Urban Air Mobility: An Airport Perspective (2023)

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59   Planning Strategies for Integrating Urban Air Mobility into Airports Effective planning for AAM will be essential for airport practitioners to prepare and plan for changes in air travel and multimodal trans- portation integration. This chapter provides information and planning tools to assist with this effort from an airport planning perspective, including • Applicable Policies and Standards, • Policymaking Efforts, • Facilities, • Utilities and Support Infrastructure, and • Corridor Planning. 6.1 Applicable Policies and Standards Vertiport Planning and Design According to the FAA, an AC on vertiport design is under development and should be published in 2024. An engineering brief may be released in 2022 as interim guidance. It will consider the use of existing infrastructure and the development of new purpose-built vertiports. It is expected that the AC will address the following items: • Landing area design and layout • Approach/departure paths • Load-bearing requirements • Electric propulsion and charging stations • Safety requirements for batteries and other hazardous materials • Noise requirements • Rescue and firefighting requirements • Vertiport automation In the meantime, vertiports for UAM should be planned according to the overall approach described in FAA AC 150/5070-6B: Airport Master Plans as well as the general requirements of AC 150/5390-2C: Heliport Design (FAA 2005b; FAA 2012). However, additional con- tent may be required to develop specific approaches to adapt these standards to atypical aerial vehicles. For instance, conservatively assuming that eVTOLs have the same per- formance as conventional helicopters, AC 150/5390-2C standards may apply to helicopters with only one main rotor axis, while most eVTOLs have several main rotors and non-typical configurations. C H A P T E R 6 Key Points • How to plan for UAM • Policies and standards • Utilities and support infrastructure • Corridor planning

60 Urban Air Mobility: An Airport Perspective STOLport Planning and Design The International Civil Aviation Organization (ICAO) defines STOLports as “unique airports designed to be served by airplanes that have exceptional short-field performance capabilities.” ICAO Doc 9150 “Stolport Manual” states that “for the purposes of this manual, the stolport design aeroplane is assumed to be an aeroplane that has a reference field length of 800 m [about 2,600 ft.] or less” (ICAO 1991). However, facilities with runways shorter than 5,000 feet are sometimes considered STOLports. Billy Bishop Toronto City Airport, Canada (2,460 feet and 3,988 feet) and London City Airport, United Kingdom (4,948 feet) are considered the busiest urban STOLports in the world. London City Airport started commercial operations in 1988 with a 3,543-foot-long runway and a 7.5-degree approach path—later expanded to nearly 5,000 feet and reduced to 5.5 degrees. Current STOLport planning and design in the United States follow the standards and recom- mendations in applicable ACs, and in particular AC 150/5070-6B: Airport Master Plans and AC 150/5300-13A: Airport Design (FAA 2005b; FAA 2014). Other Advisory Circulars on Airport Planning and Design The FAA publishes ACs to provide guidance for compliance with airworthiness regulations, operational standards, and grant requirements. Table 12 represents a selection of existing ACs that planners should consider when integrating future AAM vehicles into airports and aviation systems. Title 14 Code of Federal Regulations Part 77 on Imaginary Surfaces To preserve aviation activity and navigable airspace from urban development, Title 14 of the Code of Federal Regulations (CFR) Part 77 §23 defines imaginary surfaces to identify potential obstructions off-airport/off-heliport. These standards apply to an airport or heliport available for public use, a future airport under construction of which the FAA has received actual notice that it will be available for public use, an airport operated by a federal agency or the Department of Defense, or an airport that has at least one FAA-approved instrument approach. These regula- tions are not applicable to private airports or heliports, which could be the case for some future vertiports. The protection of the AAM activity and vertiport airspace for private infrastructure will require other legislation. These regulations state that all proposed construction projects or existing facility improve- ments must be reported to the FAA through a Notice of Proposed Construction or Alteration (FAA Form 7460-1) 45 days before the first day of construction. For each obstruction, the FAA will conduct an aeronautical study to • Assess the effects of the construction on navigable airspace and operation procedures, • Evaluate the potentially hazardous effect on air navigation, • Identify mitigating measures (for example, appropriate marking or lighting recommendations) to enhance the safety of air navigation, and • Notify the aviation community of the construction and the potential obstructions that will affect the airspace, including chart revisions if necessary, through a Determination of Hazard to Air Navigation. Although these imaginary surfaces are designed to identify potential obstructions, 14 CFR Part 77 does not empower the FAA, or airports, to enforce imaginary surfaces and prevent off-airport/heliport construction projects that could compromise these surfaces. However, the enforcement of non-obstruction of Part 77 imaginary surfaces can be enabled through local

Title AAM Considerations AC 150/5020-1: Noise Control and Compatibility Planning for Airports Noise control and compatibility planning reduce existing non-compatible land uses and prevent future non-compatible land uses around airports. Federal Aviation Regulation Part 150 Airport Noise Compatibility Planning (Part 150), which implements portions of Title I of the Aviation Safety and Noise Abatement Act of 1979, guides noise compatibility planning efforts. Part 150 set a standard metric for measuring noise exposure, the Day-Night Average Sound Level, and established a voluntary program governing the development of airport noise exposure maps and noise compatibility programs. Note on AAM: Noise emissions of AAM vehicles—mostly electric or hybrid-electric aircraft— will be lower than with current aircraft. AC 150/5060-5: Airport Capacity and Delay Airport capacity and aircraft delay depends on fleet mix and air traffic control practices and are specific to each airport. Airport planners and designers calculate airport capacity and aircraft delay based on typical hourly demand expected to occur on a weekly basis. Calculations depend on a variety of inputs, including aircraft mix, number, and type of gates, gate mix, and gate occupancy times, among other inputs. Note on AAM: AAM vehicles are slower than turbojet aircraft, potentially affecting airport capacity and delay if using existing air routes or runways. AC 150/5070-6B: Airport Master Plans Master Plan Update process and show existing and future airport facilities, requiring approval by the FAA to receive federal funding. Note on AAM: The master planning process should consider the specific facility and space requirements of AAM based on realistic aviation activity forecasts supported by trends and/or flight operator commitments. AC 150/5070-7: The Airport System Planning Process Airport system planning assesses the performance and interaction of an aviation system, including the interrelationship of airports within the system. It considers state and regional goals related to transportation, land use, and the environment. Elements of the process are intended to identify how the aviation system can meet existing and future demand. Note on AAM: Integration of AAM vehicles into airport system planning processes provides an important consideration for future studies to enable the effective use of federal and local aviation resources. AC 150/5300-13B: Airport Design Airport design standards ensure a safe, efficient, and economically sound United States airport system. Airports, including both airside and landside infrastructure, should be designed to accommodate the range of size and performance characteristics of aircraft anticipated for use at airports and their fueling/charging needs. Note on AAM: AAM requires specific support infrastructure and equipment (e.g., charging infrastructure and hydrogen refueling infrastructure) that should be taken into consideration in airport design. AC 150/5390-2C: Heliport Design Helicopters do not only operate on runways at airports but also at specific facilities named heliports. These facilities are designed based on specific design standards to ensure safe helicopter operations, for a range of the size and performance characteristics of helicopters anticipated for use at the heliports. There are different categories of heliports depending on the operation types, which involve different requirements. Note on AAM: Because of the specificities of most electric VTOLs that are not typical on conventional helicopters (e.g., multiple rotors and large wingspans), heliport design standards may need to be adjusted when developing facility requirements for these emerging vehicles. Guidance on vertiport design is under development with the FAA. AC 150/5325-4B: Runway Length Requirements for Airport Design Determining recommended runway lengths relies on a five-step process. The first step involves identifying the critical design airplanes that will make regular use of the runway for a planning period of at least 5 years. Step two requires determining which airplanes need the longest runway length based on maximum takeoff weight (MTOW). Small airplanes with MTOW of 12,500 pounds or less are categorized based on approach speeds and passenger seating. Note on AAM: It should be expected that many AAM vehicles will have STOL and VTOL capabilities. For STOL and VTOL operations at airports, a separate STOL runway or FATO/ touchdown and liftoff (TLOF) areas can be considered to accommodate these vehicles. AC 36-1H: Noise Levels for U.S. Certificated and Foreign Aircraft Noise level data for certificated aircraft categorizes aircraft into various “stages.” Noise certification ensures that the latest available noise reduction technology, deemed safe and airworthy, is included in aircraft design to reduce noise impacts on communities. Note on AAM: AAM vehicles are expected to feature noise levels significantly lower than conventional aircraft. Data on electric and hybrid-electric aircraft noise levels in flight will have to be incorporated into future FAA noise models. Long-term airport development and planning are governed by individual airport master plans. Master plans are intended to develop airports safely and efficiently by looking toward the future to dictate development and planning needs. Master plan studies include environmental considerations, facility requirements, airport layout plans, facilities implementation plans, and financial feasibility analyses, among other components. They require an inventory of existing conditions, including utility infrastructure and demands such as power needs, to inform the quantification of future utility loads. Airport Layout Plans (ALPs) are a product of the Table 12. FAA advisory circulars and AAM impact assessment.

