Aircraft

Joby's wild 16-rotor convertible aircraft for long-range, high-speed, electric VTOL commuting

Joby's wild 16-rotor convertib...
Joby conceives the S2 VTOL tilt-rotor aircraft as a kind of commuter aircraft
Joby conceives the S2 VTOL tilt-rotor aircraft as a kind of commuter aircraft
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Joby S2 VTOL tilt-rotor aircraft promises 200-mile range with a 200 mph top speed
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Joby S2 VTOL tilt-rotor aircraft promises 200-mile range with a 200 mph top speed
In cruise configuration, the Joby S2 VTOL tilt-rotor aircraft's 12 tilting VTOL propellers fold away into aerodynamic bullet shapes
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In cruise configuration, the Joby S2 VTOL tilt-rotor aircraft's 12 tilting VTOL propellers fold away into aerodynamic bullet shapes
Joby S2 VTOL tilt-rotor aircraft: faster and more efficient than a helicopter, with the same vertical takeoff and hover abilities
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Joby S2 VTOL tilt-rotor aircraft: faster and more efficient than a helicopter, with the same vertical takeoff and hover abilities
Joby conceives the S2 VTOL tilt-rotor aircraft as a kind of commuter aircraft
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Joby conceives the S2 VTOL tilt-rotor aircraft as a kind of commuter aircraft
The Joby S2 VTOL tilt-rotor aircraft takes off and hovers like a multirotor, then transforms to deliver the long range and high speeds of a fixed wing
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The Joby S2 VTOL tilt-rotor aircraft takes off and hovers like a multirotor, then transforms to deliver the long range and high speeds of a fixed wing
The Joby S2 VTOL tilt-rotor aircraft's 12 tilting rotors handle takeoff, hover and landing, while four cruise props take over at cruise speeds for efficiency
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The Joby S2 VTOL tilt-rotor aircraft's 12 tilting rotors handle takeoff, hover and landing, while four cruise props take over at cruise speeds for efficiency
The Joby S2 VTOL tilt-rotor aircraft's rotors folded away in cruise configuration
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The Joby S2 VTOL tilt-rotor aircraft's rotors folded away in cruise configuration
Joby S2 VTOL tilt-rotor aircraft: rotors pointed upward in takeoff/landing configuration
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Joby S2 VTOL tilt-rotor aircraft: rotors pointed upward in takeoff/landing configuration
Joby S2 VTOL tilt-rotor aircraft: the convenience of a multirotor with the range of a fixed wing and the efficiency of electric propulsion
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Joby S2 VTOL tilt-rotor aircraft: the convenience of a multirotor with the range of a fixed wing and the efficiency of electric propulsion

Personal electric VTOL (vertical take off and landing) commuting may not be far off, thanks to accelerating improvements in battery technology. Joby Aviation has put forward an incredible two-seater plane concept that uses 12 tilting electric propellers to provide multirotor-style balanced VTOL capabilities. Once it reaches cruising speeds, these rotors fold away into aerodynamic bullet shapes, and the aircraft can reach speeds of up to 200 mph (322 km/h) and ranges of up to 200 miles using four additional cruise-optimized props on the backs of the wings and tail fins.

Serial entrepreneur JoeBen Bevirt made his name selling innovative bendy camera accessories under the Joby brand. Nifty jiggers, I've got a Gorillapod myself. In 2008, he branched out into renewable energy with a focus on airborne wind turbines under the Joby Energy brand.

The control systems and electric generators required to get the flying wind generators running produced a lot of technology relevant to another rapidly developing field – electric aviation – so Joby Aviation and Joby Motors were born.

The aviation company's first aircraft concept is an absolute cracker in the form of an electric twin-seat tilt-rotor capable of VTOL as well as high speed, long-range flight.

The Joby S2 VTOL tilt-rotor aircraft's 12 tilting rotors handle takeoff, hover and landing, while four cruise props take over at cruise speeds for efficiency
The Joby S2 VTOL tilt-rotor aircraft's 12 tilting rotors handle takeoff, hover and landing, while four cruise props take over at cruise speeds for efficiency

Taking advantage of the speed, responsiveness and efficiency of electric motors, the Joby S2 features no less than 16 propellers along its thin, forward-swept wings and V-shaped tail. Because electric motors are so quick and torquey, they're fixed-pitch propellers requiring no collective or cyclic control like that used by helicopters.

Twelve of those props are tilting designs that can face upwards to provide balanced, multirotor-styled vertical lift for takeoff and landing, then tilt forward to develop forward thrust and get you moving. They're also designed for low tip speeds to keep takeoff as quiet as possible, and having 12 of them on board gives you plenty of redundancy if a motor or two fails.

This kind of tilting electric multirotor action has recently been proven by NASA's GL-10 "Greased Lightning" prototype, but once you reach cruising speed, the Joby S2 has another trick up its sleeve; all 12 tilting props fold away into bullet-shaped pods for minimal drag, and four thinner rotors take over. These are cruise-optimized fixed-pitch propellers located on the backs of the wingtips and tailfins.

