Canadian electric vertical take-off and landing (eVTOL) developer Horizon Aircraft has concluded flight testing with its uncrewed X5 scaled demonstrator – achieving a full transition to wing-borne flight – keeping the company on track for a maiden sortie of a full-size prototype of its Cavorite X7 in 2027.
Horizon’s hybrid eVTOL architecture uses 14 electric fans for vertical lift – 10 in the wing and four in the canards – covered by sliding panels.
Remaining open during those manoeuvres, the panels are closed as the aircraft transitions to forward flight and thrust is delivered by the rear-mounted pusher propeller driven by a thermal engine.
Speaking to FlightGlobal as it announced the milestone, chief executive Brandon Robinson says Horizon has progressively approached the full transition in test flights since April, up until full closure of the fan covers was achieved “very recently”.
Although hailing the “critical technical milestone”, Robinson says the transition, achieved during a turn, was so smooth as to be almost “a non-event” – with the only surprise the rate at which the X5 accelerated once the panels were fully closed.
With its 6.7m (22ft) wingspan and 272kg (600lb) maximum take-off weight, the Cavorite X5 is around half the size of the six-passenger X7, which boasts respective figures of 15m and 2,500kg.
Robinson says Horizon has yet to decide whether to pursue an additional test campaign with the all-electric X5 as the focus shifts to the larger, piloted X7 and its hybrid powertrain.
“It’s the law of diminishing returns – we have learned enough that we want to go full-steam ahead with the full-scale aircraft,” he says.
Work on that asset is already under way at the firm’s base in Lindsay, Ontario, with component and system-level testing ongoing.
“We will do the detailed design review shortly and we’ll have a full-scale aircraft ready to ground test in 18-24 months,” he says, leading to a maiden sortie later in 2027.
Additionally, Horizon is “about to pull the trigger” on an order for a Pratt & Whitney Canada PT6A engine that will serve as the core of the hybrid powertrain, driving the rear propeller and charging the batteries.
While there is no formal agreement yet with P&WC to serve as a supplier to the programme, Robinson says the “PT6 line is close to perfect for us”, with the main debate over which variant – the -135 or -140 – is best suited to the role.
Initial sorties of the X7 prototype are likely to be in a conventional take-off and landing (CTOL) configuration, as Horizon builds data from those parts of the flight envelope.
In fact, the aircraft is likely to be assembled without its lift system in place, although it will be provisioned for its future installation.
Robinson says Horizon has sufficient funding for the next 12-18 months but continues to actively seek additional investment, with multiple options available to extend its cash runway.