62 Urban Air Mobility: An Airport Perspective regulations or ordinances. For instance, Franklin County, Washington, amended its Code of Ordinances to prevent any obstructions of Tri-Cities Airport’s Part 77 surfaces (Chapter 17.79 – Airport Zoning, Title 17 – Zoning, Franklin County Code). Sonoma County, California, has approved an Airport Land Use Plan that states that “no structure, tree, or object shall be permitted to exceed the height limits established in accordance with Part 77, Subpart C, of the Federal Aviation Regulations (FAR)” (Chapter 8 – Airspace Policies, Sonoma County Airport Land Use Plan). Authority of the FAA over On-Airport Land Use Section 163 of the FAA Reauthorization Act of 2018 (H.R. 302) defines the limits of the FAA’s authority over on-airport land uses. The bill clarifies the responsibilities of the FAA. The FAA may not regulate the acquisition, use, or disposal of land by an airport and the facili- ties on this land, except in the following cases: • To ensure the safety and efficiency of airport operations and/or the safety of people and property on the ground • To guarantee the fair market value of the land • Any land or facility acquired with federal funding While Section 163 stipulates that the FAA ALP approval authority is limited to the portions of the airport property that affect the safety of airport operations, people, and property on the ground, airports are still subject to revenue use and diversion restrictions set by the FAA. Land-Use Compatibility Plans Airport land-use compatibility plans (ALUCP) can be developed to address compatibility around an aviation facility. In California, counties with public-use airports are required to prepare an ALUCP under the supervision of an airport land-use commission. The purpose of such a plan is to ensure the safe and efficient operations of aircraft and the safety of people and property on the ground related to aircraft operations. The 2011 California Airport Land Use Planning Handbook was prepared to provide guidance regarding land use, identify requirements and procedures in the preparation of ALUCP, and define exemptions if applicable (California Department of Transportation 2011). An ALUCP allows local governments and airports to develop land-use plans that consider 14 CFR Part 77 requirements, U.S. Standard for Terminal Instrument Procedures, and provisions for protecting one-engine-inoperative requirements for air carriers. In 2015, Santa Clara County developed a specific ALUCP for heliports, named the Heliport Land Use Compatibility Plan. AC 150/5190-4A: A Model Zoning Ordinance to Limit Height of Objects Around Airports and Draft AC 150/5190-4B: Airport Land Use Compatibility Planning raise awareness of the importance of compatible land-use planning and provide guidance (FAA 1987; FAA 2021). The latter provides the 2011 California Airport Land Use Planning Handbook as a case study (California Department of Transportation 2011). These documents can help airport practitioners, and especially local governments and the local aviation community, develop compatible planning documents and promote compatible land use with the emergence of new aviation facilities and usages with AAM. There are few cases where the federal authority prevailed over the local jurisdictions on matters of off-airport land use. ACRP Legal Research Digest 5: Responsibility for Implementation and Enforcement of Airport Land-Use Zoning Restrictions and ACRP Legal Research Digest 14: Achieving Airport-Compatible Land Uses and Minimizing Hazardous Obstructions in Navigable Airspace identify these exceptions regarding noise, height, and environmental issues around

Planning Strategies for Integrating Urban Air Mobility into Airports 63 the airport (Cheek 2009; Waite 2012). For instance, in 1973, in City of Burbank v. Lockheed Air Terminal, Inc. (411 U.S. 624, 93 S. Ct. 1854, 36 L. Ed. 2d 547), the Supreme Court invalidated the city ordinance forbidding aircraft to serve a major airport at night because of aircraft noise. The decision was based on the fact that the Federal Aviation Act and the subsequent Noise Control Act prevailed, by virtue of federal supremacy, over local regulation on authority over the skies. Local Codes and Ordinances on Heliports/Vertiports Several local governments, especially some cities and municipalities, have issued local rules to ensure public safety, protect heliports’ airspace, and mitigate noise impacts on the surround- ing community. Cities and other relevant local jurisdictions can issue land-use ordinances and amend zoning maps to regulate and protect heliport/vertiport airspaces, as well as prevent encroachment to mitigate noise and preserve safety. Also, cities across the country have already enacted ordinances to create a heliport/vertiport approval process and protect their airspace in addition to 14 CFR Part 77 §23 on heliport imaginary surfaces. Some examples include the following: • Los Angeles, California. In 2015, the city passed an ordinance regarding UAS (Section 56.31, Article 6, Chapter V, Los Angeles Municipal Code) that aims to regulate UAS operations, especially in the vicinity of airports. • San Diego, California. The municipal code of San Diego has provisions regarding airspace around heliports in Section 68.0209—Heliport and Helistop Regulations and Section 68.0210— Elevated Heliport and Helistop Regulations. • Orlando, Florida. The city of Orlando amended its code to include provisions on vertiports (Chapter 58 – Zoning Districts and Uses, Part 4P. – Vertiports). The section provides a definition of a vertiport, the standard requirements for the approval of vertiports, and other procedural requirements. Compatibility of Building and Construction Codes with Vertiport Opportunities Local building codes may feature requirements for heliports and other aviation facilities. For instance, Section 412.7.4, Rooftop heliports and helistops of the 2014 Construction Codes of New York City specifies that rooftop helicopter facilities must comply with the National Fire Protection Association, Standard for Heliports and the New York City Fire Code. Los Angeles requires any building with a height of 120 ft. above the lowest level of fire depart- ment access to provide on its rooftop an emergency helicopter landing facility, as mentioned in Section 2007.9, Emergency Helicopter Landing Facility (EHLF) for High-Rise Buildings, of the Title 32 – Fire Code of Los Angeles County. Such regulation can promote and accelerate the introduction of UAM operations in Los Angeles, since several vertical structures are helipad- ready, facilitating their adaptation into vertiport assets. Similar laws used to exist in other cities, including New York City, which required provisions for helipad facilities on high-rise buildings. Many were repealed after the crash of a Sikorsky S-61 on the top of the Pan Am Building (now the MetLife Building) in Manhattan. However, high-rise buildings that were built before the 1970s may be helipad-capable, facilitating the implementation of a network of UAM facilities. Vertiports might need to implement 5 to 50-megawatt (MW) charging infrastructures to support VTOL operations. Electrical equipment and infrastructure will need to comply with building codes. Most jurisdictions have adopted the International Building Code or have developed local standards such as the California Building Code. Other codes and regulations and industry

64 Urban Air Mobility: An Airport Perspective documents are applicable to building electrical equipment, including those that address energy saving, sustainability, and power resiliency. For instance, New York City has its own electrical code. The city also requires buildings to comply with the 2020 New York Energy Conservation Code. Standards of the Institute of Electrical and Electronics Engineers provide industry stan- dards and practices for domains such as the power resiliency of building equipment. Some AAM vehicles will be powered by liquid or gaseous hydrogen turned into electricity via fuel cells. Building codes already typically regulate the storage of flammable and combustible gases. For instance, the California Building Code provides requirements regarding the storage, use, and handling of compressed gas (Chapter 53, Compressed Gases), especially for the design, arrangement, and freeze protection of storage devices. With the emergence of aerial air mobility and the hydrogen economy, new engineering and safety issues may arise and lead to a revision of these codes to address new usages of hydrogen in or on buildings. Further discussions on standards related to the accommodation of electric aircraft and hydrogen technologies are available in ACRP Research Report 236: Preparing Your Airport for Electric Aircraft and Hydrogen Technologies. Aviation Security Requirements Transportation Security Regulations are codified in Title 49 CFR, Chapter XII – Transportation Security Administration, Department of Homeland Security, Parts 1500 through 1699. Aviation stakeholders involved with AAM might be concerned by the regulations listed in Table 13, includ- ing Part 135 air carriers (as aircraft operators) and vertiport operators. According to 49 CFR §44901, all screening of passengers and property at United States airports must be supervised by uniformed TSA personnel, except if the airport operator is approved to take part in the screening partnership program as provided under §44920. Checked baggage must be screened at all airports by a system—an explosives detection system or, if not available, an alternative means. Alternative means may include one or more of the following: a bag-match program, which ensures that any checked baggage is placed aboard an aircraft only if the passenger owning the baggage is aboard; manual search; canine explosives detection units in combination with other means; or other means and technology approved by TSA. Transportation Security Regulation Details 49 CFR Part 1520 Refers to the protection of sensitive security information. It provides standards on the maintenance, safeguarding, and disclosure of records and information that TSA has determined to be Sensitive Security Information. 49 CFR Part 1540 Defines the general rules of civil aviation security applicable to airport operators, air carriers, and passengers. Regulations regarding the security responsibilities of passengers and other individuals related to air operations are listed. 49 CFR Part 1542 Provides airport security criteria, procedures, operations, and contingency measures. 49 CFR Part 1544 Defines the security standards applicable to aircraft operators. 49 CFR Part 1550 Describes the regulations for aircraft security under general operating and flight rules. Under this, TSA is authorized to perform inspections or tests of aircraft. Each aircraft operator has to provide evidence of compliance with this part and its security program or security procedures, including copies of records. 49 CFR Part 1554 Refers to regulations of aircraft repair station security that include security measures, security directives, compliance, and enforcement. Table 13. Main civil aviation security rules.

