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Level . The Basics Chapter 4. Schedule Blocking Blocking is not done 4.1 Basic Blocking--The Importance of Blocking Tip in isolation--it is an In Chapter we introduced the concept of blocking--breaking down a schedule intermediate step between writing LEVEL into assignments for individual buses. These assignments are called blocks and a schedule and developing driver assignments, and must be done 1 consist of a series of trips that are "hooked" together and assigned to a single vehicle. The vehicle trips that are linked together as part of the block may serve with the ultimate goal of developing multiple routes and may be operated by multiple operators. The block refers to efficient and "legal" driver work the work assignment for a single vehicle for a single service workday. pieces. Blocking is a main component of the scheduling process because it serves as the basis for the costs associated with operating the vehicle in revenue service and has a strong influence on the cost associated with work assignments for operators. blocking All blocking uses similar strategies and considerations. In this basic section, we will review the The process in which trips are blocking of the Route schedule in greater detail. The intermediate and advanced sections "hooked" together to form a vehicle consider aspects of blocking that are common in more complex schedules. assignment or block. block A vehicle (or train) assignment that includes the series of trips operated by each vehicle from the time it pulls out to the time it pulls in. A complete block includes a pull-out trip from the garage followed by one or (usually) more revenue trips and concluding with a pull-in trip back to the garage. 4-3

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Chapter 4. Schedule Blocking Level . The Basics Blocking a Simple Schedule master schedule The first step in the blocking process is to have a completed master schedule for each route or A document that displays all time depot to be blocked. In our case, the master schedule for Route is shown on page - . points and trips on a route. Usually includes run numbers, and block The scheduler must be thoroughly knowledgeable of all work rules and policies related to numbers, and pull-in and pull-out blocking before beginning. However, as stressed earlier, a good scheduler keeps all aspects of times. Used interchangeably in this scheduling in mind throughout the process. In developing blocks, it is also very important to manual with "headway sheet." have a thorough knowledge of the work rules regarding runcutting (assigning work to opera- tors, see Chapter ). Blocks that are "runcut friendly" optimize the efficiency of the entire layover time scheduling process. Later sections of this chapter will explain the difference between blocks The time between the scheduled that are "runcut friendly" and blocks that are not. arrival and departure of a vehicle Work rules and policies that are essential in blocking include: at a transit terminal. Often used interchangeably with "recovery Layover and recovery time time," although technically layover Layover locations time is rest time for the operator between trips while recovery time Interlining policies is time built into the schedule to ensure an on-time departure Layover and Recovery Time for the next trip. In this manual, The blocking process creates layovers and ensures that the bus has enough time in the round layover and recovery are calculated trip to stay on schedule. The terms "layover" and "recovery" refer to the time between trips, together and the total time between from the time a bus arrives at a terminal and the time the bus leaves the terminal to begin the trips is referred to as "layover." next trip. While layover and recovery are often calculated as a single unit of time, in theory they are intended for two different purposes. Recovery time is time allotted by management platform time to ensure that a bus can get back on schedule if it arrives at the terminal, or designated loca- Platform time, a phrase derived tion, slightly behind schedule. A driver could be expected to reduce or eliminate their recovery from the early 20th century days time if they arrive at the terminal behind schedule and need to leave quickly to begin the next when motormen and conductors trip. Layover time is time negotiated by union rules and by agency practice to give drivers a operated from the "platform" of a break at the end of a trip. Layover time is paid time for operators and is considered part of the streetcar, platform time includes all platform time. time when the operator is operating the vehicle. Layover time and pull-in and pull-out time are part of platform time, but report allowance and clear allowance, and travel time (unless part of a pull-in or pull-out) are not. Similarly, platform miles include all miles traveled while the In the advanced section the topic of interlining will be discussed. It should be noted now that block interlining can be applied not just operator is operating the vehicle. at the route level but among routes, at the garage level, as well. Also known as "vehicle hours." 4-4

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Level . The Basics Chapter 4. Schedule Blocking Understanding your While layover and recovery time are theoretically different, the fact is that this is time applied Tip properties rules on at the end of a trip, paid to the operator, and added to the time required to "turn the bus" and layover and recovery are essential complete the trip. Layover and recovery time are often calculated together and thought of as to blocking and schedule making. just one unit of time. In this manual, we will calculate layover and recovery together and will Properties with less flexible refer to the total time between trips as "layover." rules for calculating layover and recovery times will inevitably have Layover policy may be spelled out in the labor agreement, based on formal agency standards, less efficient schedules, as one or based on informal practices. Work rules vary across transit properties. Required layover minute of layover often makes the typically varies from none at all to % to % of the trip running time. Ten percent has been a difference between adding a bus to longtime standard within the industry. Some agencies specified either % of running time or a route or not. five minutes, whichever is greater. To optimize the blocking process, the scheduler must know whether the agency's layover policy represents a hard and fast rule that must be followed in all cases or a guideline that can be "bent" to optimize the blocking process and reduce peak bus requirements. Some agencies allow policy exceptions during peak hours only as long as the exceptions do not involve con- secutive trips. Given the potential for delays that cannot be reliably anticipated, such as traffic incidents, wheelchair boardings and alightings (helped somewhat by the use of ramps on low floor buses), and bicycle rack activity, many schedulers today provide more than % layover. Fifteen % is not unusual, and a number of systems schedule layover time as high as % of running time. Layover time is added to the round-trip running time in order to plan for the number of buses in the schedule. Where wider headways ( to minutes) are the norm, the amount of layover time in the schedule tends to be greater also, since there are fewer multiples of a - or - minute headway. Many systems operate a pulse schedule where everything meets at a central location or at an outlying transit center. In a pulse system, longer routes get correspondingly less layover. Linking long routes that are tight for time with shorter routes where layover is plentiful is an excellent strategy in these circumstances. 4-5

