A two-seat hybrid-electric aircraft has landed on a pier in New York normally reserved for helicopters. The demonstration is a neat piece of aerodynamics with obvious appeal for a country short of runways. The commercial aircraft it is meant to herald has yet to fly.
On the morning of 26 October, a small yellow aeroplane approached Lower Manhattan at about the speed of a city bus, touched down on a pier in the East River and stopped within a few lengths of itself. It later took off again from the same spot. The Downtown Skyport on Pier 6 has handled helicopters since 1960. According to the aircraft’s maker, the Virginia company Electra, this is believed to be the first time a fixed-wing aeroplane without vertical take-off ability has landed there. Aviation Week & Space Technology put the flight on the cover of its issue of 2 November.
How a wing is made to work at 30 miles an hour
The aircraft, a two-seat demonstrator designated EL2 and nicknamed Goldfinch, relies on a principle called blown lift. Eight small electric motors are spaced along the leading edge of the wing. Their propellers push fast-moving air across the entire wing and over large flaps that deflect it downward. The wing therefore experiences a strong airflow even when the aeroplane itself is moving slowly, and generates several times the lift it would otherwise produce.
The effect is to lower the speed at which the aircraft can fly safely. The American pilots’ association AOPA reported an approach speed of about 30 miles an hour, roughly 48 kilometres an hour. Since the distance needed to land rises steeply with speed, a slow approach translates into a very short ground roll. Electra says its design can take off and land in about 150 feet, or 46 metres. The heliport’s pad, according to Aviation International News, measures 62 feet by 62 feet.
Blown lift is not new. Aerodynamicists explored it with jet and turboprop aircraft from the 1950s onward. What has changed is that compact electric motors make it practical to distribute many small propellers along a wing and control each one precisely.
Why hybrid, not battery
The propulsion is hybrid-electric. A small turbine generator produces electricity in flight and, together with a battery, feeds the eight motors. The arrangement sidesteps the central weakness of pure battery aircraft, which is limited range and long recharging time, while retaining the benefits of electric drive for the short, power-hungry moments of take-off and landing. It also means the aircraft does not depend on charging equipment at its destination.
The EL2 first flew on battery power in November 2023 and as a hybrid later that month. In August this year it took part in flights linking airports in Virginia, New Jersey and Pennsylvania under a Federal Aviation Administration pilot programme for integrating new types of aircraft.
The aircraft that matters has not flown
The demonstrator exists to prove the concept for a much larger product: the EL9, a nine-passenger aircraft that Electra aims to put into service around 2030. The company argues that an aeroplane able to use heliports, short strips, piers and even barges could offer direct regional flights from city centres, with the economics of a fixed-wing aircraft, which carries more and costs less per seat than a helicopter or an electric air taxi.
Its own market study estimates that a trip from New York to Boston could be about three hours and 45 minutes shorter door to door, and New York to Washington about three and a half hours shorter. Those are company projections, not measurements from an operating service.
Sober reading is required on several counts. The EL9 has not yet flown. Scaling blown lift from a two-seater to a nine-seat commercial aircraft raises questions that only flight testing will answer, including how the aeroplane behaves if one or more motors fail at very low speed, when it is depending on them for lift as well as thrust. Certification of a novel configuration is slow and expensive. A demonstration by test pilots in good weather is also different from scheduled operations in gusting winds between tall buildings, and urban sites bring noise and community concerns of their own.
A different bet from the air taxi
The landing is best understood as one side of an argument within the industry. Most of the money in advanced air mobility has gone into electric vertical take-off aircraft, which rise like helicopters. Vertical flight is convenient but costly in energy, which limits payload and range on batteries. Electra’s proposition is that an extremely short runway is almost as useful as none, and that accepting 46 metres of ground roll buys the range, payload and simplicity of a wing.
The Indian angle
For India the second market is the more interesting. The regional connectivity scheme, UDAN, has reopened dozens of small airports, but many routes struggle because the available aircraft need runways of a kilometre or more and enough passengers to fill 70 seats. Much of the country’s hill, island and interior geography has no room for such runways. A nine-seat aircraft able to use a strip shorter than a football pitch, a helipad or a riverside platform could in principle serve the north-eastern states, the Himalayan districts, Lakshadweep and the Andamans, as well as medical evacuation and cargo.
Indian operators have noticed. The charter company JetSetGo announced a letter of intent in January 2024 for Electra’s short-take-off aircraft as part of a wider plan for advanced air mobility services. A letter of intent is not a firm order, and delivery depends on certification in the United States and then validation by India’s aviation regulator, which is still developing its rules for this class of aircraft.
The measured verdict
The Manhattan flight shows that the aerodynamics work at demonstrator scale and that a fixed-wing aircraft can fit into a space built for helicopters. It does not yet show that a certified passenger aircraft can do so every day at a price people will pay. That evidence will come, if it comes, when the EL9 flies.
– Rashmi M
