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34 of number of failures and total restoration time are provided n = Number of service periods. in Table 8, which represents a more comprehensive level of ASM = Service mode availability. reporting for this measure. The minimum data to be reported AF = Fleet availability. for this measure would be as found on Form B in Exhibit A. ASPD = Station platform door availability. 5.3.3Airport APM Performance Measure #1: Service Mode Availability Service Availability (Tier C Approach) AMOT = Actual mode operating time. The total time, in seconds, that the system was operating in the scheduled 5.3.3.1Definition operating mode, calculated by subtracting mode down- Service Availability (Tier C Approach) is the percentage of time from scheduled mode operating time (SMOT MD). time service has been available on the airport APM system, as SMOT = Scheduled mode operating time. The total time, defined herein. This availability measure, as compared to the in seconds, that the system was scheduled to provide service Tier A and Tier B availability measures, is the most compre- in the specific operating mode. hensive among the three tiers, and also the most complex. It MD = Mode downtime. The total time, in seconds, of all generally captures all events that an airport APM user could mode downtime events. perceive as a loss of availability. Mode downtime event is any of the following: Because service mode availability, fleet availability, and When any in-service train has an unscheduled stoppage station platform door availability are key components of the during the time when the system is scheduled to provide Service Availability (Tier C Approach) measure, they have been service. For unscheduled stoppages not occurring in included in this section. Service mode availability is the fraction conjunction with a station dwell, the downtime begins of the entire time the service mode has been available on the when the train reaches zero speed and ends when the system, as defined herein. Fleet availability is the fraction of train restarts (in automatic or via manual operation). For the entire time the fleet has been available in the system, as unscheduled stoppages occurring in conjunction with defined herein. And station platform door availability is the a station dwell, the downtime begins at the end of the fraction of the entire time the station platform doors have scheduled dwell time and ends when the train departs the been available in the system, as defined herein. station. Where the unscheduled stoppage occurs during Service Availability (Tier C Approach), service mode a dwell at a terminal station, and the train is taken out of availability, fleet availability, and station platform door service at the terminal station, the downtime ends when availability are defined as: all doors of the train are closed and locked at the comple- tion of the dwell. n SA TF When any in-service train has an incomplete trip on a p=1 SA C = 100 p=1 ST n scheduled route during the time when the system is scheduled to provide service. For incomplete trips where SA TF = ST A SM A F A SPD a train fails to make a station stop on its route before arriving at its destination terminal, the downtime begins AMOT at the moment the train bypasses a station and ends at A SM = SMOT the start of the next station dwell for the same train. For incomplete trips where a train fails to finish a trip on the ACOT scheduled route, the downtime begins at the moment the AF = SCOT train ceases its trip on the route and ends at the scheduled arrival time of the trip for the scheduled destination APDOT terminal on the route. A SPD = SPDOT If any of these downtime events occur at the same time or overlap one another, the earliest start time and the latest Where: end time of the events, as defined by the rules herein, are to be used in determining downtime. Service Availability (Tier C Approach) In-service train is a train located in the passenger-carrying SAC = Service Availability (Tier C Approach). portion of the system that passengers are able to use for SATF = Time-factored service availability value for each transport. period. Incomplete trip is the trip of an in-service train that fails to ST = Service time of each service period, in hours. make a station stop on the scheduled route or that fails to p = Service period. finish the trip on the scheduled route.

