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Level . Building a Simple Schedule Chapter 3. Schedule Building 3.1 Building a Simple Schedule span of service Even a simple schedule reveals some important concepts that apply in one way or The length of time, from the begin- LEVEL another to all scheduling. In fact, the most complicated schedule is no more than ning of the first trip to the end of the last trip, during which service 1 a series of the same steps we will talk about here. operates on the street. Can be Do not be misled by our calling this a "simple" schedule. Sometimes the most dif- expressed for a route or for the ficult schedules are those with the fewest options (i.e., the "simple" ones!). In reality, schedul- system as a whole. ing only becomes simple by doing it over and over again. headway For this project we will build a straightforward -minute all-day schedule on a single route The interval of time between two that operates just one service pattern. Let's call this Route --Broad St.--a new route being vehicles running in the same direc- developed. We are just interested in the weekday schedule for now. tion on the same route, usually Here is what you need to know: expressed in minutes. See also "frequency." Span of Service : AM to : PM Headway minutes throughout service pattern Service patterns All trips operated from time point A to time point D. Reverse direc- The unique sequence of stops tion trips from D to A associated with each type of trip on a route. If all trips operate from Garage This route operates out of Park Garage which is nearer to the time point A end one end to the other on a common of the route path the route has one service pat- Deadhead times to and from the garage are: minutes to/from "A," minutes to/ tern. Branches, deviations, or short from "D" turns introduce additional service Mileage and running time shown in the diagram below patterns. Service patterns are a fundamental component of schedul- A B C D ing and provide the framework for 8 min 14 min 11 min tracking running time, generating revenue trips, and identifying dead- head movements for the route. 1.38 min . miles 2.87 min . miles 2.22 min . miles deadhead The upper numbers are minutes between time points, the lower is the mileage. The time and distance that a bus needs to travel in places where it will not pick up passengers. Deadheading is typically required to get buses to and from their garage, or need to travel from one route or point to another during their sched- uled work day. 3-3

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Chapter 3. Schedule Building Level . Building a Simple Schedule Most of this information will come from a service plan or from discussion with planners. It will cycle time always be up to you to verify this information, because ultimately the responsibility for the Sum of the round-trip running time development of the operating schedule falls to you. plus layover time. Also known as "round trip cycle time." So, where to start? Here is the general sequence of events: . Calculate the round-trip cycle time, including layover. schedule pattern . Figure out how much layover you have and where to apply it. . Work out the basic schedule pattern. This is the key to the task and includes consider- A summary of the schedule in terms ation of: of running times between time points and layover time at termi- The cycle and layover times Operational preferences nals. The schedule pattern can be Contract layover requirements Runcut requirements repeated throughout the day or can . Decide where and when (based on the span of service standard discussed in Chapter ) change as running times and lay- to start service. over times change during the day. . Populate the schedule. . Then, and only then, fill in the intermediate times, working downward while constantly layover time checking adjacent running times. Time between the scheduled arrival . Block your schedule by following the first trip and its subsequent trips (hooks) all the and departure of a vehicle at a way to the end of the schedule, then filling in the rest of the block numbers in the same transit terminal. Often used inter- manner. This and subsequent steps are addressed in Chapter : Schedule Blocking. changeably with "recovery time," . Mark your pull-on and pull-off locations for each block, and apply the out or in time to although technically layover time is rest time for the operator between and from the garage. trips while recovery time is time . Build a table of your blocks, showing pull-out and pull-in times and resulting vehicle built into the schedule to ensure an hours. The table will add up at the bottom to the total vehicle hours for the schedule. on-time departure for the next trip. . Build a table of mileage along the same principle, yielding total mileage for the In this manual, layover and recov- schedule. ery are calculated together and the . Proofread your work before declaring the schedule finished and ready for the runcut. total time between trips is referred . If need be, hand the schedule back to the planning staff so they can see what their con- to as "layover." cept looks like when turned into reality. Let's tackle steps one through six, which are most integral in building a schedule. Steps seven through are discussed separately in Chapter : Schedule Blocking. 3-4

