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30 Table 6. Example reporting of airport APM Performance Measure #1: Service Availability (Tier A Approach). February 10, 2010 Day Month-to-Date Year-to-Date Service Availability 91.67% 98.00% 98.89% (Tier A Approach) Downtime, by Category, for February 10, 2010 Day Month-to-Date Year-to-Date Weather 3,600 sec 4,320 sec 4,320 sec Passenger -- 4,320 sec 12,833 sec System equipment -- 4,320 sec 9,803 sec Facilities -- -- -- Utility -- -- -- O&M 3,600 sec 4,320 sec 4,500 sec Other -- -- 7,864 sec Total 7,200 sec 17,280 sec 39,320 sec by weather, but the recovery of the system was delayed further capture all system events that an airport APM user could per- by a technician who forgot to remove his or her red tags and ceive as a loss of availability. For example, actual line capacity locks from the breakers that allow the system to be energized as compared to the scheduled line capacity (in terms of train and restored. This oversight extended the delay by 1 hour. consist sizes) is not addressed by this measure. Another, head- If the total downtime for the event was 2 hours, then half of way performance, is not directly captured by this measure but the downtime (3,600 sec) would be assigned to "weather" and may be reflected in the Service Availability (Tier B Approach) the other half (3,600 sec) to "O&M." measure if a failure occurs. The service availability approaches To track performance over time, it is recommended that in this and subsequent sections become more comprehensive Service Availability (Tier A Approach) be calculated for the day, than the Service Availability (Tier A Approach) measure by month, and year, with all of those measures reported daily to capturing a greater share of those events, and carry with them the hundredth of a percent (See Section 4.3.1.1). The measures a greater level of sophistication as well. reported for the month and year are always cumulative-to-date, Because service reliability (MTBF) and service maintain- and they reset upon the start of the new month or new year. For ability (MTTR) are key components of the Service Availabil- example, if the daily report is being issued for the 10th of Febru- ity (Tier B Approach) measure, they have been included in ary for a particular year, the reported daily measure would be this section. Service reliability (MTBF) is the mean amount for the 10th of February, the reported monthly measure would of time that the system has operated before experiencing a be the cumulative availability of days one through 10 of Febru- failure. Service maintainability (MTTR) is the mean amount ary, and the reported yearly measure would be the cumulative of time that it has taken to restore service on the system once availability of the days from January 1st through February 10th. a failure has occurred. Downtime event causes could be reported similarly. Service Availability (Tier B Approach), service reliability An example of how Service Availability (Tier A Approach) (MTBF), and service maintainability (MTTR) are defined as: performance measures could be reported for the day of Feb- ruary 10, 2010, and the associated assignment of downtime MTBFp are provided in Table 6, which represents a more comprehen- SA B = 100 ( MTBFp + MTTR p ) sive level of reporting for this measure. The minimum data to be reported for this measure would be as found on Form B in Exhibit A. SOTp MTBF = NFp 5.3.2Airport APM Performance Measure #1: Service Availability (Tier B Approach) NFp TTR F MTTR = F=1 NFp 5.3.2.1Definition Service Availability (Tier B Approach) is the percentage of Where: time service has been available on the airport APM system, as defined herein. In an effort to limit the complexity of the SAB = Service Availability (Tier B Approach). measure and provide an alternate means of calculating ser- MTBF = Mean time between failure = service reliability. vice availability, the measure deliberately does not attempt to MTTR = Mean time to restore = service maintainability.