Planning Strategies for Integrating Urban Air Mobility into Airports 65 To date, general aviation airports—defined in 49 CFR §47102 as public-use airports located in a state that does not have scheduled service or have scheduled service with less than 2,500 annual passenger boardings—have not been subject to TSA regulations, with the notable exception of the general aviation facilities located within the Flight-Restricted Zone protecting Washington, D.C. However, according to 49 CFR §44901(k), TSA is mandated to develop a standardized threat and vulnerability assessment program for general aviation airports and to implement this program at individual general aviation airports on a risk-managed basis. According to the 2007 ACRP Synthesis 3: General Aviation Safety and Security Practices, general aviation airports and Fixed-Base Operators (FBOs) have a variety of resources for developing their own need-based security plan, including TSA guidelines, state DOT regulations, and the American Association of Airport Executives (Williams 2007). Once the security plan is established, airports typically share their plans with local law enforcement, their FBOs, the local fire department, the TSA, and federal law enforcement agencies. For risk assessment purposes, TSA has developed vulnerability assessment tools as part of the Security Guidelines for General Aviation Airports document (TSA 2004). Additional guidelines for general aviation security can be found in the 2017 TSA Security Guidelines for General Aviation Airport Operators and Users, which provides information about general aviation airport security enhancement, security procedures, security awareness training, airport watch programs, and risk-based assessment (TSA 2017). Further guidance on airport security for terminal planning and design is available in ACRP Research Report 25: Airport Passenger Terminal Planning and Design, TSA’s Checkpoint Design Guide, and AC 150/5360-13A: Airport Terminal Planning (Landrum & Brown et al. 2010; TSA 2012; FAA 2018b). Aircraft operators carrying passengers or cargo are subject to security requirements listed in Table 13. Regulations in 49 CFR §1544.101 detail the applicability of these requirements and the need for aircraft operators to adopt and implement a security program. Different requirements apply to aircraft operators depending on the type of operations and the seating configuration of the aircraft. Because the majority of vehicles under development for providing AAM services have a seating capacity of fewer than 19 seats and a MTOW of less than 45,500 kg, most aircraft operators operating scheduled passenger, public charter passenger, or all-cargo services for AAM might be required to adopt and implement one of the following programs: • A “full program” per 49 CFR §1544.101(a) if the aircraft enplanes from or deplanes into a sterile area • A “12-5 program” per 49 CFR §1544.101(e) if the MTOW is more than 12,500 pounds, and the aircraft operator is not under a full, partial, or full-cargo program Many operations of AAM may not trigger a security plan per 49 CFR §1544 (e.g., a four- passenger, public charter flight operated with a small electric aircraft that has a MTOW of 5,000 pounds or an all-cargo flight operated with a UAS that has a MTOW of 1,000 pounds between two general aviation facilities without defined sterile areas). They might not be required to adopt and implement a TSA security plan unless one of their operations is concerned by 49 CFR §1544. AAM operations from and to commercial airports with a sterile area might fall under the scope of 49 CFR §1544.101(a). It is reasonable to assume that passengers of AAM flights will enplane and disembark from sterile areas when flying from a commercial service airport, even when a separate terminal exists for RAM, with the exception of vertiports outside the aircraft operating area (AOA). There is less certainty regarding operations from a vertiport separated from the main airport facilities and AOA (e.g., on the rooftop of a parking garage) where the TSA elects to not designate a sterile area.

66 Urban Air Mobility: An Airport Perspective At small general aviation facilities—including vertipads, based on the type of service provided (on-demand flights with small, light aircraft from potentially non-sterile areas), the typical air- port passenger screening process might not be warranted. However, AAM service providers and their aircraft operators, in coordination with the TSA, might elect to implement security measures going beyond the existing regulations. The regulations might evolve to address the specificities of these operations. 6.2 Policymaking Efforts on Advanced Air Mobility Planning Ongoing Policymaking Efforts and Congressional Awareness of Policy Needs In February and March 2021, two proposals for an Advanced Air Mobility Coordination and Leadership Act (H.R.1339 and S.516 – 117th Congress) were introduced into Congress. A working group under the leadership of the DOT to “plan for and coordinate efforts related to the physical and digital security, safety, infrastructure, and federal investment necessary for maturation of the AAM ecosystem in the United States” was proposed to be created under these bills (S.516). The group would include the different stakeholders of the industry, including aviation stakeholders, electric utilities, energy providers, market operators, and representatives of the major federal agencies (e.g., FAA and NASA). The U.S. House Committee on Transpor- tation and Infrastructure unanimously approved the bill H.R.1339 on July 30, 2021, and this bill now needs to be approved by the full House. The objective of the working group is to prepare and submit to Congress a report featuring an AAM national strategy that includes the following: • Recommendations regarding the safety, security, infrastructure, air traffic concepts, and other federal investment or actions necessary to support the evolution of early AAM to higher levels of activity and societal benefit • A detailed plan describing the roles and responsibilities of each federal agency necessary to facilitate implementing these recommendations Local Initiatives Several states are starting to take an interest in facilitating the emergence of AAM locally. Working groups and studies are being conducted to evaluate the potential benefits of AAM for the local economy and communities, explore options for policies that could enable or facilitate the development of AAM, and integrate AAM considerations into statewide transportation system planning. They include the following: Washington Electric Aircraft Feasibility Study. In 2020, the aviation division of the Wash- ington Department of Transportation (WSDOT) published a report, Washington Electric Aircraft Feasibility Study, to pave the way for the introduction of electric aircraft in the state (WSDOT 2020). The study developed a roadmap for integrating electric aviation based on the following considerations: • Infrastructure requirements necessary to facilitate electric aircraft operations at airports • Potential economic, environmental, and other public benefits • Potential future aviation demands catalyzed by electric aircraft • Workforce and educational needs to support the industry • Available incentives to industry to design, develop, and manufacture electric aircraft • Impacts on Washington’s existing multimodal transportation network

Planning Strategies for Integrating Urban Air Mobility into Airports 67 Colorado Department of Transportation. The Colorado Aeronautical Board and Colorado DOT have held meetings with electric aviation stakeholders and are considering conducting an electric aircraft charging infrastructure study to assess the needs of the Colorado aviation system. The project would address the following: • An overview of the existing situation of the small electric aircraft industry • Potential options for charging infrastructure and capacity needed by general aviation aircraft • An inventory of the existing electrical service for four selected general aviation training intensive airports (Centennial Airport, Rocky Mountain Metropolitan Airport, Northern Colorado Regional Airport, and Colorado Springs Airport) and an analysis of the capability of said service to support electric aircraft activities • An overall cost estimate for airport electrical service upgrades to accommodate the potential electric aircraft demand and follow-up analysis and evaluation of sources of funds for the upgrades • An analysis of potential funding mechanisms that could be implemented by airports, FBOs, and aircraft operators to fund the capital and life cycle costs of electric aircraft charging infrastructure Texas Legislature Initiative. In July 2021, the Texas Senate passed bill TX SB763 promoting UAM and creating a UAM advisory committee within the Texas Department of Transportation to assess current state law and identify any potential changes needed to facilitate the development of UAM operations and infrastructure in Texas. The Dallas-Fort Worth area already announced its intention to become a test location in 2025. Moreover, the North Central Texas Council of Governments has partnered with NASA to integrate AAM into the metropolitan transportation system. These efforts will concentrate on studying cargo-carrying drones and automated air taxis during a series of at least four workshops. City of Orlando Urban Air Mobility Initiative. In 2020, the city of Orlando, Florida, published a white paper on Urban Air Mobility Overview (Orlando 2020). Orlando wants to become one of the first United States cities to accommodate eVTOL flights. The purpose of this white paper is to inform residents about UAM opportunities, potential congestion, and economic benefits and to describe the challenges. The following four main areas were identified by the city: • UAM local and state regulations • UAM infrastructure • UAM flight regulations • Public acceptance The study considered potential routes and vertiports. To continue this effort, the city offered a $1 million tax rebate to Lilium over the next 9 years if it invests in the area for developing its first United States test vertiport to contribute to the development of UAM. According to the city of Orlando, this partnership could create about 100 jobs, and the facility could generate an additional $1.7 million in economic impact over a 10-year period. 6.3 Advanced Air Mobility Planning Process A planning process is proposed to facilitate the integration of AAM into existing airports and aviation facilities. Figure 11 depicts the proposed process. First and foremost, an airport operator needs to identify and bring together the stakeholders involved in future AAM operations into an AAM working group. The members of this work- ing group might vary from one airport to another, depending on their operating model. This

