Move over Chitty, Chitty, Bang, Bang there’s a new pie in the sky…Is the fuel cell the thing to spark the EV market?
So go some of the lyrics of the song dedicated to that mythical flying car Chitty, Chitty, Bang Bang. Now, the science fiction idea that has thrilled theatre audiences and picture goers for decades has leapt of the stage and silver screen to really take wings. And it’s all down to a convergence of technology developments, such as lithium batteries, multirotor drones, electric aircraft, cheap and plentiful inertial sensors and the pioneer spirit of organisations such as a small company based in California.
Standby: a transport revolution is about to take off and according to NewAtlas, one of unexpected new contenders is Jetpack Aviation, run by personal flight pioneers David Mayman and Nelson Tyler. The JPA team has made stunning progress in the last few years by developing the world’s first jet turbine backpack, a wild sci-fi dream come true.
Mayman, as CEO and chief pilot, has been staging spectacular public flights of the JB-9 and JB-10 jetpacks all around the United States and Europe and the company recently announced that if you’ve got the cash, you can actually buy one right now. With a six-turbine JB-11 jetpack about to be built, some US Army contracts for an all-electric JB-12 in development, the JPA team certainly has its hands full. But not too full to begin pressing ahead on a wild manned multicopter flying car concept that’s yet to be named.
Currently at the CAD render stage, the JPA VTOL concept is an early vision of a three-dimensional single-seat commuter. It’s a manned multirotor, with 12 props mounted coaxially on six arms. For all intents and purposes, it’s a single-seat electric multicopter that’ll fit in a single car garage thanks to the center arms folding in. The ‘Chitty, Chitty, Bang Bang’ race to build the first commercially-viable flying car is certainly on NewAtlas put some searching questions to David Mayman aimed at flushing out what he thinks about it all:
Larry Page has two separate bets on the table, with Zee.Aero and Kitty Hawk. Airbus is having a go with the Vahana. You’ve got eHang in China and e-Volo in Germany making manned multicopters. Dezso Molnar‘s doing his thing with the Street Wing and the Gyrocycles – he’s an amazing individual, although from my discussions with him, it seems he’s not interested in anything that’s not roadable.
Our chief engineer Stefano went up to northern California and actually managed to get out on a full tour of the Joby Aviation facility and he said what they’re doing out there with the S4 is amazing. There’s two schools of thought. You’ve got your winged aircraft with distributed electric propulsion-the Joby, the Airbus, the Zee.Aero– the advantage here is high speed. They can cruise at 320-480km/h), so you get speed and range out of that.
We’re on the other side. We’re taking the manned multirotor approach. More than anything else, because some of the technology’s already proven enough. The speeds are lower. You might be talking about 145km/h, but the size factor is so much smaller because you don’t have a wing to deal with.
The way we’re designing ours, there are actually six arms that come out from the top of the chassis, two at the front, two in the middle and two at the rear. The middle one can fold in. The design direction I’ve given is that it’s gotta fit inside a single car garage. It’ll be low enough and thin enough to do that, because the side arms and motor pods fold in against the chassis.
There’s only one seat in it at the moment, but the beauty of distributed electric propulsion is that it’s very, very scalable. The way that electric motors work, it’s hey, you wanna make something for two people? OK, you just add power to the electric motors. The ultimate limiting factor comes from battery storage density.
We all, Tesla, everybody working in this space, need it to be higher than the current 200-odd watt-hours per kilogram we can get at the moment. But they’re talking about in four years, maybe it hits 400w. That’s huge, that’s where these electric aircraft will all become very realistic. We started with landing skids, but we’ve ended up with little spheres or landing balls.
The Volocopter is a much bigger concept, using the same German Hacker brushless dc motors we’re looking at. They’re using 18 rotors, I think, which are spread out on six arms that split into 12 arms, and it’s quite a large footprint. But they’re not mounting the motors coaxially like we’re planning to with coaxially mounted double props on each arm.
Our concept is that on the end of each of our six arms, you’ve got a motor on top and a motor underneath. They spin in opposite directions. It does come with inefficiencies, because the air that’s being pushed from the top one down has already been accelerated. So the pitch angle on the lower blades has to be different. But it leads to a much smaller form factor. You can see how instead of having to find real estate for 12 rotors all mounted so the props don’t hit each other, this way we can use half the space.
We’re still doing the math on the coaxial design in terms of efficiency. We know it works, I mean there’s DJI drones out there using it right now. But we just don’t know exactly how much efficiency we lose by running it that way.
At this stage we’re going for custom wooden props instead of carbon props. You can get them incredibly light, and they’re much more resistant to damage. With a carbon prop, if you get any damage, like a little stone, or something, they’re pretty much stuffed. A wooden prop is very easy to repair, and there are fantastic little prop makers who can make them any size you want, so they’re not very expensive.
