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Chapter 4. Schedule Blocking Level . Advanced Blocking 4.4 Advanced Blocking The advanced section of the Schedule Building chapter made running time chang- LEVEL es and added a trip to Route to reduce overcrowding. Both changes occurred 3 in the PM peak. The first steps in this section are to make sure that every trip hooks properly and then begin the process of reblocking, starting at the beginning of the PM pull-outs. It is a good practice to carry each block through to the end of the schedule as it is easy to get confused between the old blocks and the new. In this example, there is enough of a change where no block finishes its day the same as it did in the original schedule. The final schedule is shown below, with the existing blocks from the intermediate section for all trips through the beginning of the PM peak. The blocking for Part of the schedule is un- changed, because running time and headway remain the same in the AM peak and the midday period. The remainder of this section focuses on Part of the Route schedule. Recall from the advanced section of Chapter : Schedule Building that you can expect two new PM-only blocks as a result of these changes. So you expect to end up with Block , as op- posed to Block at the end of the blocking exercise in the intermediate section. 4-68

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Level . Advanced Blocking Chapter 4. Schedule Blocking S C H E D U L E S H E E T w ith ad jus te d running tim e and he ad w ays R o u te 96 IN EF F : M O N D A Y T H R U F R ID A Y P art 1 N O R TH B O U N D S O U TH B O U N D OUT Libby Sand Pasco Pasco Pasco Rugby Rugby Pasco Pasco Pasco Sand Libby NEXT IN BLK GAR Wishrm Point Essex Havre Willis Circle Circle Willis Havre Essex Point Wishrm TRIP BLK GAR 9602 4:10 4:20 4:28 4:35 4:43 4:53 5:05 9602 9601 3:45 4:05 4:18 4:26 4:33 4:41 4:50 4:58 5:05 5:13 5:23 5:35 9601 9605 4:55 5:05 5:13 5:20 5:28 5:37 5:49 9605 9603 4:15 4:35 4:48 4:56 5:03 5:11 5:20 5:29 5:37 5:47 5:57 6:05 9603 9604 4:39 4:59 5:08 5:16 5:23 5:31 5:35 5:44 5:52 6:02 6:12 6:19 9604 9602 5:05 5:19 5:29 5:37 5:46 5:50 5:59 6:07 6:17 6:27 6:45 9602 9605 4:59 5:19 5:29 5:39 5:47 5:56 6:05 6:14 6:22 6:32 6:42 6:57 9605 9601 5:35 5:49 5:59 6:07 6:16 6:20 6:29 6:37 6:47 6:57 7:05 9601 9605 5:49 5:59 6:09 6:17 6:26 6:35 6:44 6:52 7:02 7:12 7:17 9605 9603 6:05 6:19 6:29 6:37 6:46 6:50 7:01 7:10 7:21 7:32 7:45 9603 9604 6:19 6:29 6:39 6:47 6:56 7:05 7:16 7:25 7:36 7:46 7:57 9604 9607 6:05 6:25 6:39 6:50 6:59 7:10 7:15 7:26 7:35 7:46 7:57 8:05 9607 9608 6:17 6:37 6:49 7:00 7:09 7:20 7:25 7:36 7:45 7:56 8:06 8:23 9608 9602 6:45 6:59 7:10 7:19 7:30 7:35 7:46 7:55 8:06 8:17 8:35 9602 9606 6:57 7:09 7:20 7:29 7:40 7:45 7:56 8:05 8:16 8:26 9606 8:46 9601 7:05 7:19 7:30 7:39 7:50 7:55 8:06 8:15 8:26 8:37 9601 8:57 9605 7:17 7:29 7:40 7:49 8:00 8:05 8:16 8:25 8:36 8:46 8:53 9605 9609 7:05 7:25 7:39 7:50 7:59 8:10 8:15 8:26 8:35 8:46 8:57 9:05 9609 9610 7:17 7:37 7:49 8:00 8:09 8:20 8:25 8:36 8:45 8:56 9:06 9:23 9610 9603 7:45 7:59 8:10 8:19 8:30 8:35 8:46 8:55 9:06 9:17 9:35 9603 9604 7:57 8:09 8:20 8:29 8:40 8:45 8:56 9:05 9:16 9:26 9604 9:46 9607 8:05 8:19 8:30 8:39 8:50 8:55 9:06 9:15 9:26 9:37 9607 9:57 9608 8:23 8:34 8:44 8:52 9:02 9:07 9:18 9:27 9:38 9:48 9:53 9608 9602 8:35 8:48 8:58 9:06 9:16 9:22 9:32 9:40 9:50 10:01 10:05 9602 9605 8:53 9:04 9:14 9:21 9:31 9:37 9:46 9:53 10:03 10:13 10:23 9605 9609 9:05 9:18 9:28 9:35 9:44 9:52 10:01 10:08 10:18 10:29 10:35 9609 9610 9:23 9:33 9:43 9:50 9:59 10:07 10:16 10:23 10:33 10:43 10:53 9610 9603 9:35 9:48 9:58 10:05 10:14 10:22 10:31 10:38 10:48 10:59 11:05 9603 9608 9:53 10:03 10:13 10:20 10:29 10:37 10:46 10:53 11:03 11:13 11:23 9608 9602 10:05 10:18 10:28 10:35 10:44 10:52 11:01 11:08 11:18 11:29 11:35 9602 9605 10:23 10:33 10:43 10:50 10:59 11:07 11:16 11:23 11:33 11:43 11:53 9605 9609 10:35 10:48 10:58 11:05 11:14 11:22 11:31 11:38 11:48 11:59 12:05 9609 9610 10:53 11:03 11:13 11:20 11:29 11:37 11:46 11:53 12:03 12:13 12:23 9610 9603 11:05 11:18 11:28 11:35 11:44 11:52 12:01 12:08 12:18 12:29 12:35 9603 9608 11:23 11:33 11:43 11:50 11:59 12:07 12:16 12:23 12:33 12:43 12:53 9608 9602 11:35 11:48 11:58 12:05 12:14 12:22 12:31 12:38 12:48 12:59 13:05 9602 9605 11:53 12:03 12:13 12:20 12:29 12:37 12:46 12:53 13:03 13:13 13:23 9605 9609 12:05 12:18 12:28 12:35 12:44 12:52 13:01 13:08 13:18 13:29 13:35 9609 9610 12:23 12:33 12:43 12:50 12:59 13:07 13:16 13:23 13:33 13:43 13:53 9610 9603 12:35 12:48 12:58 13:05 13:14 13:22 13:31 13:38 13:48 13:59 14:05 9603 9608 12:53 13:03 13:13 13:20 13:29 13:35 13:45 13:52 14:03 14:14 14:23 9608 9602 13:05 13:18 13:28 13:35 13:44 13:50 14:00 14:07 14:18 14:30 14:35 9602 9605 13:23 13:33 13:43 13:50 13:59 14:05 14:15 14:22 14:33 14:44 14:53 9605 9609 13:35 13:48 13:59 14:06 14:16 14:20 14:30 14:37 14:48 15:00 15:05 9609 4-69