68 Urban Air Mobility: An Airport Perspective working group will drive the AAM implementation effort, providing a framework for collabora- tion, identifying the operational and infrastructure needs, and developing the required proce- dures and plans. The AAM working group can be merged with the electric aircraft working group detailed in ACRP Research Report 236: Preparing Your Airport for Electric Aircraft and Hydrogen Technologies. The AAM implementation effort should adopt the principles of Airport Collaborative Decision Making (ACDM) outlined in ACRP Research Report 229: Airport Collaborative Decision Making (ACDM) to Manage Adverse Conditions (Bris et al. 2021). At airports with an ACDM organization following the guidance of ACRP Research Report 229, the AAM working group can be a technical subgroup of the ACDM roadmap. The operating model of the services provided—with regard to the airport interface—needs to be discussed at this point because it will have a major impact on the planning of AAM facilities and for AAM operations, including the following: Figure 11. AAM planning process at airports.

Planning Strategies for Integrating Urban Air Mobility into Airports 69 • Air taxi/public charter operations. Most UAM and UAS deliveries might operate as air taxi/public charter services. They will use AAM vehicles with a small passenger capacity (two to six passengers typically), and their operations will feature characteristics of both air taxis and ground TNCs. VTOL and STOL aircraft will mostly fulfill these missions. • Scheduled operations. Most RAM might operate as scheduled services. They will typically use medium-size AAM vehicles with a passenger capacity of fewer than 19 seats. STOL and CTOL aircraft will mostly fulfill these missions. ACRP Research Report 144: Unmanned Aircraft Systems (UAS) at Airports: A Primer provided infor mation about UAS and their potential use and impact on airports (Neubauer et al. 2015). Creation of the Advanced Air Mobility Working Group The success of AAM implementation and integration into existing airport operations will require strong collaboration between the different stakeholders that would be involved or affected by AAM operations. This collaboration will allow the stakeholders to plan for changes required to accommodate AAM based on a clear understanding of their facility and operational requirements. Potential stakeholders might include the following: • Airport operator • Prospective AAM providers, air freight companies, and their flight operators • Representatives of existing flight operators (including the general aviation community) • Aircraft rescue and firefighting • FAA Airport District Office and Airport Flight Standards • Air traffic control tower • Ramp control tower (if any) • Aircraft ground support providers • FBOs • Utility providers and hydrogen suppliers • MRO operators • Ground transportation (such as TNCs) The airport operator is in the best position to coordinate all discussions of the AAM working group because of its role and interface with the different areas, functions, and stakeholders of an airport. ACRP Research Report 229: Airport Collaborative Decision Making (ACDM) to Manage Adverse Conditions provides extensive guidance on how to create a collaborative working group, identify individual stakeholders, secure executive buy-in, and make decisions (Bris et al. 2021). Coordination with Communities, Local Governments, and Planning Organizations In parallel with the process described above, non-aviation stakeholders should be engaged. The AAM working group should collaborate with local governments and MPOs to discuss land-use compatibility and integration of AAM into existing plans to better understand the potential impacts on communities, discuss the AAM infrastructure and utility needs, promote multi- and inter-modality, and consider the role of AAM in the overall transportation planning process. AAM operations will warrant public involvement programs at some airports, especially smaller general aviation facilities where AAM may significantly increase the aviation activity and traffic on the ground. Generally speaking, public outreach is a best practice when implementing major changes, regardless of their output. AAM will enhance the accessibility and connectivity of communities. It can create local jobs and economic opportunities. The environmental footprint of electric aircraft is significantly

70 Urban Air Mobility: An Airport Perspective smaller than that of conventional aircraft. Noise levels are expected to be dramatically lower, and the impact on air quality should be non-significant because flights generate zero greenhouse gas emissions. However, AAM may increase the activity of smaller airports, creating more flights and ground traffic at aviation facilities that may be subject to encroachment. These effects should be assessed and analyzed to help planners make decisions and develop a balanced approach that mitigates adverse impacts and benefits local communities. Involving communities in this planning process will increase the social acceptance of AAM. Being transparent about future undesirable impacts will build trust with the public and find acceptable mitigation with local residents. Studies on the social acceptance of AAM have started to emerge. They provide meaningful information on how citizens consider these new mobility opportunities for their communities against the negative externalities of such operations. In May 2021, the European Union Aviation Safety Agency published a Study on the Societal Acceptance of Urban Air Mobility in Europe that was conducted to identify concerns and expectations of European citizens regarding UAM (EASA 2021). Through interviews, surveys, a literature review, and market assessments, the report shows that the public has a good attitude toward UAM, especially when there were presented case studies showing benefits to the community (medical or emergency transportation or connecting remote areas). The European public seems concerned mostly about the safety aspects and noise. Although noise from AAM vehicles could be lower, the pitch and tone of the noise differ from usual urban sounds. Describe the AAM Operational Model The working group should work to define and understand the AAM operations expected at the airport, from the curbside to the airspace. This includes a list of the services that will be provided to passengers, an estimate of the future passenger and aviation activity, an inventory of the types of aerial vehicles expected and their requirements, and a description of landside and airside operations. The latter should note, for instance, if mobility-as-a-service (MaaS) will be provided—a list of the ground transportation modes and providers that will be included in the offer, as well as the relationship between the different stakeholders (e.g., if the AAM provider will be operating its own aerial vehicles or if operations will be contracted with a separate aircraft operator). Determine Advanced Air Mobility Requirements The following facility requirements are determined based on the expected AAM activity and the description of the AAM operational model: • Landside requirements include the following: – Ground access and curbside requirements to accommodate the new passenger demand, including the ground transportation partners that may be combined with AAM in the MaaS offer • Terminal requirements include the following: – Passenger accommodations from the curbside to the gate (Landrum & Brown et al. 2010; Intermodal Logistics Consulting et al. 2017) – Amenities and concessions, including the “signature experience” expected or demanded by the AAM providers – Security requirements, especially at general aviation facilities that do not require compre- hensive security plans – Airline support facilities

Planning Strategies for Integrating Urban Air Mobility into Airports 71 • Airside requirements include the following: – Gate facilities – Both UAM and RAM may prefer simplified gate facilities enabling short turnaround time features such as nose-in/nose-out stands and short-distance pedestrian paths from the holdrooms. – Recharging/refueling requirements – This is a major difference from conventional avia- tion because most AAM aerial vehicles will have electric and hybrid propulsion systems powered by batteries or hydrogen fuel cells. – Ground handling services that are electric aircraft capable. Develop Advanced Air Mobility Alternatives and Select Preferred Alternative The next step is to develop AAM alternatives to meet the facility’s requirements. At airports with excess airfield capacity, additional aviation traffic generated by AAM operations may be welcome. Smaller airports have runways and other airside facilities that are typically well-suited for the operations of commuter aircraft. However, depending on the airport layout, typical taxi-in and taxi-out time, existing capacity and delay, and other operational criteria, new dedicated facilities may be considered. For instance, a FATO for VTOL aircraft closer to the terminal facilities can help minimize the turnaround time if the existing layout imposes long taxiing procedures on the runways. At airports served by higher approach speed aircraft, at near- capacity airfields, or where AAM could create delays or other operational issues, new dedicated facilities could be considered. This includes additional FATOs for VTOL aircraft and short runways for STOL aircraft. Some of these facilities, especially for VTOL operations, could be completely separated from the main AOA and passenger terminal infrastructure. When considering a vertiport outside the main airport AOA, the stakeholders should consider which of the two following criteria should be prioritized: • Facilitating vertiport accessibility and interconnection with ground transportation modes as a multimodal platform. This can make the case for implementing a “landside” vertiport to enhance the interconnectivity with other transportation modes like the facilities used at Los Angeles International Airport with a heliport on the rooftop of parking garage P-4 (see Figure 15). • Facilitating connections with other commercial flights. This criterion promotes the accom- modation of AAM flights within the main airport’s AOA, and the processing of AAM passengers through a designated sterile area following the same screening rules as elsewhere at the airport. The main advantage of such an arrangement is that it can expedite connections and bag trans- fers. This implies that both the passengers and bags are screened either at the departure facility or after their arrival at the airport. When the preferred alternative is selected, the AAM working group needs to prepare an implementation plan that sets up priorities and defines a timeline. Key milestones or develop- ment projects can be triggered by the level of demand instead of years if the future demand is uncertain. Associated costs should be estimated to inform further decision making and potential inclusion in the airport’s capital improvement program. Aviation Safety Considerations Airport operators, flight operators, and other stakeholders of airport operations are responsible for performing a safety risk assessment when introducing changes to their operations as part of their safety management system. New aviation activities involving emerging technologies

