Technology has always come from human nature. Every new product, service or concept is born to resolve human's problems or meet part of people’s needs. Likewise, urban air mobility is regarded as an ultimate solution to city problems. According to the UN Prospects research, 68% of the world’s population is projected to be urban by 2050. High urbanization and population explosion lead to severe city problems. Modern transportation cannot afford such a heavy burden anymore. Noteworthily, however, urban air mobility is carving an alternative path of original transportation.
The definition of Urban Air Mobility
Urban Air Mobility (UAM), defined as “safe and efficient air traffic operations in a metropolitan area for manned and unmanned aircraft systems.” by NASA, is a promising industry with endless possibilities to assist people in moving by air. This kind of new transportation mode envisions solving traffic congestion, which is in sync with drastically growing urbanization and population, and air pollution caused by fuel-powered transportation.
The UAM vehicles are basically provided with VTOL capabilities, which means these aircrafts are deployed to take off, hover and land vertically, to minimize the required area efficiently and eliminate the need of a runway. Most UAM vehicles are powered by electricity and equipped with multiple rotors to mitigate noise and the impact on the environment, realizing the goal to live in harmony with our surroundings.
Figure1: Urban Air Mobility
When it comes to air transportation, people always come up with airplanes as the first moving tool. However, the traditional airplane mode is no longer enough to meet the public’s demand because of its limitations on huge size, clumsiness and takeoff and landing methods, which are not friendly to cities. People need another way for their movement in cities by air. Plus, the social problems including traffic congestion and high mortality of car accidents and the advanced technology spur people’s interests to develop the urban air mobility.
Compared to traditional airplanes, UAM vehicles are more likely to show up in the cities by virtue of their appropriateness. The appropriate flight range enables UAM vehicles to take intercity and intracity flight and at the same time the vehicles won’t take up other transportation tools’ space due to the particular flight elevation. What’s more, the environmental sustainability of UAM significantly surpasses traditional airplanes owing to its reliance on electricity.
Table1: The comparison of traditional airplane and UAM
The characteristics of Urban Air Mobility.
Faster and More Efficient
Today’s ground transportation is quite complicated due to a blend of different transportation systems including private transport (e.g. automobile, motorcycle and cycle) and public transport (e.g. bus, trams and rapid transit). The complexity of transportation supports the cities' productivity and economic activities. Nevertheless, the robustness of complicated transportation networks is remarkably dependent on the efficiency of transportation systems. If the complexity, population and urbanization are increasing without efficiency, it will ultimately lead to a chaotic and deficient transportation environment. By contrast, UAM could ease such tension with its high-moving and agility, which demonstrates how it improves the efficiency of transportation.
How important is safety to air transportation? Based on ICAO’s accident statistics, the rate of air accidents is in fact quite low, said to be 3.02 per million departures in 2019. Moreover, the 239 deaths of air accidents are far below 1.35 million people killed on roadways. The extreme comparison reveals what is behind ── safety first. Once an airplane has crashed, it will cause uncountable losses such as passengers’ lives, airplane costs, public trust and compensation.
As one of air transportation tools, UAM vehicles also follow the tacit standards of safety to prevent tragedy. UAM vehicles, thus, are typically outfitted with numerous safety features (e.g. crash force reduction and emergency backup system) to elevate the survival rate and avoid hazards.
According to IEA’s findings, transportation accounted for 24% of direct CO2 emissions from fuel combustion and the percentage was continually spiking in recent years. If people are exposed to excess CO2, it will cause a series of illnesses. Meanwhile, CO2 will provoke global warming by absorbing long-wavelength radiation. Although the awareness of global warming and green lifestyle gradually burgeon, the rate of warming still far surpasses human’s efforts in environmental protection.
Noise pollution is kind of a harmful factor to our surroundings as well. The noise regulations are varied by country. But, in general, sounds above 85 dB are harmful. The sounds of ground transportation are between 80 and 95 dB while the airplanes’ sounds are up to 120 db. Furthermore, the reason why helicopters need to fly at altitudes no less than 1,000 feets is because of the acceptable noise criterion of 65db.