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Chapter 4. Schedule Blocking Level . Advanced Blocking S C H E D U L E S H E E T w ith ad jus te d running tim e and he ad w ays R o u te 96 IN EF F : M O N D A Y T H R U F R ID A Y P art 2 N O R TH B O U N D S O U TH B O U N D OUT Libby Sand Pasco Pasco Pasco Rugby Rugby Pasco Pasco Pasco Sand Libby NEXT IN BLK GAR Wishrm Point Essex Havre Willis Circle Circle Willis Havre Essex Point Wishrm TRIP BLK GAR 9610 13:53 14:03 14:14 14:21 14:31 14:35 14:45 14:52 15:03 15:14 15:23 9610 9603 14:05 14:18 14:29 14:36 14:46 14:50 15:00 15:07 15:18 15:30 15:35 9603 9608 14:23 14:33 14:44 14:51 15:01 15:05 15:15 15:22 15:33 15:44 15:58 9608 9602 14:35 14:48 14:59 15:06 15:16 15:20 15:30 15:37 15:48 16:00 16:05 9602 9611 15:23 15:33 15:44 15:52 16:03 16:15 16:23 9611 9605 14:53 15:03 15:14 15:21 15:31 15:45 15:56 16:04 16:15 16:28 16:30 9605 9609 15:05 15:18 15:29 15:36 15:46 15:57 16:08 16:16 16:27 16:39 16:41 9609 9610 15:23 15:33 15:44 15:51 16:01 16:09 16:20 16:28 16:39 16:52 16:55 9610 9603 15:35 15:48 15:59 16:06 16:16 16:20 16:32 16:41 16:53 17:05 17:08 9603 16:19 16:29 16:41 16:50 17:02 17:15 17:17 9612 15:43 15:58 16:09 16:16 16:26 16:37 16:49 16:58 17:10 17:22 17:17 9612 9608 15:58 16:08 16:19 16:26 16:36 16:45 16:57 17:06 17:18 17:31 17:40 9608 9602 16:05 16:18 16:29 16:36 16:46 16:53 17:05 17:14 17:26 17:38 17:53 9602 16:11 16:26 16:38 16:46 16:57 17:01 17:13 17:22 17:34 17:47 18:07 16:23 16:34 16:46 16:54 17:05 17:09 17:21 17:30 17:42 17:54 18:14 16:30 16:44 16:56 17:04 17:15 17:17 17:29 17:38 17:50 18:03 18:05 16:41 16:52 17:04 17:12 17:23 17:25 17:37 17:46 17:58 18:10 18:23 16:45 17:00 17:12 17:20 17:31 17:35 17:46 17:54 18:05 18:17 18:35 16:55 17:09 17:21 17:29 17:40 17:45 17:56 18:04 18:15 18:26 18:46 17:08 17:19 17:31 17:39 17:50 17:55 18:06 18:14 18:25 18:37 18:57 17:17 17:31 17:43 17:51 18:02 18:07 18:18 18:26 18:37 18:48 18:53 17:28 17:39 17:51 17:59 18:10 18:20 18:31 18:39 18:50 19:02 19:05 17:40 17:53 18:03 18:10 18:19 18:29 17:53 18:03 18:13 18:20 18:29 18:35 18:46 18:54 19:05 19:16 19:23 18:05 18:18 18:28 18:35 18:44 18:50 18:59 19:06 19:16 19:27 19:35 18:23 18:33 18:43 18:50 18:59 19:05 19:14 19:21 19:31 19:41 19:53 18:35 18:48 18:58 19:05 19:14 19:25 19:34 19:41 19:51 20:02 20:06 18:53 19:03 19:13 19:20 19:29 19:45 19:54 20:01 20:11 20:21 20:28 19:05 19:18 19:28 19:35 19:44 19:54 19:23 19:33 19:43 19:50 19:59 20:05 20:14 20:21 20:31 20:42 20:46 19:35 19:48 19:58 20:05 20:14 20:25 20:34 20:41 20:51 21:01 21:08 19:53 20:03 20:12 20:19 20:26 20:36 20:06 20:18 20:26 20:32 20:39 20:45 20:54 21:01 21:11 21:22 21:26 20:28 20:38 20:46 20:52 20:59 21:05 21:12 21:18 21:26 21:35 21:48 20:46 20:58 21:06 21:12 21:19 21:25 21:32 21:38 21:46 21:56 22:06 21:08 21:18 21:26 21:32 21:39 21:45 21:52 21:58 22:06 22:15 22:28 21:26 21:38 21:46 21:52 21:59 22:05 22:12 22:18 22:26 22:36 22:46 21:48 21:58 22:06 22:12 22:19 22:25 22:32 22:38 22:46 22:55 23:08 22:06 22:18 22:26 22:32 22:39 22:45 22:52 22:58 23:06 23:16 23:26 22:28 22:38 22:46 22:52 22:59 23:05 23:12 23:18 23:26 23:35 23:48 22:46 22:58 23:06 23:12 23:19 23:25 23:32 23:38 23:46 23:56 0:06 23:08 23:18 23:26 23:32 23:39 23:49 23:26 23:38 23:46 23:52 23:59 0:05 0:12 0:18 0:26 0:36 0:56 23:48 23:58 0:06 0:12 0:19 0:29 0:06 0:18 0:26 0:32 0:39 0:49 4-70

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Level . Advanced Blocking Chapter 4. Schedule Blocking The next trip that needs to be hooked is the : departure from Sand Point (for the moment, focus on completing all the existing blocks and ignore pull-outs). This can be hooked with the : arrival on block . Continue block through the rest of the day--a very short rest of the day, since now pulls in at : . Next, look at the : trip from Wishram. The only trip available to hook to this trip is the : arrival on block . Two minutes layover is very tight, and at the end of the : trip, there is another two-minute layover at Rugby Circle. The work rules allow this, and our operat- ing knowledge tells us this works on a regular basis, so assign the : trip to block . Continuing with block , The : southbound trip arrives at Wishram at : , and the schedule calls for it to hook with the : trip. This would be three consecutive trips with only two minutes of layover each, so try to reassign the : trip to another block and hook the : arrival with a later trip at : . Continuing to hook trips would result in a pull-in time of : for block . The schedule sheet on the following page shows the completed blocks and . The change in hooking trips has another side benefit. The only trip available to hook with the : trip is the : arrival at Wishram. The schedule originally called for this block to pull out at : , make one round trip, and pull in at : . As stressed in the intermediate block- ing section, it is almost always advantageous to reblock to lengthen very short blocks. So this change ends up meeting two objectives: to provide adequate layover time and to avoid pulling out a bus for only one or two trips. Advanced schedulers would realize at this point that the change in hooking trips creates another problem. The : trip was originally scheduled to be hooked with a block that pulls out at : and finishes its first southbound trip at : . If you assign the : trip to block instead of to its original block, then you are left with a block that does only one round-trip before pulling in. A similar problem occurred in the intermediate section and was addressed by shifting blocks at the end of the exercise, but now that you are aware of the issue, you can catch it at this point before you complete the rest of the blocking, and save yourself from hav- ing to redo it later. This is an example of how a seemingly great solution can have unexpected impacts down the road. It reinforces the importance of looking at the bigger picture while analyzing any one ele- ment of scheduling. In this case, your blocking solution is threefold: Keep the hook between the : arrival trip and the : departure trip. Hook the : arrival trip with the : departure trip. Pull in block after it arrives at Wishram at : . 4-71