72 Urban Air Mobility: An Airport Perspective and stakeholders unfamiliar with the airport may warrant a safety assessment. An airport safety review of electric aircraft and hydrogen technologies is provided in Appendix E of ACRP Research Report 236: Preparing Your Airport for Electric Aircraft and Hydrogen Technologies. More information on safety management systems and safety risk assessment for airports is available in AC 150/5200-37A: Introduction to Safety Management System (SMS) for Airport Operators, ACRP Report 1: Safety Management Systems for Airports, Order 5200.11: FAA Airports (ARP) Safety Management System, and Order 8000.369C: Safety Management System (FAA 2007; Ludwig et al. 2007; FAA 2010; FAA 2020a). 6.4 Vertiports According to the FAA, a vertiport is an identifiable ground or elevated area, including any buildings or facilities thereon, used for the take off and landing of tiltrotor aircraft and rotorcraft. Currently, there are approximately 5,900 heliports in the United States, with 5,842 private use and 58 public use facilities. Although heliports are designed specifically for helicopter take off and landings, they can accommodate or can be adapted to serve the next generations of eVTOLs. Table 14 shows the annual operations of four of the busiest heliports in the United States, and Table 15 shows the annual aviation activity at selected downtown heliports per the latest FAA Airport Master Record database. The emergence of UAM may significantly increase the number of operations at selected heliports and will likely create demand for additional vertiport facilities. In general, UAM will most likely consist of on-demand flights (public charters). The industry has been using the following different terms for describing three levels of equipment and sizes of facilities regarding vertiports: • Vertipad or Vertistation. This facility is the smallest and simplest of the three. It typically comprises one take off/landing site with one or two parking spots for the aircraft. It would serve as a point of connection in typical suburban areas to the other vertiport networks. MRO facilities and repair services would not occur because of the small footprint of the pad/station. Heliport Name 3-Letter FAA Code Location Estimated Annual Operations Fiscal Year Downtown Manhattan JRB New York, NY 31,510 2017-2018 East 34th Street 6N5 New York, NY 18,282 2016-2017 West 30th Street JRA New York, NY 14,510 2016-2017 Waikoloa HI07 Waikoloa Village, HI 6,000 2015-2016 Source: FAA 2022b. Heliport Name 3-Letter FAA Code Location Estimated Annual VTOL Operations Fiscal Year Haverstraw H43 New York, NY 2,300 2018-2019 Dallas CBD Vertiport 49T Dallas, TX 730 2017-2018 South Hampton 87N New York, NY 400 2015-2016 Source: FAA 2022b. Table 14. Aviation activity at the four busiest United States heliports. Table 15. Annual VTOL operations at selected downtown heliports.

Planning Strategies for Integrating Urban Air Mobility into Airports 73 Also, passenger accommodation, such as terminals would not exist and/or be staffed, similar to existing helipads and helistations. • Vertiport or Vertibase. This facility, unlike the vertipad/vertistation, would be located in the center or at key points in urban areas. The vertiport would have two to three FATO/TLOF and some parking positions to accommodate the UAM aircraft traffic. This facility would also staff a basic maintenance crew for the aircraft. Charging stations would be needed and would most likely be limited to quick charging and battery-swapping method. Passenger waiting areas (terminals) and some security screening would be needed. • Vertihub. This facility would be the largest of all three. These facilities would possess enough space for multiple aircraft parking locations, including overnight parking. A fully functional MRO facility would be present to allow aircraft to undergo intensive maintenance. Many vertihubs may provide a broad range of services and amenities to passengers, including food and beverage options. Table 16 presents the typical features and characteristics of the vertihub, vertiport, and vertipad. Passenger Facilities and Services Depending on the size and complexity of the vertiport, various functions need to be available to accommodate passenger needs. They include the following: • Ticketing and Customer Service. Automation and self-service are at the core of the vertiport ticketing. Most passengers would purchase their ticket online and through apps. Some counters and kiosks would allow passengers to purchase tickets on-site. Customer service personnel, potentially at larger facilities, may be offered, including trip planners helping passengers booking door-to-door mobility tickets or providing concierge premium services. Vertihubs Vertiport/baseHeliport/helibase Vertipad/station Helipad/helistation Minimum Footprint 400 ft. x 200 ft. 250 ft. x 100 ft. 100 ft. x 60 ft. FATO/TLOF 2+ 1-2 1 Typical VTOL Stands 10+ 2-10 1-2 MRO Capabilities MRO capabilities Limited capabilities Not available on-site Capital Expenditure $6–7 million $500,000–800,000 $200,000–400,000 Operating Expenditure $15–17 million $3–5 million $600,000–900,000 Images Source: NASA 2021c. Data Source: McKinsey & Company 2020. Table 16. Types of vertiport facilities and services.

74 Urban Air Mobility: An Airport Perspective • Concessions. Food and beverage options could be provided in the terminals for passengers awaiting their flights. These services boost passenger experiences and provide revenue to the facility. • Holdrooms/Security. Holdrooms and the boarding areas might feature some level of access control, especially at vertiport and vertihubs. Security measures depend on the security risk assessment and TSA determination of the security requirements for UAM and vertiport facilities. • Access to the Aircraft. At most vertiport facilities, passengers will likely walk from the terminal to the aircraft via protected passenger walkways. Some facilities may feature canopies to protect passengers from adverse weather conditions. • Baggage Services. Although most UAM trips would be short, some passengers may carry luggage, especially those to and from airports. However, options for carrying large bags will be limited because of payload and cabin volume limits. UAM service providers may offer “door-to-door” baggage services for passengers carrying larger or multiple bags. Cargo Facilities Vertiport facilities for cargo operations range from droneports for sUAS delivering foods and goods to more complex cargo vertihubs served by larger cargo VTOL UAS operating warehouses and shipment centers. Collaboration among industries to standardize container specifications could allow for interoperable semi- or fully automated cargo handling. Applications for sUAS droneports in urban, suburban, and rural areas include delivering time-sensitive medical and pharmaceutical products at hospitals and other healthcare facilities, last-mile delivery of mail and parcels to local boxes, and shipping fulfillment for e-commerce. In cases where larger cargo needs to be stored at vertiports, designated storage facilities or warehouses would be required with easy access to both airside and landside, and the type and size would be entirely based on the anticipated volume and type of cargo, similarly to existing air and ground freight facilities. Medical Service Provisions The medical use of vertiport would include the transportation of patients, medical personnel, and equipment. Currently, heliports that serve medical purposes are mostly located at or near hospitals and medical facilities. One example is Vertiport Chicago, which serves the medical community. The vertiport has made provisions to ensure easy access for emergency medical services and the efficient transportation of patients and other medical supplies. The vertiport offers dedicated access for ambulances from the landside to the ramp, which is triggered by the ambulance sirens, enabling quick access without delay. The facility also has a fueling station for conventional helicopters. Vertiports providing accommodations for aerial medical services can be grouped into the following three types: • Conventional public-use vertiports: These are conventional vertiports that serve all uses including passenger transfers by emergency medical services for medevac and patients. • Emergency medical service-ready vertiports: These are vertiports with provisions for emergency medical services. These vertiports can also accommodate other use cases (e.g., Vertiport Chicago). • Hospital vertiports: These are street-level or elevated vertiports solely dedicated to emergency medical service operations in and out of hospitals, located on-site and often on the rooftop of medical facilities. While most of these facilities do not provide traditional fueling services, they might be equipped with electric chargers in the future if the emergency medical service community transitions to eVTOLs.

