive investment and on-going maintenance costs to provide for a safe railroad?
While signaling does provide for safe operations, that is not its purpose. Signaling is used to provide capacity. It is possible to operate a railroad very safely without signaling, as well evidenced in North America. Specifically, nearly half of the freight trackage in N.A. operates as non-signaled territory (albeit only 20% of the traffic) meaning that there are no track circuits, no wayside or cab signals, and no code lines as required in Centralized Traffic Control (CTC) systems. The only technology requirement is that of some form of wireless communications that can be either commercial (satellite, cellular) or private network sufficient to provide for voice communications. That’s it for the infrastructure.
As to the vitality (i.e., the integrity of train movement), as noted in the post “There’s nothing vital in dark territory.”, the computerized conflict checking process is the simplest of a traffic control process that doesn’t permit two trains to be in the same portion of track at the same time. In a way, this is not unlike the most ancient traffic control system based upon track occupancy referred to as token block. The key difference is that dark territory is programmed whereas token block’ vitality can be readily compromised by lack of discipline with the manual efforts required; indeed this is the case in some countries where it is still in use.
The only issue with dark territory is the time required for the iterative, manual process of the dispatcher transmitting the movement authorities to the train crew followed by the rolling-up of the authorities once the train crew has reported the train’s progress. With such a simple process, a decent size freight or passenger railroad can operate safely. Additionally, there are even ways to tweak dark territory operation to improve capacity even further, e.g., digital transmission of authorities, automatic roll-ups, embedded signals (without CTC), and the ability to throw switches from the locomotive. Lastly, with the combination of dark territory and Positive Train Crew (PTC), the railroad is assured of a safe operation both as to dispatcher errors and train crew errors respectively.
Also, Dark territory is really, really inexpensive. However, don’t expect those major suppliers or consultants to share its existence with small to medium railroads. First of all, those supplier don’t have a dark territory deliverable or mindset, and second, there is nothing for them to sell as to infrastructure and complex back office systems.
The team of railroad professionals at Maendeleo Rail is well experienced with dark territory operations as well as PTC. We can readily address the alternatives as to processes and wireless technologies, as well as determine the level of throughput that can be delivered for freight, passenger, or mixed traffic. Since we’re independent of any suppliers, and instead look to partner with railroad operators, we provide low cost, highly efficient solutions.
“There’s nothing vital in dark territory.”
My Railroad Immersion Course has been used by railroads and suppliers alike to obtain a new perspective of railroad operations based upon advancing the traditional core technologies of communications, positioning, and intelligence, i.e., wireless voice, track circuits, and Computer Aided Dispatching (CAD), respectively. When giving the course to traditional traffic control suppliers, I address the difference between signaled and non-signaled operations (a.k.a., dark territory). Consistently, there is a point in the course where it makes a transition from a one-way lecture to a very interactive discussion. Specifically, it is when I ask the question: “So! What’s vital in dark territory?” Without fail the response is “There’s nothing vital in dark territory.” And, with as much detente that my personality permits, I respond “Really?”
From their perspective there is an understandable reason why traffic control suppliers would respond as such in that dark territory operation is one in which they have little to no experience in that there is no wayside infrastructure required, and hence there is nothing for them to sell. Additionally, the term vitality to these folks has a very product-oriented perspective of failing safely, i.e., to not place the railroad in the position of additional risk upon a failure in the signaling infrastructure. Therefore, their logic would be that since there is no product along the wayside, then there is no vitality. Voila!
What traffic control suppliers don’t consider is that vitality has also a functional perspective of insuring the integrity of train movements … which more specifically means that the movement authorities are generated in a fashion that provides for safe train movements; that indeed is the underlying requirement of signaling infrastructure after all. Therefore, to answer the question of what is vital in dark territory means identifying the source of movement authority generation. This is where the discussion really takes off.
Usually the second answer offered by the class is “The dispatcher is vital.” Wrong!. Just as in signaled territory, the dispatcher does not generate the authority and therefore is not vital. He does indeed set up the authority generation process, as well as deliver the authority via voice radio. But, he does not generate the authority. In the old days, authority generation in non-signaled territory was provided by the train sheet, which is literally a piece of paper, upon which the dispatcher managed the allocation of track distance and time. The dispatcher abided by what the train sheet permitted him to do or not do as to the allocation of track. Today, the movement authority generation is a computerized program, a.k.a., conflict checker, that emulates the train sheet. The underlying logic of either the track sheet or the conflict checker cannot be simpler. That is, a specific portion of track can only be allocated to one train at a time. That’s it (with some exceptions that are not important here). That’s vitality in dark territory. Should the dispatcher wish to override this vitality in some fashion, then s/he has now become vital. But wait, there’s more.
Once everyone is satisfied with that understanding, I move onto Automatic Block operation (ABS) which is the use of signals within dark territory operation, what I refer to as dark / lighted operation. In ABS, the signals function the same as they do in CTC territory, but the dispatcher is not provided with the aspects. Hence, it is dark to the dispatcher, but lighted to the train crew. Now the question to the class is two-fold. First, “Is ABS signaled operation or dark operation?” Second, “What is vital in ABS operation?” Those individuals who have been following the discussion up to that point usually respond quite well to these two questions. However, for hardcore signal engineers it is difficult to realize that the overall operation is dark (officially so) in that the initial movement authority to get the train into ABS was provided by the conflict checker. However, once in ABS, the train is subjected to a second level of authority from the signal infrastructure. Hence, there are two levels of vitality. But wait, there’s more.
Once everyone is satisfied as to ABS, I now introduce the concept of work zones where maintenance crews have the authority for a portion of track for a given period of time. The question to the class then is “What’s vital in a work zone?” Hopefully, by now they are able to respond that the Employee in Charge (EIC) of the work zone adds an additional level of authority to the train that has the movement authority generated by the traffic control system to move through the area. That is, the train crew must request permission by the EIC to enter the work zone when that zone is in effect. Hence, the EIC is vital within the work zone. But wait, there’s more.
After this discussion, the class is now thinking about vitality from a functional standpoint. This leads to two more questions for their consideration … and which leads to forthcoming Teddy Bear Posts regarding the vitality of PTC and the vitality of transmitting authorities in non-signaled operations. By the way,check out a brochure for the Railroad Immersion Course.