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Suggested Citation:"Appendix B - Airport Survey Summary." National Academies of Sciences, Engineering, and Medicine. 2019. Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems for Airports. Washington, DC: The National Academies Press. doi: 10.17226/25623.
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Suggested Citation:"Appendix B - Airport Survey Summary." National Academies of Sciences, Engineering, and Medicine. 2019. Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems for Airports. Washington, DC: The National Academies Press. doi: 10.17226/25623.
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Suggested Citation:"Appendix B - Airport Survey Summary." National Academies of Sciences, Engineering, and Medicine. 2019. Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems for Airports. Washington, DC: The National Academies Press. doi: 10.17226/25623.
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Suggested Citation:"Appendix B - Airport Survey Summary." National Academies of Sciences, Engineering, and Medicine. 2019. Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems for Airports. Washington, DC: The National Academies Press. doi: 10.17226/25623.
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Suggested Citation:"Appendix B - Airport Survey Summary." National Academies of Sciences, Engineering, and Medicine. 2019. Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems for Airports. Washington, DC: The National Academies Press. doi: 10.17226/25623.
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Suggested Citation:"Appendix B - Airport Survey Summary." National Academies of Sciences, Engineering, and Medicine. 2019. Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems for Airports. Washington, DC: The National Academies Press. doi: 10.17226/25623.
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Suggested Citation:"Appendix B - Airport Survey Summary." National Academies of Sciences, Engineering, and Medicine. 2019. Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems for Airports. Washington, DC: The National Academies Press. doi: 10.17226/25623.
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Suggested Citation:"Appendix B - Airport Survey Summary." National Academies of Sciences, Engineering, and Medicine. 2019. Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems for Airports. Washington, DC: The National Academies Press. doi: 10.17226/25623.
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Suggested Citation:"Appendix B - Airport Survey Summary." National Academies of Sciences, Engineering, and Medicine. 2019. Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems for Airports. Washington, DC: The National Academies Press. doi: 10.17226/25623.
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Suggested Citation:"Appendix B - Airport Survey Summary." National Academies of Sciences, Engineering, and Medicine. 2019. Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems for Airports. Washington, DC: The National Academies Press. doi: 10.17226/25623.
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Suggested Citation:"Appendix B - Airport Survey Summary." National Academies of Sciences, Engineering, and Medicine. 2019. Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems for Airports. Washington, DC: The National Academies Press. doi: 10.17226/25623.
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Page 126
Suggested Citation:"Appendix B - Airport Survey Summary." National Academies of Sciences, Engineering, and Medicine. 2019. Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems for Airports. Washington, DC: The National Academies Press. doi: 10.17226/25623.
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Page 127
Suggested Citation:"Appendix B - Airport Survey Summary." National Academies of Sciences, Engineering, and Medicine. 2019. Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems for Airports. Washington, DC: The National Academies Press. doi: 10.17226/25623.
×
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Page 128
Suggested Citation:"Appendix B - Airport Survey Summary." National Academies of Sciences, Engineering, and Medicine. 2019. Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems for Airports. Washington, DC: The National Academies Press. doi: 10.17226/25623.
×
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Suggested Citation:"Appendix B - Airport Survey Summary." National Academies of Sciences, Engineering, and Medicine. 2019. Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems for Airports. Washington, DC: The National Academies Press. doi: 10.17226/25623.
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115 A P P E N D I X B Airport Survey Summary The research team administered an electronic survey via Survey Monkey (online survey software) to solicit information from a broad range of airports regarding the challenges to optimal utilization of gate electrification systems. The airport survey was undertaken to supplement the findings from the in- person focus group meetings and the web-enabled case study interviews. The survey was distributed to airports via airport trade associations (ACI-NA and AAAE) as well as distributed directly to airports by members of the research team. A total of 34 airports responded to the survey, six of which also participated as either a focus group or case study airport; therefore, the survey was successful in obtaining information from an additional 28 airports not already covered by the focus groups and case studies. Some of the airports skipped certain questions; therefore, the summary data below for certain questions contain results with fewer than 34 responses. The survey questions were developed based on initial focus group and case study stakeholder input. The survey was also reviewed and approved by the project panel. It included questions covering electric preconditioned air (PCA) units and electric ground power systems (collectively referred to as gate electrification systems), utilization tracking practices, maintenance of systems, equipment procurement, regulatory requirements, and stakeholder policies. This appendix provides a description of the methodology and assumptions and the summary of the responses received. 1. Survey Respondents Summary Data This section covers aggregated demographic characteristics of the respondent airports, including airport hub sizes, climatic zones, National Ambient Air Quality Standards (NAAQS) attainment status, and VALE eligibility (U.S. airports only). Respondent Hub Sizes Survey respondents represent a variety of hub sizes. As presented in Figure 42, 23 percent are large hub, 24 percent are medium hub, 29 percent are small hub, 15 percent are non-hub, and 9 percent are Canadian.