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Chapter 4. Schedule Blocking Level . The Basics Layover Location Tip Layover is rarely done in the middle of a route Many agencies limit the locations where layover can be taken. In a pulse system where many when passengers are on board, routes meet at a central location, layover may be scheduled at this location to facilitate trans- unless there is a timed meet at a fers or may be scheduled at the outer ends of the route to avoid congestion. Layover time is major stop on the route. Layover sometimes required at the end of each one-way trip, requiring a layover location at both ends is applied at the end of the route so of the route, but more often is applied to each round trip. A major factor in selecting layover that passengers are not required to locations is the availability of operator facilities. "sit through" a layover, and so that drivers can have a layover that is Layover time must be scheduled in a safe location where a bus can be parked without imped- free from passenger responsibili- ing traffic. Layover is usually taken at the end of the route where it does not inconvenience ties. Some layover time is often passengers. Routes with a one-way loop at one or both ends create challenges for identifying added to a timed meet location a layover location, since through ridership along the loop means that some passengers will to ensure that the meet will occur experience a delay. Layover time may also be assigned at key mid-route transfer points (such even if one bus is behind schedule. as a rail station or major transfer point). Layover locations are sensitive Ideally, the layover should occur at a location that allows the operator to safely leave the bus, because they require a location use the restroom, stretch his/her legs, and get away from the bus for a minute or two. Routes where a bus can "sit" safely for a period of time. with a one-way loop at one or both ends create challenges for identifying a layover location, since riders will be on the bus throughout the loop and some passengers will experience a de- lay. Layover time may also be assigned at key mid-route transfer points (such as a rail station interlining or major transfer point). The use of the same vehicle on a block operating on more than one Interlining and Through-routing route with the same operator, with- Sometimes, trips that come into the end of the line are not simply sent back out on the same out returning to the garage during route but can be "interlined" or hooked to other routes serving that terminal or another route changes. nearby location. Interlining is most often done to optimize blocking, although it can be a con- venience to passengers. school trips or school service For example, if many passenger trips originating on one route are destined for locations along a second route that shares a common terminal location, interlining will allow those passengers Additional scheduled trips at to reach their destination without transferring to another vehicle. At some systems, such activ- school bell times to accommodate ity is the precursor to merging the two routes into one. the heavy loads associated with student ridership along a route. Another application of interlining is to match up school trips in the afternoon with trips at the School trips are typically inserted start of evening peak trips. Such matching is invaluable for saving PM pull-outs. The process is into the schedule for no longer than usually not applied in the AM because of the overlap of school service with AM peak service. necessary to address ridership de- Bus savings are always a priority, but interlining is also highly useful for saving bus hours, which mand. As with other service, these ultimately saves platform costs and even operators. trips are open to the public and are included on public timetables. 4-6

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Level . The Basics Chapter 4. Schedule Blocking While it might be tempt- Tip In a radial transit network with timed meets at the central locations, interlining long routes that ing to minimize layover are tight for time with shorter routes where layover is plentiful is an excellent strategy. In this in all cases, remember that layover case, interlining guards against the domino effect of a long route arriving later and later each serves an important purpose--it hour. It also ensures adequate layover time for each operator, an important factor in operator- is designed to get trips to start on friendly assignments. time and can be one of the most important factors in reliability. Vehicles may travel between one route and another only once or only occasionally throughout the day. For example, a PM pull-out may first do a school-related trip on Route X and then op- erate on Route Y. Another case might involve a vehicle providing morning peak service on one route and then operating on another route in the midday period. through-routing It is also possible for a vehicle to alternate trips between two or more routes throughout the A form of interlining in which a day. If only two routes are involved, this form of regular interlining is often referred to as vehicle switches from inbound "through-routing." "Interlining" and "through-routing" tend to be used interchangeably, but service on one route to outbound through-routing is the process of tying together routes, especially radial routes which serve service on another route while a central downtown location, to form one long route from one end of town to another via continuing in service throughout the downtown. Each trip throughout the day arrives as Route A and leaves as Route B. Both routes day. may even carry the same route number. Through-routing can reduce the number of buses by eliminating any duplication of two unconnected routes that would otherwise terminate down- town, provide through passengers with a one-seat ride, reduce the need for layover space, and simplify routing by reducing the number of turns required. The amount of interlining at any transit property is often a matter of policy. One of the transit systems that served as a case study makes it a policy to interline as much service as possible. The agency's interest is for drivers to work as many routes as possible during their run. It helps make the day more interesting, familiarizes the drivers with more of the system, and at the same time saves enough buses to make the more complex blocking arrangement worth the extra time it takes to set up. 4-7