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35 Unscheduled stoppage is the unscheduled stopping of If any of these downtime events occur at the same time any in-service train that is not dwelling in station or the or overlap one another, the earliest start time and the latest unscheduled stopping of any in-service train that remains end time of the events, as defined by the rules herein, are in station longer than the scheduled dwell time. to be used in determining downtime. Fully functional car. An in-service car without any anomaly Fleet Availability that could be noticed by a passenger. For example, the failure of an HVAC unit on a hot day, restricted speed of a train due ACOT = Actual car operating time. The total cumulative to low tire pressure, spilled coffee on the car floor, or graffiti time, in seconds, of cars that operated within in-service etched into a window would all prevent a car from being trains. ACOT is calculated by subtracting car downtime fully functional. A car with an out-of-service coupler on from scheduled car operating time (SCOT CD). The actual the end of the train, a failed smoke detector, and a failed number of cars is not to exceed the scheduled number of hub-o-meter are examples of anomalies that may likely go cars for the time operated, either in the aggregate or in any unnoticed by passengers and therefore not prevent a car vehicle/train. from being fully functional. SCOT = Scheduled car operating time. The total cumulative In-service car is a car located in the passenger-carrying time, in seconds, of all cars scheduled to operate within portion of the system that passengers are able to use for in-service trains. SCOT is calculated by multiplying the total transport. number of cars scheduled to operate in the specific operating Where individual cars are not provided, the language mode by the time, in seconds, scheduled for that mode. in this section is to apply to vehicles. See Section 5.1.6 for CD = Car downtime. The total time, in seconds, of all car definitions and discussion of car, vehicle, and train. downtime events. Car downtime event is any of the following: Station Platform Door Availability When the car of any in-service train is not fully functional during the time when the system is scheduled to provide APDOT = Actual station platform door operating time. service. This car downtime event begins upon discovery The total time, in seconds, that station platform doors of the event or anomaly causing a car to not be fully were in service, calculated by subtracting door downtime functional and ends when the anomaly is corrected or from scheduled station platform door operating time the train is removed from service. (SPDOT DD). When the car of any in-service train is not in service SPDOT = Scheduled station platform door operating time. during the time when the system is scheduled to provide The total time, in seconds, that the station platform doors service. This car downtime event begins when the car were scheduled to be in service, calculated by multiplying is not able to be used for passenger transport and ends the scheduled number of platform doors to be in service when the car is able to be used for passenger transport by the time, in seconds. or when the train is removed from service. DD = Door downtime. The total time, in seconds, of all When an in-service train operates with fewer than the door downtime events. scheduled number of cars during the time when the Door downtime event is when any station platform door system is scheduled to provide service. This car down does not fully open upon the arrival of an in-service train. time event begins at the time when a train with a deficient This event begins when any station platform door does not number of cars is placed in service against a schedule fully open upon the arrival of an in-service train and ends that requires more cars per train; it ends when either when the in-service train departs. For door downtime events the train is removed from service or when the schedule occurring at the same or separate platforms at the same is automatically reduced due to an operating period time, the earliest start time and the latest end time of the transition, allowing the previously deficient number of events, as defined by the rules herein, are to be used in cars in the train to be sufficient. determining downtime. When the system operates with fewer in-service trains In-service train is a train located in the passenger-carrying than required by the schedule during the time when the portion of the system that passengers are able to use for system is scheduled to provide service. This car down- transport. time event begins at the time the system is operated with fewer trains than required by the schedule; it ends either Deliberately employing operating strategies to eliminate or when the scheduled number of trains are placed into stop the accumulation of downtime by exploiting the intent service or when the schedule is automatically reduced of the rules herein, especially when those strategies do not due to an operating period transition, allowing the pre- benefit the APM user, is not permitted in the context of this viously deficient number of trains to be sufficient. system of evaluation.

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36 All downtimes are to be quantified and assigned to one of the CCCS, most of what is needed thereafter are the incidental the following predefined causal categories: updates of the causes of particular events, and perhaps not much more, depending on the sophistication of the CCCS and Weather-induced. Failures caused by the weather, such as output data generated by the airport APM system. Control lightning striking the guideway, or a snow or ice storm. center personnel usually perform these updates after each Passenger-induced. Failures caused by a passenger, such as a down time event or before their shifts are complete. In many passenger holding the vehicle doors open or a passenger pull- cases, this allows reports to be automatically generated ing an emergency evacuation handle on an in-service train. (usually daily, monthly, and/or yearly) directly by the CCCS. If System equipment-induced. Failures caused by system this functionality exists within the CCCS, it is recommended equipment, such as a broken axle on an in-service train or that it be used since it could save time and effort. train control system equipment that fails while in service. Some CCCSs do not have the capability described previously Facilities-induced. Failures caused by the facilities, such but instead can dump the raw output data acquired from the as a station roof leaking water onto the floor immediately airport APM system automatically to a batch file or to some in front of one side of the station sliding platform doors, other network location connected to the