116 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports Respondent Climatic Zones Respondent airports are located across the U.S. and Canada and cover 7 ASHRAE climatic zones. ASHRAE standards are intended to provide climatic data for use in building design and equipment standards. Figure 43 presents the percentage of respondents that fall into each thermal climate zone represented, Zones 1-7. ASHRAE zones are denoted by a number (based on heating and cooling degree days) and a letter, which represents the subtype: Humid (A), Dry (B) or Marine (C) (Subtype is determined based on annual mean temperature and precipitation data). Figure 44 shows the distribution of airports across the climate zones and subtype. Figure 43. Percentage of respondents representing ASHRAE Thermal Zones 1-7. 3% 15% 23% 18% 20% 15% 6% Zone 1 Zone 2 Zone 3 Zone 4 Zone 5 Zone 6 Zone 7 Figure 42. Percentage of respondents representing each hub size. Large Medium Small Non-hub Canadian 23% 24%29% 15% 9%

Airport Survey Summary 117 NAAQS Status of Respondents The survey included a question on the NAAQS status to determine which airports are in nonattainment or maintenance zones for the six criteria pollutants (ground level ozone, carbon monoxide, particulate matter, nitrogen dioxide, sulfur dioxide, and lead) regulated under the Clean Air Act by the U.S. EPA (and thus eligible to receive VALE grants). As shown in Figure 45, 35 percent of airport respondents are in attainment under the NAAQS, 18 percent are in maintenance zones, and 38 percent are in nonattainment zones (the remainder are Canadian airports, and the NAAQS do not apply). 35% 18% 38% 9% Attainment Maintenance Nonattainment Canadian Figure 45. NAAQS status of respondents. VALE Eligibility Fifty-six percent of respondent airports are eligible for VALE funding, while 44 percent are not eligible. In order for airports to be eligible for VALE funding, they must be located in nonattainment or maintenance areas for one or more of the six criteria pollutants. 2. Airport Gate Electrification Equipment The survey contained a number of questions regarding airports’ gate electrification equipment, including the number of gates, the number of remote hardstands, the number of gates with electric preconditioned air (PCA) and ground power, mobile units in use, etc. Figure 44. Number of respondents in each ASHRAE moisture zone (A= Humid, B=Dry, C= Marine). 0 1 2 3 4 5 6 0 1A 1B 2A 2B 3A 3B 3C 4A 4B 4C 5A 5B 5C 6A 6B 7 8 RE SP O N DE N T CO U N T CLIMATIC ZONE

118 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports Gate ownership In terms of gate ownership, 85 percent of respondents reported that all gates are airport-owned. The remaining 15 percent reported a combination of both airport and airline-owned gates (see Figure 46). Figure 47. PCA system types as reported by respondents. Figure 46. Gate ownership as reported by respondents. PCA system type As shown in Figure 47, most respondents have point-of-use PCA systems (24 respondents). Five of the respondent airports have both a central PCA system and point-of-use systems. One airport reported having a central PCA system and no point-of-use PCA equipment. Gate equipage A majority of respondents, 68 percent, reported that at least 95 percent of gates at their airport are equipped with both electric PCA and ground power. The remaining 32 percent of the respondents reported varying levels of equipage. For example, a few airports reported that all gates are equipped with electric ground power but none with PCA. Other respondents reported having a mix of equipage at gates, some with both PCA and ground power, and some with just ground power. One airport reported no gate electrification equipment in place at all.

Airport Survey Summary 119 Figure 48. Diesel- or propane-powered mobile PCA or GPU. Remote hardstand positions at the airport A majority of respondents (88 percent) have remote “hardstand” positions at the airport. Use of hardstands The uses of hardstands vary by respondent, but the majority of respondents do not use hardstands for regular passenger loading and unloading operations. The most common use identified was overnight parking only (45 percent of respondents), shown in Figure 49. 0 0 0 0 0 1 1 2 2 2 3 3 3 4 4 4 4 5 5 6 10 10 20 56 142 0 20 40 60 80 100 120 140 160 Y X W V U T S R Q P O N M L K J I H G F E D C B A Number of diesel or propane powered mobile PCA or ground power units in use at the airport Ai rp or t R es po nd en t Mobile diesel- or propane-powered PCA or GPUs As shown in Figure 48, of the 25 airports that had data to report on diesel- or propane-powered mobile PCA and GPUs in service at the airport, most had fewer than 10 mobile units, while one airport reported 142 mobile PCA and GPUs.