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Level . Building a Simple Schedule Chapter 3. Schedule Building pull-on location 1 Round-trip Cycle Time The place on a route where a This is the most important concept you will master in building a proper schedule. The round- vehicle begins revenue service. trip cycle time is: Round-trip running time + required layover pull-off location The place on a route where a Since the round-trip running time must be already calculated and accurate, it is crucial to this vehicle ends revenue service. formula. On routes where running times vary by time of day, this cycle must be calculated for different times of the day. This example uses the information we have been given for Route . Working across the diagram on page - from left to right (we will call this eastbound) we find pull-out time running of , and minutes, which add up to minutes. The same minutes apply west- The time the vehicle spends travel- bound. This gives us a -minute round-trip. To that, an adequate layover must be added. ing from the garage to the route. Pull-out time is included in vehicle 2 Layover Requirements hours, but not in revenue hours. Layover requirements will be explored in greater detail in the following sections. For now, we Collectively, pull-in time and pull-out will assume some basic principles. Possibly your union contract specifies a minimum layover time are also known as pull time either at one end of the route or for a full round-trip. If the union contract does not address and are components of deadhead layover, past practice may guide the allocation of layover time. An example of minimum lay- miles. over is % of the running time or six minutes per round-trip, whichever is greater. This route might need more than that, depending on propensity for traffic congestion, a high number of pull-in time wheelchair boardings, and other operational details that cannot be accurately predicted in the The time the vehicle spends travel- running time. If so, then you will want to add some minutes to that required by the contract or ing from the route to the garage. allocated by past practice. Pull-in time is included in vehicle In our example, % of would be seven minutes (always round up to the next minute if the hours, but not in revenue hours. percentage is a minimum)--which, added to the running time, would give us a round-trip cycle Collectively, pull-in time and pull-out of minutes. That is the minimum cycle we can operate. time are also known as pull time and are components of deadhead Now the tough part comes in. We have to divide the cycle by the intended headway for the time. period. In this case, we have a requirement for a -minute headway all day. Multiples of are , , , , etc. We just missed and we cannot squeeze the running time back to fit into that cycle. Reducing layover below the minimum or reducing running time below the calcu- lated requirement is taboo, especially once we have determined that we need every bit of the minutes. So we have to see what other options we have. Since the cycle time cannot be shortened, one option would be to extend the round-trip cycle to minutes, the next highest -minute multiple, requiring buses ( divided by ). That would give us a total of minutes of layover, or %--a wasteful amount, with the bus and its 3-5

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Chapter 3. Schedule Building Level . Building a Simple Schedule operator sitting idle one third of the time. But if we have a system set up on pulses at a transit Never reduce a mini- center or other meet point, this may be our only option. In fact, if we generally allow five min- Tip mum required layover utes of connection time in each direction at a mid-route transit center, this allowance would time or calculated running time to bring us back to minutes that would be available for end of line layover, or %--a more "squeeze" the cycle to better fit the reasonable number. headway. Another option is to look at a better service level. If we stay to a clockface headway, a -min- ute headway would be our next choice. Progressions of are , , , , , etc. An - minute cycle would provide minutes of layover and a better frequency, but it would require transit center one more bus to operate the schedule ( divided by ). Can we afford the extra all day bus? An area designed to be served by An extra bus translates to about extra bus hours for the day, every day. Would a -minute multiple routes. A transit center headway work in any connection strategy we might have? Finally, do we really need a -min- may be on-street or off-street, but ute headway in order to carry the expected ridership levels? If the answer to any of these ques- in either case stop locations are tions is "no," then this is not our option. established to facilitate passenger connections and safe vehicle move- One final option is to look at a non-clockface headway. In this case, a -minute headway with ment. In radial networks, transit three buses would give us a -minute cycle, which is just three minutes more than our so- centers were located in downtown called minimum cycle, which is just fine if we can tolerate a -minute headway. The resulting areas. With the emergence of hub- schedule is not easy to remember, but in this case it does have the advantage of providing two and-spoke networks, an agency extra round-trips during the operating day for the same number of buses and bus hours. While may utilize multiple transit centers clockface headways are nice, the reality is that most people will consult a timetable for any (or hubs). service that is less frequent than every minutes. One other possibility exists--which is to use the extra time available to extend the route and timetable increase coverage. This kind of route adjustment to fit the schedule is usually done when ini- A document containing route and tially planning and scheduling the route or when considering a route extension. This is a good time information produced for use example of why there has to be a working collaboration process between planners and sched- by riders. ulers. Route design should always seek to take advantage of scheduling efficiencies and, more importantly, avoid creating inefficiencies. Since our schedule is a simple one, with the same headway and running time all day, we only need to calculate one round-trip cycle and make one determination as to where to apply the layover. This strategy will work all day. We will see examples of schedules with lots of variations in the intermediate and advanced sections later in this chapter. 3-6

