Roadmap to Early Implementation of Passenger Air Mobility: Findings from a Delphi Study
2. Related Work
2.1. Uncertainties and Challenges
2.3. Hazards and Risks
- Technological: including various aspects of technology failures . These can include powertrain, GPS/receiver failure, and problems with the autonomous systems;
- Operational: targeting the aircraft and the traffic management, especially if the integration of the UAM and the existing commercial aerospace ecosystem is not seamless ;
- External environment: weather, collision with birds , tall buildings, and power lines;
- Human-related: inadequate pilot training for maintaining safety margins, loss of situational awareness and errors made by pilots , passenger interference in the systems, and emergency/sickness situations of the passengers;
- Ground infrastructure: lack of vertiport availability (occupied, damaged, closed to traffic) and inadequate ground crew training for maintaining safety margins.
2.4. Use Cases
3.1. Study Setup
3.2. Experts Selection
- Identifying researchers and scholars working in the area of UAM and electric aviation;
- Attending conferences and online webinars, in order to shortlist speakers and panelists. These were often consultants and investors;
- Shortlisting founders of startups including air taxi manufacturers, ATM, or electric powertrain solutions for aircraft;
- Contacting policymakers in the aviation space, for instance from EASA and FAA.
3.3. Survey Structure
- What are the biggest challenges for the implementation of PAX-UAM?
- What opportunities do you see with the implementation of PAX-UAM?
- What are the greatest hazards during the operation of PAX-UAM?
4.1. First Round
4.1.3. Use Cases
- Emergency or medical services: this includes transportation for medical emergencies (air ambulance), delivery of critical supplies, organ transport, and fire brigade services;
- Connection to remote locations: this could improve mobility and access to remote and underserved areas that may otherwise not have good access to surface transportation or regions where passenger volumes do not justify building new roads or train lines;
- Intercity transport: to increase connectivity between city centers and central business districts directly across regions; this could be particularly relevant where two cities are obstructed by mountains or other terrains, which could be overcome by PAX-UAM services without heavy infrastructure;
- Intracity transport: this could provide fast transportation for cities with consistent traffic jams, i.e., where it would take longer than several hours to cover distances within 30 km of range due to traffic. Volocopter for example is working on the use case of transportation services within cities ;
- Fun/adventure: PAX-UAM could provide the experience of flying to people. This use case is also being considered by Ehang in China ;
- Airport shuttle services: airports are usually located outside the city, with access usually impeded by traffic. PAX-UAM could potentially offer services from a hub in the city center to the airport. Urban hotels in the city center could accommodate such services directly from the hotel to the airport;
- Defense applications (It is important to note that while defense applications do not fall under passenger air transportation (the focus of this paper), this has been kept for the remainder of the paper, as (i) it was spontaneously provided by (some of) the experts and (ii) due to the interesting insights provided by the experts on, but not limited to, this application): although this is currently not seen as the most desirable target by many manufacturers, defense application is likely to be one of the initial applications, especially for the e-VTOLs design . The main advantage of this use case is that certification is not required. This use case can include: rescue operations and transportation of essential and specific assets, police surveillance, and reconnaissance;
- High-speed transport for high-income individuals: PAX-UAM service for business persons can offer a cleaner and greener mode of transport for long business trips in comparison to private cars. This use case was also discussed in ;
- Cargo applications (This is also not a typical passenger air mobility use case, but was kept for the purpose of reporting the experts’ viewpoints): this becomes the most affordable method of moving parcels around metro areas;
- Agriculture use: an agricultural tool for spraying pesticides or insecticides over the fields (however also not pertaining to passenger air mobility);
- Replacement of helicopters.
4.1.4. Hazards and Risk Assessment
4.2. Second Round
- Dependent on technology: safety, noise, certification, autonomy, airworthiness, battery density, and unmanned aircraft system management (UTM);
- Dependent on the use case: community acceptance, affordability, political acceptance, intermodality, regulatory, and infrastructure requirements;
- External factors: shortage of pilots, lack of investment, inaccessible talent, sustainability/environmental concerns, and optimism bias.
4.2.1. Complexity of the Use Cases
4.2.2. Benefits of the Use Cases
5.1. Identified Gaps
5.2. Use Cases’ Assessment
5.3. Risk Assessment
- Very-high-risk zone: namely, community backlash. This is also one the greatest challenges in the implementation of PAX-UAM services;
- High risk zone: this includes unexpected technology failures, problems with batteries, errors by pilots, inadequate air traffic management, interference with physical objects in the air, accidents on the ground and in the air, an unprofitable business, and the hazard of turbulent weather conditions;
- Medium risk zone: this includes cyber-hacking, improperly designed infrastructure, and the malicious behavior of passengers.
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
|AAM||Advanced air mobility|
|ATM||Air traffic management|
|EASA||European Union Aviation Safety Agency|
|e–VTOL||Electrical vertical takeoff and landing airplane|
|FAA||Federal Aviation Administration|
|NASA||National Aeronautics and Space Administration|
|UAM||Urban air mobility|
|UTM||Unmanned aircraft system traffic management|
|VTOL||Vertical takeoff and landing|
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Desai, K.; Al Haddad, C.; Antoniou, C. Roadmap to Early Implementation of Passenger Air Mobility: Findings from a Delphi Study. Sustainability 2021, 13, 10612. https://doi.org/10.3390/su131910612
Desai K, Al Haddad C, Antoniou C. Roadmap to Early Implementation of Passenger Air Mobility: Findings from a Delphi Study. Sustainability. 2021; 13(19):10612. https://doi.org/10.3390/su131910612Chicago/Turabian Style
Desai, Kshitija, Christelle Al Haddad, and Constantinos Antoniou. 2021. "Roadmap to Early Implementation of Passenger Air Mobility: Findings from a Delphi Study" Sustainability 13, no. 19: 10612. https://doi.org/10.3390/su131910612