Planning Strategies for Integrating Urban Air Mobility into Airports 75 Maintenance and Repair Operation VTOL aircraft need regular maintenance and occasional repairs. Selected vertiport facilities, especially vertihubs, would provide maintenance and repair services. Full maintenance services, airframe and powerplant, and avionics may be provided at some locations. Alternatively, VTOL operators can employ mobile maintenance and repair shops on an as-needed basis to maintain and repair aircraft when necessary. An example of a vertiport ecosystem with large vertihubs is São Paulo, Brazil. This large metropolis has a thriving community of helicopter operators that is served by several vertihubs in and around the city—such as HBR, Helicidade, and Helipark—all offering MRO services. 6.5 General Aviation Facilities Approximately 5,000 public-use airports, heliports, and seaplane bases are located in the United States. Approximately 3,300 of these public-use facilities are included in the NPIAS. Of these 3,300 NPIAS facilities, over 2,500 are general aviation facilities—defined as public-use airports that do not have scheduled service or have scheduled service with fewer than 2,500 passenger boardings each year [49 CFR §47102(8)]. These facilities primarily support aeromedical flights, aerial firefighting, law enforcement, disaster relief, private recreational and business flights, and provide air taxi services to communities. About 200,000 active general aviation aircraft in the United States are responsible for approximately three-quarters of all aviation activity. Accommodating AAM at general aviation airports will vary depending on the current ownership of the airport, lease agreements, and feasibility of implementing AAM operations. At general aviation airports already accommodating similar operations (e.g., air taxi, cargo, medevac), AAM operations may be easily integrated into the existing infrastructure without creating new facilities. Indeed, runways at these airports can be considered STOL runways and perfectly meet AAM operation requirements. Dedicated AAM facilities can also be considered at near-capacity airports or where their operations make sense. Discussions on dedicated facilities should address several issues, including the status of such a facility from the safety and security standpoints, flight procedures and air traffic services, passenger accommodation, operations and maintenance of the facility, charging infrastructure, accessibility by different flight operators, land use, compliance to grant assurances, as well as cost-benefit and funding considerations. Cargo Facilities The emergence of AAM, especially with sUAS vehicles and drones, will provide cargo operators the opportunity to perform last-mile/short-haul delivery services to rural and remote commu- nities, where ground access could be difficult. To facilitate cargo operations, general aviation airports could decide to provide a specific cargo platform, with easy access to the airside and landside. Depending on the type of cargo operations, semi- or fully automated cargo warehouses may be implemented. Medical Service Provisions Similar to cargo services, isolated communities will benefit from new AAM vehicles to transport patients, medical personnel, and equipment, especially when roadway access is difficult and critical for emergency medical services. General aviation airports may decide to provide dedicated access for ambulances from the landside to the ramp to ensure and facilitate emergency medical services operations.

76 Urban Air Mobility: An Airport Perspective From General Aviation to Commercial Service Airports AAM aims to provide point-to-point connections as close as possible to the doorstep of the initial departure point and the final destination of the passenger. To achieve this goal, AAM providers may prioritize underutilized smaller aviation facilities rather than only operating from larger commercial service airports with wide catchment areas. Offering AAM flights closer to the demand will shorten trips and allow AAM providers to better serve local markets, including dense urban areas, suburban communities, smaller cities, and rural and remote areas. The development of AAM operations at general aviation facilities will increase the use of these local aviation assets. Passenger traffic might rapidly exceed 2,500 annual enplanements. AAM may move from general aviation to non-primary or primary non-hub commercial service air- ports. General aviation airports with AAM services will have smaller catchment areas compared with larger commercial service airports but can provide “community service” airport connec- tions to larger commercial service airports. 6.6 Commercial Service Airports According to Title 49 CFR §47102, a commercial service airport is a publicly owned airport with at least 2,500 annual enplanements and is receiving scheduled air carrier service. NPIAS for the period 2021–2025 categorized commercial service airports as follows: • Large hub: airports that each account for 1 percent or more of annual U.S. commercial enplane- ments. NPIAS identified 30 large hub airports in the United States. • Medium hub: airports that each account for 0.25 to 1 percent of annual U.S. commercial enplanements. NPIAS identified 31 medium hub airports in the United States. • Small hub: airports that each account for 0.05 to 0.25 percent of annual U.S. commercial enplanements. NPIAS identified 69 small hub airports in the United States. • Non-hub primary: airports that each account for less than 0.05 percent of annual U.S. commer- cial enplanements. NPIAS identified 266 non-hub primary airports in the United States. The emergence of AAM will affect commercial service airport operations, and its successful integration into the airport ecosystem needs to be carefully balanced with the rest of the airport operations. The following three types of services will be provided by or be integrated with AAM: • On-demand air service: Air taxi services might transport a small number of passengers (2–6) on short distances with UAM (intra- or inter-city) and between communities (RAM). • Scheduled air service: Scheduled air service might occur with RAM to provide regular flights between communities and to larger hub airports with 2- to 19-seaters at first, and perhaps larger regional electric aircraft later on. • Mobility-as-a-Service: UAM, RAM, and MaaS providers may offer travel options from door- to-door to the passengers, integrating the first- and last-mile services. AAM flights would likely be available through smartphone and online applications similar to the way TNCs operate. Passenger Facilities and Services As described in ACRP Research Report 236: Preparing Your Airport for Electric Aircraft and Hydrogen Technologies, although AAM aircraft shape or size will not fundamentally affect existing infrastructure, passenger terminals could experience consequences similar to those experienced after the airline deregulation in the 1970s: more aircraft flying resulted in an increase of passenger loads, which raised the issue of inadequate or inflexible passenger terminal facilities. Urban and regional flight demand from AAM aircraft may require airports to adapt their passenger terminal facilities to accommodate demand. Remote ramps or “non-contact” gates,

Planning Strategies for Integrating Urban Air Mobility into Airports 77 which are typical at small airports, could be implemented for AAM traffic. Such a process involves passengers walking from the holding room to the aircraft. If, for passenger experience reasons, large hub airports have abandoned this process, they may decide to adopt it for AAM demand. Canopies or ground-level boarding stairs could be installed to protect passengers from weather conditions. To optimize aircraft operations and passenger movements, airports may decide to build a new terminal or dedicate an existing terminal facility to AAM. These dedicated facilities could be designed to meet AAM’s ground and terminal operating requirements and provide flexibility within the terminal for AAM operators for their operational needs. These issues are not different than the questions that arose from the development of regional and commuter aviation in the 1980s and 1990s. They are discussed extensively in ACRP Research Report 236: Preparing Your Airport for Electric Aircraft and Hydrogen Technologies. For instance, Concourse F at Philadelphia International Airport was designed specifically for regional and commuter aircraft. At Boston Logan International Airport and St. Louis Lambert International Airport, Cape Air’s regional flights operated with small commuter aircraft (e.g., Cessna 402 and Tecnam P2012) and are accommodated with smaller nose-in/nose-out stands along the main terminal buildings. At Logan International Airport, these stands adopt the use of a Multiple Aircraft Ramp System configuration because they are shared with JetBlue and used for the remote overnight parking of larger jet aircraft (Figure 12). At St. Louis Lambert Inter- national Airport, Cape Air stands are located along Terminal 1 (Figure 13). At smaller airports (e.g., non-primary and primary non-hub airports) such as King County International Airport (Figure 14), AAM passenger terminal facilities and aprons should have the following features: • Typical facilities and amenities inside the terminal (e.g., ticketing, holdrooms). Concessions and retail options would probably be limited compared to busier commercial service airports. As discussed earlier in the report, security screening depends on the type of operation, level of traffic, and TSA determination. Source: Google Earth. Figure 12. Cape Air stands at Boston Logan International Airport.

78 Urban Air Mobility: An Airport Perspective Source: Google Earth. Source: Google Earth. Figure 13. Cape Air stands at St. Louis Lambert International Airport. Figure 14. Passenger terminal facility at King County International Airport.

Planning Strategies for Integrating Urban Air Mobility into Airports 79 • Walkways painted on the ground for passenger boarding. • Staging areas for ground support equipment. • Aircraft parking at gates located in the immediate vicinity of the terminal building. • A separate apron from the other aviation activities (e.g., private/recreational aviation, flight schools), dedicated to air carriers’ activities. Cargo Facilities AAM cargo operations at commercial service airports may include (1) “feeder” operations with freight being carried by small electric aircraft from smaller airports to larger cargo hubs, (2) parcel and freight delivery from larger cargo hubs to smaller airports, and (3) parcel and small cargo delivery from warehouses at the airport to neighborhood delivery centers and residential areas. Feeder operations as delivery to local airports are performed by commuter or regional aircraft converted for cargo operations. With AAM, these aircraft could be replaced by electric aerial vehicles that could ultimately be unmanned. For instance, DHL Express and UPS have expressed their interest in acquiring Eviation Alice and BETA Technologies ALIA, respectively. Cargo deliveries from warehouses to local shipment centers or residential areas could primarily be performed by sUAS delivering parcels and other small payloads. UPS Flight Forward is certified under Part 135 by the FAA for performing commercial UAS flights BVLOS. Heavier payloads may be delivered by air or by larger UAS. In Germany, Volocopter and DB Schenker have performed static proof of concepts for logistics operations with the VoloDrone, which can carry 440 pounds (200 kg) over a distance of up to 25 miles (40 km). Today, air traffic control authorization requirements for drone operations near airports are supported by the LAANC. Through the LAANC, remote pilots can apply to receive a near real- time authorization for operations under 400 ft in controlled airspace around airports. The UTM will provide further capabilities. The most recent vision of the FAA and the industry on UTM is described in the 2020 UTM Concept of Operations v2.0 (FAA 2020c). Vertiport Facilities and STOL Runways at Airports Airports might consider attracting AAM providers by enhancing accessibility to the commu- nities they serve, as well as attracting new, short-haul air services. To preserve capacity and increase efficiency, some airports may elect to develop new, separate facilities for accommodating these operations. Vertiports can be located outside the main AOA, such as the former heliport at Los Angeles International Airport on the rooftop of parking garage P-4, depicted in Figure 15. Many airports also have VTOL facilities within their main AOA as vertipads on taxiways or ramps—the VTOLs using aircraft stands for the quick turnaround (e.g., John F. Kennedy International Airport), or separate vertiport facilities within the same AOA (e.g., Paris-Charles de Gaulle International Airport), depicted in Figure 16. Dedicated STOL runways can be developed to accommodate the slower, more wake turbulence- sensitive traffic consisting of turboprops and other smaller regional aircraft to optimize separation and facilitate aircraft speed management in the approach. Shorter runways were developed for this purpose in the 1980s and 1990s to accommodate commuter and regional flights operated with turboprops and small regional jets at large hub airports such as John F. Kennedy International Airport (Figure 17) and Philadelphia Inter- national Airport (Figure 18). The short runway 14-32 at Kennedy was closed in the 1990s, and its footprint is now part of Taxiway E. The 5,000-foot-long runway 8-26 at Philadelphia is still in operation as a one-direction runway.