CCCS. This is typically requiring a bypass of that side of the station, or a crack in done at the end of the operating day or shortly thereafter. In a guideway pier that limits the number of trains in an area. this case it may be easiest to import the data into a spreadsheet Utility-induced. Failures caused by a utility service provider, application having a file specifically developed to calculate such as the loss of an incoming electrical feed to the APM and track this performance measure. The application and system. file could be installed on a personal computer in the control O&M-induced. Failures caused by personnel affiliated with center so that staff there would have the same ability to keep the O&M organization, such as the mis-operation of the sys- the data current on each shift. It is assumed for the purpose of tem from the control center or the failure of a maintenance this guidebook and this performance measure that airport APM technician to properly isolate a piece of equipment from the systems at least have the capability to retrieve departure times active system operation on which he or she is working. (with train numbers), scheduled opening and closing times, Other. Failures caused by other issues, such as a terrorist and incomplete trip information in an electronic file format threat or delay due to the transport of a VIP. from the CCCS. Regardless of how the data are collected, some manual There are no provisions for partial service credit in this updates will need to be undertaken in the application for each measure, no allowances for grace periods, and no exclusions downtime event to ensure that the measures are recorded and for failures. This provides a measure most reflective of the reported accurately. Specifically, a cause for each downtime perspective of the airport APM user. event will need to be assigned. These causes are defined and discussed in Section 5.3.3.1. There can be one or more causes assigned to a single downtime event. For example, there may 5.3.3.2 Data Requirements and Sources be one downtime event for the day, which was initially caused The data and sources required to calculate Service Avail- by weather, but the recovery of the system was delayed further ability (Tier C Approach) are provided in Table 9. by a technician who forgot to remove his or her red tags and locks from the breakers that allow the system to be energized and restored. This oversight extended the delay by 1 hour. If 5.3.3.3Data Collection Techniques and Calculating the total downtime for the event was 2 hours, then half of the and Recording the Measure downtime (3,600 sec) would be assigned to "weather" and the It is recommended that the collection of data for the Service other half (3,600 sec) to "O&M." Availability (Tier C Approach) performance measure be To track performance over time, it is recommended that accomplished daily, since the measure will serve a useful pur- Service Availability (Tier C Approach) be calculated for the pose in describing performance when reported daily within day, month, and year, with all of those measures reported an organization. daily to the hundredth of a percent. The measures reported For this measure, most of the data will typically be collected for the month and the year are always cumulative-to-date, from records and systems in the control center. In some cases, and they reset upon the start of the new month or new year. the CCCS that is part of the ATS subsystem will have the func- For example, if the daily report is being issued for the 10th of tionality to allow user-defined reports and/or performance February for a particular year, the reported daily measure would measures to be generated based on custom rules set by the user, be for the 10th of February, the reported monthly measure and output data can be generated by the airport APM system would be the cumulative availability of days one through 10 itself. After the one-time setup of the performance measure in of February, and the reported yearly measure would be the

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37 Table 9. Data requirements and sources, Airport APM Performance Measure #1: Service Availability (Tier C Approach). Data Requirement Source Scheduled arrival and departure times, by car, vehicle, and train ATS subsystem of the ATC system; 1 number, of in-service trains at the typically recorded by the CCCS terminal stations of each route in the system Actual arrival and departure times, by car, vehicle, and train number, of ATS, CCCS 2 in-service trains at every station stop in the system System schedule, including scheduled opening and closing times of the system, scheduled start/end times of service periods, scheduled ATS, CCCS 3 number of trains and cars or vehicles per train to be in service, and scheduled headway or departure times Actual dwell start and end times, by car, vehicle, and train number, of all ATS, CCCS 4 in-service trains at every station stop in the system Location, time, and car, vehicle, and Control center logbooks 5 train number of trips not finished on Incident reports a scheduled route ATS, CCCS Times of all zero-speed and non- zero-speed indications for all in- ATS, CCCS 6 service trains, by car, vehicle, and train number and location Times and locations of in-service Control center logbooks trains placed into and taken out of 7 Incident reports service, by car, vehicle, and train ATS, CCCS number Number of automatic station System description manual 8 platform doors in the system Schedule Times of all train and station platform doors' closed and locked 9 status in the system, by car, vehicle, ATS, CCCS and train number, and terminal station location Times of train and station platform Control center logbooks door opening faults, by car, vehicle, 10 Incident reports and train number, and station ATS, CCCS location Control center logbooks 11 Cause of failures Incident reports Work orders ATS, CCCS cumulative availability of the days from January 1st through Third, the time-factored service availability values (SATF) February 10th. Downtime event causes could be reported for all service periods to be reported upon are summed. similarly. Fourth, the service times (STs) of all service periods are Service Availability (Tier C Approach) is calculated as summed. follows: Fifth, Service Availability (Tier C Approach) is calculated by dividing the sum of time-factored service availability First, service mode availability (ASM), fleet availability (AF), values for all service periods by the sum of service times and station platform door availability (ASPD) are calculated for all service periods. for each service period (i). Second, the time-factored service availability values (SATF) An example of how Service Availability (Tier C Approach) are calculated for each service period. performance measures could be reported for the day of