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Level . Building a Simple Schedule Chapter 3. Schedule Building Time point placement In this example, we have decided on the -minute headway using three buses. The excess Tip is important. You do not layover time is not desirable, but works to our advantage for a route that connects with other want these points too close together routes in our system at a mid-route timed transfer point. We will discuss timed transfer nor too far apart. They should be at schemes in a later section. major intersections or other major points along the route, as the public 3 Basic Schedule Pattern will look for exact times at these Most basic schedules are laid out either using spreadsheets or computerized systems. For this points on the printed timetable. A exercise we will assume a spreadsheet is being used. rule of thumb is that time points are ideally spaced between about 7 and There are some important issues to consider about spreadsheet design. These include: 15 minutes apart, or an average of Simplicity. Avoid getting too complex with presentation. Use basic colors. about 10 minutes between each one. Beyond the need to inform the Location of inputs and outputs. Think about who will look at the sheet, and how it will public of scheduled arrival times, be used. Should fixed inputs (running times, mileage, etc.) be hidden to the side, on a time points serve to help drivers separate sheet, or readily visible? "pace themselves" when driving the Use of formulas. We will state repeatedly throughout this manual the importance of route. The scheduler should also accuracy. Spreadsheets are terrific tools for minimizing repetitive work. They also pres- ensure that bus stops exist in both ent pitfalls, as errors can be difficult to find and/or trace. The key principle in design of a directions at a time point, to avoid headway sheet should be to use formulas as much as possible--if you can avoid typing a confusing the riding public. number that can be calculated, do so! Why? There are two main reasons. First, the need to avoid errors, which are more likely to occur through manually typing numbers. Secondly, schedules inevitably change (you will see an example shortly). The more automated a sheet is, the easier (and less prone to error) the change process will be. If you want to highlight things, consider use of conditional formatting. As you will see on the sample spreadsheet, there are only two typed values. The rest are formulas. 3-7

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Chapter 3. Schedule Building Level . Building a Simple Schedule In laying out the schedule, it is a lot easier to have the two directions placed side by side. You master schedule can see the flow of the schedule better that way, although it does take some prior planning on A document that displays all time how you lay out the sheet. points and trips on a route. Usu- ally includes run numbers, block Start preparing the headway sheet or master schedule by naming the columns across the numbers, and pull-in and pull-out top. Start with the Eastbound direction first (that is our preference, but it can work to start times. Used interchangeably in this with westbound first if you have a compelling reason to do so...or just favor doing it that way). manual with "headway sheet." Column A is for the block number. Here is where we will keep track of the bus rotation in the schedule. Column B is for Pull-Out times or the time the bus leaves the garage. Columns C through F are time points by name, in our case A, B, C, and D. Leave Column G blank and start block back westbound with time points D, C, B, and A. Then leave Column L blank and label Column A vehicle (or train) assignment that M Next Trip. Column M is where you will keep track of hooking round-trips to their next trips includes the series of trips oper- or, when running out of trips, will indicate by a blank that they become a pull-in. Follow that ated by each vehicle from the time with Column N for Pull-in. Your spreadsheet will look like this: it pulls out to the time it pulls in. A complete block includes a pull-out trip from the garage followed by one A B C D E F G H I J K L M N or (usually) more revenue trips and 1 Example Headway Sheet #1 2 ROUTE 97 Broad Street concluding with a pull-in trip back to 3 DAY Weekday the garage. 4 Eastbound Westbound 5 Block # Pull Out A B C D D C B A Next Trip Pull In hooking The process of attaching the end of A quick note about the term "block." This is the term for the vehicle (bus, light rail vehicle or a trip in one direction to the begin- train, heavy rail train, etc.) assignment, which describes what the vehicle will do in a day. Some ning of a trip the other direction. A systems call this a "train" or a "run" or even a "key." We use "block" because that is the prevail- block is a series of hooked trips. ing term in the industry and is less likely to be confused with "run," which is predominantly applied to the driver, not the vehicle, assignment. round-trip A trip that travels along a route and then returns to its original starting point; a combination of two one-way trips on a route. 3-8