Fortunately, electrically-generated UAM vehicles are eco-friendly with zero emissions and relatively low volume. What’s more, the vehicles can deliver a better performance with high agility and manoeuvrability than current ground and air transportation tools that rely on fossil fuels. (Table1 & Table2)
Key components of Urban Air Mobility
Urban air mobility is regarded as a new mode to transport people and cargo on point-to-point routes. UAM vehicles, thereby, are required to possess some critical characteristics to support their flight within urban areas. As aforementioned, VTOL capabilities are no doubt an essential characteristic to differentiate UAM vehicles from traditional airplanes and identify why they are more suitable for cities. Meanwhile, ideal vehicles also need to be compact and manoeuvrable to adapt to changing surroundings, allowing them to fly within crowded cities.
Besides, UAM is endowed with a mission to address traffic problems. Safety is absolutely the top priority that designers and manufacturers should ensure. Fundamentally, safety features (e.g. crashworthiness, power redundancy with distributed electric propulsion and emergency landing system) are a must for UAM vehicles to automatically mitigate the risk of accident and increase the survival rate. But on the other hand, it is suggested to equip UAM vehicles with escape devices (e.g. built-in parachute and emergency brochures) for passengers in case of emergency.
Urban air mobility is a technology-intensive industry because it stresses on efficient performance. A sophisticated vehicle actually consists of abundant technology knowledge, including aerial vehicle system architecture, hardware, software and air and ground operations. Interestingly, nowadays UAM market players are still in an ambiguous position due to the lack of a standard or dominant design in this market.
Besides, certification and intellectual property rights are a sensitive issue for UAM as well. As a brand new industry, the innovation such as new technologies and design needs to be protected since it is a precious asset for companies and needs to be verified by relevant institutions to ensure the quality.
Figure3: Systems Operations
Infrastructure (such as skyports, skyhubs or skystops) is an indispensable element for UAM operations in the cities, setting up bases to perform the procedure of vehicles’ flights. Without a holistic system of physical infrastructure, UAM vehicles would be just some fancy products that surprise the public but fail to meet what people need and ameliorate the social problems.
To establish a series of accessible infrastructure will be a tough mission since it requires UAM to be closely in line with different parties including the country, local government, community and residents and private sectors. For instance, building an infrastructure is a quite capital-intensive activity. The common resource of capital is composed of public and private investment, which are complementary to each other. Hence, it is hard to define the adequate percentage of public and private capital investment respectively to achieve an appropriate equilibrium in boosting UAM development.
In addition to capital, the design and construction of the infrastructure are the point that UAM has to concentrate on as well. Whether infrastructure can meet the community’s needs? How to optimize the placement of infrastructure to be adaptable to the original urban landscape? Will it contribute to annoying noise or harmful impact on the environment? There are plenty of hurdles to overcome. In a nutshell, UAM has to develop a network of collaboration with all parties involved.
Comparison of different transportation tools.
As a novel term of transportation, UAM vehicles are usually described as cars or helicopters. Although they are similar in some ways, the description of UAM is still not precise. In fact, UAM vehicles might be greener and more customised for cities than cars and helicopters in some ways.
By contrast, UAM vehicles are in a favorable position in speed and agility. Obviously, the vehicles are faster than cars, saving passengers a lot of time when taking transportation tools and in turn enhancing the efficiency of the whole transportation network. Furthermore, UAM vehicles are more harmless to our surroundings by drowning noise and achieving zero emissions.
Compared with helicopters, UAM vehicles enjoy advantages in cost, size and efficiency. Even though the vehicles are as expensive as helicopters in the short term, they will ramp up the production and in turn cut down the cost in the long run. Likewise, UAM vehicles are also more friendly to our surroundings than helicopters.
Table2: The comparison of UAM vehicles, cars and helicopters
The other possible UAM scenarios in the future
Disaster relief and Emergency
According to EM-DAT’s survey, tens of millions of people were affected by natural disasters every year for the past five years while tens of thousands of people were wounded and died within the same period. Of all types of natural disasters, floods, extreme weather and earthquakes are listed as the most common natural disasters. When these disasters gripped, the authorities usually relied on traditional transportation tools like cars (e.g. ambulance), ships and helicopters to launch relief operations. Nevertheless, these transportation tools lack efficiency and pose failure risks under circumstances.