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Chapter 4. Schedule Blocking Level . The Basics Basic Blocking Exercise With an understanding of the basic concepts of blocking, we are ready to block Route . The master schedule for Route was developed in the basic section of the previous chapter on schedule building, and is shown below. The schedule provides service every minutes from the first eastbound trip at : AM to the last westbound trip at : PM. Running times are consistent (i.e., do not change) throughout the day. C D E F G H I J K 1 Master Schedule for Route 97 2 ROUTE 97 Broad Street 3 DAY Weekday 4 Eastbound Westbound 5 A B C D D C B A 6 6:15 6:26 6:40 6:48 7 6:00 6:08 6:22 6:33 6:45 6:56 7:10 7:18 8 6:30 6:38 6:52 7:03 7:15 7:26 7:40 7:48 9 7:00 7:08 7:22 7:33 7:45 7:56 8:10 8:18 10 7:30 7:38 7:52 8:03 8:15 8:26 8:40 8:48 11 8:00 8:08 8:22 8:33 8:45 8:56 9:10 9:18 12 8:30 8:38 8:52 9:03 9:15 9:26 9:40 9:48 13 9:00 9:08 9:22 9:33 9:45 9:56 10:10 10:18 14 9:30 9:38 9:52 10:03 10:15 10:26 10:40 10:48 15 10:00 10:08 10:22 10:33 10:45 10:56 11:10 11:18 16 10:30 10:38 10:52 11:03 11:15 11:26 11:40 11:48 17 11:00 11:08 11:22 11:33 11:45 11:56 12:10 12:18 18 11:30 11:38 11:52 12:03 12:15 12:26 12:40 12:48 19 12:00 12:08 12:22 12:33 12:45 12:56 13:10 13:18 20 12:30 12:38 12:52 13:03 13:15 13:26 13:40 13:48 21 13:00 13:08 13:22 13:33 13:45 13:56 14:10 14:18 22 13:30 13:38 13:52 14:03 14:15 14:26 14:40 14:48 23 14:00 14:08 14:22 14:33 14:45 14:56 15:10 15:18 24 14:30 14:38 14:52 15:03 15:15 15:26 15:40 15:48 25 15:00 15:08 15:22 15:33 15:45 15:56 16:10 16:18 26 15:30 15:38 15:52 16:03 16:15 16:26 16:40 16:48 27 16:00 16:08 16:22 16:33 16:45 16:56 17:10 17:18 28 16:30 16:38 16:52 17:03 17:15 17:26 17:40 17:48 29 17:00 17:08 17:22 17:33 17:45 17:56 18:10 18:18 30 17:30 17:38 17:52 18:03 18:15 18:26 18:40 18:48 31 18:00 18:08 18:22 18:33 18:45 18:56 19:10 19:18 32 18:30 18:38 18:52 19:03 19:15 19:26 19:40 19:48 33 19:00 19:08 19:22 19:33 4-8

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Level . The Basics Chapter 4. Schedule Blocking Applicable work rules include the following: The minimum layover time is % of round-trip running time. Layover time may be taken at either terminal and may be divided in any way between the two terminals as long as the total layover time for any round trip is at least % of round-trip running time. No interlining will take place, because only one route is being blocked in this example. No other work rules apply. blocking sheet A blocking sheet is often used to track blocks as they are created. A sample blocking sheet is A sheet listing all blocks that also shown below. includes the trips and times for all trips within each block. Blocking Sheet ROUTE 97 Broad Street Special Instructions: DAY Weekday 24 minutes available for layover per round trip DATE Sep-08 OK to split between terminals Eastbound Westbound Depart Arrive Available Depart Arrive Available Western Eastern for next trip Eastern Western for next trip Block # Pull Out Trip # Terminal Terminal (arrival + Trip # Terminal Terminal (arrival + Pull In A D layover) D A layover) 4-9