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Level . Building a Simple Schedule Chapter 3. Schedule Building Note that we enter vari- Tip We start by noting down some basic information--the P Q R ous clock face headway running time and distance between time points in each 1 options in time format in cells Q30: direction and the headway, for starters. We will put this 2 Q36. These will remain the same out of the way, to the right of the schedule, in columns 3 no matter how many times we use P through R, as shown here. We also add in time and 4 Running Time/Mileage Definitions this spreadsheet, and the time for- mileage from the garage to the two end points of the 5 6 Eastbound mat saves a step in entering formu- route. 7 Run Time Distance las, as we will see below. Running 8 A - - times are subject to change, and so Before we start writing in trip times, we take a step 9 B 8 1.4 it is simpler to enter them in general backwards--to the answer! One of the key tenets of 10 C 14 2.9 format. scheduling is to know the answer before you jump into 11 D 11 2.2 12 Total 33 6.5 the detail. In this case, looking at a few simple calcula- 13 tions (as we did above), we can see how everything will 14 pan out before we write any schedules. 15 Westbound 16 Run Time Distance 17 D - The key to this is the development of a schedule pat- 18 C 11 2.2 tern. This concept can be applied to the simplest sched- 19 B 14 2.9 ules as effectively as it can be applied to a -route 20 A 8 1.4 interline with complex branching patterns. 21 Total 33 6.5 22 The schedule pattern in effect summarizes the sched- 23 24 Garage Deadheads ule, for all or part of a day. In this case, since the running 25 Run Time Distance time and headway is constant, the schedule pattern will 26 To "A" 10 3.5 summarize operation for the entire day. 27 To "D" 20 6.8 28 29 Headway Options 30 0:06 31 0:10 32 0:12 33 0:15 34 0:20 35 0:30 36 1:00 3-9

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Chapter 3. Schedule Building Level . Building a Simple Schedule First, we enter a time for the first eastbound trip. We start with : and our schedule pattern The factor 0.00069444 Tip sheet looks like this: converts a regularly formatted number to minutes in the A B C D E F G H I J K L M time format. This factor is equiva- 1 Example Headway Sheet #1 2 ROUTE 97 Broad Street lent to 1/24/60. An alternate entry is 3 DAY Weekday TIME (x,y,z), where x is hours, y is 4 Eastbound Westbound minutes, and z is seconds. Using 5 Block # Pull Out A B C D D C B A Next Trip this, the equation in the second row 6 under B would be "=C7 + TIME (0, 7 6:00 6:33 Q12,0)." The arrival time at Point D, the end of the route, is a simple formula that takes the depart time terminal cell and adds the running time (also defined in the spreadsheet). The formula can be entered in One end point of a route where trips one of two ways: =C +( . *Q ) or =C +time( ,Q , ). usually begin and end. We already have half the schedule pattern complete and are well on the way to creating our schedule. Next we look at the return trip. It needs to depart no earlier than : (based on the minimum -minute layover). We are now faced with making a decision as to where to apply our minutes of layover time. We can apply it evenly-- minutes at each end--or we can provide different layover times at each end. In real-world operations, there are concerns with laying over for too long at some locations, which would help make our decision. On some systems, it is standard practice to give no layover at the outer terminal and allow the buses to take their time at the downtown or transit center point on the route. Others without an off-street transit center downtown may give minimal layover downtown and allocate most of its layover time at the outer terminal. In this case, we will apply minutes to each end of the route. That will give us leaving times from "D" at : and : past the hour. Having made that decision we update our schedule pattern to look like this: A B C D E F G H I J K L M 1 Example Headway Sheet #1 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 6 7 6:00 6:33 6:45 7:18 7:30 3-10