120 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports Figure 49. Use of remote hardstand positions as reported by respondents. 3. Utilization Tracking The survey sought to capture data related to airports’ practices and methodology for tracking PCA and ground power system utilization. Utilization tracking practices A majority of airport respondents report that they do not track PCA and ground power utilization (68 percent). Close to 18 percent report that they do track utilization and the remainder were not sure (see Figure 50). Of the 6 airports that reported tracking PCA and /or ground power system utilization, all have used VALE grants and are, therefore, required to track hours of use for emissions savings calculations. Of airports that are either ineligible for VALE or are eligible but have not used a VALE grant, none reported tracking utilization. Figure 50. Airports that reported tracking PCA and/or ground power utilization.

Airport Survey Summary 121 Tracking methods The survey sought to collect information regarding how utilization is tracked. The following responses were received: • Informal Excel spreadsheet; • PCA run time hours are tracked quarterly with equipment meters and catalogued in annual reports; • Periodic readings from equipment meters are taken when needed; • Hour meters are on the equipment, and the airport has started manually entering the data into their computerized maintenance monitoring system. Hours of use are tracked for equipment acquired with the VALE grant and reported to FAA; and • Equipment use is monitored with meters (for time in use). The survey asked airports for the approximate utilization rate of their electric PCA and ground power equipment, and only a few estimates were provided, including: • 90 percent • 100 percent • “Medium to high” Auxiliary power unit usage While some airports track PCA and ground power utilization by hours of run time, the research team was interested in whether any airports are also tracking APU use when aircraft are parked at the gate. Only one airport reported tracking APU use by aircraft while parked at gates. When the research team discussed this practice further with the responding airport, it was clarified that the airport does not track actual APU use while aircraft are at the gate. The airport looks at the hours of PCA run time and the flight schedules to determine estimated emissions savings from use of PCA as per required by the FAA for VALE grant recipients. Metering equipment According to results summarized in Figure 51, most airport respondents do not have individual electrical meters on jet bridges (55 percent), although 39 percent of respondents report that some or all of their bridges are individually metered (while some airports jet bridges are metered, the individual PCA and ground power system components may not be).

122 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports Figure 51. Jet bridge metering. 4. Maintenance of Equipment The survey sought to collect information on maintenance of PCA systems and ground power equipment. This includes the parties responsible for maintenance, as well as communication and coordination methods between stakeholders. Maintenance of electric PCA and ground power equipment Approximately half of respondents (51 percent) reported that either airport staff or airport-provided third-party service providers maintain the electric PCA and ground power systems. Only 4 respondents reported that these systems are maintained by airline staff or airline-provided contractors (approximately 11 percent). The remaining respondents reported that a combination of these parties are responsible for maintenance as shown in Figure 52.

Airport Survey Summary 123 Figure 52. Maintenance of electric PCA and ground power equipment. 5. Communication Protocols Participants in the focus groups and case study interviews noted the importance of communication between the airport, airlines, and maintenance and ground crews regarding the availability and status of the gate electrification equipment. The survey included two questions on communication about electric PCA and ground power equipment status: 1. how airlines notify airports of damaged or inoperable equipment, and 2. how airports notify airlines when equipment has been repaired and is back in service. Both of these questions were open-ended (i.e. no pre-set answers). Notification when equipment is out of service Sixty-four percent of respondents reported that ground handlers or airline staff contact airport operations or maintenance departments directly when there is a problem with the PCA or ground power equipment. An additional 18 percent replied that airlines notify the airport via a designated telephone number or hotline, but did not specify if the number was to operations, maintenance or other airport department. The remaining 18 percent replied that the question did not apply or that they were unsure of the communication protocols. Notification when equipment is back in service Once the electric PCA and ground power equipment has been restored to service, the parties responsible for maintaining the equipment notify the airlines. A range of answers for how this communication takes place was provided, but in general, 46 percent of airports reported using email and/or phone notifications, 27 percent reported some sort of direct verbal communication with airline staff, and 15 percent reported using some form of automatic notification. The remaining responses varied, including equipment status indicated on each gate, or the question was not applicable (i.e., if the airport does not maintain the equipment). 32% 11% 8%11% 38% airport staff only airport staff and airport provided contractors airport provided contractors only airline staff or airline provided contractors combination

