Controlling System Costs: Basic and Advanced Scheduling Manuals and Contemporary Issues in Transit Scheduling (2009) / Chapter Skim
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Pages 354-380
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From page 354... ...
Chapter 7. Rail Scheduling ͳ.ͭ Rail Scheduling
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From page 355... ...
High platform rapid transit lines, often referred to as "Heavy Rail," use a diff erent approach from light rail or surface streetcar lines. Commuter rail is diff erent altogether.
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From page 356... ...
Most common on frequent rail lines where close headways do not allow suffi cient layover time for the train crew, this technique is also used for special events to maximize the number of trains in service. If service is very frequent, the train crew may not board the next train but instead the train after that; this is called a "double drop-back." Some agencies use the term "fall-back" instead.
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From page 357... ...
On sections operating in mixed traffi c, running times are set using the same procedures described earlier for bus routes, and may change throughout the day. Longer-length rail lines will often have yards on both ends of the line in order to cut down on the amount of time and mileage for nonessential trips that just serve to get out of or into the yard.
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From page 358... ...
As mentioned above, practical operation and signal systems rarely allow for trains to be closer than two minutes apart. On most heavy rail lines and light rail lines that run on private right-of-way, this rule is enforced by cab signal systems, which will automatically brake the train if one gets too close to the one ahead.
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and east (Soto Station) sides of the line as shown in the Route ͭͬͬ Light Rail Track Diagram below.
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Sample roundtrips are shown below, confi rming that the layover times work as expected and that six blocks are needed. cycle time Sum of the round trip running time plus layover time.
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HE A D W A Y S HE E T L ine 100 - L igh t Ra i l IN EFF : Fa ll 2008 M ONDAY THRU FR IDAY D IR E C TIO N = E A S T-W E S T A B C D E F G G F E D C B A WEST DEKALB LORAIN DNTWN MIDDLE SOTO EAST EAST SOTO MIDDLE DNTWN LORAIN DEKALB WEST BLOCK TERM STA STA TERM BURG STA TERM LVE.
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From page 362... ...
This is more than enough so that drop-backs do not need to be considered. Sample long trips for the peak are: HE A D W A Y S HE E T L ine 100 - L igh t Ra i l IN EFF : Fa ll 2008 M ONDAY THRU FR IDAY D IR E C TIO N = E A S T-W E S T A B C D E F G G F E D C B A WEST DEKALB LORAIN DNTWN MIDDLE SOTO EAST EAST SOTO MIDDLE DNTWN LORAIN DEKALB WEST BLOCK TERM STA STA TERM BURG STA TERM LVE.
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From page 363... ...
HE A D W A Y S HE E T L ine 100 - L igh t Ra i l IN EFF : Fa ll 2008 M ONDAY THRU FR IDAY D IR E C TIO N = E A S T-W E S T A B C D E F G G F E D C B A WEST DEKALB LORAIN DNTWN MIDDLE SOTO EAST EAST SOTO MIDDLE DNTWN LORAIN DEKALB WEST BLOCK TERM STA STA TERM BURG STA TERM LVE.
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From page 364... ...
A 6:55 7:28 7:32 1 6:00 6:09 6:42 6:50 7:00 1 7:00 7:08 7:41 7:50 8:00 A 6:17 6:50 6:55 B 7:10 7:43 7:47 2 6:15 6:24 6:57 7:05 7:15 2 7:15 7:23 7:56 8:05 8:15 B 6:32 7:05 7:10 C 7:25 7:58 8:02 3 6:30 6:39 7:12 7:20 7:30 3 7:30 7:38 8:11 8:20 8:30 C 6:47 7:20 7:25 D 7:40 8:13 8:17 HE A D W A Y S HE E T L ine 100 - L igh t Ra i l IN EFF : Fa ll 2008 M ONDAY THRU FR IDAY D IR E C TIO N = E A S T-W E S T A B C D E F G G F E D C B A WEST DEKALB LORAIN DNTWN MIDDLE SOTO EAST EAST SOTO MIDDLE DNTWN LORAIN DEKALB WEST BLOCK TERM STA STA TERM BURG STA TERM LVE.
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The reason for this is the short trips, which do not line up across the page as their cycle is two trains shorter. Keep in mind that you have variable running time on this schedule.
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This is where a thorough knowledge of the light rail system and its operation is vital. In the example, we have allowed ͭͬ minutes, which our operating personnel have told us is suffi cient.
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HEADWAY SHEET Line 100 - Light Rail IN EFF: Fall 2008 MONDAY THRU FRIDAY DIRECTION = EAST-WEST A B C D E F G G F E D C B A OUT WEST DEKALB LORAIN DNTWN MIDDLE SOTO EAST IN OUT EAST SOTO MIDDLE DNTWN LORAIN DEKALB WEST IN BLOCK YARD TERM STA STA TERM BURG STA TERM YARD LVE.
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We put the all day blocks in order at the start of the base period (they don't stay in order because of the shorter cycle of the short trips) , then number the four AM blocks above these, then the four PM blocks.
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V E H . TR A IN TIM E TIM E H O UR S M ILE S 1 4 :45 1 :02 20 :17 2 6 :21 19 :22 13 :01 3 5 :00 23 :17 18 :17 4 5 :58 19 :37 13 :39 5 4 :20 23 :47 19 :27 6 5 :50 19 :34 13 :44 7 4 :50 0 :56 20 :06 8 6 :06 19 :49 13 :43 9 5 :05 23 :11 18 :06 10 5 :35 23 :41 18 :06 11 5 :30 9 :53 4 :23 12 5 :43 9 :40 3 :57 13 4 :15 9 :30 5 :15 14 6 :13 9 :38 3 :25 15 15 :12 24 :26 9 :14 16 15 :13 19 :07 3 :54 17 15 :20 24 :42 9 :22 18 15 :21 19 :22 4 :01 TO TA L 211 :57 TRAIN BLOCK SUMMARY As an example, if we needed one more pull-in to the West Yard, we might consider taking block ͯ, scheduled on a short pull-in trip leaving East Terminal at ͭͭ:ͬͱ PM (highlighted below in gray)
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From page 373... ...
One reason for constructing light rail lines is their large passenger carrying capacity. A standard articulated light rail car which is ͵ͬ-͵ͱ feet in length can seat ͳͬ per car and carry another Ͳͬ standees comfortably.
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The policy of the particular light rail system may be to use yard crews. If so, many systems schedule these crews as Miscellaneous Runs.
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. Here are some diff erences in heavy rail scheduling: Running times would vary only slightly throughout the day.
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If the terminal is built along the lines of Diagram ͯ, use of crossover B is preferred, provided that the increment of length/running time it adds does not require an additional consist and/ or crew in the cycle. This provides customers the fastest ride from the prior station into the terminal with little, if any, delay.
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From page 378... ...
When the train does arrive, the drop-back crew will board at the rear of the train, "ride" into the "pocket" and reverse the train's direction with the original crew alighting when the train gets back into the platform. Use of loop C, again if it does not require an additional consist and/or crew in the cycle, is operationally superior but more costly in terms of accumulated car miles.
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From page 379... ...
can be used in peak periods on the tail tracks as well as off -peak storage of out of service cars/consists, minimizing car-miles. Knowledge of the impact of these designs on scheduling is imperative.
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