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Advanced Ground Vehicle Technologies for Airside Operations (2020)

Chapter: Chapter 4 - Prioritized Airside Applications

« Previous: Chapter 3 - Applications and Lessons Learned
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Suggested Citation:"Chapter 4 - Prioritized Airside Applications." National Academies of Sciences, Engineering, and Medicine. 2020. Advanced Ground Vehicle Technologies for Airside Operations. Washington, DC: The National Academies Press. doi: 10.17226/26017.
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Suggested Citation:"Chapter 4 - Prioritized Airside Applications." National Academies of Sciences, Engineering, and Medicine. 2020. Advanced Ground Vehicle Technologies for Airside Operations. Washington, DC: The National Academies Press. doi: 10.17226/26017.
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Suggested Citation:"Chapter 4 - Prioritized Airside Applications." National Academies of Sciences, Engineering, and Medicine. 2020. Advanced Ground Vehicle Technologies for Airside Operations. Washington, DC: The National Academies Press. doi: 10.17226/26017.
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Suggested Citation:"Chapter 4 - Prioritized Airside Applications." National Academies of Sciences, Engineering, and Medicine. 2020. Advanced Ground Vehicle Technologies for Airside Operations. Washington, DC: The National Academies Press. doi: 10.17226/26017.
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Suggested Citation:"Chapter 4 - Prioritized Airside Applications." National Academies of Sciences, Engineering, and Medicine. 2020. Advanced Ground Vehicle Technologies for Airside Operations. Washington, DC: The National Academies Press. doi: 10.17226/26017.
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Suggested Citation:"Chapter 4 - Prioritized Airside Applications." National Academies of Sciences, Engineering, and Medicine. 2020. Advanced Ground Vehicle Technologies for Airside Operations. Washington, DC: The National Academies Press. doi: 10.17226/26017.
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Suggested Citation:"Chapter 4 - Prioritized Airside Applications." National Academies of Sciences, Engineering, and Medicine. 2020. Advanced Ground Vehicle Technologies for Airside Operations. Washington, DC: The National Academies Press. doi: 10.17226/26017.
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Suggested Citation:"Chapter 4 - Prioritized Airside Applications." National Academies of Sciences, Engineering, and Medicine. 2020. Advanced Ground Vehicle Technologies for Airside Operations. Washington, DC: The National Academies Press. doi: 10.17226/26017.
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Suggested Citation:"Chapter 4 - Prioritized Airside Applications." National Academies of Sciences, Engineering, and Medicine. 2020. Advanced Ground Vehicle Technologies for Airside Operations. Washington, DC: The National Academies Press. doi: 10.17226/26017.
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Suggested Citation:"Chapter 4 - Prioritized Airside Applications." National Academies of Sciences, Engineering, and Medicine. 2020. Advanced Ground Vehicle Technologies for Airside Operations. Washington, DC: The National Academies Press. doi: 10.17226/26017.
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41 This chapter presents a variety of airside AGVT applications and technologies. It describes how the candidate applications and technologies were prioritized to identify technology applications for a more detailed evaluation in Chapter 6. Candidate Applications The applications described in Chapter 3 and insight from the research team were the basis for the development of a list of candidate airside applications and a list of candidate technologies. The candidate lists were intended to catalog and conceptualize applications, and thus were not limited by current technological feasibility, which is addressed in the evaluation phase. Candidate airside applications were based into two broad categories reflecting (1) ramp and aircraft activities and (2) airport operations. Ramp and aircraft activities include bringing baggage carts to the aircraft, aircraft parking, ramp services, and aircraft tugs and towing. Ramp and aircraft activities are often the responsibility of airlines or vendors. Airport opera- tions support airport maintenance and inspection requirements and include runway inspec- tions, perimeter inspections for security, and snow removal. Airport operations are often the responsibility of airport personnel. After approval of the candidate applications and technolo- gies by the ACRP Panel, the airside applications shown in Table 5 and the candidate technologies shown in Table 6 were presented to airport stakeholders for feedback. Airport Stakeholders were also invited to identify additional applications and technologies that were not specifically identified by the research team. Ramp and Aircraft Activities Many of the ramp and aircraft activities are conducted near the terminal in the non-movement area. Often space is constrained and there are a lot of activities underway simultaneously, which may present special considerations in terms of obstacle avoidance and coordination, but may also present opportunities for operational improvements through AGVT. Recognizing the role of automation for airports, IATA identified AV and robotics as a solution to increase efficiency to meet growing aviation demand (IATA, 2017). AGVT would get the equipment where it is needed on the ramp and near the airport. Robotics refers to more complex activities such as loading the cargo onto the aircraft; assessment of airside robotics is beyond the scope of this study. AGVT to support ramp and aircraft activities include aircraft pushback (on the ramp) and aircraft tug or tow. These are considered separate applications since aircraft pushback would typically be on the non-movement area and aircraft tug or tow to and from the runway C H A P T E R 4 Prioritized Airside Applications