124 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports General communication protocols The survey included an open-ended question about communication practices between the airport and airlines (not limited to the status of PCA and ground power equipment). Some airports provided multiple methods of communication. Aggregated method types are included in Figure 53. Based on responses, the most common forms of communication are in-person, phone, and email. Figure 53. Communication methods utilized for airport and airline coordination. 6. System procurement and policy The survey collected information concerning procurement of PCA and ground power systems, as well as policies in place to govern their use. Primary drivers for equipment acquisition Airport respondents were given a range of possible motivating factors for acquiring and installing gate electrification equipment (and were able to select multiple responses). The two most common primary drivers that airports reported affecting their decision to acquire and install this equipment are: 1. provide the service to airlines, and 2. airport leadership commitment. Results are depicted in Figure 54. 0 5 10 15 20 25 In-person Phone Email Control center PASSUR system Reports N um be r o f a irp or t re sp on de nt s

Airport Survey Summary 125 Figure 54. Primary drivers for PCA/ ground power installation. Financing the acquisition, maintenance, and operation of equipment Several mechanisms are employed by airports to finance the installation, operation, and maintenance of their electric PCA and ground power systems. Respondents were able to check all that applied to their airport. Based on responses, the most common funding comes from capital improvement programs, operating budgets, and VALE grants. Some examples of “other” items listed by airport respondents include Passenger Facility Charge (PFC) funds, Airport Improvement Program (AIP) funds, and terminal construction/ re-construction projects (see Figure 55). Figure 55. Mechanisms used to finance PCA/ ground power systems.

126 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports Electricity costs Airports were asked how they charge airlines for the electricity costs associated with electric PCA and ground power utilization. According to survey results, a majority of airport respondents charge airlines for electricity use through incorporation in lease rates and charges, as opposed to charging airlines for actual electricity use (which would require individual electrical meters on gates and equipment, and mechanisms for tracking use on shared gates). This was an open-ended question, and responses were categorized into the general categories listed in Figure 56. The intent of the research team in including this question on the survey was to determine if there is a link between how airlines are charged for electricity and utilization tracking practices and utilization rates. The lack of electrical meters on equipment at most airports results in those airports being unable to determine PCA and ground power use by electricity consumption. In addition, the general lack of utilization tracking prevents the establishment of a relationship between how airlines are charged for electricity and utilization rates. Cost–benefit analysis for gate electrification systems The survey asked respondents if they conducted a cost–benefit analysis (CBA) for the acquisition and installation of electric PCA and ground power. About half of respondent airports (51 percent) reported that they did not conduct a CBA, 18 percent did perform some sort of CBA, and the remainder did not know whether a CBA had been performed. Although the application process for FAA VALE grants requires the airport applicant to estimate the cost per ton of pollutant reduced through the project, a number of airports that received VALE grants for PCA/ground power equipment reported that they did not conduct a CBA or did not know if a CBA have been conducted. This inconsistency may be attributed to unclear wording on the survey instrument (i.e., airports were not specifically instructed that estimates prepared for VALE applications could be considered a CBA). Further, VALE grant applications do not consider GHGs as part of the emission reductions estimates. 0 5 10 15 20 25 N um be r o f a irp or t r es po nd en ts Figure 56. Methods for charging airlines for electricity. Le ase Ra te Me ter ed N/ A Fix ed fe e p er co nn ec tio n By sq ua re- foo tag e La nd ing fe es

Airport Survey Summary 127 Policies regarding PCA and ground power use Airport respondents were asked if they have any policies, incentives or regulations to encourage airline use of electric PCA and ground power equipment (Figure 57). The majority of respondents (64 percent) do not have any policies or incentives in place regarding the use of electric PCA and ground power by aircraft. There were 6 airports (18 percent) that reported some type of policy or incentive in place, and 6 airports that reported they were unsure if the airport had a policy in place. Of the 6 airports with policies encouraging the use of electric PCA and ground power, 4 have used VALE grants to acquire at least some of their PCA and ground power equipment. One example of an airport policy that encourages use of PCA and ground power is from Philadelphia International Airport. Their Rules and Regulations Manual states in Section 3, Aircraft Operations, “Operators should use ground power and pre-conditioned air when available and practicable” (pages 3– 9). Another example is from San Diego County Regional Airport Authority, which has a Memorandum of Understanding with the Attorney General of California requiring San Diego International Airport to equip gates with electric PCA and ground power, and to coordinate with the airlines on the design and provision of the equipment (SDCRAA MOU, 2008). 7. Challenges and barriers to utilization The survey asked airports to identify the main challenges to utilization of electric PCA and ground power, and provided both a selection of pre-set answers and an open-ended response option. Over half of airport respondents identified ground crew equipment misuse and kinked PCA hoses as challenges or barriers to utilization. Although kinked hoses can be caused by incorrect deployment or storage of the PCA hose (which could result from incorrect equipment use), this challenge in particular was cited frequently enough by focus group and case study participants that the research team included this as a separate answer choice (see Figure 58). 18% 64% 18% yes no not sure Figure 57. Airports with policies or incentives for airline PCA and ground power use.