80 Urban Air Mobility: An Airport Perspective Source: Google Earth. Source: Google Earth, AIP LFPG. Figure 15. Former heliport at Los Angeles International Airport in 2008. Figure 16. Heliport facilities at Charles de Gaulle Airport in 2021.

Planning Strategies for Integrating Urban Air Mobility into Airports 81 Source: Google Earth. Source: Google Earth. Figure 17. Runway 14-32 at John F. Kennedy International Airport in 1994. Figure 18. Runway 8-26 at Philadelphia International Airport in 2021.

82 Urban Air Mobility: An Airport Perspective When a dedicated AAM facility is provided, especially when the facility is a separate verti- port or STOLport outside the main AOA, the airspace and airside aspects should be carefully considered to provide adequate planning provisions and operational coordination for preserving safety and capacity, including: runway-to-runway or FATO separation distances, air traffic control, and flight procedures; aircraft rescue and firefighting; transportation security require- ments; and accessibility for people with reduced mobility. The pros and cons of accommodating AAM services on dedicated facilities are discussed later in this document. 6.7 Utilities and Support Infrastructure Electric and Hybrid Propulsion System Requirements Different solutions and configurations are being explored to power new aerial vehicles. The two main alternatives for storing and delivering power to electric propulsion systems are (1) electro- chemical batteries that deliver electricity to the engine, and (2) fuel cells that convert hydrogen (and air) into electricity (and water). Hybrid-electric propulsion systems combine one or more of these alternatives with a conventional (thermal) engine such as a piston engine, a turboprop, or a jet engine. The technical solutions for resupplying aerial vehicles powered by electricity or hydrogen infrastructure are summarized in Table 17. ACRP Research Report 236: Preparing Your Airport for Electric Aircraft and Hydrogen Technologies explores electric aircraft and hydrogen tech- nology compatibility issues and how to address them through planning and design in the con- text of the “electrification of everything” and the emergence of the hydrogen economy as other activities and functions of the airport, such as ground vehicles and building heating systems, are transitioning to electricity or hydrogen as well. Utility Upgrades Utility upgrades may be warranted at airports where the peak demand significantly exceeds the capabilities of the existing infrastructure. Table 18 summarizes the estimated cost for utility upgrades for airports and vertiports based on the power needed, according to the National Institute of Aerospace and NASA in the eVTOL Electrical Infrastructure Study for UAM Aircraft (Black & Veatch n.d.). Additionally, on-site power generation infrastructure can be considered as an alternative for meeting the electric aircraft demand and increasing resilience. This solution provides more Ramp Integration Batteries Fuel Cells Fixed Airport Units Electric Chargers Hydrant System Mobile Airport Units Superchargers on Truck/Trailer Tanker (Truck) Swapping Energy Containers Battery Swap Container Swap Estimated Budget Pricing Description $100,000 Service supply extension; up to 1 MW (up to three chargers) $264,000–$1,300,000 per mile New conductor/reconductor; over 5 MW (up to eight chargers) $3,000,000–$11,000,000 New transformer bank; over 10 MW (over 15 chargers) $40,000,000–$80,000,000 New substation bank; over 20 MW (over 30 chargers) Table 17. Recharge and refueling technologies for electric propulsion systems. Table 18. Budget estimate pricing for utility upgrades.

Planning Strategies for Integrating Urban Air Mobility into Airports 83 autonomy from the grid for airports. Costs associated with installing these systems can vary widely—from $250,000 for small systems up to $100 million for larger multimode systems. Backup Power Supply As electricity becomes an aviation “fuel” or energy vector, the need to preserve operational resiliency and mitigate the effect of power outages on aviation operations will increase. Microgrids can help aviation facilities achieve resilience by backing up or supplying part or all of the power demand because they are composed of more than one power-generating source, including batteries (power packs), solar panels, diesel generators, hydrogen fuel-cell generators, and natural gas generators. To determine the best backup power for airports, numerous factors need to be considered. ACRP Research Report 236: Preparing Your Airport for Electric Aircraft and Hydrogen Technologies and ACRP Synthesis 91: Microgrids and Their Application for Airports and Public Transit discuss these factors and the costs of acquiring and operating such systems (Heard and Mannarino 2018). Table 19 shows rough order of magnitude for the cost of each backup power option. The table excludes battery storage because of its different means of operation. It requires no fuel, and battery configurations significantly vary, thus a cost-per-kilowatt cannot be calculated. The paragraphs below detail these costs. Operating Cost. The operating cost for backup power comprises the maintenance and fuel costs. Fuel Cost. The estimated cost for fuel is per kilowatt-hour (kWh) and is calculated by multi- plying current regional fuel costs by the fuel consumption per hour of the associated technology. Table 20 summarizes the estimated fuel costs. Maintenance Cost. Other than the price of fuel, the periodic repair and maintenance of the unit add to the operating cost. The regularity of maintenance primarily depends on the frequency of unit usage. Fewer operation hours, primarily for emergencies, translate to less frequent unit maintenance. The maintenance costs used in this analysis were sourced from the National Renewable Energy Laboratory and are applied equally to all backup power options. The operating costs included in this analysis, in Table 20, do not explicitly account for permitting. Fuel Type Diesel Natural Gas Hydrogen Generator $580 $725 $1,500 On-site Fuel Storage $2 N/A; not stored on site. $4 Installation $150 $160 $333 Fuel Type Diesel Natural Gas Hydrogen Fuel Cost $3.40/gallon $1.17/therm $9.00/kilogram Fuel Cost $0.24 kWh $0.12 kWh $0.20 kWh 1-Year Maintenance Costs (Per MW) $35,000 $35,000 $36,750 Table 19. Estimated capital costs per kilowatt of power. Table 20. Estimated fuel costs and estimated yearly maintenance costs.

84 Urban Air Mobility: An Airport Perspective Chargers Most, if not all current heliports have no charging abilities. The electrification of VTOLs, to be known as vertiports, would warrant the need for electric aircraft charging facilities; thus, the option for on-site chargers should be explored. The number of chargers per station would vary based on the availability of square footage, the capacity of the electric grid infrastructure, charger power, the number of AAM electric-powered aircraft operations, and the type of AAM vehicle that will operate on the site. Table 21 shows the estimated charger prices, excluding utility costs. Hydrogen Supply Chain for Aviation Hydrogen is a prospective “fuel” or energy vector for electric aircraft used for AAM, especially for larger regional aircraft. It has, however, been introduced to other smaller aircraft capable of AAM. Hydrogen is produced from energy sources such as wind, solar, water, and coal, among others. The cost of hydrogen production, not taking into account the capital cost (cost of purchasing and maintaining fixed assets such as buildings where the hydrogen will be produced and associated equipment) ranges from $1.4/kg to $23.5/kg depending on the process used. High-pressure hydrogen, which is primarily the type of hydrogen used for fueling, requires a highly developed storage system because of its hazardous nature (e.g., flammability, low viscosity, low ignition energy). The utilization of hydrogen would be appropriate for aircraft operating from STOLports and from conventional commercial service and general aviation airports, where a hydrogen infrastructure could be implemented based on current technologies and capabilities. Urban vertiports, however, would face challenges in accommodating such infrastructure and being resupplied, especially with elevated vertiports located on the rooftop of high-rises. ACRP Research Report 236: Preparing Your Airport for Electric Aircraft and Hydrogen Tech- nologies discusses several aspects of hydrogen for aviation and provides a review of the safety and standardization challenges pertaining to the accommodation of hydrogen technologies at aviation facilities. 6.8 Advanced Air Mobility for Airport Master Planning The long-term development of an airport is driven by its master plan. The master planning process establishes capital development initiatives for an airport and a long-term plan for incre- mental and flexible development. Master plan studies include environmental considerations, Estimated Budget Pricing Description $883,000 Single charger station incorporated into an existing building landing pad on a five- story building. Pricing does not include utility costs. $1,876,000 Three charger stations are incorporated onto an existing roof on a five-level parking garage. Pricing does not include utility costs. $2,630,000 Three charger stations installed into a ground-based station. Pricing does not include utility costs. $10,200,000 Ten charger stations were installed into a ground-based station. Pricing does not include utility costs. Source: Black & Veatch. Table 21. Budget estimate pricing for chargers.