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Chapter 4. Schedule Blocking Level . Advanced Blocking S C H E D U L E S H E E T w ith c hang e s to b lo c ks 9 6 0 5 and 9 6 1 1 Ro ute 96 IN EF F: M O N D AY T H R U F RID AY P art 2 NO RTHB O U ND S O UTHB O U ND OUT Libby Sand Pasco Pasco Pasco Rugby Rugby Pasco Pasco Pasco Sand Libby NEXT IN BLK GAR Wishrm Point Essex Havre Willis Circle Circle Willis Havre Essex Point Wishrm TRIP BLK GAR 9610 13:53 14:03 14:14 14:21 14:31 14:35 14:45 14:52 15:03 15:14 15:23 9610 9603 14:05 14:18 14:29 14:36 14:46 14:50 15:00 15:07 15:18 15:30 15:35 9603 9608 14:23 14:33 14:44 14:51 15:01 15:05 15:15 15:22 15:33 15:44 15:58 9608 9602 14:35 14:48 14:59 15:06 15:16 15:20 15:30 15:37 15:48 16:00 16:05 9602 9611 15:23 15:33 15:44 15:52 16:03 16:15 16:23 9611 9605 14:53 15:03 15:14 15:21 15:31 15:45 15:56 16:04 16:15 16:28 16:30 9605 9609 15:05 15:18 15:29 15:36 15:46 15:57 16:08 16:16 16:27 16:39 16:41 9609 9610 15:23 15:33 15:44 15:51 16:01 16:09 16:20 16:28 16:39 16:52 16:55 9610 9603 15:35 15:48 15:59 16:06 16:16 16:20 16:32 16:41 16:53 17:05 17:08 9603 16:19 16:29 16:41 16:50 17:02 17:15 17:17 9612 15:43 15:58 16:09 16:16 16:26 16:37 16:49 16:58 17:10 17:22 17:17 9612 9608 15:58 16:08 16:19 16:26 16:36 16:45 16:57 17:06 17:18 17:31 17:40 9608 9602 16:05 16:18 16:29 16:36 16:46 16:53 17:05 17:14 17:26 17:38 17:53 9602 16:11 16:26 16:38 16:46 16:57 17:01 17:13 17:22 17:34 17:47 18:07 9611 16:23 16:34 16:46 16:54 17:05 17:09 17:21 17:30 17:42 17:54 9611 18:14 9605 16:30 16:44 16:56 17:04 17:15 17:17 17:29 17:38 17:50 18:03 18:35 9605 16:41 16:52 17:04 17:12 17:23 17:25 17:37 17:46 17:58 18:10 18:23 16:45 17:00 17:12 17:20 17:31 17:35 17:46 17:54 18:05 18:17 18:35 16:55 17:09 17:21 17:29 17:40 17:45 17:56 18:04 18:15 18:26 18:46 17:08 17:19 17:31 17:39 17:50 17:55 18:06 18:14 18:25 18:37 18:57 17:17 17:31 17:43 17:51 18:02 18:07 18:18 18:26 18:37 18:48 18:53 17:28 17:39 17:51 17:59 18:10 18:20 18:31 18:39 18:50 19:02 19:05 17:40 17:53 18:03 18:10 18:19 18:29 17:53 18:03 18:13 18:20 18:29 18:35 18:46 18:54 19:05 19:16 19:23 18:05 18:18 18:28 18:35 18:44 18:50 18:59 19:06 19:16 19:27 19:35 18:23 18:33 18:43 18:50 18:59 19:05 19:14 19:21 19:31 19:41 19:53 9605 18:35 18:48 18:58 19:05 19:14 19:25 19:34 19:41 19:51 20:02 20:06 9605 18:53 19:03 19:13 19:20 19:29 19:45 19:54 20:01 20:11 20:21 20:28 19:05 19:18 19:28 19:35 19:44 19:54 19:23 19:33 19:43 19:50 19:59 20:05 20:14 20:21 20:31 20:42 20:46 19:35 19:48 19:58 20:05 20:14 20:25 20:34 20:41 20:51 21:01 21:08 19:53 20:03 20:12 20:19 20:26 20:36 9605 20:06 20:18 20:26 20:32 20:39 20:45 20:54 21:01 21:11 21:22 21:26 9605 20:28 20:38 20:46 20:52 20:59 21:05 21:12 21:18 21:26 21:35 21:48 20:46 20:58 21:06 21:12 21:19 21:25 21:32 21:38 21:46 21:56 22:06 21:08 21:18 21:26 21:32 21:39 21:45 21:52 21:58 22:06 22:15 22:28 9605 21:26 21:38 21:46 21:52 21:59 22:05 22:12 22:18 22:26 22:36 22:46 9605 21:48 21:58 22:06 22:12 22:19 22:25 22:32 22:38 22:46 22:55 23:08 22:06 22:18 22:26 22:32 22:39 22:45 22:52 22:58 23:06 23:16 23:26 22:28 22:38 22:46 22:52 22:59 23:05 23:12 23:18 23:26 23:35 23:48 9605 22:46 22:58 23:06 23:12 23:19 23:25 23:32 23:38 23:46 23:56 0:06 9605 23:08 23:18 23:26 23:32 23:39 23:49 23:26 23:38 23:46 23:52 23:59 0:05 0:12 0:18 0:26 0:36 0:56 23:48 23:58 0:06 0:12 0:19 0:29 9605 0:06 0:18 0:26 0:32 0:39 9605 0:49 4-72

