Exclusive: Why Horizon’s Cavorite X7 VTOL can fly where electric air taxis cannot

Speaking exclusively to AGN, Horizon Aircraft CEO Brandon Robinson explains why the company believes rugged hybrid VTOL aircraft capable of IFR and icing operations will outperform many urban air taxi concepts in real-world service.

Cavorite X7 from Horizon aircraft, a hybrid VTOL aircraft

When you’re designing a VTOL for Canada, it’s got to be tough. That’s the message from Horizon Aircraft CEO Brandon Robinson, speaking exclusively to AGN about the development of its Cavorite X7 VTOL aircraft.

The Cavorite has already passed some key milestones. The large-scale prototype has completed full transition flights – a hover takeoff, transition to forward flight, back to hover and vertical landing – and the team is hard at work building the first full-size aircraft for flight testing.

When the Cavorite rolls out of the factory, it will mark a step change in advanced air mobility. Few aircraft using a comparable fan-in-wing architecture have progressed beyond experimental testing. The 1960’s Ryan XV-5 Vertifan showed promise, but ended up being too unstable in the transition to continue with.

The fan-in-wing is not just a novel vertical lift mechanism. It is also crucial to fulfil Cavorite’s role as a hardy, go-anywhere aircraft.

“We’re designing, from the very start, a really tough machine,” Brandon told AGN.

Why Horizon’s Cavorite differs from typical eVTOL air taxis

While many AAM companies pursue all-electric urban air taxi concepts, Horizon’s Cavorite is designed with utility in mind. From search and rescue and medical evacuations to passenger and cargo transport, the built-in-Canada aircraft targets operations in the toughest environments.

The secret sauce that will allow Horizon to deliver this is that unique fan-in-wing architecture. Unlike multicopter-style eVTOLs, Cavorite uses fans hidden inside the wings to provide vertical lift and landing. Once in the air, a traditional pusher prop provides forward momentum, while the fans are once again hidden by the wing surface.

Horizon Aircraft Cavorite X7 VTOL with fans open
Photo: Horizon Aircraft
Horizon Aircraft Cavorite X7 VTOL with fans closed
Photo: Horizon Aircraft

“The all-electric VTOL companies have these massive tilt rotor mechanisms,” Robinson says. “Those rotor mechanisms are horrendously expensive, and they will require significant inspection cycles.”

In contrast, the Cavorite has been engineered to behave more like a light aircraft in flight, with a lifting solution that is both simple and incredibly clever. As well as avoiding the use of heavy, complex tiltrotor mechanisms, the CEO says this design will also be cheaper and easier to maintain.

“Our blades are an order of magnitude cheaper to maintain,” Robinson adds. “They’re all fixed pitch … you can just drop one out and put another one in.”

Icing and bad weather could limit many eVTOLs

Having those fans encased in the wing during flight also solves another issue – ice. Large tiltrotors that pass through the air at an angle are more susceptible to icing than a traditional vertically mounted fan, which means eVTOLs may need to be certified for cold-weather operations, even when flying in warm climates.

“I think it’s underestimated the operational restriction imposed on vehicles that can only fly in good weather and warm weather,” Robinson says. “Even if you’re flying from a warm airport, once you get up to 5,000 feet in the air, the air temperature will be freezing.”

Cavorite X7 from Horizon aircraft, a hybrid VTOL aircraft
Photo: Horizon Aircraft

Most urban air taxi developers are targeting relatively low-altitude operations below typical regional aviation corridors, often between 1,000 and 4,000 feet. Nevertheless, in busy cities, where other air routes need to be avoided, they may have to fly higher on occasion.

“Anyone that has an open rotor architecture will find anti-ice horrendously complicated,” Robinson explains. There’s only a handful of helicopters in the world that are capable of flying in clouds and flying into known icing, and even then, they avoid it at all costs, because if you get ice built up on those rotor systems, it’s game over.”

Horizon Aircraft, on the other hand, is building the Cavorite to fly much higher. It is also developing the aircraft to fly in known icing (FIKI) conditions, targeting certification for all-weather, instrument flight rules (IFR) operations.

“We’re gonna keep it below 10,000 feet,” says Robinson. “It’ll be able to fly much, much higher, but you start needing specialised oxygen equipment and such. On a ferry flight with no passengers, it would easily get up to 18,000 feet, but for operations, we’ll keep it between 5,000 and 10,000 feet.”

horizon aircraft cavorite x7 medical variant
Photo: Horizon Aircraft

This has implications for AAM airspace design as well. While regulators are evaluating entirely new low-altitude airspace management solutions, the Cavorite will not require such concessions.

“When you can fly in clouds, and you can use normal commercial air routes, you don’t have to reinvent the wheel and establish all of these new low-level route structures,” he said. “You can just use the highway in the sky that already exists.”

Horizon’s anti-icing research could support wider AAM operations

One of Horizon’s strongest differentiators may ultimately be its focus on IFR certification and flight into icing conditions, areas that many eVTOL developers rarely discuss publicly. But the company is not just working on solutions for its own VTOL aircraft.

The company is currently conducting anti-icing and environmental testing work through Canada’s Initiative for Sustainable Aviation Technology (INSAT), supported by a CA$10.4 million grant.

Graphic showing airflow around open fans for lift of Horizon Aircraft's Cavorite X7 VTOL
Photo: Horizon Aircraft

“We’ll build a wing section, we’ll test icephobic coatings, electro thermal coatings, bleed air systems, and we’ll see what works best,” Robinson explains. “We can put it in a wind tunnel and bring it down to minus 40 degrees, and throw all sorts of freezing precipitation at it.”

Horizon believes the real challenge for advanced air mobility is no longer simply proving vertical flight, but proving aircraft can operate safely and economically in the same conditions as conventional aviation. The company’s continued investment and research into all-weather capabilities is what the CEO believes will separate the Cavorite from limited-use urban air taxis.

“They’ll do some great work over shorter distances,” he said. “And we can do everything else.”

Featured image: Horizon Aircraft

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