Joby S2 VTOL tilt-rotor aircraft: the convenience of a multirotor with the range of a fixed wing and the efficiency of electric propulsion
Joby S2 VTOL tilt-rotor aircraft: the convenience of a multirotor with the range of a fixed wing and the efficiency of electric propulsion

In cruise configuration, the S2 is designed for a 200 mph (322 km/h) top speed, which is much higher than, for example, the 120 mph (193 km/h) a Robinson R22 helicopter can manage, and some 60 mph (97 km/h) quicker than the cruising speed of a Cessna 172, the most common fixed-wing aircraft in production.

Running on lithium nickel cobalt manganese oxide batteries, the range would be around 200 miles (322 km) before you hit the 45-minute reserve mandated by the FAA. Range can be boosted by taking off and landing runway-style instead of VTOL, and since every prop on the plane is connected to an electric motor, there's some possibility of using ambient wind to put some power back into the battery when the aircraft is on the ground.

Joby believes it can produce the S2 for a price around the US$200,000 mark, and due to its fully electric operation, running costs should be a fraction of what a typical helicopter requires.

So what you've got is a two-seater with the convenience of a helicopter, the redundancy, stability and reduced noise of a 12-prop multirotor, the efficiency and low maintenance of an electric, and top speed figures closer to what fixed wings can achieve. A remarkable design that's only possible because of the rise and rise of lithium battery technology and high power electric motors.

It's an extraordinary design, by a true innovator with a well documented knack for starting very successful companies, so we wouldn't be surprised if the Joby Aviation team gets this one off the ground, so to speak. We sure hope so.

Check out some computer animation of the concept in the video below.

Source: Joby Aviation

30-sec TECH: the amazing Joby S2 tilting VTOL multirotor

23 comments
Nik
"Awesome stuff" Also an 'awesome lot of stuff' to maintain, or go wrong.
swaan
With good fly-by-wire software this could be very safe in the sense that it could handle multiple failures without making the aircraft unstable or uncontrollable. I don't see it mechanically more complex as a twin-prop and it's certainly simpler than a helicopter.
Bob
200 mph and 200 mile range is very optimistic and would take quite a high density battery. Nothing was said about service ceiling or payload weight. Even conventional aircraft are greatly affected by air temperature and air density at altitude. VTOL with small props would be affected even more. Folding all those propellers into bullet shaped pods would involve a lot of moving parts which have the potential to fail due to dust, sand, rain, and ice. I have to say that the design is interesting but scaling up from small VTOL drones and making this thing aerodynamically clean enough to fly 200 mph with a useful payload will be very unlikely. Eliminate eight pods and the VTOL capability and this might be a viable electric powered conventional airplane.
grtbluyonder
The path from concept to reality is a long one. Nice dream though. Looks like an awful lot of electric motors and therefore battery power (heavy). Maybe it will be able to carry a pilot but I'd love to see the weight calc math.
vtail55
Fixed wing aircraft and helicopters both 'work'. Transitioning from one to another is apparently a big challenge (V-22). Because of the many motor/prop combinations, perhaps that will be easier with this design. The rotor disk loading is still incredibly high (compared to an R-22) ...and as for the $200K price point...good luck... All that said, I would love to have one...as envisioned..
POOL PUMPREAPAIR guy longwood
The Spruce Duck
StWils
Get back to us when they get one built and airborne, preferably more than a few times, and also once they strap in one of those whole-aircraft-parachutes.
the.other.will
Bob, I appreciate where you're coming from but, as I understand the current state of the art (from a piece about drones), electrically driven rotors scale up linearly. So unlike IC or turbine engines, there's no economies of scale or of cost from using fewer electrically driven rotors of greater power than more of lesser power. However, the 4 cruise props are still dead weight on take-off & landing & the 12 lift rotors are dead weight while cruising. There's no mention of whether or not there can be more cargo or range using short take-off & landing instead of vertical.
WillieNAz
As far as saving energy by taking off like a regular plane, why not be plugged in for vertical takeoff and then dump the plug a couple of hundred feet into the air (heck even have it on a retractable reel)? Needs a lightweight quasiturbine engine with coils inside to generate electricity from gas and that should up the range. I remember years ago there was a plane that was crash proof because of how they oriented the wings to the planes center of gravity. Now if they could bring the props in closer and do more of a bi-plane concept to increase lift with closer in shorter wings and have the wings fold in when it lands you could almost go in a parking space with one.
ozAndy
This actually looks viable. Electric motors are very simple and reliable compared to turbines or IC engines and also lighter and more efficient. The spinning can just has rare earth magnet holders and the coils are stationary so it is just a shaft on bearings. The controllers may be a weak point but multiple redundancy should make the whole unit reliable enough. No flaps or LE extensions needed in the wings which makes wings much simpler. No variable pitch mechanisms in the props, although fold-back props are a little bit more complex they are nowhere near as hard to do as VP. Wingtip props can be used to minimize vortex at cruise speeds like the flying flapjack. This design could also use STOL to save power if VTOL is not needed, and in some situations WillieNAz's idea of a tether may save some juice. The beauty of a true VTOL design is that, with computers doing the flying and ATC you have the potential of efficient point to point flight without airports nor conversion to "car form" for the last few miles of travel (The only viable "flying car" scheme IMHO, forget the "car" bit completely). I suspect batteries, regulators and patents are the major stumbling blocks now.