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Level . Advanced Blocking Chapter 4. Schedule Blocking Make the revisions to block to pull in after arriving at Wishram at : , and then com- plete the blocking for the all-day blocks. The results are shown below. S C H E D U LE S H E E T w ith re vision to blo ck 960 5 an d com ple tion of all-d a y block s R ou te 96 IN EFF : M O N D A Y T H R U F R ID A Y P art 2 N O R T H BO U N D S O U T H BO U N D OUT Libby Sand Pasco Pasco Pasco Rugby Rugby Pasco Pasco Pasco Sand Libby NEXT IN BLK GAR Wishrm Point Essex Havre Willis Circle Circle Willis Havre Essex Point Wishrm TRIP BLK GAR 9610 13:53 14:03 14:14 14:21 14:31 14:35 14:45 14:52 15:03 15:14 15:23 9610 9603 14:05 14:18 14:29 14:36 14:46 14:50 15:00 15:07 15:18 15:30 15:35 9603 9608 14:23 14:33 14:44 14:51 15:01 15:05 15:15 15:22 15:33 15:44 15:58 9608 9602 14:35 14:48 14:59 15:06 15:16 15:20 15:30 15:37 15:48 16:00 16:05 9602 9611 15:23 15:33 15:44 15:52 16:03 16:15 16:23 9611 9605 14:53 15:03 15:14 15:21 15:31 15:45 15:56 16:04 16:15 16:28 16:30 9605 9609 15:05 15:18 15:29 15:36 15:46 15:57 16:08 16:16 16:27 16:39 16:41 9609 9610 15:23 15:33 15:44 15:51 16:01 16:09 16:20 16:28 16:39 16:52 16:55 9610 9603 15:35 15:48 15:59 16:06 16:16 16:20 16:32 16:41 16:53 17:05 17:08 9603 16:19 16:29 16:41 16:50 17:02 17:15 17:17 9612 15:43 15:58 16:09 16:16 16:26 16:37 16:49 16:58 17:10 17:22 17:17 9612 9608 15:58 16:08 16:19 16:26 16:36 16:45 16:57 17:06 17:18 17:31 17:40 9608 9602 16:05 16:18 16:29 16:36 16:46 16:53 17:05 17:14 17:26 17:38 17:53 9602 16:11 16:26 16:38 16:46 16:57 17:01 17:13 17:22 17:34 17:47 18:07 9611 16:23 16:34 16:46 16:54 17:05 17:09 17:21 17:30 17:42 17:54 9611 18:14 9605 16:30 16:44 16:56 17:04 17:15 17:17 17:29 17:38 17:50 18:03 9605 18:23 9609 16:41 16:52 17:04 17:12 17:23 17:25 17:37 17:46 17:58 18:10 18:23 9609 16:45 17:00 17:12 17:20 17:31 17:35 17:46 17:54 18:05 18:17 18:35 9610 16:55 17:09 17:21 17:29 17:40 17:45 17:56 18:04 18:15 18:26 9610 18:46 9603 17:08 17:19 17:31 17:39 17:50 17:55 18:06 18:14 18:25 18:37 9603 18:57 17:17 17:31 17:43 17:51 18:02 18:07 18:18 18:26 18:37 18:48 18:53 17:28 17:39 17:51 17:59 18:10 18:20 18:31 18:39 18:50 19:02 19:05 9608 17:40 17:53 18:03 18:10 18:19 9608 18:29 9602 17:53 18:03 18:13 18:20 18:29 18:35 18:46 18:54 19:05 19:16 19:23 9602 18:05 18:18 18:28 18:35 18:44 18:50 18:59 19:06 19:16 19:27 19:35 9609 18:23 18:33 18:43 18:50 18:59 19:05 19:14 19:21 19:31 19:41 19:53 9609 18:35 18:48 18:58 19:05 19:14 19:25 19:34 19:41 19:51 20:02 20:06 18:53 19:03 19:13 19:20 19:29 19:45 19:54 20:01 20:11 20:21 20:28 19:05 19:18 19:28 19:35 19:44 19:54 9602 19:23 19:33 19:43 19:50 19:59 20:05 20:14 20:21 20:31 20:42 20:46 9602 19:35 19:48 19:58 20:05 20:14 20:25 20:34 20:41 20:51 21:01 21:08 9609 19:53 20:03 20:12 20:19 20:26 9609 20:36 20:06 20:18 20:26 20:32 20:39 20:45 20:54 21:01 21:11 21:22 21:26 20:28 20:38 20:46 20:52 20:59 21:05 21:12 21:18 21:26 21:35 21:48 9602 20:46 20:58 21:06 21:12 21:19 21:25 21:32 21:38 21:46 21:56 22:06 9602 21:08 21:18 21:26 21:32 21:39 21:45 21:52 21:58 22:06 22:15 22:28 21:26 21:38 21:46 21:52 21:59 22:05 22:12 22:18 22:26 22:36 22:46 21:48 21:58 22:06 22:12 22:19 22:25 22:32 22:38 22:46 22:55 23:08 9602 22:06 22:18 22:26 22:32 22:39 22:45 22:52 22:58 23:06 23:16 23:26 9602 22:28 22:38 22:46 22:52 22:59 23:05 23:12 23:18 23:26 23:35 23:48 22:46 22:58 23:06 23:12 23:19 23:25 23:32 23:38 23:46 23:56 0:06 23:08 23:18 23:26 23:32 23:39 23:49 9602 23:26 23:38 23:46 23:52 23:59 0:05 0:12 0:18 0:26 0:36 9602 0:56 23:48 23:58 0:06 0:12 0:19 0:29 0:06 0:18 0:26 0:32 0:39 0:49 4-73

