Last Monday, over the English Channel, a modified Saab 340B turboprop climbed past 30,000 feet with one of its propellers being spun, part of the time, by electricity. The flight lasted more than two hours. GE Aerospace announced it from the floor of the Farnborough air show on July 20, calling it the world’s first high-altitude hybrid-electric flight. NASA paid for a chunk of it. Boeing’s Aurora Flight Sciences built the nacelle. And the systems integrator that stitched it together and flew the hybrid legs of the ferry across the Atlantic was BETA Technologies, a Vermont startup better known for building battery-only aircraft.

That last detail is the tell. The company that made its name on pure battery flight was in the cockpit of a plane burning jet fuel to make electricity. If you have been following electric aviation through the stock tickers of Joby and Archer, you have been watching the wrong airplane.

Here is the number that reorders the picture. Since January 2020, the four companies that build the world’s jet engines, GE, Rolls-Royce, the Pratt & Whitney side of RTX, and France’s Safran, have been granted roughly 200 US patents on electric aircraft propulsion. The celebrated eVTOL startups, the ones that went public through SPACs and raised more than $15 billion between them, hold about 70. The incumbents out-file the upstarts by nearly three to one, in the one category everyone assumed the upstarts owned.

Break it down by company and it gets stranger. The Pratt and Collins businesses inside RTX account for 61 grants. GE has 57. Rolls-Royce, 54. Safran’s various engine and electrical units, 31. The single most prolific startup, Archer Aviation, has 33, which is genuinely respectable and beats every other new entrant, but Joby, the market’s darling, has 14. BETA has 12. Add up the entire venture-funded cohort and it still doesn’t reach what Pratt alone has been granted.

Two airplanes, not one

None of this would matter if everyone were patenting the same machine. They are not. This is the part that turns a spreadsheet into a story.

Read the actual claims and the two camps are building physically different aircraft. In the engine-makers’ filings, the recurring object is a gas turbine spinning an electric generator, which then feeds current to fans or rotors, with a control system deciding moment to moment how much of the turbine’s power goes to thrust and how much goes to making electricity. Rolls-Royce’s 2025 grants describe exactly this: a “power sharing module configured to control a ratio” of turbine energy split between driving the propeller and charging a bus. Pratt’s describe controllers that blend “a motor torque of the electric motor and an engine torque of the rotor” into one shaft. Safran’s describe a gas turbine driving a generator that supplies an AC busbar feeding a bank of electric thrusters. GE has one, granted in 2020, where the electric power comes from a fuel cell, and the water the fuel cell exhales is piped back into the turbine to cool it and raise its efficiency. Weird, specific, and entirely about squeezing more out of combustion.

Now read Joby and Archer. The object at the center of their claims is a battery. Joby’s power-system patent opens with “a plurality of batteries, a plurality of electric propulsion units, flight computers.” Archer’s recent grants are about inverter circuits converting a DC bus to the three-phase AC that drives a motor, and about fault handling when one of a dozen small rotors quits. There is no turbine anywhere. The energy comes off a pack, full stop.

The mechanistic split is almost clean enough to be a lab result. Sample the engine-makers’ electric-propulsion grants and two dozen describe a gas turbine driving a generator; essentially none name a battery pack as the aircraft’s energy source. Sample the startups’ and you get the mirror image: no turbines, batteries throughout. Delete the phrase “electric propulsion” from every patent in both piles and they still sort themselves into two bins, because they are two different theories of how to move an airplane.

Why the incumbents are hedging toward fire

The theory gap comes down to a brutal number that no amount of venture funding can move: energy density. A kilogram of jet fuel holds something like forty times the usable energy of a kilogram of the best lithium-ion cell. That ratio is why the eVTOL air taxi is real and the electric regional airliner is hard. Joby’s five-seat S4 gets about 150 miles on a charge in the brochure, and early commercial routes are penciled in at 30 to 40 miles, hops across a bay or from a downtown pad to the airport. That is a genuine market, and batteries can serve it. Stretch the mission to a 50-seat regional aircraft flying 500 miles and the battery that could do it would weigh more than the plane.

The engine makers know this arithmetic cold, because they have been living inside it for seventy years. So their bet, written into the patent record long before it showed up in press releases, is that the electric part of an airplane’s future is a supporting actor. The turbine still burns fuel and does most of the work. The electric machine trims the peaks, recovers energy, lets you shut down half the engine in cruise, and shaves fuel burn by a fifth to a third without asking physics for a miracle. Pratt’s Dash 8 demonstrator, which hit full power on the test stand in June 2025 with a one-megawatt Collins motor, a Pratt turboprop, and a modest 200-kilowatt-hour battery from Swiss supplier H55, is targeting 30 percent better fuel efficiency. Not zero emissions. Thirty percent, on an airplane that already exists, flying routes that already exist.

The rest of the incumbent field is running the same play. Rolls-Royce has ground-tested a hybrid system for a 19-seat commuter that can wire the turbine and the electric machine in series or in parallel depending on the phase of flight. Safran fired up its full-scale PHILEAS demonstrator in 2026 with two electric machines sized for short- and medium-range airliners, after its ENGINeUS motor became the first electric aircraft motor to earn EASA certification in 2025. Even Textron, which owns Bell and Cessna, holds 25 of these grants, an airframer quietly buying a seat at the propulsion table.

Who should be nervous

For an R&D director or an aerospace investor, the patent ledger reframes the whole sector. The story the market has been pricing, all-electric air taxis remake urban transport, is a bet on the smallest and least energy-hungry slice of aviation, the slice where batteries happen to work today. The story the engine makers have been quietly patenting is that they will electrify the large, profitable middle of aviation, regional and single-aisle, on their own timetable, using the combustion expertise nobody can replicate and an electric layer bolted on top. It is less thrilling. It also flies above 30,000 feet, which is where the money is.

Toyota clearly sees both stories. It has committed roughly $894 million to Joby and in July 2026 launched a manufacturing joint venture with it. Stellantis and United have poured comparable sums into Archer. That capital is buying the air-taxi lottery ticket. The patent stack suggests the incumbents already own the annuity.

The uncomfortable read for the startups is not that they are behind on patents, though most of them are. It is that the company flying GE’s hybrid demonstrator last week, the one that proved you can make electricity at altitude for two hours straight, was one of their own. When a battery-first startup shows up as the integrator on a fuel-burning airplane, the adjacent possible has already been chosen. It runs on kerosene, with an electric assist, and the people who will build it have been quietly patenting it for six years.

Method note. Counts come from 9.3M US utility patent grants sourced from USPTO bulk grant XML, filtered to grants issued between January 2020 and mid-June 2026 whose full text matches electric-aircraft-propulsion terminology. Company totals combine variant spellings and subsidiary names, so RTX includes Pratt & Whitney and Collins Aerospace, and Safran includes its engine and electrical units; a single patent can carry more than one assignee. The mechanistic split between turbine-generator and battery-source claims was checked by reading the representative claims and abstracts of the leading grants on both sides, not by keyword count alone. Program details, flight-test milestones, range figures, and funding totals are drawn from GE Aerospace, RTX and Pratt & Whitney, Rolls-Royce, and Safran announcements and from reporting by GreenAir, TechCrunch, and CNBC, all published between 2020 and July 2026. Patent grants describe what companies filed, not what they will build or ship.