It’s a jet and a backpack; that can take off vertically. There’s a large suitcase that our whole JB-9 will fit into. It’ll fit in the back of a car. The JB-9 uses a carbon-fiber corset that straps to the pilot’s back, with the majority of the “backpack” section carrying fuel. The device can carry a total of 10 gallons of fuel, which it burns at around a gallon a minute. And the fuel itself is kerosene.

Mounted to each side is a small jet turbine engine that provides upward thrust. These engines mix ambient air with their exhaust gases to bring temperatures down to a comfortably warm airstream. The exhaust temperature actually declines really quickly.

On the left hand is a twistgrip controlling yaw. If I turn the hand to the left, it will spin to the left. There are some little yaw vanes at the bottom of each engine, a little cup that tilts backward and forward. They’re on push/pull cables. They’re always going in the opposite direction to each other, so if you vector the right engine forward, the left one goes backward and you get that yaw rotation.

On the right is a fly by wire throttle driving the engines. That actually works back to front compared to a motorcycle throttle. Going back into the 1960s, the way Bell had it set up, you turn your hand inwards to develop thrust. The JB-9 works the same way.

The twistgrips sit on the end of levers, which can be pushed up and down to tilt the jet engines, either individually or together. Rather than just vectoring the thrust, they vectoring the entire engine on a sort of gimbal arrangement, not only moving the line of the thrust, but moving the centre of thrust.

To go forward or backwards, which requires pitch, effectively its pushing both handles down, that’ll make it go forward. Pulling them up, or actually allowing them to come up, because that’s what they want to do under thrust, will make it go backwards. Or more likely, just slow down from speed. The whole thing is completely manual at the moment, it’s literally a pair of levers tilting the engines.

You don’t need much roll as it’s similar to that. Once you start a roll it will basically follow that. It’s kind of kinesthetic, once you start a roll by shifting your body one way and pushing your arms down a little to the left, it’ll continue that rolling motion to the left.

The JB-9 is limited to the required standards, which is 55 knots, or just over 100 kilometers per hour.

Vertical speed depends more on the fuel payload. There is an initial climb rate of 500-1000 feet a minute and as fuel burns off, you get extraordinary vertical rates. Being turbine engines, they don’t run out of performance as the air thins. They’ll just keep going, they’re compressing the air like a turbocharger.

The total endurance of the JB-9 is 10 minutes plus, depending on pilot weight. It also depends a little bit on temperature, altitude and that kind of thing, but that’s by no means as significant as the total pilot weight.