Horizon s Cavorite X7 Hybrid electric Aircraft Offers a Different VTOL Recipe FutureFlight

Canadian startup Horizon has reported progress with its Kaverit X7 hybrid electric VTOL aircraft. At the recent Verticon show, AIN's Editor-in-Chief Matt Thurber heard about what the company says sets it apart from rivals. So this is a somewhat unusual design with fans in the wing. Tell us why that architecture was selected. Well there's a number of benefits to putting the fans in the wing. If you're using a ducted fan of any sort, you gain efficiency for power laydown. So you don't have any losses for the fuselage being underneath the main rotor or something like that with a helicopter. That typically results in 15% thrust loss in the vertical. You put the fans into the wing, you actually have a gain from low pressure area on the top of the wing, even in the hover. But it's not that efficient if you want to move forward with the fans in the wing, is it? So how is that? No, but it is. So here's the trick. You see what that does with the front panel of the wing moving forward. We have one third of the wing in front of the fans. So what we end up with is a blown boundary layer on the front third, which means we create lift below stall speed. So give us a little more detail about how this all works together to give you the efficiency you need to get the kind of range you're shooting for. So really the good thing about the propulsion system is that each item is optimized for its phase of flight. So that means that the lift fans are all optimized for the hover. They are fixed pitch optimized for vertical lift and one rpm only. And then all of the maneuver in the hover is thrust vectoring with gridded vanes that deflect the thrust underneath the outboard fans. Then when we accelerate away with the PT6 with this variable pitch prop, it's a pusher. So we don't need to add more power to the lift fans because the lift vector remains vertically down. And as we accelerate away, the lift fans trim back their rpm as the wing produces lift. And then when the wing panels close, you've reduced your drag four times over and you can accelerate. And you really accelerate. We had some challenges with the speed of acceleration on our test flying. The forward sweep in the wings takes away wingtip vortices. So we have less drag than a conventional fixed wing aircraft coupled with a rear lifting deck that gives us a bit of a blended wing body approach to it. So what kind of performance is expected from the full size X7? So we're looking as advertised really at our sort of 500 mile range or 800 kilometers. And then we're looking at a 200 knot plus cruise speed depending on the amount of installed horsepower with the PT6 because users can choose the PT6 that they put in and trade off between vertical lift weight because a higher horsepower engine is slightly heavier. And if you want to do that, you can do that and get more speed. But there's also a battery system to power the lift fans, correct? There is. And what we've done is we've put them in the leading edge panel for center gravity reasons for a transition to hover, but also for the shortest wires possible to the motor controllers and then into the motors to reduce losses. And there's only about 400 pounds of battery in the whole 6,000 pound aircraft. So for a typical mission, how much time would we spend during takeoff in the vertical phase before you transition? So it's literally pop up and then just get the motor going to push out of the hover into forward flight with a level effort. That uses about somewhere between 10 and 12 percent of the battery capacity. So we have probably at least nine vertical events within the battery capacity of the aircraft. And if they ever fail at any point, we can go to a runway because we're fully conventional runway capable with wings open or wings closed. But the PT6 engine itself will be able to charge up the batteries as well, correct? Yes. So on climb out from vertical takeoff, the PT6 will charge the batteries throughout that whole event. And it will be a few minutes before the batteries are fully back up to full charge. OK, so what are we looking at in terms of timeline for this program? So this year we've ordered the demonstrators full scale fuselage and wings. They'll be delivered in the coming months. You'll be able to climb into the airplane and crawl all over it later this year. And then we'll have power on at some point and then flight test to start immediately after power on. And have suppliers been selected and can you identify any of them? Well, I'd really offer that as an opportunity to suppliers that there are a number of others who can get into our supply chain for the certified aircraft. For the demonstrator, we have chosen a number of suppliers like RAMP for the fuselage, MT Propellers for the propeller, Pratt & Whitney for the PT6 and North Aircraft for the wings. So we have a number of suppliers already selected for the demonstrator. And then as we transition into production, there's a new opportunity for supply chains to be established with many supply companies. For this new generation vertical takeoff and landing aircraft, Horizon has been influenced by flight control technology already in use with F-35 fighters operating from aircraft carriers. So what we're looking at really within the flight controls is something similar to the F-35B in the way that the flight controls work, which is to keep it seamless for the pilot. And the control is always doing the same thing as you transition in and out of the hover towards forward flight. But in forward flight, it'll handle exactly like a conventional airplane with a PT6 like a Cessna Caravan or a PC-12. That's an interesting point. The control is always doing the same thing because in a tilt rotor, you have different controls doing different things. And it takes a lot to wrap your brain around that. So, you know, with Sea Harrier, we had four variables. We had stick in two axes. We had the throttle. And then we have the nozzle lever. And then we also had rudders. We actually had five, but you never really use the rudders, to be honest. So with four variables, that reduces it down to less than 1% of pilots that can do that. So then the Lightning brought that forward really by reducing the number of variables down to two because there's height hold, there's position hold. There's all of these other functionalities that are possible now with new flight control systems that reduce the number of variables. And, you know, from my Super Horn experience with Magic Carpet and Precision Landing Mode, even an approach to an aircraft carrier was reduced from three variables that were interdependent with compensating inputs from the other variables when you varied one of the others down to two with Precision Landing Mode. And that's what we're trying to achieve really with the Horizon aircraft, where if we arrive in the hover, then it should stay where you left it. Horizon is targeting multiple different civil and military applications for the Caveret X-7. It says that optimized operating costs will give it a competitive edge compared with existing aircraft. So what is the target market for the Horizon aircraft? So one of the things that Lessor has told me is that what they don't like is fleets within fleets. So what we're doing is making the aircraft suitable for most roles as an inherent capacity. So every aircraft will have a cargo floor. Every aircraft will have an EMS door to allow the gurney in on rails to come into the right position. And every aircraft will be capable of being VIP. Every aircraft will be capable of being regional transport. So all of that really basically means is that what we're trying to do is reduce different sectors of use to role changes. And some of the other things that we can do in the future are to give it autonomy for cargo. For example, in Canada, we suffer from a shortage of pilots for bush pilots. So if we're going to support remote communities or improve the internal lines for dual use in Canada, we need an autonomy option. So that's probably something in the future. So presumably you're looking at defense applications as well. Yeah, we have a couple of features that really make this aircraft suitable for defense beyond the role change capacity. And that is folding wings. The wings fold forward and you can fit two in a C-17 or two on a destroyer or a frigate. So we've sized it appropriately to fit ships. So we see the market as being complementary to V-22, complementary to V-75 because it can keep up because no helicopter out there can keep up with those new aircraft. And the other sort of capacity we built into the airplane is air refueling. And the fundamental sort of signatures of the airplane are reduced from a helicopter as well. We're 20 times quieter than the helicopter in overflight, seven times quieter in the hover. Radar, we don't have a big dopper returning main rotor. We just have the pusher prop, which is much smaller. And for infrared, the exhaust of the PT-6 are shielded from many angles by the rear deck and twin tails. But what about operating costs? Yeah, so one of the things that we've optimized is operating costs of the aircraft. By putting away the fans that make you hover, we reduce drag by four times over, reducing fuel burn four times over. And that compounded with other benefits of the aircraft results in about one quarter of the operating costs of a twin engine helicopter over the same range. But the other killer really on cost is double the speed. You can do twice as many sectors in one day. Well, we're tracking new aircraft like this all the time at AIN. 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