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31 p = The represented period of time, typically the day, month- train is taken out of service at the terminal station, the to-date, or year-to-date. total time to restore ends when all doors of the train are SOT = Scheduled operating time. The total time in seconds closed and locked at the completion of the dwell. that the system was scheduled to provide service. When multiple failures occur at the same time, during F = Failure. Failure is any of the following: the same incident, or due to the same malfunction, the When any in-service train has an unscheduled stoppage total time to restore begins at the earliest start time of the during the time when the system is scheduled to provide failures and ends at the latest end time of the failures. service. In-service train is a train located in the passenger-carrying When any in-service train has an incomplete trip on portion of the system that passengers are able to use for a scheduled route during the time when the system is transport. scheduled to provide service. Incomplete trip is the trip of an in-service train that fails to When any vehicle or station platform door blocks any make a station stop on the scheduled route or that fails to portion of the nominal doorway opening that passen- finish the trip on the scheduled route. gers use to board and alight trains dwelling in the station Unscheduled stoppage is the unscheduled stopping of any during the time when the system is scheduled to provide in-service train that is not dwelling in the station or the service. unscheduled stopping of any in-service train that remains NFp = Number of failures for the period. The total number in the station longer than the scheduled dwell time. of all failures in the period. (Multiple failures occurring at the same time, during the same incident, or due to the Deliberately employing operating strategies to eliminate or same malfunction are to be counted as one failure.) stop the accumulation of downtime by exploiting the intent TTR = Total time to restore. The total time to restore ser- of the rules herein, especially when those strategies do not benefit the APM user, is not permitted in the context of this vice after a failure, calculated as follows: system of evaluation. For unscheduled stoppages not occurring in conjunc- All failures and total restoration times are to be quanti- tion with a station dwell, the total time to restore begins fied and assigned to one of the following predefined causal when the train reaches zero speed and ends when the categories: train restarts (in automatic or via manual operation). For unscheduled stoppages occurring in conjunction Weather-induced. Failures caused by the weather, such as with a station dwell, the total time to restore begins at lightning striking the guideway, or a snow or ice storm. the end of the scheduled dwell time and ends when the Passenger-induced. Failures caused by a passenger, such as a train departs the station. Where the unscheduled stop- passenger holding the vehicle doors open or a passenger pull- page occurs during a dwell at a terminal station, and ing an emergency evacuation handle on an in-service train. the train is taken out of service at the terminal station, System equipment-induced. Failures caused by system the total time to restore ends when all doors of the train equipment, such as a broken axle on an in-service train, or are closed and locked at the completion of the dwell. train control system equipment that fails while in service. For incomplete trips where a train fails to make a sta- Facilities-induced. Failures caused by the facilities, such tion stop on its route before arriving at its destination as a station roof leaking water onto the floor immediately terminal, the total time to restore begins at the moment in front of one side of the station sliding platform doors, the train bypasses a station and ends at the start of the requiring a bypass of that side of the station, or a crack in next station dwell for the same train. a guideway pier that limits the number of trains in an area. For incomplete trips where a train fails to finish a trip Utility-induced. Failures caused by a utility service provider, on the scheduled route, the total time to restore begins such as the loss of an incoming electrical feed to the APM at the moment the train ceases its trip on the route and system. ends at the scheduled arrival time of the trip for the O&M-induced. Failures caused by personnel affiliated with scheduled destination terminal on the route. the O&M organization, such as the mis-operation of the For vehicle or station platform doors that block any system from the control center or the failure of a maintenance portion of the nominal doorway opening that passen- technician to properly isolate a piece of equipment from gers use to board and alight trains dwelling in station, the active system operation on which he or she is working. the total time to restore begins at the moment a door Other. Failures caused by other issues, such as a terrorist blocks any portion of the nominal doorway opening threat or a delay due to the transport of a VIP. during the dwell and ends when the train departs the station. Where blockage of the nominal doorway open- There are no provisions for partial service credit in this ing occurs during a dwell at a terminal station, and the measure, no penalties for line capacity reductions (i.e., shorter

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32 trains), no allowances for grace periods, and no exclusions for For these measures, most of the data will typically be col- failures. This maintains the simplicity and usability of the lected from records and systems in the control center. In some measure while providing a measure most reflective of the cases, the CCCS that is part of the ATS subsystem will have perspective of the airport APM user. the functionality to allow user-defined reports and/or perfor- mance measures to be generated based on custom rules set by the user, and output data can be generated by the airport 5.3.2.2 Data Requirements and Sources APM system itself. After the one-time setup of the performance The data and sources required to calculate Service Avail- measures in the CCCS, most of what is needed thereafter are ability (Tier B Approach), service reliability (MTBF), and the incidental updates of the causes and numbers of particular service maintainability (MTTR) are provided in Table 7. failures, and perhaps not much more, depending on the sophis- tication of the CCCS and output data generated by the airport APM system. Control center personnel usually perform these 5.3.2.3Data Collection Techniques and Calculating updates after each downtime event or before their shifts are and Recording the Measure complete. In many cases, this allows