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Level . Building a Simple Schedule Chapter 3. Schedule Building Guess what? The schedule is now effectively built! First we need to check a couple of things: . How many buses? If our bus arrives back at "A" at : , and there are departures at : and : , its next possible trip would be the : trip. Is that correct according to our plan? Yes--it produces a -minute layover at each end. So how many buses do we need? This becomes a simple calculation of dividing the cycle time (inclusive of scheduled layover) by the headway. In this case, minutes (i.e., : minus : ) divided by the -minute headway is three--and there is our answer, three buses! . Are we happy with the times at the ends, and any key intermediate points? We now have a schedule pattern that we simply begin at the start of the day and end when we want our service to end. And we know how many buses we need. 4 Decide When to Start Service We still need to decide when the first trip should start in each direction. Our service plan says that service will operate from : AM to : PM. Does that mean that we must begin service in both directions at : AM? It may be obvious to you who are mathematically inclined at this point that we cannot have a : AM leaving time at the "D" point once we have decided to leave from "A" on the hour and the half-hour. A : AM arrival at "A" would not have another trip until : AM, which would be too late in returning to "D" to make the : next trip. We would end up with four buses instead of three on this route. So, what now? We are meeting the goals of the service plan by starting promptly at : AM eastbound. But our schedule pattern calls for the westbound trip to be either : or : past the hour. Is : early enough to meet the expected demand (or the intent of the service specifica- tion), or should we look at a first westbound trip at : , one cycle earlier? Knowing your system will help you answer that. The biggest question is whether there is gener- al demand in your community for service at : AM or earlier. A lot also depends on expected ridership from the east end of the route as compared to the west end. More people might be expected to travel westbound earlier due to work or school demands. If so, then a : AM trip should be the first from that direction. From an efficiency standpoint, it will be cheaper to start the trips going east, since the garage is closer to that end of the line, but that is generally less important than making sure that the schedule serves the expected ridership. If this were a fixed 3-11

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Chapter 3. Schedule Building Level . Building a Simple Schedule guideway (light rail or trolley coach) route, then it would be necessary to start out trips earlier on time than necessary in one direction to assure they are in position to start the service on time in the Defined specifically by each sys- other direction. In our case, we will make a decision based on the knowledge of our hypotheti- tem, a trip is considered on time if it cal system to have the first westbound trip leave point "D" at : AM. After adding this trip, arrives or departs from a time point your spreadsheet looks like this: within a specified range of time. A typical range is 0 to 5 minutes after A B C D E F G H I J K L M the scheduled arrival/departure 1 Example Headway Sheet #1 time. A trip that leaves a time point 2 ROUTE 97 Broad Street early is referred to as "hot" or "run- 3 DAY Weekday 4 Eastbound Westbound ning hot." 5 Block # Pull Out A B C D D C B A Next Trip 6 6:15 6:48 7:00 7 6:00 6:33 6:45 7:18 7:30 One of the beauties of spreadsheets is that if you happened to enter the : eastbound trip in Row instead of Row , you could simply insert a row to enter the westbound trip. 5 Populate the Schedule The next step is filling out the schedule. Now that we have the basic schedule pattern and have decided on the starting time in both directions, we simply repeat the schedule pattern. So east- bound trips depart "A" at : /: , and westbound trips depart "D" at : /: . This is easiest to do with a formula, in which we add thirty minutes (the headway, which is located in cell Q ) to the previous trip. Row would look like this, using the "show formula" feature: 3-12

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Level . Building a Simple Schedule Chapter 3. Schedule Building Then, after we copy the formula in row down columns C and H (corresponding to the leave times at points A and D), we have the basic schedule populated throughout the day: A B C D E F G H I J K L M N 1 Example Headway Sheet #1 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 6:48 7:00 7 6:00 6:33 6:45 7:18 7:30 8 6:30 7:15 8:00 9 7:00 7:45 8:30 10 7:30 8:15 9:00 11 8:00 8:45 9:30 12 8:30 9:15 10:00 13 9:00 9:45 10:30 14 9:30 10:15 11:00 15 10:00 10:45 11:30 16 10:30 11:15 12:00 17 11:00 11:45 12:30 18 11:30 12:15 13:00 19 12:00 12:45 13:30 20 12:30 13:15 14:00 21 13:00 13:45 14:30 22 13:30 14:15 15:00 23 14:00 14:45 15:30 24 14:30 15:15 16:00 25 15:00 15:45 16:30 26 15:30 16:15 17:00 27 16:00 16:45 17:30 28 16:30 17:15 18:00 29 17:00 17:45 18:30 30 17:30 18:15 19:00 31 18:00 18:45 32 18:30 19:15 33 19:00 3-13