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Chapter 4. Schedule Blocking Level . Advanced Blocking Finally, finish blocking the PM-only blocks. Recall that the numbering scheme in this example is by pull-out time, so block is correctly numbered. Block is the pull-out at : , block at : , and block at : . The PM blocks are highlighted in the final PM schedule sheet below. S C H E D U L E S H E E T w ith P M b lo c ks ad d e d Ro ute 96 IN EF F: M O N D AY T H R U F RID AY P art 2 NO RTHB O U ND S O UTHB O U ND OUT Libby Sand Pasco Pasco Pasco Rugby Rugby Pasco Pasco Pasco Sand Libby NEXT IN BLK GAR Wishrm Point Essex Havre Willis Circle Circle Willis Havre Essex Point Wishrm TRIP BLK GAR 9610 13:53 14:03 14:14 14:21 14:31 14:35 14:45 14:52 15:03 15:14 15:23 9610 9603 14:05 14:18 14:29 14:36 14:46 14:50 15:00 15:07 15:18 15:30 15:35 9603 9608 14:23 14:33 14:44 14:51 15:01 15:05 15:15 15:22 15:33 15:44 15:58 9608 9602 14:35 14:48 14:59 15:06 15:16 15:20 15:30 15:37 15:48 16:00 16:05 9602 9611 15:23 15:33 15:44 15:52 16:03 16:15 16:23 9611 9605 14:53 15:03 15:14 15:21 15:31 15:45 15:56 16:04 16:15 16:28 16:30 9605 9609 15:05 15:18 15:29 15:36 15:46 15:57 16:08 16:16 16:27 16:39 16:41 9609 9610 15:23 15:33 15:44 15:51 16:01 16:09 16:20 16:28 16:39 16:52 16:55 9610 9603 15:35 15:48 15:59 16:06 16:16 16:20 16:32 16:41 16:53 17:05 17:08 9603 9614 16:19 16:29 16:41 16:50 17:02 17:15 17:17 9614 9612 15:43 15:58 16:09 16:16 16:26 16:37 16:49 16:58 17:10 17:22 17:28 9612 9608 15:58 16:08 16:19 16:26 16:36 16:45 16:57 17:06 17:18 17:31 17:40 9608 9602 16:05 16:18 16:29 16:36 16:46 16:53 17:05 17:14 17:26 17:38 17:53 9602 9613 16:11 16:26 16:38 16:46 16:57 17:01 17:13 17:22 17:34 17:47 18:05 9613 9611 16:23 16:34 16:46 16:54 17:05 17:09 17:21 17:30 17:42 17:54 9611 18:14 9605 16:30 16:44 16:56 17:04 17:15 17:17 17:29 17:38 17:50 18:03 9605 18:23 9609 16:41 16:52 17:04 17:12 17:23 17:25 17:37 17:46 17:58 18:10 18:23 9609 9615 16:45 17:00 17:12 17:20 17:31 17:35 17:46 17:54 18:05 18:17 18:35 9615 9610 16:55 17:09 17:21 17:29 17:40 17:45 17:56 18:04 18:15 18:26 9610 18:46 9603 17:08 17:19 17:31 17:39 17:50 17:55 18:06 18:14 18:25 18:37 9603 18:57 9614 17:17 17:31 17:43 17:51 18:02 18:07 18:18 18:26 18:37 18:48 18:53 9614 9612 17:28 17:39 17:51 17:59 18:10 18:20 18:31 18:39 18:50 19:02 19:05 9612 9608 17:40 17:53 18:03 18:10 18:19 9608 18:29 9602 17:53 18:03 18:13 18:20 18:29 18:35 18:46 18:54 19:05 19:16 19:23 9602 9613 18:05 18:18 18:28 18:35 18:44 18:50 18:59 19:06 19:16 19:27 19:35 9613 9609 18:23 18:33 18:43 18:50 18:59 19:05 19:14 19:21 19:31 19:41 19:53 9609 9615 18:35 18:48 18:58 19:05 19:14 19:25 19:34 19:41 19:51 20:02 20:06 9615 9614 18:53 19:03 19:13 19:20 19:29 19:45 19:54 20:01 20:11 20:21 20:28 9614 9612 19:05 19:18 19:28 19:35 19:44 9612 19:54 9602 19:23 19:33 19:43 19:50 19:59 20:05 20:14 20:21 20:31 20:42 20:46 9602 9613 19:35 19:48 19:58 20:05 20:14 20:25 20:34 20:41 20:51 21:01 21:08 9613 9609 19:53 20:03 20:12 20:19 20:26 9609 20:36 9615 20:06 20:18 20:26 20:32 20:39 20:45 20:54 21:01 21:11 21:22 21:26 9615 9614 20:28 20:38 20:46 20:52 20:59 21:05 21:12 21:18 21:26 21:35 21:48 9614 9602 20:46 20:58 21:06 21:12 21:19 21:25 21:32 21:38 21:46 21:56 22:06 9602 9613 21:08 21:18 21:26 21:32 21:39 21:45 21:52 21:58 22:06 22:15 22:28 9613 9615 21:26 21:38 21:46 21:52 21:59 22:05 22:12 22:18 22:26 22:36 22:46 9615 9614 21:48 21:58 22:06 22:12 22:19 22:25 22:32 22:38 22:46 22:55 23:08 9614 9602 22:06 22:18 22:26 22:32 22:39 22:45 22:52 22:58 23:06 23:16 23:26 9602 9613 22:28 22:38 22:46 22:52 22:59 23:05 23:12 23:18 23:26 23:35 23:48 9613 9615 22:46 22:58 23:06 23:12 23:19 23:25 23:32 23:38 23:46 23:56 0:06 9615 9614 23:08 23:18 23:26 23:32 23:39 9614 23:49 9602 23:26 23:38 23:46 23:52 23:59 0:05 0:12 0:18 0:26 0:36 9602 0:56 9613 23:48 23:58 0:06 0:12 0:19 9613 0:29 9615 0:06 0:18 0:26 0:32 0:39 9615 0:49 4-74

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Level . Advanced Blocking Chapter 4. Schedule Blocking Once all the blocks are finished, re-calculate the Block Summary table and once again calculate the mileage. The new Hours and Mileage summary tables are shown below. Hours Summary B loc k G arage D epart G arage A rrive P latform H ours 9601 3:45 8:57 5:12 9602 4:10 24:56 20:46 9603 4:15 18:57 14:42 9604 4:39 9:46 5:07 9605 4:55 18:23 13:28 9606 4:59 8:46 3:47 9607 6:05 9:57 3:52 9608 6:17 18:29 12:12 9609 7:05 20:36 13:31 9610 7:17 18:46 11:29 9611 15:23 18:14 2:51 9612 15:43 19:54 4:11 9613 16:11 0:29 8:18 9614 16:19 23:49 7:30 9615 16:45 0:49 7:44 Total 134:40 tripper A short piece of work whose total Mileage Summary time is less than that specified as B l oc k 96 N B T rip s 96A N B T rip s 96 N B T rip s f rom E ssex 9 6 S B T rip s 96A S B Tr ip s P ul l T rip s Li bb y/ W ish ram P ul l T rip s S an d P oi nt P ul l T rip s P a sco E sse x P ul l T rip s R ug by Ci rcl e M il ea ge constituting a full-time run. A tripper 9 60 1 9 60 2 3 11 2 3 12 2 2 1 1 57 . 3 21 5. 1 is often a piece of work in the AM 9 60 3 8 1 8 1 2 14 9. 2 or PM peak period that cannot be 9 60 4 9 60 5 1 3 7 2 3 7 1 2 1 54 . 0 13 2. 5 combined with another piece of 9 60 6 2 2 2 39 . 6 work to form a split run because of 9 60 7 9 60 8 2 1 7 2 1 6 2 1 1 41 . 8 11 7. 3 insufficient hours, excessive swing 9 60 9 6 3 5 3 1 1 13 6. 3 time, or excessive spread time. 9 61 0 9 61 1 1 6 1 1 6 2 2 1 1 11 2. 8 29 . 6 Trippers are often operated by 9 61 2 1 1 1 1 1 1 1 41 . 1 extraboard or part-time operators. 9 61 3 9 61 4 2 1 3 4 1 2 1 3 4 1 1 2 85 . 4 78 . 4 Tripper can also refer to a vehicle 9 61 5 5 1 5 1 1 88 . 6 that pulls out, makes no more than Total 42 40 3 43 40 8 9 3 10 1378.7 one round-trip, and pulls in. 4-75

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Chapter 4. Schedule Blocking Level . Advanced Blocking Below is a comparison showing what these changes cost. Existing Proposed Change No. of PM Peak Buses + Platform Hours : : + : Platform Miles . . + . The change added the equivalent of half of an operator. Actually, it added two two-hour trippers, which may or may not be a problem for the runcut, depending on what the other blocks at this route's garage look like. The Block Summary Table shows that three of the five PM pull-out blocks continue to be close to eight hours in length, compared to two of those blocks that were on the original schedule. There will have to be some re-working of the runs in order to fit the new block profile, but at least one more pull-out to pull-in late run will be avail- able with only minor changes to their times. We review the other blocks in the Block Summary carefully to make sure the changed blocks do not set up a runcutting problem. For example, if one of the PM pull-outs stayed out to : or : , forming a five-hour block with a late pull-in, it could not easily be worked into any run. This is a topic for the Chapter : Runcutting chapter, but is also an example of how schedulers must consider all aspects of scheduling when working on one particular problem. Block could be a problem in this regard. One of the secrets to being a good scheduler is being willing to tinker constantly with the schedules--even when you think you are finished. In this case, examine how block might be changed. Specifically, instead of pulling in when it does, could its last trip hook with another trip, preferably from a longer all-day block? In our most recent schedule sheet above, the last trip on block arrives at Rugby Circle at : and pulls in. The next southbound trip departing from Rugby Circle is at : on block . This is exactly the kind of swap we were hoping to find. Pull block in, and hook the trip arriving at : on block with the trip leaving at : . The affected trips are shown below, followed by the final revised Block Sheet. 4-76

