Aircraft

Russian unmanned, long-range, hybrid multirotor wants to do the heavy lifting

Russian unmanned, long-range, hybrid multirotor wants to do the heavy lifting
ARDN's SKYF on a recent test flight
ARDN's SKYF on a recent test flight
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ARDN's SKYF: on display at an expo
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ARDN's SKYF: on display at an expo
ARDN's SKYF: on display at a Russian expo
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ARDN's SKYF: on display at a Russian expo
ARDN's SKYF: manufacturing facility
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ARDN's SKYF: manufacturing facility
ARDN's SKYF: belt drive lift props
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ARDN's SKYF: belt drive lift props
ARDN's SKYF: fuel tank
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ARDN's SKYF: fuel tank
ARDN's SKYF: gasoline engine provides heavy lift and endurance
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ARDN's SKYF: gasoline engine provides heavy lift and endurance
ARDN's SKYF: fine control, stabilization and steering come from twin electric props at each corner
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ARDN's SKYF: fine control, stabilization and steering come from twin electric props at each corner
ARDN's SKYF: electric meets combustion to highlight the advantages of each
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ARDN's SKYF: electric meets combustion to highlight the advantages of each
ARDN's SKYF: 17 x 7.2 feet makes this a decent sized airframe
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ARDN's SKYF: 17 x 7.2 feet makes this a decent sized airframe
ARDN's SKYF: folds for transport and storage
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ARDN's SKYF: folds for transport and storage
ARDN's SKYF: deploys from a container or trailer
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ARDN's SKYF: deploys from a container or trailer
ARDN's SKYF: cargo delivery where wheels can't take you
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ARDN's SKYF: cargo delivery where wheels can't take you
ARDN's SKYF: potential for offshore operations and deliveries
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ARDN's SKYF: potential for offshore operations and deliveries
ARDN's SKYF: potential for asset inspection and repairs
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ARDN's SKYF: potential for asset inspection and repairs
ARDN's SKYF: potential for disaster relief
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ARDN's SKYF: potential for disaster relief
ARDN's SKYF: potential for providing offshore operations and deliveries for a fraction of the cost of a chopper
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ARDN's SKYF: potential for providing offshore operations and deliveries for a fraction of the cost of a chopper
ARDN's SKYF: logistics as the crow flies
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ARDN's SKYF: logistics as the crow flies
ARDN's SKYF: potential for firefighting applications
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ARDN's SKYF: potential for firefighting applications
ARDN's SKYF: fine control, stabilization and steering come from twin electric props at each corner
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ARDN's SKYF: fine control, stabilization and steering come from twin electric props at each corner
ARDN's SKYF on a recent test flight
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ARDN's SKYF on a recent test flight
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This chunky multirotor can carry up to a 400-lb payload, and fly for up to eight hours. The SKYF uses the power and endurance of gasoline engines for lift, and the instant torque of electric motors for control and stabilization, resulting in a heavy-lift, affordable multirotor using today's tech.

It seems inevitable that large, electric multirotors are going to play a key role in the coming decades, and not just as flying cars. Much simpler, cheaper and easier to fly than helicopters, these jumbo drones are going to revolutionize all sorts of transport, delivery and cargo industries. Not yet, though, because of the same thing that's holding electric cars, trucks and motorcycles to the top end of the market – batteries are still too expensive, too slow to charge, and too heavy for long range utility in aircraft.

And gasoline engines don't look like a very effective substitute at this stage. While they can deliver terrific power, endurance and allow quick refueling, multirotor airframes need to be able to make lots of motor speed changes in quick succession to remain stable in the air. Gasoline engines are slow to react, and complex to manage since they deliver differing amounts of power depending on how fast they're spinning. That's why multirotor drones never really took off, if you'll excuse the pun, until lithium batteries became ubiquitous.

ARDN's SKYF: fine control, stabilization and steering come from twin electric props at each corner
ARDN's SKYF: fine control, stabilization and steering come from twin electric props at each corner

All of this is what makes bridging technology like the SKYF all the more interesting. Russia's ARDN Technology has built a large multirotor platform that uses a hybrid propulsion system to deliver heavy-lift capacity and long-endurance flights, right now, using proven equipment.

The SKYF airframe takes advantage of the lifting power and endurance of a gasoline engine to drive its two main lift props, and then uses four sets of coaxial twin props with electric motors at the corners of its boxy frame to stabilize and steer it. By separating the lift from the control, the advantages of both motors can shine.

ARDN's SKYF: potential for offshore operations and deliveries
ARDN's SKYF: potential for offshore operations and deliveries

According to ARDN, this combination allows a 400-lb (181-kg) payload capacity and a range up to 350 km (217 mi) or eight hours in the air, for a decent-sized multirotor that's suitable for a range of industrial jobs, from precise, automated crop dusting to fire fighting and cargo work where wheels can't take you.

You won't be sitting people on this one, at least not flying carpet style, thanks to those two large props. But there's no reason it couldn't be fitted with an undercarriage in the future to become a manned aircraft. For the moment, though, flights of a prototype are automated, with the airframe receiving encrypted instructions from a flight dispatch center.

ARDN's SKYF: potential for firefighting applications
ARDN's SKYF: potential for firefighting applications

In practical terms, the company claims the SKYF costs around US$150 an hour to run, which is an order of magnitude less than a helicopter. It can also fold down small enough that two will fit in a 20-ft cargo container. Setup takes around 10 minutes and the overall dimensions work out at 5.2 x 2.2 m (17 x 7.2 ft). The operational ceiling is around 10,000 ft, and its autonomous flight controller operates within a precision of around 30 cm (11.8 in).

An airframe like the SKYF gives companies the chance to get a head start on long-range, heavy-lift multirotor development while the rest of the world waits for batteries to catch up. Seems like a solid idea to us.

Here's a video explaining the tech, and showing early flight tests.

SKYF operating principle

Source: SKYF

View gallery - 20 images
4 comments
4 comments
Reece Agland
Cool combo. Though i wonder if they should use mini turbines to provide electrical power.
Mzungu_Mkubwa
It is refreshing to finally see some folks use some reasonable logic to the design of a VTOL flight system! It's about time! I think this I/C design has its place, while holding the promise of scaling this up using turbine power-plants for larger systems. I'm surprised that the military is not all over this as a supplement and eventual replacement for heavy-lift helicopter cargo systems (costly to produce and operate.) They are already comfortable flying fixed-wing drones for any number of important missions, so why not lean on them for the more mundane? I'd also bet that this would prove reliable enough to eventually carry human "cargo" as well!
ikarus342000
Typical Russian approach. Very practical. By the way in the spec on the video the lift is 880 pounds (400kg). This could be a commercial success
Marco McClean
Lifts 800 pounds. So all the concept photoshops look possible but the firehose image. A firehose gives more than 200 pounds of thrust. Its stream would have to be angled up through the lift blades for the drone to maintain position, with the drone tilted hard over toward the flaming building, and with a timed interrupter mechanism to not wreck the blades and shoot itself out of the sky. Or the interrupter could be on the ground to save flying weight.
Or maybe just do it the way it is in the image but waste half the water in a stream in the opposite direction, over the crowd of rescuers, to cancel out the lateral thrust.
Also, hmm, the hose and all the water in it weigh something.
Maybe instead of a drone they could use some kind of bazooka from a building across the way, shooting concentrated fire retardant chemicals. Or use the drone to toss in fire-retardant-filled glass Xmas ornaments like the ones they used to sell to farmers. Fire grenades, they called them.