42 Advanced Ground Vehicle Technologies for Airside Operations would encompass both the non-movement area and the movement area. Baggage carts and dollies for cargo would be similar, although one would support passenger service and the other cargo service; in both cases the carts and dollies are typically pulled behind a tug in current practice. The belt loader and container loader applications are also similar; both convey items into the aircraft from the ramp that makes them common culprits for aircraft damage. In all applications, this project addresses the technology for the equipment as a ground vehicle, and does not address the robotics that would be needed, in this case for the automated transfer of baggage or cargo into the aircraft. Catering trucks may include both low-lift vehicles and high- lift vehicles, and may present additional hazards since they may cause damage when being raised or lowered, in addition to potential damage due to movements on the ramp. A deicing vehicle may present similar risks (and may also be used for washing aircraft) and the fluid used may present hazards. An employee or passenger shuttle is used to transport people airside; this may include transportation from an aircraft to the terminal or between airport terminals. Although not a vehicle, jet bridges can utilize AGVT (e.g., sensors and control systems) to reduce the potential for damage and delays at the gate. Vehicles providing lavatory service and water carriage may have similar operating characteristics, although automation of the lavatory service has risks associated with the chemicals used and the pathogens, and the potable water supply for the aircraft is regulated by the EPA and FDA as well as the FAA. The refueling pump and refueling tanker may also have special regulatory considerations that need to be considered since they handle fuel. Wing walkers ensure obstacle clearance from the ground and communicate with hand signals and orange batons—AGVT could support these functions in a variety of ways to reduce ground damage. Airport Operations Activities to support airport operations may occur anywhere on the airside. Airport opera- tions include inspections and maintenance on runways and taxiways in the movement area, as well as vegetation management, wildlife management, and security checks in remote areas of the airfield. Routine maintenance and regular self-inspections are a key component for airport certification for commercial air service under 14 CFR Part 139, and are also important for general aviation (GA) airports that are not certificated under Part 139. Ramp and Aircraft Activities Airport Operations Aircraft pushback Construction inspections Aircraft tow or tug to and from runway Emergency response Baggage carts Escort vehicle Belt loader FOD detection and removal Catering truck Friction testing Container/ULD loader (cargo) Light inspection Dollies (cargo carts) Mowing Deicing Paved area inspection Employee or passenger shuttle (airside) Perimeter security Jet bridge RCAM determination Lavatory service Safety area inspection Refueling pump Signs and marking inspections Refueling tanker Snow and ice control Water carriage Wildlife management Wing walker Other Other Note: The evaluation considers the AGVT required for airside vehicle movement but not the robotics required to perform all elements of the task (e.g., loading the aircraft). Table 5. Candidate airside applications for AGVT presented to stakeholders.