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Level . Advanced Blocking Chapter 4. Schedule Blocking S C HE D UL E S HE E T with 9 6 0 2 -9 6 1 2 s wap - F INA L S HE E T R o u te 96 IN EF F : M O N D A Y T H R U F R ID A Y P art 2 N O R TH B O U N D S O U TH B O U N D OUT Libby Sand Pasco Pasco Pasco Rugby Rugby Pasco Pasco Pasco Sand Libby NEXT IN BLK GAR Wishrm Point Essex Havre Willis Circle Circle Willis Havre Essex Point Wishrm TRIP BLK GAR 9612 19:05 19:18 19:28 19:35 19:44 20:05 20:14 20:21 20:31 20:42 20:46 9612 9602 19:23 19:33 19:43 19:50 19:59 9602 20:09 9613 19:35 19:48 19:58 20:05 20:14 20:25 20:34 20:41 20:51 21:01 21:08 9613 9609 19:53 20:03 20:12 20:19 20:26 9609 20:36 9615 20:06 20:18 20:26 20:32 20:39 20:45 20:54 21:01 21:11 21:22 21:26 9615 9614 20:28 20:38 20:46 20:52 20:59 21:05 21:12 21:18 21:26 21:35 21:48 9614 9612 20:46 20:58 21:06 21:12 21:19 21:25 21:32 21:38 21:46 21:56 22:06 9612 9613 21:08 21:18 21:26 21:32 21:39 21:45 21:52 21:58 22:06 22:15 22:28 9613 9615 21:26 21:38 21:46 21:52 21:59 22:05 22:12 22:18 22:26 22:36 22:46 9615 9614 21:48 21:58 22:06 22:12 22:19 22:25 22:32 22:38 22:46 22:55 23:08 9614 9612 22:06 22:18 22:26 22:32 22:39 22:45 22:52 22:58 23:06 23:16 23:26 9612 9613 22:28 22:38 22:46 22:52 22:59 23:05 23:12 23:18 23:26 23:35 23:48 9613 9615 22:46 22:58 23:06 23:12 23:19 23:25 23:32 23:38 23:46 23:56 0:06 9615 9614 23:08 23:18 23:26 23:32 23:39 9614 23:49 9612 23:26 23:38 23:46 23:52 23:59 0:05 0:12 0:18 0:26 0:36 9612 0:56 9613 23:48 23:58 0:06 0:12 0:19 9613 0:29 9615 0:06 0:18 0:26 0:32 0:39 9615 0:49 4-77

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Chapter 4. Schedule Blocking Level . Advanced Blocking Revised Blocking Sheet - Multiple Terminals ROUTE 96 Special Instructions: DAY Weekday Goal: 7-9 minutes minimum layover time per round trip DATE 15-Sep-07 7 minutes OK before 5:00/after 19:45 Northbound Southbound Depart Depart Depart Arrive Depart Arrive Arrive Available Libby Sand Pasco Rugby Rugby Sand Libby for next trip Block # Pull Out Wishram Point Essex Circle Circle Point Wishram (arrival + Pull In NB1 NB2 midroute SB2 SB1 layover) 9601 3:45 4:05 4:41 4:50 5:23 5:35 5:35 6:16 6:20 6:57 7:05 7:05 7:50 7:55 8:37 8:57 9602 4:10 4:20 4:53 5:05 5:05 5:46 5:50 6:27 6:45 6:45 7:30 7:35 8:17 8:35 8:35 9:16 9:22 9:59 10:05 10:05 10:44 10:52 11:29 11:35 11:35 12:14 12:22 12:59 13:05 13:05 13:44 13:50 14:30 14:36 14:35 15:16 15:20 16:00 16:05 16:05 16:46 16:53 17:38 17:53 17:53 18:29 18:35 19:16 19:23 19:23 19:59 20:09 9603 4:15 4:35 5:11 5:20 5:57 6:05 6:05 6:46 6:50 7:32 7:45 7:45 8:30 8:35 9:17 9:35 9:35 10:14 10:22 10:59 11:05 11:05 11:44 11:52 12:29 12:35 12:35 13:14 13:22 13:59 14:05 14:05 14:46 14:50 15:30 15:35 15:35 16:16 16:20 17:05 17:08 17:08 17:50 17:55 18:37 18:57 9604 4:39 4:59 5:31 5:35 6:12 6:19 6:19 6:56 7:05 7:46 7:57 7:57 8:40 8:45 9:26 9:46 9605 4:55 5:05 5:37 5:49 5:49 6:26 6:35 7:12 7:17 7:17 8:00 8:05 8:46 8:53 8:53 9:31 9:37 10:13 10:23 10:23 10:59 11:07 11:43 11:53 11:53 12:29 12:37 13:13 13:23 13:23 13:59 14:05 14:44 14:53 14:53 15:31 15:45 16:28 16:30 16:30 17:15 17:17 18:03 18:23 4-78

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Level . Advanced Blocking Chapter 4. Schedule Blocking Revised Blocking Sheet - Multiple Terminals ROUTE 96 Special Instructions: DAY Weekday Goal: 7-9 minutes minimum layover time per round trip DATE 15-Sep-07 7 minutes OK before 5:00/after 19:45 Northbound Southbound Depart Depart Depart Arrive Depart Arrive Arrive Available Libby Sand Pasco Rugby Rugby Sand Libby for next trip Block # Pull Out Wishram Point Essex Circle Circle Point Wishram (arrival + Pull In NB1 NB2 midroute SB2 SB1 layover) 9606 4:59 5:19 5:56 6:05 6:42 6:57 6:57 7:40 7:45 8:26 8:46 9607 6:05 6:25 7:10 7:15 7:57 8:05 8:05 8:50 8:55 9:37 9:57 9608 6:17 6:37 7:20 7:25 8:06 8:23 8:23 9:02 9:07 9:48 9:53 9:53 10:29 10:37 11:13 11:23 11:23 11:59 12:07 12:43 12:53 12:53 13:29 13:35 14:13 14:23 14:23 15:01 15:05 15:44 15:58 15:58 16:36 16:45 17:31 17:40 17:40 18:19 18:29 9609 7:05 7:25 8:10 8:15 8:57 9:05 9:05 9:44 9:52 10:29 10:35 10:35 11:14 11:22 11:59 12:05 12:05 12:44 12:52 13:29 13:35 13:35 14:16 14:20 15:00 15:05 15:05 15:46 15:57 16:39 16:41 16:41 17:23 17:25 18:10 18:23 18:23 18:59 19:05 19:41 19:53 19:53 20:26 20:36 9610 7:17 7:37 8:20 8:25 9:06 9:23 9:23 9:59 10:07 10:43 10:53 10:53 11:29 11:37 12:13 12:23 12:23 12:59 13:07 13:43 13:53 13:53 14:31 14:35 15:14 15:23 15:23 16:01 16:09 16:52 16:55 16:55 17:40 17:45 18:26 18:46 4-79