128 Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems at Airports Figure 58. Challenges to PCA and ground power utilization. 8. Survey conclusions While the survey results cannot be interpreted to represent all airports in the U.S., the 34 airport respondents do represent a range of airport sizes, geographic locations, climate zones, and local air quality status. The results of the survey combined with the focus group and case study interviews provided the research team with an understanding of the different types of electric PCA and ground power configurations, ownership and maintenance structures, drivers for installation, utilization tracking methodologies in place, and common challenges to electric PCA and ground power use. Some of the conclusions drawn from the survey results include: • The primary driver why airports install gate electrification equipment is to provide the service to airlines. This fact suggests airports recognize it is not cost-effective for airlines to provide gate power and conditioning through APUs and diesel power GPUs. • Airports are funding installation of this equipment with their own financial resources more often than relying on matching funds. • Airports located in non-attainment zones are using VALE funds. However, about half of respondents are in non-attainment zones, indicating that just as many airports that are not eligible for VALE are implementing gate electrification measures. These data support responses that the primary driver is not regulatory or environmental, but service to the airlines. 0 5 10 15 20 25 N um be r o f a irp or t r es po nd en ts Ground crew misuse of equipment PCA hose kinked or damaged Ground power cable damaged Equipment out of service for other reason Short turn times High ambient temperatures (PCA can't cool aircraft effectively) Other (open ended) Not all gates equipped Equipment not right-sized for aircraft Low ambient temperatures (PCA can't heat aircraft effectively) Weather hazards for ground crew Dislodged hose insulation clogs aircraft air intake

Airport Survey Summary 129 • Few airports track equipment utilization. This makes it difficult to ascertain level of equipment use and opportunities for optimization. • The cost of operations and maintenance is not tracked. Investing in tracking equipment could result in cost savings to the airport. • The primary barrier to use is non-functioning equipment, and kinked hoses have been a specific issue. • Airports and airlines have established direct lines of communication to address gate electrification equipment operational issues. Airports that have received VALE grants are required to track use of equipment purchased with the grant funds for the purposes of calculating emissions savings. However, beyond those airports tracking hours of use for VALE purposes, airports are generally not tracking utilization in any kind of formal, systematic manner. Several airports interviewed for the case studies and in this survey reported anecdotally that utilization rates are high, but there was no precision provided. The data do not support conclusions correlating individual airport characteristics and practices with specific increases or decreases in electric PCA and ground power utilization. However, the survey data do support the findings from the focus groups and case study interviews regarding the identification of common challenges, and general solutions.

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As demand for air travel grows, airport-related emissions are increasing and airports are challenged to reduce associated environmental impacts. In response, expanded regulatory programs and global climate protection initiatives are being developed that require the aviation industry—including U.S. airports—to implement new, clean technologies and to modify operational practices to reduce emissions.

One effective option for reducing the emissions associated with aircraft auxiliary power units (APUs) and diesel-powered gate equipment is to convert to electric PCA and electric ground power systems, collectively referred to as “gate electrification systems.”

The TRB Airport Cooperative Research Program's ACRP Research Report 207: Optimizing the Use of Electric Preconditioned Air (PCA) and Ground Power Systems for Airports provides guidance in identifying and understanding factors that contribute to the use or non-use of gate electrification systems (electric preconditioned air or PCA and electric ground power systems) and ways that airports and airlines can optimize the use of the systems.

This research includes case studies at a variety of types and sizes of airports in different climates; an evaluation of how weather and climate impact utilization; the use and impact of other available ground power and PCA units; consideration of aircraft hardstand operations; and airport and airline practices for optimal equipment utilization.

The work includes additional resources: the ACRP 02-76 Ground Power and PCA Example Utilization Tracking Methodology and the Self-Assessment Checklist.

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