Prioritized Airside Applications 43 Construction inspections ensure the safety of airport operations during construction and may include checks for the safe storage of construction materials, adequate construction barricades properly positioned and lit, and the monitoring of other potentially dangerous condi- tions. Emergency response may include technologies to support ARFF vehicles as well as other emergency response activities, and automation may enhance capabilities and reduce risks to humans when hazardous materials are involved. Escort vehicles accompany visiting vehicles (e.g., construction or engineering vehicles) and ensure security, safety, and compliance with security and ATC communication protocols. AGVT for FOD detection and removal may build on previous concepts of automated FOD detection, which has been proposed as a feasible and cost-effective solution but not widely utilized. Friction testing ensures that contaminants do not degrade aircraft braking capabilities. Regular light inspections are required and ensure runways and taxiways are visible to pilots. Mowing activities may be conducted on many acres of land far away from the movement area, and airfield implementation of automated mowing may leverage advances in agriculture. Paved area inspections must check for cracks and surface variations that may impair directional control. AGVT have been used to support perimeter security at Edmonton Airport in Canada (International Airport Review, 2017), securing the airport’s 7,000 acres by identifying damage to the fence, detecting holes and gaps under the fence, as well as human or animal activity. The runway condition assessment matrix (RCAM) is used to determine and communicate the impact of contaminants (such as snow) on operations; AGVT may be used to support this determination, as well as provide other snow and ice control activities, such as snow removal. Safety area inspections ensure that the areas around the runways and taxiways are free of obstacles and able to support an aircraft in the event of an excursion. Signs and markings inspections ensure that all signs and pavement markings are in good condition and have adequate retroreflectivity. Wildlife management activities that may be supported by AGVT potentially include hazing and elimination of nests and food sources. Candidate Technologies Candidate applications represent a broad range of airside activities and provide numerous potential opportunities for the integration of AGVT to improve airside operations. The candidate technologies that may be appropriate to support candidate applications are shown in Table 6 and discussed below. The level of automation associated with the candidate technologies shown in Table 6 varies. Automation levels are based on the SAE definitions described in Table 1. Safety assist tech- nologies utilize ADAS and represent L1 and L2 automation; examples include AEB and collision warnings. The driver is responsible for monitoring the environment when safety assist technologies are used. Automated operation with a safety driver would likely be L3 or L4 operations. During L3 operations (conditional automation), the automated system remains responsible for monitoring the environment and the driver must be ready to take control at all Safety assist technologies Automated operation with a safety driver Fully automated without driver Vehicle platoon with driver in lead Remote driver or operation Centralized control of vehicles Improved Human Machine Interface (HMI) Other Table 6. Candidate technologies presented to stakeholders.

44 Advanced Ground Vehicle Technologies for Airside Operations times. The ADS provides notice to the driver when they need to take control; however, there is some concern that a driver may not be able to respond rapidly enough to assess the situation and respond appropriately when control is shifted from automated operation to manual control during the L3 operation. The presence of a vigilant safety driver provides valuable capabilities for response to unusual situations that the ADS may not be able to correctly interpret. During L4 operations (high automation), the ADS is capable of performing all driving functions under certain conditions, although the safety driver may have the option to control the vehicle, or may be required to operate the vehicle in some domains. For example, to test and demonstrate the capabilities of AVs, it may be appropriate to operate an automated mowing vehicle as L4 (high automation) in remote locations of the airport, and operate as L3 (conditional automation) in the runway safety area. Similarly, automation levels may vary during different weather conditions or during different times of day, reflecting that it may be possible to utilize more automation at times when there are no scheduled commercial operations versus during hours when commer- cial flights are scheduled. L4 or L5 operations are fully automated without a driver. Operations would be considered L4 (high automation) if the automated operations are constrained to a limited geographic area, to specific hours of the day, or during certain weather conditions. Operations would be consid- ered L5 (full automation) when the system is capable of automated operations in all areas where it is needed, during any hours, and during all weather conditions. While the fixed boundaries of an airport limit the domain of operation, the complexity of operating rules (e.g., obtaining approval from ATC prior to entering the movement area) and the complexity of possible scenarios (e.g., interaction with a wide variety of vehicles, aircraft and ramp personnel) may present greater technical challenges than the roadway sector, where L4 may represent operations on a limited access highway. As technology progresses, a vehicle with L4 or L5 capabilities may still provide an option that allows the driver to control the vehicle, so a single vehicle could have different operating rules in different situations. Vehicle platoon with a driver in the lead reflects CV technologies, which have been tested during demonstration projects on roadways, at airports (e.g., the snowplows in Norway), and in agriculture. Platoon operation with a person in the lead vehicle may provide benefits since it combines the benefits of multiple vehicles with the physical presence of a person who can monitor operations, is ready to take over if needed, and can respond to any irregularities or obstacles. This technology could potentially be applied to a variety of equipment including baggage carts, snowplows, or mowing tractors. This technology does not fit explicitly into the SAE framework but it may be somewhat analogous to L3 since it there is a safety driver; however, the platooning vehicles are automated. Remote driver or operation provides the benefits of a person providing oversight and the ability to respond, but may allow more efficient operation since the equipment no longer needs to convey a person or ensure the safety of a person on the equipment. Remote operation may also allow a single person to monitor multiple pieces of equipment, increasing efficiency. This technology does not align with the SAE framework, and the most analogous level would depend on the degree of automation and the role of the remote driver or operation. In some cases, remote operation may require a person to operate the equipment but have automation that provides support, in which case this technology would share characteristics with L2. Remote operation may align with L3 operation, if the operation is mostly automated but requires a person to be ready to intervene, if needed. Remote operation could also align with L4 operation, if the system operates autonomously without human intervention and does not require a person to monitor the system during operation. Centralized control of vehicles may enhance coordination and reduce the amount of equip- ment needed (due to increased efficiencies). The increased efficiency could result in reduced