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Chapter 4. Schedule Blocking Level . Advanced Blocking Revised Blocking Sheet - Multiple Terminals ROUTE 96 Special Instructions: DAY Weekday Goal: 7-9 minutes minimum layover time per round trip DATE 15-Sep-07 7 minutes OK before 5:00/after 19:45 Northbound Southbound Depart Depart Depart Arrive Depart Arrive Arrive Available Libby Sand Pasco Rugby Rugby Sand Libby for next trip Block # Pull Out Wishram Point Essex Circle Circle Point Wishram (arrival + Pull In NB1 NB2 midroute SB2 SB1 layover) 9611 15:23 15:33 16:15 16:23 16:23 17:05 17:09 17:54 18:14 9612 15:43 15:58 16:26 16:37 17:22 17:28 17:28 18:10 18:20 19:02 19:05 19:05 19:44 20:05 20:42 20:46 20:46 21:19 21:25 21:56 22:06 22:06 22:39 22:45 23:16 23:26 23:26 23:59 0:05 0:36 0:56 9613 16:11 16:26 16:57 17:01 17:47 18:05 18:05 18:44 18:50 19:27 19:35 19:35 20:14 20:25 21:01 21:08 21:08 21:39 21:45 22:15 22:28 22:28 22:59 23:05 23:35 23:48 23:48 0:19 0:29 9614 16:19 16:29 17:15 17:17 17:17 18:02 18:07 18:48 18:53 18:53 19:29 19:45 20:21 20:28 20:28 20:59 21:05 21:35 21:48 21:48 22:19 22:25 22:55 23:08 23:08 23:39 23:49 9615 16:45 17:00 17:31 17:35 18:17 18:35 18:35 19:14 19:25 20:02 20:06 20:06 20:39 20:45 21:22 21:26 21:26 21:59 22:05 22:36 22:46 22:46 23:19 23:25 23:56 0:06 0:06 0:39 0:49 4-80

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Level . Advanced Blocking Chapter 4. Schedule Blocking Once all the blocks are finished, recalculate the Block Summary table and the mileage. The final Hours and Mileage summary tables are shown below. Final Hours Summary B loc k G arage D epart G arage A rrive P latform H ours 9601 3:45 8:57 5:12 9602 4:10 20:09 15:59 9603 4:15 18:57 14:42 9604 4:39 9:46 5:07 9605 4:55 18:23 13:28 9606 4:59 8:46 3:47 9607 6:05 9:57 3:52 9608 6:17 18:29 12:12 9609 7:05 20:36 13:31 9610 7:17 18:46 11:29 9611 15:23 18:14 2:51 9612 15:43 0:56 9:13 9613 16:11 0:29 8:18 9614 16:19 23:49 7:30 9615 16:45 0:49 7:44 Total 134:55 Final Mileage Summary 96 N B Trips P ull Trips P ull Trips P ull Trips P ull Trips B loc k 96 N B Trips 96A N B Trips from E s s ex 96 S B Trips 96A S B Trips Libby /W is hram S and P oint P as c o E s s ex R ugby C irc le M ileage 9601 3 3 2 57.3 9602 8 2 8 2 2 157.9 9603 8 1 8 1 2 149.2 9604 3 3 2 54.0 9605 1 7 2 7 1 1 132.5 9606 2 2 2 39.6 9607 2 2 2 41.8 9608 1 7 1 6 1 1 117.3 9609 6 3 5 3 1 1 136.3 9610 1 6 1 6 2 112.8 9611 1 2 1 1 29.6 9612 4 1 1 5 1 1 1 98.3 9613 2 3 1 2 3 1 1 85.4 9614 1 4 1 4 2 78.4 9615 5 1 5 1 1 88.6 Total 42 40 3 43 40 8 9 3 10 1378.7 4-81

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Chapter 4. Schedule Blocking Level . Advanced Blocking The change has added : to the total platform hours ( : before the - swap, : now), which results in a total increase of : from the existing schedule before the running time and headway adjustments. This should result in a more efficient runcut. The new block graph is shown below. B loc k 4A 5A 6A 7A 8A 9A 10A 11A 12P 1P 2P 3P 4P 5P 6P 7P 8P 9P 10P 11P 12A H ours 345 857 9601 5:12 410 2009 9602 15:59 415 1857 9603 14:42 439 946 9604 5:07 455 1823 9605 13:28 459 846 9606 3:47 605 957 9607 3:52 617 1829 9608 12:12 705 2036 9609 13:31 717 1846 9610 11:29 1523 1814 9611 2:51 1543 2456 9612 9:13 1611 2429 9613 8:18 1619 2349 9614 7:30 1645 2449 9615 7:44 4-82

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Level . Advanced Blocking Chapter 4. Schedule Blocking Observations on the advanced blocking exercise include: When running times or headways change, you can expect to reblock all trips after the first changes go into effect. In this case, all blocks (with the exception of the AM-only blocks) changed as a result of changed running times and headways in the PM peak. Each element of the scheduling process affects other elements. Consideration of the effects of blocking on runcutting can result in changes, as seen in this example. This is an important point that can get lost in the process of breaking down "scheduling" into its components, as this manual necessarily does. Good schedulers always keep this point in mind. Computerized scheduling software packages simplify the blocking process (and all aspects of scheduling) greatly. This raises an obvious question: why go through these spreadsheet-based exercises at all if the computer can spit out the answer I need? There are many levels on which this question may be answered, from the basic com- puter axiom of Garbage In, Garbage Out to a sophisticated discussion of the algorithms used in scheduling packages. Here is the best answer: to be a scheduler, you need to think like a scheduler and to understand all aspects of the craft of scheduling. In using computerized packages, thinking like a scheduler helps you to see where criteria can be adjusted. In this case, you could specify that no block shorter than five hours can pull out after : . Experimenting with various criteria is one way to maximize the usefulness of a comput- erized software package. To do this effectively, though, you need to have a sense of which "tweaks" are most helpful. Working through spreadsheet-based or even by-hand scheduling exercises is a time-tested means of developing this sense. 4-83