reports to be automati- It is recommended that the collection of data for the Service cally generated (usually daily, monthly, and/or yearly) directly Availability (Tier B Approach), service reliability (MTBF), by the CCCS. If this functionality exists within the CCCS, it is and service maintainability (MTTR) performance measures recommended that it be used since it could save time and effort. be accomplished daily, since the measures will serve a use- Some CCCSs do not have the capability described previ- ful purpose in describing performance when reported daily ously, but instead can dump the raw output data acquired within an organization. from the airport APM system automatically to a batch file or Table 7. Data requirements and sources, Airport APM Performance Measure #1: Service Availability (Tier B Approach). Data Requirement Source Scheduled arrival and departure ATS subsystem of the ATC system; times, by train number, of in-service 1 typically recorded by the CCCS trains at the terminal stations of each route in the system Actual arrival and departure times, ATS, CCCS 2 by train number, of in-service trains at every station stop in the system Scheduled opening and closing times ATS, CCCS 3 of the system Actual dwell start and end times, by ATS, CCCS 4 train number, of all in-service trains at every station stop in the system Location, time, and train number of Control center logbooks 5 trips not finished on a scheduled Incident reports route ATS, CCCS Times of all zero speed and non-zero ATS, CCCS 6 speed indications for all in-service trains, by train number and location Times and locations of in-service Control center logbooks 7 trains taken out of service, by train Incident reports number ATS, CCCS Times of all vehicle and station platform doors' closed and locked ATS, CCCS 8 status in the system, by train number and terminal station location Times of vehicle and station platform Control center logbooks 9 door opening faults, by train number Incident reports and station location ATS, CCCS Control center logbooks 10 Number of failures Incident reports ATS, CCCS Control center logbooks 11 Cause of failures Incident reports Work orders ATS, CCCS

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33 to some other network location connected to the CCCS, for a door opening fault at every station at which the train dwells, example. This is typically done at the end of the operating day this would need to be reflected as one failure in the applica- or shortly thereafter. In this case it may be easiest to import tion rather than as multiple failures coincident with the door the data into a spreadsheet application having a file specifi- opening faults at each of the stations. cally developed to calculate and track this performance mea- To track performance over time, it is recommended that Ser- sure. The application and file could be installed on a personal vice Availability (Tier B Approach), service reliability (MTBF), computer in the control center so that staff there would have and service maintainability (MTTR) be calculated for the day, the same ability to keep the data current on each shift. It is month, and year, with Service Availability (Tier B Approach) assumed for the purpose of this guidebook and performance reported daily to the hundredth of a percent, and service reli- measure that airport APM systems at least have the capabil- ability (MTBF) and service maintainability (MTTR) reported ity to retrieve the data described in numbers 1 through 10 daily in hours, minutes, and seconds. The measures reported of Table 7 electronically from the CCCS. If not, and if the for the month and year are always cumulative-to-date, and they control center manually logs all actions or events that occur reset upon the start of the new month or new year. For example, throughout the operating day, then whatever information if the daily report is being issued for the 10th of February cannot be obtained electronically from the CCCS will have for a particular year, the reported daily measures would be to be mined manually from the logbook and other locations for the 10th of February, the reported monthly measures as described in Table 7. would be the cumulative availability of days one through 10 Regardless of how the data are collected, some manual of February, and the reported yearly measures would be the updates will need to be undertaken in the application for each cumulative availability of the days from January 1st through failure to ensure that the measures are recorded and reported February 10th. accurately. Specifically, a cause for each failure will need to The number of failures and total time to restore could be be assigned. These causes are defined and discussed in Sec- reported similarly, by causal category. The example provided tion 5.3.2.1. There can be one or more causes assigned to a in Table 6 reflected downtime for the Service Availability single failure. For example, there may be one failure for the (Tier A Approach) performance measure being reported in day, which was initially caused by weather, but the recovery seconds. That could be replicated for the reporting of total time of the system was delayed further by a technician who forgot to restore under this Service Availability (Tier B Approach) to remove his or her red tags and locks from the breakers that performance measure, but is reported in Table 8 in hours, allow the system to be energized and restored. This oversight minutes, and seconds for the sake of comparing the two report- extended the delay by 1 hour. If the total time to restore for ing units. the event was 2 hours, then half of it (3,600 sec) would be as- An example of how the Service Availability (Tier B Ap- signed to "weather" and the other half (3,600 sec) to "O&M." proach), service reliability (MTBF), and service maintain- Similarly, the number of failures may need to be manually ability (MTTR) performance measures could be reported for updated. For example, if a train has a failed door and there is the day of February 10, 2010, and the associated assignment Table 8. Example reporting of airport APM Performance Measure #1: Service Availability (Tier B Approach). February 10, 2010 Day Month-to-Date Year-to-Date Service Availability 99.17% 99.88% 98.50% (Tier B Approach) Service reliability 10:00:00 80:00:00 06:34:00 (MTBF) Service maintainability 00:05:00 00:06:00 00:06:10 (MTTR) Failures and Total Time To Restore (TTR), by Category, for February 10, 2010 Day Month-to-Date Year-to-Date Failures TTR Failures TTR Failures TTR Weather -- -- -- -- 5 03:00:00 Passenger 1 00:06:00 10 01:26:00 75 02:45:00 System equipment 1 00:04:00 8 00:30:00 30 01:30:00 Facilities -- -- 1 00:20:00 4 00:30:00 Utility -- -- 2 00:04:00 4 04:00:00 O&M -- -- 4 00:10:00 6 00:20:00 Other -- -- -- -- 1 00:46:00 Total 2 00:10:00 25 02:30:00 125 12:51:00