UAM vehicles possess the nature of high manoeuvrability and fast-moving, which allows them to shuttle agilely within a particular area to a certain extent. Unlike automobiles, traffic congestion and topography do not cause much a concern to UAM vehicles. The vehicles are speedy compared to ships, but at the same time not as risky as helicopters. In sum, plenty of existing factors won’t jeopardise the relief operations of UAM vehicles.
Figure5: Disaster relief
Logistic and Distribution
In 2019, the global logistics industry market was worth over US$ 4.9 trillion. IMARC Group projected that the market size will reach US$ 6.5 trillion by 2025 while its compound annual growth rate (CARG) will hit 4.7% during 2020-2025. With the prosperity of the E-commerce industry, the logistics market is deeply driven and demonstrates a huge potential.
It might be a good news for logistics providers to enjoy the growth of the market. Yet, accelerating market value doesn’t mean the existing player could afford the cargo capacities, which would erode the efficiency of shipment. Compared with traditional logistic and distribution providers, UAM is a better choice for E-commerce since it can offer a faster delivery and keep stable during the shipment, which in turn satisfies the consumers’ major concern and reduces the possibility of complaints and returns.
Figure6: Logistic and Distribution
Travel is many people’s favourable option to do in their leisure time, thereby the tourism market has huge potential for profits. UAM vehicles can also achieve an entertainment purpose for tourism by bringing tourists a wonder. Compared with airplanes for long distance travel, airplanes were just a tool for tourists to assist them in moving from one place to another place. During the flights, people always waste their time waiting for the departure, which is actually a buzzkill on a trip. However, UAM vehicles can lead tourists to arrive at the destination in an efficient way and to explore new sceneries where people seldom reach for a trip, which could spice up the trips.
Moreover, people tend to drive their own vehicles or take the public transport for their outings. But, it is commonplace and annoying that there is always traffic congestion on holidays. By contrast, UAM vehicles are not only faster but also able to avoid the embarrassing situation. People could have a better holiday vacation. In a nutshell, UAM could revitalise the originally saturated tourism market and provide opportunities to expand market value for tourism.
Figure7: Travel with a volar
Urban air mobility is considered a groundbreaking mode of transportation. Nevertheless, this concept of flying within urban areas is not just a sudden fantasy. In fact, the idea of VTOL (vertical take-off and landing) had sprouted for thousands of years and can be traced to Leonardo da Vinci's sketchbook. By the 20th century, the VTOL aircraft was flourishing while unmanned drones are becoming increasingly commonplace in the 21st century. Following the development in history, technology seems to continuously push forward the concept of urban air mobility. Nowadays, it has become mature enough to realise. The past sci-fi plots are no longer a work of imagination, urban air mobility is thriving at the right timing.
National Aeronautic and Space Administration (2018). Urban Air Mobility Airspace Integration Concepts and Considerations.
China Science Communication. Airplane. Baidu.
Markets and Markets (2019).Urban Air Mobility Market by Component (Infrastructure (Charging Stations, Vertiports, Traffic Management), Platform (Air Taxi, Personal Air Vehicle, Cargo Air Vehicle, Air Ambulance)), Operation, Range, and Region - Global Forecast to 2030.
Celine Hecbian (2018). Here’s How and Why Planes Have to Fly So High. TIME.
Karina Wright (2018). URBAN AIR MOBILITY ADDS A NEW DIMENSION TO TRAVEL. MITRE.
Arvind Gangoli Rao (2015). Jumbo City Flyer. The Netherlands: Delft University of Technology.
EHang (2020). The Future of Transportation: White Paper on Urban Air Mobility Systems.
International Civil Aviation Organization (2019). Accident Statistics.
Jacob Teter (2020). Tracking Transport 2020. Paris: International Energy Academy.
Healthwise Staff (2019). Harmful Noise Levels.
Fred Cohen (2011). Helicopter Noise. Hearing Health and Technology Matters.
Jacqueline Smith (2019). PREPARING FOR URBAN AIR MOBILITY INFRASTRUCTURE. Washington: American Association of Airport Executives.
Blair Allen (2019). NASA X Urban Air Mobility. NASA.
Katie Gatto (2011). Eurocopter X3: The world's fastest copter. PhysOrg.
EMDAT (2020): OFDA/CRED International Disaster Database, Université catholique de Louvain – Brussels – Belgium.
IMARC Group. Logistics Market: Global Industry Trends, Share, Size, Growth, Opportunity and Forecast 2020-2025.