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Chapter 4. Schedule Blocking Level . The Basics Pull-out refers to the time that a vehicle is scheduled to leave the garage or depot and travel to pull-out time the point on the route where revenue service begins. Pull-in refers to the time that the vehicle The time the vehicle spends traveling is scheduled to arrive at the garage/depot after completing revenue service. For Route , pull- from the garage to the route. Pull-out out times are listed in the Pull-out and Pull-in Allowance table shown below. time is included in vehicle hours, but not in revenue hours. Collectively, Route Pull-out and Pull-in Allowances pull-in time and pull-out time are Terminal Pull-out Pull-in also known as pull time and are A Weekday: : Weekday: : components of deadhead miles. Sat/Sun: no service Sat/Sun: no service B Weekday: : Weekday: : Sat/Sun: no service Sat/Sun: no service Layover time is almost Tip Our work rules require a minimum layover time of % of the total round-trip running always rounded up to the time. The running time is minutes in each direction, or minutes for a round trip. Thus, nearest minute. x % = . , rounded up to minutes of layover time. Recall in Chapter that we decided on a -minute headway, resulting in minutes of layover time per round trip. So, there should be no problem meeting minimum layover requirements. Blocks must always One final note before we get down to work relates to block numbering conventions. Transit Tip include a pull-out time agencies use a variety of numbering conventions for blocks. One of the most common is to use (the time the bus is scheduled to a four-digit number, where the first two digits are the route number and the second two digits leave the garage) and a pull-in time are the block number. This guarantees that each block will have a unique block number. For (the time the bus should arrive back Route , the first block number would be . at the garage). Different systems have their own style of numbering blocks. Some like to go in strict time out The amount of time required to order, while others prefer to keep block numbers in order during the day. The concept of the travel from the garage to the route block number serves two purposes: ( ) to keep track of the blocks while building the schedule and to return to the garage will vary and constructing runs and ( ) to inform on-street supervision of the positive identification of a by route and terminal. particular trip (not always obvious on a route with a -minute or better headway). Because of the latter, many prefer numbering blocks in order, and this will be the convention we follow for Route . The Blocking Process for Route 97 The first trip on the master schedule sheet is eastbound at : AM. The pull-in and pull-out al- lowance table indicates that the pull-out time to point A is minutes, so the first block, , pulls out from the garage at : AM and travels without passengers (deadheads) to the west- ern terminal at A in time to begin service at : AM. Block arrives at the eastern terminal (D) at : . The next available westbound trip is at : , allowing minutes of layover time at 4-10

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Level . The Basics Chapter 4. Schedule Blocking pull-in time D. This trip reaches A at : and, after minutes of layover, can make its next eastbound trip The time the vehicle spends at : . traveling from the route to the Note below on the master schedule worksheet that we have inserted two columns to the left of garage. Pull-in time is included in Point A for the block number and the pull-out time. We have added two columns on the right, vehicle hours, but not in revenue listing the next trip time leaving Point A and the pull-in time. We have also lined up the trips hours. Collectively, pull-in time and pull-out time are also known arriving and departing at Point D so that the round trip for a given block is in the same row. This as pull time and are components of helps in following the progress of a block throughout the day, as does listing the next trip time deadhead miles. on the right-hand side. We have entered all the information noted above in this spreadsheet. A B C D E F G H I J K L M N 1 Master Schedule for Route 97 2 ROUTE 97 Broad Street 3 DAY Weekday 4 Eastbound Westbound 5 Block # Pull Out A B C D D C B A Next Trip Pull In 6 6:15 6:26 6:40 6:48 7 9701 5:50 6:00 6:08 6:22 6:33 6:45 6:56 7:10 7:18 7:30 8 6:30 6:38 6:52 7:03 7:15 7:26 7:40 7:48 9 7:00 7:08 7:22 7:33 7:45 7:56 8:10 8:18 10 7:30 7:38 7:52 8:03 8:15 8:26 8:40 8:48 11 8:00 8:08 8:22 8:33 8:45 8:56 9:10 9:18 12 8:30 8:38 8:52 9:03 9:15 9:26 9:40 9:48 It is helpful to track the trip numbers for each block on either a copy of the master schedule or on the blocking sheet. Below are the entries on the blocking sheet for the pull-out and the first trips. Blocking Sheet ROUTE 97 Broad Street Special Instructions: DAY Weekday 24 minutes available for layover per round trip DATE Sep-08 OK to split between terminals Eastbound Westbound Depart Arrive Available Depart Arrive Available Western Eastern for next trip Eastern Western for next trip Block # Pull Out Trip # Terminal Terminal (arrival + Trip # Terminal Terminal (arrival + Pull In A D layover) D A layover) 9701 5:50 01 6:00 6:33 6:45 02 6:45 7:18 7:30 4-11

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Chapter 4. Schedule Blocking Level . The Basics The blocking process continues by hooking more trips on to . Use of color coding on spreadsheets to follow a block through the day is extremely helpful. Since this example is in black and white, we will simply indicate the block number and next trip on the spreadsheet. We show the next two round trips for block below. A B C D E F G H I J K L M N 1 Master Schedule for Route 97 2 ROUTE 97 Broad Street 3 DAY Weekday 4 Eastbound Westbound 5 Block # Pull Out A B C D D C B A Next Trip Pull In 6 6:15 6:26 6:40 6:48 7 9701 5:50 6:00 6:08 6:22 6:33 6:45 6:56 7:10 7:18 7:30 8 6:30 6:38 6:52 7:03 7:15 7:26 7:40 7:48 9 7:00 7:08 7:22 7:33 7:45 7:56 8:10 8:18 10 9701 7:30 7:38 7:52 8:03 8:15 8:26 8:40 8:48 9:00 11 8:00 8:08 8:22 8:33 8:45 8:56 9:10 9:18 12 8:30 8:38 8:52 9:03 9:15 9:26 9:40 9:48 13 9701 9:00 9:08 9:22 9:33 9:45 9:56 10:10 10:18 10:30 Block makes the : eastbound trip and the : westbound trip. The next available trip at A when it arrives at : is the : trip. So we note that block will make this trip and the return trip westbound at : . 4-12