Prioritized Airside Applications 45 delay, and associated reductions in fuel consumption and emissions. Centralized control would often have people monitoring operations, however, during normal operations, computer algo- rithms would deploy vehicles for maximum efficiency. Initially, centralized control may be analogous to L3 or L4 operation, since the vehicles may require occasional intervention from people, but the system would identify when intervention is needed. In the future, centralized control may become more analogous to L5, as automation advances. Improved HMI refers to advancing airside operations through better dashboards that connect people to the equipment and systems they currently use. All of the other technologies will require HMI, but this technology as a standalone option could be implemented to improve the way that current technologies are used by personnel involved in airport operations and ramp and aircraft activities. In many cases, improved HMI would be analogous to L1 or L2 in that the driver or operator is still expected to control the system. However, the improved HMI would be expected to make control easier and more intuitive to reduce error and improve efficiency. Prioritization Criteria Prioritization of applications (Table 5) and technologies (Table 6) for more detailed evaluation was based on: • Input and feedback from airport stakeholders (This input included an online survey, one-on- one feedback, and feedback via participation at an industry conference session on ground operations in which the participants were aviation professionals, many with airlines, with a shared interest in airline ramp operations and safety. Additional information about stake- holder input is included in Appendix D. Additional input and feedback was obtained after the prioritization to ensure stakeholder feedback was reflected in the detailed evaluation and throughout the entire study), • Demonstrated interest by airports in an application as evidenced by demonstration projects and permanent deployments, • Demonstrated interest by the aviation and research community as evidenced by published articles and reports, and • Interest in a variety of technologies and applications (For example, at least one technology application for ramp and aircraft activities should be included in the prioritized list, and at least one technology application for airport operations should be included in the prio- ritized list). Input and general feedback about technologies and automation were documented, as was specific feedback regarding the specific technology applications. Stakeholders were asked to rank the top applications for ramp activities and/or airport operations based on their expecta- tion that it would improve airside operations. Stakeholders could choose to provide input for the ramp and aircraft activities and/or the airport operations activities, based on their area of expertise. Stakeholders had the opportunity to provide both quantitative feedback (e.g., rankings) and qualitative feedback (e.g., comments and discussion). Summary of Findings Input from Stakeholders Feedback from airport stakeholders obtained from the online survey is shown in Table 7, Figure 17, Figure 18, and Appendix D. For airport operations, FOD detection and removal, mowing, and snow and ice control were the most highly ranked applications. For ramp opera- tions, baggage carts, aircraft pushback, and aircraft tow or tug (to or from the runway) were the most highly ranked applications.

46 Advanced Ground Vehicle Technologies for Airside Operations Airport Operations Activities Ramp and Aircraft Activities FOD Detection and Removal Aircraft Pushback Mowing Baggage Carts Snow and Ice Control Aircraft Tow or Tug Perimeter Security Table 7. Highest ranked applications based on feedback from online survey. Figure 17. Airport and ramp operations applications survey results.

