Brighton Park crossing
Brighton Park crossing is a major railroad crossing in Chicago, Illinois, hosting three of the major Chicago freight railroads. The crossing is northwest of the intersection of Western Avenue and Archer Avenue, in the Brighton Park neighborhood of Chicago, Illinois. The railroads involved in the crossing are CSX, Canadian National and Norfolk Southern. The crossing consisted of the CN's two-track line in a roughly east/west orientation, crossing the five north/south tracks operated by NS and CSX. Collectively, these railroads operate approximately 80 trains per day through the crossing. The CN line was formerly the main line of the Gulf Mobile & Ohio and its predecessor Alton Railroad and currently carries Metra Heritage Corridor commuter trains and Amtrak passenger trains to St. Louis. The GM&O's Brighton Park passenger stop was at this location. The junction may be easily viewed from the CTA Orange Line trains that pass on an elevated structure immediately southeast of the crossing.
Until July 6, 2007, the crossing was controlled by a human switchtender in a cabin near the crossing using semaphore signals to govern train movements through the diamonds. Because the crossing was not interlocked, all trains were required to make a stop before proceeding over the crossing as signaled by the specific semaphore signal governing the track the train was on. As a major crossing, and one of the few remaining locations with this classic method of operation, Brighton Park was a major attraction for rail enthusiasts, but had become increasingly inefficient for Chicago area rail operations.
As part of the Chicago Region Environmental and Transportation Efficiency Program (CREATE) project, the Brighton Park crossing, the semaphore signals, and switchtender's cabin were taken out of service on the evening of Friday, July 6, 2007 and conversion to an interlocked crossing ensued over the following weekend. As part of the conversion project, some of the tracks at the crossing were realigned and new crossing diamonds were put in place.
By the early 20th century Brighton Park crossing involved tracks belonging to the Baltimore and Ohio Chicago Terminal, the Chicago Junction Railroad (eventually controlled by the New York Central as the Chicago River and Indiana) and the Pittsburgh, Cincinnati, Chicago and St. Louis Railroad commonly known as the "Panhandle Route", which was controlled by the Pennsylvania Railroad (PRR) running north to south and crossing the Chicago and Alton main line running east to west. The PCC&StL was the first railroad to cross the C&A at Brighton Park in the 1860s and therefore was responsible for arranging the safe crossing of trains. As other railroads built along the Panhandle right of way, this arrangement remained in effect with the responsibility passing to the PRR.
For the PRR the Panhandle Route connecting Pittsburgh and Cincinnati via Indianapolis was of secondary importance to its Main Line via Fort Wayne, IN, with the latter having direct access to Chicago Union Station from the south, while the Panhandle route ran west of the city to loop around and access the station from the north. The Baltimore and Ohio was somewhat late arriving into the Chicago market and had to use trackage rights and the Panhandle right of way to eventually reach Grand Central Station via a similar out and back loop route and arrived south of downtown via the St. Charles Air Line. The Chicago Junction Railroad was a switching and terminal railroad that served the stockyard area and was eventually purchased by the New York Central.
At its peak the crossing involved a total of 8 tracks of the PRR, B&OCT and CR&I crossing the two tracks of the C&A. Also included in the complex were a number of hand operated crossovers and wye tracks. Each of the 4 railroads involved in the crossing employed switchtenders on site to manage any crossover or connecting movements, with the PRR maintaining two tender stations, north and south of the crossing, to protect the two B&OCT to C&A wye tracks where they each crossed the Panhandle main line and the C&A crossing itself. Switchtender cabin "A" managed the Alton crossing and would continue to do so until the crossing was interlocked in 2007.
For both the B&OCT and PCC&StL Brighton Park was one in a string of non-interlocked railroad crossings at grade with others at Ash Street, 26th St and 12th St. Maximum speed on the route was between 20-30 mph. Interlocking the Brighton Park crossing would have been of limited value without upgrading the entire line. As passenger traffic on the route dried up and the railroads entered financial hardship, investment in the line became less and less of a priority. With the formation of the Penn Central and later Conrail, the PCC&StL and CR&I lines through Brighton Park were united under a single railroad. The Panhandle route was ultimately abandoned with Conrail shifting traffic to the C&RI, ripping up the two Panhandle tracks, thus reducing the number of tracks crossing the Alton to 5. Under Conrail the CR&I was designated as an industrial track, its lowest classification. Since the PRR era crossing agreement with the Alton successor Illinois Central Railroad was still in effect, Conrail had little incentive to upgrade the signaling on the line.
In terms of physical freight and passenger rail loading, Brighton Park carries a heavy amount of traffic, approximately 3.5 trains every hour (as of the year 2009.) The amount of traffic might be expected to increase over time as more and more cargo is transported via rail instead of via highway trucking and inter-coastal waterways as the cost of fuel increases and as the efficiency of locomotive engines increase.
The modernization effort to automate the Brighton Park crossing involved Safetran Systems, (part of Invensys Rail) with the crossing’s application development, site mock-up, and preliminary factory testing taking place in Rancho Cucamonga, California in an in-house project called “Brighton Park / Pershing Main.”