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Level . The Basics Chapter 4. Schedule Blocking travel time Now continue this process of hooking trips for the remainder of the day. Your spreadsheet will Paid time allowed for an operator to look like this: travel between the garage and a re- lief location. If the travel is for relief A B C D E F G H I J K L M N purposes only and is not part of a 1 Master Schedule for Route 97 pull-in or pull-out, then travel time is 2 ROUTE 97 Broad Street not included in platform time. 3 DAY Weekday 4 Eastbound Westbound 5 Block # Pull Out A B C D D C B A Next Trip Pull In 6 6:15 6:26 6:40 6:48 7 9701 5:50 6:00 6:08 6:22 6:33 6:45 6:56 7:10 7:18 7:30 8 6:30 6:38 6:52 7:03 7:15 7:26 7:40 7:48 9 7:00 7:08 7:22 7:33 7:45 7:56 8:10 8:18 10 9701 7:30 7:38 7:52 8:03 8:15 8:26 8:40 8:48 9:00 11 8:00 8:08 8:22 8:33 8:45 8:56 9:10 9:18 12 8:30 8:38 8:52 9:03 9:15 9:26 9:40 9:48 13 9701 9:00 9:08 9:22 9:33 9:45 9:56 10:10 10:18 10:30 14 9:30 9:38 9:52 10:03 10:15 10:26 10:40 10:48 15 10:00 10:08 10:22 10:33 10:45 10:56 11:10 11:18 16 9701 10:30 10:38 10:52 11:03 11:15 11:26 11:40 11:48 12:00 17 11:00 11:08 11:22 11:33 11:45 11:56 12:10 12:18 18 11:30 11:38 11:52 12:03 12:15 12:26 12:40 12:48 19 9701 12:00 12:08 12:22 12:33 12:45 12:56 13:10 13:18 13:30 20 12:30 12:38 12:52 13:03 13:15 13:26 13:40 13:48 21 13:00 13:08 13:22 13:33 13:45 13:56 14:10 14:18 22 9701 13:30 13:38 13:52 14:03 14:15 14:26 14:40 14:48 15:00 23 14:00 14:08 14:22 14:33 14:45 14:56 15:10 15:18 24 14:30 14:38 14:52 15:03 15:15 15:26 15:40 15:48 25 9701 15:00 15:08 15:22 15:33 15:45 15:56 16:10 16:18 16:30 26 15:30 15:38 15:52 16:03 16:15 16:26 16:40 16:48 27 16:00 16:08 16:22 16:33 16:45 16:56 17:10 17:18 28 9701 16:30 16:38 16:52 17:03 17:15 17:26 17:40 17:48 18:00 29 17:00 17:08 17:22 17:33 17:45 17:56 18:10 18:18 30 17:30 17:38 17:52 18:03 18:15 18:26 18:40 18:48 31 9701 18:00 18:08 18:22 18:33 18:45 18:56 19:10 19:18 19:28 32 18:30 18:38 18:52 19:03 19:15 19:26 19:40 19:48 33 19:00 19:08 19:22 19:33 Note that when completes the : westbound trip at : , it has no trip to hook to and so it is time to return to the garage. The pull-out and pull-in allowance sheet indicates min- utes of travel time from point A to the garage, so the pull-in time will be : + : = : . 4-13

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Chapter 4. Schedule Blocking Level . The Basics The blocking sheet now summarizes the information for all trips on block and looks like this: Blocking Sheet ROUTE 97 Broad Street Special Instructions: DAY Weekday 24 minutes available for layover per round trip DATE Sep-08 OK to split between terminals Eastbound Westbound Depart Arrive Available Depart Arrive Available Western Eastern for next trip Eastern Western for next trip Block # Pull Out Trip # Terminal Terminal (arrival + Trip # Terminal Terminal (arrival + Pull In A D layover) D A layover) 9701 5:50 01 6:00 6:33 6:45 02 6:45 7:18 7:30 9701 03 7:30 8:03 8:15 04 8:15 8:48 9:00 9701 05 9:00 9:33 9:45 06 9:45 10:18 10:30 9701 07 10:30 11:03 11:15 08 11:15 11:48 12:00 9701 09 12:00 12:33 12:45 10 12:45 13:18 13:30 9701 11 13:30 14:03 14:15 12 14:15 14:48 15:00 9701 13 15:00 15:33 15:45 14 15:45 16:18 16:30 9701 15 16:30 17:03 17:15 16 17:15 17:48 18:00 9701 17 18:00 18:33 18:45 18 18:45 19:18 19:28 Next, we add Block . As noted earlier in the discussion of block numbering, we will keep the blocks in numerical order throughout the day, so Block should always follow . Its first trip will thus be eastbound at : , requiring a pull-out time of : . The example below shows the first few trips of filled in on the spreadsheet. A B C D E F G H I J K L M N 1 Master Schedule for Route 97 2 ROUTE 97 Broad Street 3 DAY Weekday 4 Eastbound Westbound 5 Block # Pull Out A B C D D C B A Next Trip Pull In 6 6:15 6:26 6:40 6:48 7 9701 5:50 6:00 6:08 6:22 6:33 6:45 6:56 7:10 7:18 7:30 8 9702 6:20 6:30 6:38 6:52 7:03 7:15 7:26 7:40 7:48 8:00 9 7:00 7:08 7:22 7:33 7:45 7:56 8:10 8:18 10 9701 7:30 7:38 7:52 8:03 8:15 8:26 8:40 8:48 9:00 11 9702 8:00 8:08 8:22 8:33 8:45 8:56 9:10 9:18 9:30 12 8:30 8:38 8:52 9:03 9:15 9:26 9:40 9:48 13 9701 9:00 9:08 9:22 9:33 9:45 9:56 10:10 10:18 10:30 14 9702 9:30 9:38 9:52 10:03 10:15 10:26 10:40 10:48 11:00 4-14