These things operate relatively close to the ground, you’re talking about two meters off the ground. There’s always the risk of them picking up stuff. I mean, if you look at the eHang 184 out of China, their lower props are literally, they look like eight inches off the ground. I don’t see how that’s going to work. If you land on ground that’s not perfectly level, or if you come it at a bit of an angle, the prop’s the first thing that’s gonna hit the ground. I’m not quite sure what the thinking was there. But they have raised a lot of money, I’ve heard somewhere around US$80 million. So our props come off the top. Obviously that means some added weight, because you have to have that extra strength through the whole airframe structure to carry the load from the top rather than the bottom.
What can you do to extend flight times while battery tech catches up?
We’re looking at designing something similar to an extended-range electric car, with a generator on board. In fact, we were looking at perhaps building in a turbine motor, thanks to our experience with turbines on the jetpacks. A very small one, a tiny one, the size of a coke can, can produce a lot of power as a generator. They do consume fuel faster than, say, a two-stroke motor, but they’re so much lighter that you can carry more fuel. Anyway, it’s one of the concepts we’re looking at. And it could take something from a 20-minute flight time up to an hour with a hybrid range extender.
What’s the end game with this design?
I don’t want to sound overly optimistic or sci-fi, but these things will be practical. Once the battery density technology advances, these things will be a practical form of transport. We know the infrastructure has to catch up. We know the regulations have to catch up. But I think that the Uber Elevate whitepaper is right on the money. We all know that this stuff is gonna take time, but at the moment, as we’re talking, I’m sitting on the 405 in LA… We’re working as if it’s a two dimensional world, traveling in serial, car after car after car. All this airspace above us is completely unutilized between 100 and 1000 feet.
One day, that space will be used. We’ve got plans on being a part of that. We know it’s not gonna be the gas turbine engine that makes sense for that. We know it’ll be electric. The technology with battery storage capacity will catch up, and it’ll take time. But in the meantime, we work on the other stuff: the airframe; the motor systems, the stabilization.
Drone technology has advanced all of that stuff, the autopilot, the stabilization, to the point where we nearly don’t have to do any R&D for that. We can just about start from off-the-shelf products and customize them for our use. And, of course, mobile phones have generated such a leap in accelerometers and sensors. The power you’re carrying around now in terms of inertial measurement and GPS, used to cost a hundred thousand dollars. Now an iPhone’s got three, and they probably cost 20 cents each. And that’s driven drone technology.
Then there’s the software. Honestly, we could probably build this thing initially using standard hobby-grade DJI software and it’d work, and it’d probably be pretty much bulletproof, the way they make these things these days. It’s just that we want to have redundancy, and we want to be really, really sure that if some circuit board fries, it’s got a backup. That’s where the engineering effort becomes pretty serious.
But just 15 years ago, it would have been an incredibly daunting undertaking. You would’ve had to go to Lockheed Martin or Northrop Grumman for every component. Now you could probably build a whole prototype for a million bucks.
Of course, people are doing it a lot cheaper. I’ve seen some of the videos. For 10 grand you could get something together if you were crazy enough to fly the thing. But if you want to make something that’s a little more mil-spec in terms of reliability and redundancy and what have you, and you want to do the carbon fiber work properly, and the engineering studies, it’s a more expensive exercise.
What’s the timeframe on getting a prototype built?
Our head engineer Stefano, he gets to work on this as his third priority after the electric six-fan jetpack (the JB12) and the six-turbine jetpack (JB-11). Poor bugger! The JB-11 should be finished by the end of February.
The electric fan jetpack is next. And it won’t just be a training rig, it should be able to fly under battery power for about five minutes. It’s going to be a pretty awesome machine. You get the redundancy benefit from multiple fans, we get to play with stabilization systems because it’s electric and that’s really easy, and it’s a lot quieter, and frankly it’s part of the deal we’ve got with the US military guys.
For a company of four people the pace is insane but we’re getting an amazing amount done. These VTOL renders are pretty accurate, we believe. We know where we can get the motors, we know where we can get the props, we know where we can get the control systems… We just haven’t started building it yet. I think maybe six months is a reasonable estimate on when we’ll start. To some extent it’s a bit cash flow dependent, but assuming all goes well it’ll be in that sort of time frame.
And it shouldn’t actually be a long build. The carbon fiber work is a known entity. The accelerometers and the autopilot, that sort of thing, we know exactly which systems we want to use. The build time on a prototype shouldn’t be that long.
How can you ensure pilot safety?
In terms of redundancy, with the VTOL, we’ve got 12 props. And while it does depend on which side you get the failures on, we’re working on the basis that you could lose half your motors and still come down at an acceptable descent rate. Then it goes to the undercarriage system, something that can collapse in a certain way.