Planning Strategies for Integrating Urban Air Mobility into Airports 85 facility requirements, airport layout plans, facilities implementation plans, and financial feasibility analysis, among other components. AC 150/5070-6B: Airport Master Plans provides guidance for preparing a master plan (FAA 2005b). According to the AC, the master plan provides the framework needed to guide future airport development that will cost-effectively satisfy aviation demand, while considering potential environmental and socioeconomic impacts. The master plan is a comprehensive study of the airport that describes short-, medium-, and long-term plans for airport development. With the emergence of AAM, master plans will need to consider new airside and airspace users in the following ways: • Pre-planning: During the pre-planning process, the planning needs should be identified based on future potential shortcomings. Planning could be triggered by a capacity reached, the introduction of new aircraft types, or the emergence of a critical environmental problem. Airport stakeholders can also identify future needs and inform the airport. Typically, airlines can announce their intentions to open new routes with a new aircraft type. The type of study should be determined to answer the needs (e.g., a full airport master plan or a simple technical report). – AAM: The pre-planning process should consider the introduction of new aircraft types, which could trigger the need for a specific planning study. The scope of work, if applicable, should indicate that AAM should be considered throughout the master planning process. • Public Involvement: The creation of a public involvement program should be done in the earliest stage of the master plan development. Public involvement is intended to share infor- mation about the planning study and encourage collaboration among the airport sponsor, users and tenants, resource agencies, elected and appointed public officials, residents, travelers, and the general public. It is important to involve stakeholders with an early opportunity before any major decisions are made to consider their comments and educate them about the future potential airport development. – AAM: UAM and RAM will be mainly provided by electric and hybrid-electric aircraft that are significantly quieter and less emitting than conventional aircraft. Consequently, any substitution of existing traffic or moderate increase should not adversely affect noise exposure, air quality, and the carbon footprint. However, the introduction of regular commercial services at smaller general aviation facilities, the creation of new STOL- and vertiports, and the development of UAM routes or corridors might call for public involve- ment and stakeholder outreach programs. • Existing Conditions: Master plans require an inventory of existing conditions for both physical attributes and operational and performance characteristics of the airport and related facilities and infrastructure. The inventory includes the airside, passenger terminal, and land- side facilities. The regional setting of an airport and the land use patterns around should be examined, as well as an environmental overview. – AAM: The inventory of existing conditions includes documenting the utility infrastructure. It also includes identifying commercial service and general aviation facilities and planned improvements, which may include existing plans for electricity and hydrogen storage and distribution if applicable. Helicopter facilities should also be captured. • Aviation Forecast: Aviation activity forecasting completed during the master planning process informs future facility requirements and the timeline for airport development and improvements. An appropriate forecast methodology must be selected accordingly to the level of effort required by the master plan. This step is crucial in a master plan development and must be submitted to the FAA for review and approval, before being used as a basis for the facility requirements. – AAM: Aircraft fleet mix projections are a component of the master planning process that will also need to consider AAM in the future. Studying the local AAM market and

86 Urban Air Mobility: An Airport Perspective forecasting activity among future aircraft operations will help in planning for their accom- modation. Like regular aircraft, the new types of aerial vehicles under development for AAM should be identified and forecasted individually. Vehicles with a special performance, such as STOL and VTOL aircraft, should be carefully distinguished, as they may have specific facility requirements. Aircraft using new and emerging energy vectors (electricity or hydrogen) should also be identified. New or modified service patterns resulting from the introduction of AAM (e.g., more flights offered with smaller aircraft) should be addressed. Note: The FAA Terminal Area Forecast does not consider new aerial mobility. Guidance on electric aircraft for long-term planning is provided in ACRP Research Report 236: Preparing Your Airport for Electric Aircraft and Hydrogen Technologies. Also, early national trends on AAM may appear in the FAA Aerospace Forecasts. Forecasts on UAS operations are already available. • Facility Requirements: After the approval of aviation forecasts, the next step determines the adequacy of the existing airport facilities to accommodate future demand, and if any additional facilities will be required. These requirements are driven by the circumstances of each airport, which includes capacity shortfalls, enhanced security requirements mandated by the TSA, new or updated design standards, airport sponsors’ and the stakeholders’ strategic vision for the airport, and outdated facilities. – AAM: AAM can trigger specific facility requirements, such as ▪ Dedicated terminal building for urban or regional flights, ▪ Dedicated vertiport/STOLport for AAM operations that is separate from the existing terminal and airside facilities, ▪ Charging infrastructure to supply electric power to the aircraft stand, ▪ Airport electricity infrastructure upgrade to supply this charging infrastructure, and ▪ Hydrogen infrastructure to supply gaseous or liquid hydrogen to the aircraft stand. Airport sponsors should discuss the need for electric and hydrogen charging infrastruc- ture with relevant stakeholders. Note: A spreadsheet is provided in the toolkit provided with ACRP Research Report 236: Preparing Your Airport for Electric Aircraft and Hydrogen Technologies for developing electric aircraft and airport utility facility requirements. • Alternatives Development and Assessment: Based on the facility requirements, the alterna- tive development process: identifies alternative ways to address previously identified facility requirements; evaluates the alternatives, individually and collectively, to gain a thorough understanding of the strengths, weaknesses, and other implications of each; and selects a recommended alternative. – AAM: Alternatives should address the needs of AAM, including charging locations, tie-in options, and hydrogen supply. • Airport Layout Plans: The drawing set of the ALP must include a cover sheet, the ALP depicting existing and future airport facilities, a data sheet, facilities layout plans, terminal area plans, airport airspace drawings, the inner portion of the approach surface for each runway, on-airport land use drawings, off-airport land use drawings, airport property maps, runway departure surface drawings for each runway, utility drawings, and airport access plans. ALPs are also subject to approval by the FAA to receive federal funding. – AAM: Some features of the AAM infrastructure (urban and regional aviation terminal building, microgrid power generators, electric chargers, alternative charging means, and hydrogen storage) may be depicted in the ALP drawing set. • Facilities Implementation Plan: This plan is the framework for how to implement the find- ings and recommendations of the planning effort. It will differ depending on the complexity of a project and vary from an airport to another. Local conditions will significantly influence the schedule, the costs, and any special regulations. – AAM: The implementation of the AAM infrastructure should be considered. Electricity and utility connection providers should be involved in this plan if an upgrade of the power

Planning Strategies for Integrating Urban Air Mobility into Airports 87 supply infrastructure and the connection to the grid is required. Such an approach needs to consider the future of the overall electricity demand of the airport, as well as plans for decentralized power generation, including microgrids. • Financial Feasibility Analysis: During this analysis, the airport sponsor demonstrates how it can fund the projects in the master plan and present the capital improvement program. – AAM: The eligibility of AAM-related projects to available funding mechanisms should be carefully evaluated, as part of the support infrastructure (e.g., utility upgrades, aircraft electric chargers) might be outside the scope of traditional aviation infrastructure grants. See ACRP Research Report 236: Preparing Your Airport for Electric Aircraft and Hydrogen Technologies for a review of existing grant programs and the eligibility of electric aviation- related projects. The investment of OEMs as well as AAM providers and flight operators into the infrastructure may be considered as a potential alternative to access funding. 6.9 Advanced Air Mobility Corridor Planning AAM corridors or routes are similar, in urban and regional planning terms, to transit corridors for ground transportation. Studies for developing or promoting AAM corridors include both market and technical studies. They may be conducted by State DOTs, State aviation commis- sions, MPOs, cities and counties, chambers of commerce, other local governments and institu- tions, or a combination of these. AAM corridor planning study should identify market-based opportunities for providing AAM services within and between cities and communities, create an inventory of relevant aviation and non-aviation assets that could be used for AAM opera- tions (e.g., helipad-ready rooftops that could be turned into vertiports), propose alternatives to facilitate the emergence of such a corridor, and develop a plan for implementing the preferred alternative. These studies should also consider the policy, land use, environmental, and safety implications of such corridors. While these efforts typically consider entire aviation systems rather than individual airports, airport operators and selected stakeholders should be involved with AAM corridor planning projects.