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Level . The Basics Chapter 4. Schedule Blocking We continue throughout the day until its pull-in time at : . Then we add block . Note that this block pulls out to D, not A, so we need to check our allowance table. Instead of the minutes of pull-out time to point A, requires minutes to point D, so pull-out time is minutes earlier than : , or : . The pull-in is also from D, not A, and requires min- utes. The pull-in time for is : , as shown in the completed blocked schedule below. A B C D E F G H I J K L M N 1 Master Schedule for Route 97 2 ROUTE 97 Broad Street 3 DAY Weekday 4 Eastbound Westbound 5 Block # Pull Out A B C D D C B A Next Trip Pull In 6 9703 5:55 6:15 6:26 6:40 6:48 7:00 7 9701 5:50 6:00 6:08 6:22 6:33 6:45 6:56 7:10 7:18 7:30 8 9702 6:20 6:30 6:38 6:52 7:03 7:15 7:26 7:40 7:48 8:00 9 9703 7:00 7:08 7:22 7:33 7:45 7:56 8:10 8:18 8:30 10 9701 7:30 7:38 7:52 8:03 8:15 8:26 8:40 8:48 9:00 11 9702 8:00 8:08 8:22 8:33 8:45 8:56 9:10 9:18 9:30 12 9703 8:30 8:38 8:52 9:03 9:15 9:26 9:40 9:48 10:00 13 9701 9:00 9:08 9:22 9:33 9:45 9:56 10:10 10:18 10:30 14 9702 9:30 9:38 9:52 10:03 10:15 10:26 10:40 10:48 11:00 15 9703 10:00 10:08 10:22 10:33 10:45 10:56 11:10 11:18 11:30 16 9701 10:30 10:38 10:52 11:03 11:15 11:26 11:40 11:48 12:00 17 9702 11:00 11:08 11:22 11:33 11:45 11:56 12:10 12:18 12:30 18 9703 11:30 11:38 11:52 12:03 12:15 12:26 12:40 12:48 13:00 19 9701 12:00 12:08 12:22 12:33 12:45 12:56 13:10 13:18 13:30 20 9702 12:30 12:38 12:52 13:03 13:15 13:26 13:40 13:48 14:00 21 9703 13:00 13:08 13:22 13:33 13:45 13:56 14:10 14:18 14:30 22 9701 13:30 13:38 13:52 14:03 14:15 14:26 14:40 14:48 15:00 23 9702 14:00 14:08 14:22 14:33 14:45 14:56 15:10 15:18 15:30 24 9703 14:30 14:38 14:52 15:03 15:15 15:26 15:40 15:48 16:00 25 9701 15:00 15:08 15:22 15:33 15:45 15:56 16:10 16:18 16:30 26 9702 15:30 15:38 15:52 16:03 16:15 16:26 16:40 16:48 17:00 27 9703 16:00 16:08 16:22 16:33 16:45 16:56 17:10 17:18 17:30 28 9701 16:30 16:38 16:52 17:03 17:15 17:26 17:40 17:48 18:00 29 9702 17:00 17:08 17:22 17:33 17:45 17:56 18:10 18:18 18:30 30 9703 17:30 17:38 17:52 18:03 18:15 18:26 18:40 18:48 19:00 31 9701 18:00 18:08 18:22 18:33 18:45 18:56 19:10 19:18 19:28 32 9702 18:30 18:38 18:52 19:03 19:15 19:26 19:40 19:48 19:58 33 9703 19:00 19:08 19:22 19:33 19:53 4-15