Most of these will probably have a ballistic parachute, but parachutes are only effective above a certain height, which depends on your horizontal velocity and height. If you’re in a hover, then with the fastest stuff any of the companies we’re talking to can build-Parazero and what have you- it’d only be effective if you’re above 50 or 60 feet, which is actually really low. They can bring you down safely from that kind of height.
There’s a bunch of companies working on a solution to get a canopy out for when you’re moving slowly and you get an immediate stable descent. They might punch it out with an airbag, or drag it out with a tractor rocket. They might fire out weights, like lead balls, that open the canopy out immediately. The problem with all of that stuff is that it works really well when you’re in a slow, stable flight, or a hover. As in, it works in ideal conditions. But if you’re flying along at 129km/h and you have a massive asymmetric thrust event, and you start toppling, then it doesn’t work so well. Then you’ve got a canopy that’s firing while you might be upside down. You might open the chute too fast and it rips it to bits.
There’s a lot of people struggling with it. So what’s the ultimate rescue system for a manned VTOL aircraft? Something that works slowly enough to be effective at 322km/h and yet can fire out quickly enough to be effective in a stable drop from about 15m. It’s really interesting stuff.
What about below 50 feet? That’s still a deadly fall.
Then you’ve got the whole concept of airbags. We’re actually working with Takata, the big automotive airbag company. They’ve got an aviation division out in Florida, so it’s a question of filling in the safety gap below 50-60 feet. If you drop from, say, 4.5 m, how do you immediately get an airbag out to cushion that fall?
With the jetpacks, we’re looking at a system that actually jettisons the aircraft from the pilot’s corset with explosive bolts and then protects the pilot with an airbag, something like a giant Zorb ball. You can think of it a bit like the hedgehog thing they had in the Tomorrowland movie. But the challenge is you have to generate a huge literage of gas in a very short time to be able to fill it.
But with the jetpack jettisoned, you’re dealing with about 100kg (220 lb) instead of, say, 160 (353 lb). Of course, the first thing the FAA says is well, what happens to the jetpack? Does that just fall out of the sky on somebody’s head and blow up? So then you need a little drogue ‘chute for that. That’s not hard to do, we’ve got a lanyard that pulls a pin when the pilot separates, and then the drogue ‘chute can bring that down at an acceptable descent rate. But with every one of these things, weight is the enemy. We’ll have some more power with JB-11, so we’ll have more payload capacity. It’s all there, it’s just time and money.
Is the fuel cell the thing to spark the EV market?
A breakthrough in the ‘electric’ vehicle market could be on the horizon with the announcement that nanoFlowcell is all set to present what it calls the state-of-the-art in fuel cell research at this year’s Geneva International Motor Show (7-19 March). In the shape of the Quant 48Volt, the vehicle is said to feature nanoFlowcell’s low-voltage drive, the world’s first variably controllable mobile flow cell and some ‘all-new’, low-voltage, electric motors, claimed to provide propulsion of racecar proportions.
Late last year the company announced that it had successfully achieved variable controllability for flow cells and that extensive testing of the Quantino 48Volt had confirmed that the redesigned nanoFlowcell system architecture for electric vehicles is suitable for series production.
By being able to directly vary fuel cell control the new system no longer requires expensive and relatively heavy supercapacitors. The company says that it has also made important progress in flow cell research, enabling a significant reduction in the cost and weight of drive systems for electric cars.
According to the nanoFlowcel’s chief technology officer Nunzio La Vecchia, the benefits of the flow-cell based drive technology, compared with other electric drive systems with lithium-ion batteries or hydrogen fuel cells, are remarkable, particularly in respect of power, range, environmental compatibility, cost-effectiveness and safety.
“The average range of current electric cars stands around the low three-digit mark, with most far from able to sustain motorway speeds for extended periods. Moreover, no vehicle manufacturer is currently making money with electric vehicles that are too expensive to produce and sales incentives too high.
A big call, however, he went on: “With the Quantino, we want to show that electric mobility can be different offering not only the range and speed of a regular car, but that our flow cell vehicle is also more economical and environmentally friendly than any other electric vehicle on the market.”
Nunzio also says that electric vehicles, driven by nanoFlowcell, are not only safe, environmentally compatible and efficient to run, they will also be considerably more cost-effective to produce in future than comparable electric vehicles with a lithium-ion battery or hydrogen fuel cell. “For widespread implementation of electric mobility, these are important technological and economic prerequisites that have so far not be met by any electric vehicle concepts currently on the market.”
This AWD electric powerhouse calls on 760hp (4x140kW) to zoom from 0-100km/h 2.4 seconds on the way to a top speed of 300km/h (limited). The stated range is 1000 kilometres, but as with all ‘electric’ vehicles, a pinch of salt may have to be added to achieve such targets. As to the price? Well, at this stage, it’s still only a not-for-sale prototype, but after Geneva perhaps nanoFlowcell will be able to announce a ‘production’ agreement with one of the many OMs it is said to have been negotiating with over the past few years.