Prioritized Airside Applications 47 The technology that was preferred varied depending on the application. For FOD detection and removal, safety assist was of greatest interest whereas for mowing, full automation with no driver was of the greatest interest. The preferred technologies for the top ranked airport operations and ramp and aircraft activities are shown in Figure 18. Comments from the online survey and the conference session confirm that safety is impor- tant, and also identify that issues related to budgets and return on investment are important, as is the potential impact on the workforce. Demonstration Projects Automation on the airside is already being tested through demonstration projects and even deployments at airports worldwide. Projects include automated airport shuttle vehicles, auto- mated snowplows, and remotely controlled aircraft tugs. There will be more opportunities for partnerships and demonstration projects as AGVT advance not only in aviation, but also in other sectors, including the roadway sector, construction and mining, and at sea ports. Table 8 provides examples of demonstration projects and project deployments in aviation as well as example automation activities in other sectors. Published Articles and Scholarly Work Google Scholar was used to conduct a systematic literature search to investigate what AGVT have been studied in airside operations. A combination of search terms specifying operational Figure 18. Preferred technologies identified in stakeholder survey.

48 Advanced Ground Vehicle Technologies for Airside Operations environment, specific ground vehicle and/or application, SAE L1 to L2 specific technologies, and SAE L3 to L5 search terms were entered into Google Scholar, and results of specific searches are provided in Table 9. Those sources that were deemed relevant are provided in Appendix E. Search results were constrained to scholarly work and patents with publication dates within the last 5 years in order to assure that the findings were not out-of-date. Initial screening of records was based on title and abstract information, and final exclusion of records was based on predefined exclusion and inclusion criteria of being related to, or reasonably applicable to, use in an airside operations context. The sources listed in Appendix E are organized into 13 different categories: AGVT background, AGVT testing/validation/benefit measurement methods, automated taxi operations, automated mowing, automated pavement inspection/repair, automated snow/ice control, automated surveil- lance, driver/pilot assist, enabling technologies for AGVT, FOD detection/removal, improved HMI, platooning AGVT, and supporting infrastructure for AGVT. These sources are further organized by year of publication and then first author surname within each category. Automated, autonomous, remote control, and teleoperated mowing was a topic with many patents. Adding airport operational environment terms (i.e., “airport operations,” “airside Project Year Location Source Automated Snowplow 2018 Fagernes Airport Leirin, Norway (VDB) Airport Technology, 2018 2018 Winnipeg Richardson International Airport (YWG) CBC News, 2018 2019 Oslo Airport, Norway (OSL) Maronese, 2018 Automated Airport Shuttle 2018 Gatwick Airport (LGW) Gatwick Airport Press Office, 2018 2018 Brussels Airport (BRU) Brussels Airport, 2018 2018 Charles de Gaulle (CDG) Phelan, 2018 Automated Cargo 2018 London Heathrow (LHR) Air Cargo News, 2018 2018 Changi Airport (SIN) Park, 2018 Automated Jet Bridge 2017 Changi Airport (SIN) Lim, 2017 Automated Baggage Handling 2018 Hague Airport (RHA) International Airport Review, 2018 Automated Perimeter Security 2010 Ben Gurion International Airport (TLV) Estrin, 2010 2018 Edmonton Airport (YEG) Sarkonak, 2018 Automated Runway Paving 2010 John F. Kennedy Airport (JFK) For Construction Pros, 2010 Remote Aircraft Taxiing 2015 Frankfurt Airport (FRA) GreenAir Online, 2015 2018 Mumbai Airport (BOM) and New Delhi Airport (DEL) Gandhiok, 2018 2017 Heathrow Airport (LHR) LeFebvre, 2017 Table 8. Sample AGVT demonstration projects in aviation.