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Chapter 4. Schedule Blocking Level . The Basics The completed blocking sheet is shown below. Blocking Sheet ROUTE 97 Broad Street Special Instructions: DAY Weekday 24 minutes available for layover per round trip DATE Sep-08 OK to split between terminals Eastbound Westbound Depart Arrive Available Depart Arrive Available Western Eastern for next trip Eastern Western for next trip Block # Pull Out Trip # Terminal Terminal (arrival + Trip # Terminal Terminal (arrival + Pull In A D layover) D A layover) 9701 5:50 01 6:00 6:33 6:45 02 6:45 7:18 7:30 9701 03 7:30 8:03 8:15 04 8:15 8:48 9:00 9701 05 9:00 9:33 9:45 06 9:45 10:18 10:30 9701 07 10:30 11:03 11:15 08 11:15 11:48 12:00 9701 09 12:00 12:33 12:45 10 12:45 13:18 13:30 9701 11 13:30 14:03 14:15 12 14:15 14:48 15:00 9701 13 15:00 15:33 15:45 14 15:45 16:18 16:30 9701 15 16:30 17:03 17:15 16 17:15 17:48 18:00 9701 17 18:00 18:33 18:45 18 18:45 19:18 19:28 9702 6:20 01 6:30 7:03 7:15 02 7:15 7:48 8:00 9702 03 8:00 8:33 8:45 04 8:45 9:18 9:30 9702 05 9:30 10:03 10:15 06 10:15 10:48 11:00 9702 07 11:00 11:33 11:45 08 11:45 12:18 12:30 9702 09 12:30 13:03 13:15 10 13:15 13:48 14:00 9702 11 14:00 14:33 14:45 12 14:45 15:18 15:30 9702 13 15:30 16:03 16:15 14 16:15 16:48 17:00 9702 15 17:00 17:33 17:45 16 17:45 18:18 18:30 9702 17 18:30 19:03 19:15 18 19:15 19:48 19:58 9703 5:55 01 6:15 6:48 7:00 9703 02 7:00 7:33 7:45 03 7:45 8:18 8:30 9703 04 8:30 9:03 9:15 05 9:15 9:48 10:00 9703 06 10:00 10:33 10:45 07 10:45 11:18 11:30 9703 08 11:30 12:03 12:15 09 12:15 12:48 13:00 9703 10 13:00 13:33 13:45 11 13:45 14:18 14:30 9703 12 14:30 15:03 15:15 13 15:15 15:48 16:00 9703 14 16:00 16:33 16:45 15 16:45 17:18 17:30 9703 16 17:30 18:03 18:15 17 18:15 18:48 19:00 9703 18 19:00 19:33 19:53 4-16

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Level . The Basics Chapter 4. Schedule Blocking Now that we have been through the basic blocking process, questions such as the following may arise. How is layover time related to costs? Excessive layover time increases the number of vehicles and operators required on a given route. Recall that we calculate the number of vehicles required using the following formula: Cycle time # Vehicles = Headway where cycle time equals the round-trip running time plus layover time and headway is the time between trips. For example, if a route has a round-trip running time of minutes plus minutes for layover and a headway of minutes, then the formula shows a need for vehicles: ( + )= # Vehicles = = However, if the layover time is increased to minutes, then the number of vehicles needed also increases: ( + )= # Vehicles = = Obviously, a layover of minutes versus minutes is more economical in terms of fewer ve- hicles and, most likely, fewer operators. Is there any benefit to having slightly excessive layover time? As noted in Chapter (Schedule Building), extra layover time may be assigned when clockface headways are desired, as in the Route example. Also, timed transfers sometimes result in the need for extra layover time to ensure that passengers on trips arriving a few minutes be- hind schedule can still make their connections. Schedule building and blocking often involve a balancing of cost-effectiveness and customer service needs. In cases where excessive layover time does exist after a trip, it may be possible to hook this trip with another trip. These are opportunities that schedulers continually evaluate. 4-17

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Chapter 4. Schedule Blocking Level . The Basics Do many schedules maintain a consistent headway throughout the day? pull-in miles Busy routes on major travel corridors typically have shorter headways (i.e., more frequent ser- The distance the vehicle travels vice) in the peak hours. Routes serving less busy areas are more likely to maintain a consistent from the route to the garage. Pull- headway throughout the day. Even on these routes, however, the last trip or two of the day is out miles are included in vehicle often inconsistent for a variety of reasons. One important reason to delay the start time of the miles, but not in revenue miles. last trips on a route is to allow the maximum number of passengers to catch the final trip(s). Collectively, pull-in miles and The last trip of the day often functions as a safety net for passengers working late, staying after pull-out miles are also known as at school, or delayed for some other reason. pull miles and are components of deadhead miles. In the example of Route 97, two blocks begin at the western terminal (A) and one begins at the eastern terminal (D). Why don't they all begin at the same place, especially since A is only 10 min- pull-out miles utes from the garage while D is 20 minutes away? The distance the vehicle Once the decision regarding the time to begin service in both directions is made, the blocking travels from the garage to the process is intended to place the vehicles where they need to be. In the previous chapter, the route. Pull-in miles are included in decision was made to begin eastbound service at : AM and westbound service at : AM. vehicle miles, but not in revenue In this simple example, the only way to do this is to pull out Block to D. In the intermedi- miles. Collectively, pull-in miles and ate and advanced sections below, we will discuss other blocking strategies regarding pull-out, pull-out miles are also known as such as beginning a trip mid-route and minimizing deadhead time by pulling out a block into pull miles and are components of revenue service as soon as possible. deadhead miles. Do the same principles regarding blocking apply in more complex cases where more than one route is involved? The short answer is yes, as you will see in the intermediate and advanced sections. An expand- ed blocking exercise would include all trips operated from the same garage. Obviously, as the task gets more complex, the ability to perform blocking by hand becomes more difficult and the use of computer software grows more advisable. "Tedious" scheduling tasks used to be a bane of schedulers. Computers have relieved us of most of these. Chief among them are by-hand blocking (the writing the numbers in part, not the strategizing) and calculating mileage. Calculating hours is not the most interesting task, but at least you do not have to keep track of every minor deadhead and service pattern and the number of times they are used. This is truly a routine that computers were built for. But when you are starting out, these tasks give you a "feel" for all the elements that go into a schedule. Doing them also gives you a sense of accomplishment and the knowledge that everything on the schedule is accounted for. That said, we encourage you to travel all of these "long paths." What you learn along the way will be invaluable as you progress as a seasoned scheduler. The specific process or commands for blocking our trips in a computerized system vary be- tween systems. But almost certainly you will have the option to have the system automatically 4-18