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Chapter 4. Schedule Blocking Level . Advanced Blocking Applying Garages to Each Block In medium to large systems where routes travel a great distance and are through-routed from one side of town to the other, many routes work out of two (or more) garages. This can oc- cur due to the size of the route in terms of the large number of buses and can also be done to minimize to the extent possible the amount of deadhead miles and hours involved with pulling out and in. Assume that you are scheduling a through-route operated from two garages, one at each end of the route. The task for the scheduler is to get the respective blocks back to their home garages while minimizing operator pay hours. In the simplest example, buses pull out to either end of the route or to a midpoint such as downtown. As seen earlier, blocks do not necessarily end service at the same location where they begin service. Following normal blocking practice as discussed earlier, blocks will naturally end at ( ) the same place of the route where they be- gan, ( ) at downtown, or ( ) at the opposite end of the route. The goal is to eliminate as many of these "end opposites" as possible, or more formally, to minimize the number of runs that end in places that require long deadhead trips to reach the garage. There is no miracle way of making blocks end where they began. The scheduler deals with each block individually. The same-side start and finish blocks are checked off and forgotten about. Normally downtown starts or finishes are a "free square" which offers half the savings (half the deadhead of going from one side of the route to the other to pull in). The scheduler can check those off too, since there is no perfect solution and downtown is a legitimate place to start and end service. That leaves us with the "end opposite" blocks. There are only two potential actions for fixing these: ( ) re-hooking or ( ) creating extra trips. We discussed re-hooking in order to give us a better block length to aid the runcutting process. In the case of a long, through-routed line, we could also re-hook trips to yield a block which starts and finishes on the same side of the route. Care must be taken, though, that re-hooking works for both blocks involved. The resulting change must work for both. The concern of leav- ing a block that becomes a runcutting problem must also be considered. If the scheduler has to choose between the lesser of these two "evils" it is usually best to go with block length. That is probably the least expensive choice, as deadhead time and miles may well be less costly than a block whose pieces wind up as trippers. Creating extra trips may be desirable if they come at a time where ridership would benefit from them. Schedulers normally view any trips that are above what is needed to meet the standards for carrying passenger volume as "bad." In this instance, however, the added trips may not add all that much extra cost, since the mileage has to be operated anyway and the extra time in 4-84

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Level . Advanced Blocking Chapter 4. Schedule Blocking service over and above that required for deadheading may yield extra patronage. This is where the scheduler's good judgment comes into play. Midday Storage Lots A number of larger systems store buses during the day at a central location, usually near down- town. These central storage facilities may be as simple as a parking lot located under an ele- vated portion of a freeway or may be a dedicated lot with covered parking and full facilities for drivers and supervisors, including a waiting lounge. Sometimes a centrally located bus garage can be used to host these "foreign" blocks during the midday. This arrangement is especially handy for saving unnecessary deadheading of equipment and operators. The agencies that use central midday storage normally have suburban or interurban routes that operate from quite a distance out and would have a relatively long return back to their respective garages. Many of these routes are peak-direction-only express routes that require lengthy deadheads to pull in after the AM peak and to pull out before the PM peak. In most cases, these agencies have negotiated with their unions to eliminate the need to pay drivers to deadhead back to the garage, so there is a significant saving in both miles and plat- form hours. However, most systems do provide transportation back for those who want to return to the home garage. This is typically handled by sending selected pull-ins through the storage facility every to minutes to pick up any drivers wanting to go back. The process is reversed for the start of the PM peak. In cases where the labor agreement requires payment to drivers, the shuttles between the garage and the storage lot can be more frequent, on the order of every to minutes. The scheduler's responsibility here is to pick candidate blocks from the various routes and garages which would benefit from this scheme. Several garages may be involved, but con- strained parking space is often the limiting factor (the union contract may also specify a maxi- mum number of buses that can be stored). Besides picking out the blocks which would stay, the scheduler must also arrange a schedule of buses going back to the home garage from the pull-ins available. There is an obvious need to account for all of the storage buses to make sure that they are all needed to pull out for the PM, although they could be used on a different route ultimately returning to the home garage. Interlining on a Garage or System Basis Modern block optimizing software has given the scheduler the ability to throw a large garage's worth of blocks or a sector of a system into an electronic hopper and allow the software to try to reduce the number of blocks necessary to operate a given set of trips by looking sys- tem-wide or garage-wide at all interlining possibilities. The software adds a new dimension 4-85

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Chapter 4. Schedule Blocking Level . Advanced Blocking to the task by asking if certain key trips during peak times, when the number of buses is at a premium, can be moved by one or more minutes in order to effect a bus saving. One large transit system saved well over a dozen buses during the AM peak using this software in one sector of their service area. This resulted in monetary savings, but also in extensive deadhead- ing between terminals on different routes in order to achieve the savings. Operators also found themselves working a number of different routes during the course of their day. The upsides of using these block optimizers are obvious: The savings in peak buses can be significant The peak bus savings translates directly into run and operator reduction But, there are downsides also: The scheduler must know when and where to use this tool or what we will character- ize as needless interlining will occur. Remember that the computer does not "see" the movement of buses; it only accounts for the mathematical savings. This can result in some unexpected situations, such as two buses passing each other while deadheading to each other's former route in order to shave a couple of minutes off vehicle hours. This is particularly true during off-peak periods where headways are generally stable and random interlines would not normally be considered as a way of saving hours. The travel time information in the point-to-point deadhead table that drives the optimi- zation must be accurate and kept up-to-date. Otherwise, delays are spread to a number of routes, decreasing the overall on-time performance. Maintaining this large matrix is not a simple task. APC or AVL information needs to be available in large quantity and to be monitored regularly. The transit agency must use a scheduling package that offers the block optimizing routine as an extra cost add-on. Not all packages have this routine. To perform this kind of global optimization by hand is incredibly time-consuming and usually beyond what time is available to the scheduler to prepare for the next sign-up even without this extra step. The recommendation is that schedulers should always look to their knowledge of the route structure and route performance information before deciding on how to set the criteria guiding the block optimization software. Interlining stray peak-hour pieces is a rightful concern for the scheduler, but it is possible to go overboard with the block optimization tool. Common sense and knowledge of your system can guide you. 4-86

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Level . Advanced Blocking Chapter 4. Schedule Blocking alternate-fuel buses Route Assignments by Garage Buses using low-polluting fuels Many transit agencies periodically revisit which bus routes are assigned to which garages. in place of diesel or gasoline. Ongoing scheduling changes that add or reduce the number of buses operated on each route Examples of alternate fuels include may conflict with the capacity of a particular garage. Introduction of new types of vehicles compressed natural gas (CNG), (alternate-fuel, articulated buses) for use on specific routes may result in reassignment of liquefied natural gas (LNG), those routes to garages with the capacity to store and/or fuel these vehicles. Opening a new ethanol, methanol, and propane. garage usually triggers an analysis of this type. Electric or hybrid electric vehicles also fall within this definition. The scheduler's goal in route assignment is to minimize deadhead miles and hours within any system constraints (garage capacity, fueling capabilities, maintenance bays that can accom- modate articulated buses). Computerized scheduling software is very useful in this task, par- articulated bus ticularly for major changes such as the opening or closing of a garage. An extra-long (54 to 62 feet) bus with the rear body section A reconsideration of route assignments by garage does not need to be done more than once connected to the main body by a every five years or so--even less often if service levels are stable. The scheduling survey re- joint mechanism which allows the vealed that this is a common but not a universal practice among agencies that operate out of vehicle to bend when in operation multiple garages. for sharp turns and curves and yet have a continuous interior for passenger movement. 4-87

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Chapter 4. Schedule Blocking Level . Advanced Blocking LEVEL End of Schedule Blocking. 3 Runcutting continues on the next page. 4-88