There were five different aspects of the modernization effort which consisted of (1) track circuits, signals and other wayside appliances, (2) vital interlocking software and hardware systems, (3) non-vital communications systems, (4) event data recording, and (5) input/output, all of which could be controlled and monitored by remote dispatch operators using display and control panels.
The project’s hardware and software consisted of existing Safetran components however the various application logic and site configuration modules were developed specifically for Brighton Park, all of which was heavily tested in California via a system-wide mock-up, requiring approximately 45 developers consisting of systems engineers, hardware and software engineers, applications engineers, test technicians, technical technicians, technical publishers, and others.
The new microprocessor based interlocking logic also supports various types of positive train control and other advanced signaling technologies which may come in to play to support the proposed 110 mph service on the Lincoln Corridor.
Interlocking and control hardware
For the vital aspects of the interlocking, the Geographic Signal System (GEO) device was applied. Non-vital communications between GEO devices included Wayside Access Gateways (WAG) and Ethernet Spread Spectrum Radios (ESSR.) Some logic control as well as event data recording is supplied by the Safetran Event Analyzer Recorder (SEAR2.) A number of different I/O devices are used, including Unipolar I/O (UIO.) A large model board for local control of the interlocking plant was also fabricated.
The use of wireless data communications allows a large number of distributed field hardware to be linked together without the need for failure prone physical cable links. The system is fail safe in case of loss of link or data packet corruption and any individual part of the interlocking plant will automatically ensure that the least permissive action is taken in the case of absent or inconsistent data from one of its sources.
Software subsystems and communications protocols
GEO devices, Unipolar I/O, and SEAR2s collect information about the crossing and surrounding region, either by monitoring voltages on wires or by passing messages among themselves. Logic software massages the real-world information and decides what signal aspects to show locomotives and decides what information to indicate to crossing predictors which assist the predictors in determining whether crossing gate arms should be lowered or raised, lights flashed, and bells rung.
Though the communications infrastructure (consisting of WAGs, radios, Ethernet bridges and such) are non-vital, messages conveying vital information is passed between vital devices using the communications infrastructure, messages which are encapsulated in Advanced Train Control System[better source needed] (ATCS) messages and carry 32-bit Cyclic Redundancy Check[better source needed] (CRC) values which are used to verify with extreme accuracy that messages have not been corrupted.
Vital messages also carry timestamps and sequence information such that in the event of unexpected routing delays or routing loops, obsolete messages will be ignored and duplicate messages will be eliminated.
Vital systems establish communications sessions among themselves which are constantly maintained so that in the event of interference (incidental or deliberate) sessions will drop and the crossing will go to the least permissive state.
The vital systems communicate among each other via twisted-pair LAN called Echelon which operate at around 1.2 megabit per second. The WAGs take the Echelon-encoded ATCS messages and may route them out their 10-megabit Ethernet interface, causing the messages to be transmitted to other WAGs via spread spectrum radios where they are converted back into Echelon messages.
While rail traffic through Brighton Park is heavy, the communications traffic among the vital systems providing the automation is also quite heavy. Vital session ATCS messages conveyed between GEO devices constitute hundreds of messages every second. Overlaid on the vital sessioning is additional message traffic for monitoring, remote log retrieval, command and control, and other types of messages, all of which must be created, transmitted, received, and handled quickly so that messages are not permitted to become stale.
In the Safetran Systems California manufacturing facility, a full-scale mock-up of the Brighton Park / Pershing Main project was assembled with moving locomotives being simulated using Safetran GEO Test Terminal devices and physical interlocking appliances with panel lamps.
The modernization effort at Brighton Park took place in parallel with the mock-up effort in California, allowing application development and extensive testing to take place on the mock-up prior to the application being cut-over in Chicago. Most installation issues which developed during cross-over could be replicated and solved in California, with the only real exception being radio communications coverage between devices along the rail line.
The automation hardware and software was launched and monitored for a trial period of time during which the existing physical semaphoring system was still in use until confidence in the automation effort was achieved after which the wonderful (but obsolete) signaling system was finally discontinued.
Once the initial site installation difficulties were isolated and resolved, the new interlocking system settled down and has been conveying indications and controls without difficulties.
- Gustason, Bill (2006). "Brighton Park Crossing". Chicago Area Rail Junctions. Retrieved 2006-07-20.
- "Safetran Geographic Signal System".
- "Safetran Wayside Access Gateway" (PDF).
- "Safetran Ethernet Spread Spectrum Radio" (PDF).
- "Safetran Event Analyzer Recorder 2" (PDF).
- "Safetran Unipolar I/O" (PDF).
- "Advanced Train Control System Specification".
- "Cyclic Redundancy Check".
- "Echelon LonTalk".
- Chicago Rail Junctions: Brighton Park
- CREATE Project
- Photos of trains passing Brighton Park Junction at Railpictures.Net