To minimise the risk of spread of COVID-19, walk-in services at The URA Centre are unavailable until further notice, and members of the public are to use our e-services. Visits to the Singapore City Gallery are by appointment only. Read more here

Up and Away: Urban Mobility in the Sky

  Published: 26 November 2017
  Theme: Mobility

“Imagine travelling from San Francisco’s Marina to work in downtown San Jose — a drive that would normally occupy the better part of two hours — in only 15 minutes,” enthuses UBER Elevate in its study, Fast-Forwarding to a Future of On-Demand Urban Air Transportation1.

UBER Elevate is one of a handful of companies working to make urban air mobility (UAM) possible for cities. Other manufacturers of vertical take-off and landing (VTOL) aircraft include European aerospace conglomerate Airbus2 and Chinese drone-maker Ehang3



Like almost all UAM vehicles, the Ehang184, by Ehang, is modelled on drone technology. (Image source: Ehang)

Urban mobility
Airbus’s Pop Up is a modular air and ground passenger concept. (Image source: Airbus)

Electric-powered and using multiple rotors, VTOL aircrafts’ airborne capabilities are based on drones, rather than helicopters or light aircraft.

A common viewpoint among industry players is that as a mode of transport, UAM could be ready for widespread deployment in the mid- to long-term. “While the vision portrayed is ambitious, we believe it is achievable in the coming decade if all the key actors in the VTOL ecosystem — regulators, vehicle designers, communities, cities, and network operators — collaborate effectively,” UBER Elevate states. 

Benefits to Cities

UAM present three core benefits to cities:

An additional mode of transport: The deployment of UAM presents a complementary mode of transport to road and rail, and could help to reduce congestion on roads and overcrowding on metro systems during peak hours 

Less land usage: VTOL aircraft will also alleviate land use pressures as they could tap on underutilised air space above existing congested roads. This could reduce the need to build new roads or expand existing ones  — a noteworthy opportunity for all cities, especially those with limited land space like Singapore 

Less travel time: VTOL aircraft will bring about more direct routes between nodes, making journeys quicker than other forms of transport

“UAM is an exciting concept, since no roads are needed and it is potentially a faster mode of travel for some commute routes,” says Chris Leck, Director of the Futures Division at Singapore's Ministry of Transport. “It is now commercially viable for a few reasons: first, breakthroughs in key technology such as battery and propulsion methods; second, advancements in manufacturing leading to lower production costs; and third, the rise of new business models such as ride-sharing to make VTOL rides more affordable.”

Technology Barriers

Barriers to adoption remain. Battery technology is currently insufficient for long and/or repeated journeys. This is exacerbated by the fact that recharging batteries takes several hours and this may be too slow to support high-frequency operations. 

Safety, too, is a core concern. Vehicular safety must incorporate features that are fully developed today, such as distributed electric propulsion and emergency recovery systems. Given that in the longer term they will be unmanned and autonomous, detect-and-collision avoidance technologies must be developed, explains Leck. Research unearthing the impact of variable weather conditions on VTOL aircraft is also limited.

Other areas of concern include go-to-market costs, vehicle performance and reliability, and ownership — who ensures the safety of both the passengers and passers-by, and who owns and operates the aircraft: the public or private sector, or a partnership involving both? These issues must too be resolved before widespread deployment of VTOL aircraft.


With UAM predicted to become a reality in the future, city planners must prepare for its implementation early. 

First, cities need to decide whether they want to allow aircrafts to fly freely between two destinations, or if they prefer routing UAM to fixed routes that correspond to current transportation networks. 

“UAM will likely be based on aerial corridors with separation standards similar to manned aviation today,” explains Leck. “One possibility would be for such vehicles to fly existing helicopter routes in Singapore that have already been delineated. Subsequently, as technology advances, we could expand to more overland routes, and over more densely populated areas.”

Second, urban planners must consider potential take-off and landing areas as well as the heights of buildings, and how they compare with one another. For instance, should buildings be of a uniform height in order to make flying spaces easier to navigate; which buildings should house landing pads; where will VTOL aircraft park; will these landing pads have recharging equipment or will these be located elsewhere? Research could help solve these issues and recommend building design guidelines such as height of developments and the number of landing pads per square kilometre. 

Third, planners must consider how take-off and landing areas are planned and designed to ensure that they are accessible, safe, secure, and support intermodal linkages. Studies should also be conducted to determine how potential nuisances caused by UAM, such as noise and loss of privacy in high-rise developments can be minimised. 

Rules of the Sky

To successfully implement UAM, cities will have to introduce regulations for VTOL aircrafts. Air traffic control must prepare for a significant rise in the number of aircraft in the sky. 

“A new paradigm of airspace utilisation will be needed to overcome both geographical and infrastructural limitations. The approach would be to work towards segregation, and to allow VTOL aircraft to be used only when they do not interfere with the airspace for traditional aviation,” explains Leck. 

“But this approach is not sustainable in the long run, especially when airspace is limited and over a dense urban landscape. Successful operations will require supporting services such as meteorological forecasts, notifications of surrounding obstacles and air traffic,” he cautions.

Achieving Mass Adoption

While studies by industry leaders examine the plausibility of UAM, this mode of transport remains in its infancy. Further research and partnership by all stakeholders will be required; regulators, industry leaders and government bodies must come together to uncover the best way to regulate and implement UAM. These include identifying the opportunities, challenges, and solutions for the planning and design of urban infrastructure to support UAM — indeed, these are areas currently being explored by a research collaboration between Airbus and Singapore.

“The urban air transportation ecosystem will only be successful with the participation of entrepreneurial vehicle manufacturers, city and national officials from across the globe, regulators, users and communities keen to interact with one another to understand how the ecosystem can shape the future of on-demand urban air transportation,” concludes UBER Elevate.