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Level . The Basics Chapter 4. Schedule Blocking vehicle hours block your trips and provide the result, or allow you to work through and manually hook the Total hours of travel by a vehicle, trips. In the Route example, the result is guaranteed to be the same as we meet any pre- including hours in revenue service scribed layover requirements, and the schedule is simple (presenting the system with few or no (including layover time) and alternative hooking options). deadhead travel. Calculating Vehicle Statistics revenue hours Now that our spreadsheet has been populated with trips and block information we have all the components we need to build summaries of hours, vehicles, and mileage. Typically the key ele- The number of hours of service ments needed in a summary table will include: available to passengers for trans- port on the routes. Excludes Vehicle Hours: Comprised of revenue hours (including layover time) plus pull-in and deadhead hours, but includes pull-out time layover time. Calculated for each Vehicle Miles: Comprised of revenue miles plus pull-in and pull-out miles route and for the system as a whole. Depending on the spreadsheet's level of sophistication, these can be calculated automatically, or as fixed formulas. Either way the spreadsheet tools can be used to calculate these numbers. vehicle miles The method of calculating can be as automated as you require or are capable of developing. Total miles of travel by a vehicle, The method used in our spreadsheet is to have a set of "fixed" parameters: running times and including hours in revenue service distances eastbound and westbound, pull out times, and mileage to "A" and "D." and deadhead travel. A simple method of estimating mileage would then be to multiply (using a count function) the revenue miles number of trips by mileage for that direction. The same can be done for hours, or alternatively The number of miles of service could be a sum of subtracting the trip arrivals from trip departures. A typical vehicle statistics available to passengers for trans- summary called a block summary table may look like the following: port on the routes. Excludes T U V W X Y deadhead miles. Calculated for 1 each route and for the system as a 2 3 whole. 4 Hours Summary 5 Block Garage Depart Garage Arrive Platform Hours 6 1 5:50 19:28 13:38 block summary table 7 2 6:20 19:58 13:38 8 3 5:55 19:53 13:58 Summary of vehicle statistics, 9 Total 41:14 including platform hours and 10 11 mileage, by block. 12 Mileage Summary 13 Block Eastbound Trips Westbound Trips Pull Trips - "A" Pull Trips - "D" Mileage 14 1 9 9 2 0 124.0 15 2 9 9 2 124.0 16 3 9 9 0 2 130.6 17 Total 27 27 4 2 378.6 4-19

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Chapter 4. Schedule Blocking Level . The Basics For computerized scheduling packages once the blocks have been created, and pulls com- Use your blocks to pleted, the costing function will be able to provide the necessary information automatically, Tip estimate your operator according to your agency's requirements. needs. At this point you are able to roughly estimate the number of additional bus operators you will Total platform time = # operators needed Average platform time need for this schedule simply by dividing the total platform hours by the average platform time in your runs. This example yields : hours, which would produce five runs of slightly over This is only a rough estimate, but it : in duration each. That is a good figure to use for estimates, even though the actual runcut will be a useful check on the runcut. will probably produce somewhat different individual results. The most practical aspect of this finished schedule is that you now have detailed statistics with which to develop costs for implementing this service. Your finance group should have figures block graph on system costs on a per-hour and per-mile basis which can be applied against the figures in A graphical representation of all your Hours and Miles table. If your schedule has met the budget goal, you know it positively at blocks assigned to a garage that this point. If not, you can take steps to reduce the service by cutting back trips, taking a bus out must be considered in the runcut of the cycle, or shortening the route--all actions discussed in the intermediate and advanced solution. The graph includes, at a sections of Chapter (Schedule Building). These costs are still an estimate at this point; until minimum, the start and end times you cut the runs (see Chapter ), you will not have pay hours for operators. of each block, and may also include terminal times and all eligible relief Graphing the Blocks times. Understanding the number Blocks are often displayed graphically to illustrate the time spans that the blocks are in service. and duration of all blocks is an Time spans (in this case, platform time) can be obtained from the vehicle statistics. important requisite in reaching an optimal runcut solution. An example of a graphic display of Route is shown below. This type of graphic display is es- pecially valuable as a tool for runcutting in the absence of a computerized scheduling software package. Computerized packages can generate these graphs automatically. Block 5A 6A 7A 8A 9A 10A 11A 12P 1P 2P 3P 4P 5P 6P 7P 8P 550 1928 9701 620 1958 9702 555 1953 9703 4-20

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Level . The Basics Chapter 4. Schedule Blocking LEVEL End of Basic Blocking. 1 The Intermediate Section of Blocking continues on the next page. To jump to Runcutting, go to page - . 4-21