NASA-funded study by Georgia Tech finds untapped demand for shorter-distance flights in many under-served U.S. communities
By Anne Wainscott-Sargent
A shorter version of this article appeared in Avionics International.
Despite being on average less than 20 minutes away from a regional airport, most Americans spend time either driving to their final destination or driving to a large airport to fly on regional itineraries.
Regional airports are underutilized across the country for many reasons. The hub and spoke networks adopted by most airlines following the 1978 airline deregulation forces passengers to connect at about 20 hub-airports across the United Stated making short flights unattractive. In parallel, airlines have retired smaller turboprop aircraft that once efficiently connected these communities, in favor of larger regional jets that are better used on larger volume markets. As a result, airlines no longer have the equipment to profitably serve these communities.
“Regional air travel just doesn’t exist — those services have basically disappeared,” explains Cedric Justin, PhD, a member of the research faculty at Georgia Tech’s School of Aerospace Engineering and a commercial pilot. “It’s good stewardship of taxpayer money to bring services to those other airports. Taxpayers fund a lot of the airport infrastructure, whether or not it’s used by the general public.”
Out of 5,000 public airports with runways exceeding 3,000 feet, only 500 or just one in 10 are used by commercial air carriers, explains Justin.
“The consolidation of scheduled air services to and from a few big hubs adversely impacts the environmental footprint of aviation by creating air traffic congestion in and around large hubs, which are often operating at or near capacity,” he adds.
However, thanks to advances in aviation electric propulsion systems, a new market for regional air mobility could open up additional traveling options for U.S. travelers, finds a NASA-funded Georgia Tech study that predicts a resurgence in demand for regional flying.
Applying a mode choice model trading off door-to-door travel costs and travel-time savings, Georgia Tech researchers identified how many long-distance travelers taking journeys greater than 100 miles would opt to fly if they had an option to fly to and from convenient regional airports near their origin or destination. The study was published in the May 2022 edition of the journal, Transportation Research Part C: Emerging Technologies.
Unlike eVTOL aircraft, which take off from heliports in densely populated urban areas for very short flights within metro areas, regional air mobility services connect regions together using the network of existing airports and runways, and using fixed-wing aircraft seating between 9 and 30 passengers.
Built from light-weight material and envisioned to feature highly automated flightdecks, these aircraft will be powered by electric propulsion. Justin explains that autonomy technologies will simplify the operations of the aircraft, which will enable operators to reduce the number of pilots in the cockpit (many operators currently fly with more pilots than mandated by the FAA). Concurrently, the electrified powertrains have the potential to offer a step-change in energy efficiency while addressing many concerns about the impact of aviation on the climate.
“In each region of the United States that we have studied, we have seen significant demand for those new regional air services,” says Justin, noting that Georgia Tech’s model showed that regional air mobility could be a profitable option in hundreds of underserved communities.
The Northeast Corridor, for instance, is home to over 20% of the U.S. population but received commercial air services at only 80 airports. The Georgia Tech study indicates that operating a fleet of efficient electric and hybrid electric regional aircraft could bring profitable air services at over 140 airports, connecting many more communities to the rest of the world. Interestingly, the results indicate that over 60% of the passengers transported would fly on nonstop itineraries.
Overall, the Georgia Tech team identified over 4,200 Origin-destination or O&D markets connecting 980 different airports across the United States with a minimum frequency of two flights per day.
Since this new industry would rely on new electric and hybrid-electric powertrains, the environmental footprint from carbon emissions or from noise is much lower than conventional aircraft. That’s of interest to NASA’s Aeronautics Research Mission Directorate (ARMD) Portfolio Analysis and Management Office (PAMO), which funded much of the Georgia Tech research.
“The role of NASA is to develop technologies that are otherwise too risky for the private sector to develop on its own, and that will be used by industry,” explains Justin. “Is there demand and significant potential downstream opportunity for the industry to embrace these types of operations, provided that the technology has been de-risked?”
Results of the Georgia Tech study were shared with NASA leadership in mid-2022, and the agency has asked Justin to continue his work in collaboration with the National Renewable Energy Laboratory, tapped to find ways to power these airports using solar-powered electricity.
“The results we’ve seen thus far are very promising. Dr. Justin’s work really establishes an order-of-magnitude increase in this type of transportation if it can be enabled at the costs and with the technologies that he has modeled,” says Nick Borer, Ph.D., Advanced Concepts Group lead in the Aeronautics Systems Analysis Branch at NASA Langley Research Center.
“Working with the NREL, we see there are feasible changes that could be made for power delivery at these airports, especially a large increase in renewable energy that powers electrified aircraft,” continues Borer. “That is a very positive thing because it helps reduce the transportation carbon footprint, which is a big priority of the agency and of NASA Aeronautics.”
Justin expressed excitement for a future where fleets of electric-propulsion aircraft can serve more communities. One vehicle that has traditionally helped smaller communities maintain some air services to large hubs is the U.S. Essential Air Service (EAS) program. Passed into law as part of the Airline Deregulation Act in 1978 and operated by the Department of Transportation, the EAS program ensures small communities continue to be served by air carriers. However, it is expensive and in 2022 the EAS program spent $250 million to ensure communities remained connected.
Justin emphasizes that developing and maturing technologies that can be infused into state-of-the art regional aircraft has the potential to make many of these markets profitable by themselves without resorting to government subsidies.
Justin acknowledges that electric flight is a new technology, so it has to be certified and the public must consider it as safe as other modes of air travel before the market can take off. The first electric or hybrid-electric aircraft are expected to begin operating in the second half of this decade, with most industry experts predicting that the market won’t scale up before 2030.
Clearly, airlines have a path forward to leverage electric and autonomy technologies to deliver more affordable and more environmentally-friendly air services to the traveling public.
“The demand is there,” concludes Justin. “Certification of these new electric vehicles, the supporting (charging) infrastructure on the ground, and the ability to scale these operations remain the largest hurdles for the market.”