Prioritized Airside Applications 49 Search Terms Filters/Limiters applied Number of Records Retrieved Excluded after Screening Included automated OR autonomous AND "ground vehicles" AND "airport operations" OR "parking ramp" OR "passenger gates" OR "gate operations" OR "airside operation" 2013–2019 122 114 8 automated OR autonomous AND "baggage cart" OR "baggage truck" OR "cargo cart" OR "cargo truck" AND "airport operations" OR "parking ramp" OR "passenger gates" OR "gate operations" OR "airside operation" OR "terminal operations" 2013–2019 28 24 4 automated OR autonomous AND "catering cart" OR "catering truck" AND "airport operations" OR "parking ramp" OR "passenger gates" OR "gate operations" OR "airside operation" OR "terminal operations" 2013–2019 12 11 1 forward collision warning OR "automatic emergency braking" OR "collision avoidance" OR "blind-spot monitoring" OR "advanced driver assistance system" AND "ground vehicles" AND "airport operations" OR "parking ramp" OR "passenger gates" OR "gate operations" OR "airside operation" 2013–2019 25 23 2 automated OR autonomous OR "remote control" OR teleoperation AND mowing OR mower AND airport OR airside 2013–2019 862 855 7 automated OR "autonomous" OR "platoon" AND snow OR ice AND removal OR control AND "airside operations" OR "airport operations" 2013–2019 359 352 7 "FOD detection" OR "FOD removal" AND "automated" OR "autonomous" OR "safety assist" OR "human machine interface" 2013–2019 95 84 11 automated OR "autonomous" AND "aircraft taxiing" OR "aircraft towing" OR "aircraft pushback" AND "airport operations" OR "airside operations" 2013–2019 119 106 13 Table 9. Search terms used to investigate scholarly work related to AGVT. operations”) resulted in a much more constrained search with fewer relevant results—so search terms were abbreviated to airport and airside. This was also true of ice and snow removal (for pavement) search results. Both mowing and snow and ice removal are widely used in other sectors (e.g., roadways) and the technologies have advanced due to the large market; the tech- nology advancements for these applications can benefit airport operations. Although its application is limited to airfields, FOD detection had a number of scholarly publications. Automated aircraft taxiing, aircraft pushback, and aircraft towing are also areas of interest, with multiple modeling, simulation, and conceptual studies to date (e.g., Kocks et al., 2014; Morris et al., 2015; Quinet, 2017). Scholarly work has addressed not only ground vehicle applications such as mowing and ice control, but also technologies for ATC and ramp control. One research study presented an ATC tower simulator for ground operations (Chua et al., 2015); this may be useful to simulate,

50 Advanced Ground Vehicle Technologies for Airside Operations Airside Applications Proposed Technology Ramp Activities Baggage carts Safety assist Aircraft pushback Remote from ramp, Automated with driver Aircraft tow or tug to and from runway Remote from cockpit, Automated with driver Airport Operations FOD detection and removal Safety assist,1 Automated with driver Mowing Centralized, Automated with no driver Snow and ice control Platoon with driver in lead, Remote operation Perimeter security Automated with no driver 1Safety assist for FOD detection and removal will include evaluation of ADS-B transponders for the airport ground ops vehicle. Table 10. Airside applications prioritized for further evaluation. test, and validate the use of AGVT use prior to actual deployment. Many search results fell under the development and testing of enabling technologies on which AGVT might rely (e.g., Coyle et al., 2016). Many of these results were patents. LiDAR point cloud-based systems were used in a variety of ways including FOD detection (Mund et al., 2015), risk mitigation (Mund et al., 2014), object classification (Mund et al., 2016), and monitoring taxiing and landing aircraft (Koppanyi and Toth, 2018). List of Prioritized Applications Based on the input from stakeholders, assessment of demonstration projects, and a review of published articles and scholarly work, seven proposed airside applications were identified and approved by the panel for further evaluation; the applications prioritized for further evaluation are shown in Table 10.

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Recent advancements in automated and advanced driving technologies have demonstrated improvements in safety, ease and accessibility, and efficiency in road transportation. There has also been a reduction in costs in these technologies that can now be adapted into the airport environment.

The TRB Airport Cooperative Research Program's ACRP Research Report 219: Advanced Ground Vehicle Technologies for Airside Operations identifies potential advanced ground vehicle technologies (AGVT) for application on the airside.

Appendices B Through S are online only. Appendix A, on enabling technologies, is included within the report.

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