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Chapter 3. Schedule Building Level . Building a Simple Schedule 6 Fill in Intermediate Times Now we can start writing trips. Using a spreadsheet this is a very simple process. Just create a depart time, and then use formulas (adding the appropriate running time minutes to the previ- ous cell). Remember that we have entered running times between time points in cells P :Q . Cells Q through Q contain eastbound running times, while cells Q through Q contain westbound running times. Using the "show formula" feature of Excel, we enter the following formulas in Row (eastbound) and Row (westbound). For space purposes, eastbound and westbound are shown separately. In the westbound example, formulas in Row have been copied to Row . The formula converts a regularly formatted number to minutes in the time format, as presented earlier. Eastbound A B C D 0.25 =C7+(0.00069444*$Q$9) =D7+(0.00069444*$Q$10) =E7+(0.00069444*$Q$11) Westbound D C B A 0.260416666666667 =H6+(0.00069444*$Q$18) =I6+(0.00069444*$Q$19) =J6+(0.00069444*$Q$20) =H6+$Q$35 =H7+(0.00069444*$Q$18) =I7+(0.00069444*$Q$19) =J7+(0.00069444*$Q$20) 3-14

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Level . Building a Simple Schedule Chapter 3. Schedule Building Formulas can also be used to add trips down the page, but it is easier to copy row (cells D : K ) down the page. In fact the whole schedule can be written with just two actual values--the first trip in each direction. The rest will flow as formulas. This allows ready manipulation of the trips and schedule, which is a key ally in a scheduler's arsenal. Using the eastbound direction as an example, the spreadsheet will look like this in "show formula" mode: 3-15

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Chapter 3. Schedule Building Level . Building a Simple Schedule This example shows the values of the filled-in spreadsheet: A B C D E F G H I J K 1 Example Headway Sheet #1 2 ROUTE 97 Broad Street 3 DAY Weekday 4 Eastbound Westbound 5 Block # Pull Out 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 Since we have said the schedule operates until : PM, we will take the literal view that this means we provide a last trip at or near that time. That provides a : PM ( : ) final trip east- bound and either a : or : trip westbound. We choose arbitrarily to offer a : trip. We can partially justify it by being closer to the garage when the trip is over. 3-16

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Level . Building a Simple Schedule Chapter 3. Schedule Building With the advent of computerized scheduling, use of the -hour clock, or military time, has become more common and is used in all our examples. Refer to the picture at right if you are not familiar with the -hour clock. Our Simple Schedule in a Computerized Scheduling Package Even if you have access to a computerized scheduling system, it is still important to go through this process. The scheduling system will certainly automate some of the things we've discussed--building multiple trips, calculating mileage and hours, and even potentially linking the trips. However, and we cannot stress this enough, the system will only produce quality outputs (i.e., schedules, blocks and runs) if the inputs have been prop- erly developed. "Garbage in, garbage out" is the simplest way to put it. So while it is true that you do not need to build an entire schedule from the start in Excel, it is still important to understand the elements of the scheduling process. Once you have defined the route, time points, running times, and distances in your system, trips are easy to create and manipulate. But what time should the trips start? How will the system link? How many buses will we need? These questions need to be asked and answered before any basic schedule is cre- ated. We recommend that you build the schedule pattern just as if you were developing the schedule without a computerized scheduling system (i.e., in a spreadsheet). Just as this process allowed us to create a schedule that would link effectively in the spreadsheet, so too will it allow us to create a schedule that links effectively in your computerized scheduling system. Even sophis- ticated scheduling packages usually cannot resolve badly written schedules. For example, if we decided to schedule trips depart from "A" at : and : , and from "D" at : and : , such a schedule pattern would result in an additional vehicle whether or not a scheduling package is used. The automated scheduler does offer some inherent capabilities to view obvious issues and work interactively with the schedules. At this point you can begin blocking. As mentioned before we started, we already "know the answer" to how many buses are required before we even do any blocking. We have in fact de- fined the schedule to ensure our answer. The next chapter discusses blocking in greater detail. 3-17

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Chapter 3. Schedule Building Level . Building a Simple Schedule LEVEL End of Basic Schedule Building. 1 The Intermediate Section of Schedule Building continues on the next page. To jump to Schedule Blocking, go to page - . 3-18