in this video we are going to look at the engineering of two seater version of the Opener's BlackFly and how a fuel cell can increase its flight time by more than 5 times.
It might be interesting to look at a fuel cell Velocity kitplane. It comes in several variations, single engine and twin engine. Not VTOL but they are roomy with doors and cruise pretty fast and have the stall resistant canard design.
Thank you for this excellent analysis. I would suspect the formal certification for a version with hydrogen fuel cells would be particular about the potential safety of the system in a crash. How might this be compared to the certification that the Toyota Murai had to have to ensure motorway safety?
As long as hydrogen is allowed to vent externally its fine. Any leakage form the cylinder should not come into the cockpit. So an external chamber will be required for hydrogen tanks
Adding 110 Kg of LiPo will do almost the same trick at the half the cost and no additional complications of hydrogen and no hydrogen refiling needed as added cost per mile. Also a U shape redesign of the wings will add lift surface without extra length of the wings keeping it all nice and tidy. My point is if we redesign the FAA requirement for electric powered ultralights around 300-400 kg this can still be made. Law should keep up with innovation not the other way around.
Until battery storage capacity per weight gets much better it seems hydrogen may be the way to go for e-VTOL aviation. While you are scaling that up it might be worth looking at a three seat version where one can have one person and some cargo plus the fuel cell or two person with no cargo and the fuel cell or three people with limited range or one person and two fuel cells with maximum range.
I don't know, if you imagine living off grid and commuting to the nearest city for work or shopping, the blackfly is already fine. Ignoring regulations, the international version has 12 kWh and 40 miles / 64.4 km. That is more than enough to commute. And small battery means quick recharging from a normal outlet or directly from solar panels. Energy efficiency is better than a big electric car and embodied energy is probably less too. If you would re-engineer how our society operates you could replace almost all medium range personal transport. This plus bicycles and trains. Most roads would no longer be needed.
This was really cool! I would love to hear more estimates like this for other possible aircraft. It would be neat to see your math and assumptions made written down as well. Either as part of the video or separately. Awesome work!
Noted! All the videos where I have presented the underlying maths and assumptions get people really bored. You can see them on the channel. People quickly switch it off. This really hurts my channel ranking and my future videos are also effected. The only thing I can do is create a separate channel for the maths and make a community of like minded people.
@@ElectricAviation Fair. I follow a lot of fun math or intuitive math channels and it can be made entertaining! I thought this one made the maths not too boring because of the creative thinking involved with it. Imagining how craft could be and using the maths to show how!:)
I'm curious about the prospect of replacing the battery altogether with a supercapacitor, and what would happen to the weight and performance in that case. Also, I'd like to see what could happen with a new rotary engine like the Liquid Piston driving a generator instead of a fuel cell. I'm sure it could be far cheaper than $40K for the fuel cell.
What about using a gas-turbine generator running on biodiesel? Its exhaust could be vectored rearward to produce some thrust as well. Surely the power to weight ratio is much better than a fuel cell? (plus producing and compressing H2 is so horrendously inefficient)
So if you take the weight of the tanks into account the energy density of 120MJ/kg for hydrogen drops to 6.5MJ/kg, if I'm correct. Could you maybe do a video on comparing alternative fuels, if their storage + maybe their method of energy generation is taken into account? So like comparing Hydrogen, Ammonia, Methane, Propane, Butane, Ethanol, Methanol, Gasoline, Diesel etc. all while taking tank weight into account, run by fuel cell, combustion engines etc. Maybe also compared to batteries. Maybe also for different sizes of vehicles into account, like ultra light, utility, business jet, airliner.
Wow, I hadn't realized that the fuel cells had that good of a power to weight ratio. That seems like a much more likely way forward for electric aviation, at least for the time being.
Yes, but how easy is it to recharge a fuel cell when you live in a remote location miles from any kind of infrastructure? You can't just plug it in to the mains electricity and recharge overnight, right? My closest town is 6 miles away over rough terrain. I need something that will get me to town and back once per week. I have access to gasoline, electricity and bottled gas. But where am i gonna get Hydrogen from?
Considering the Mirai has been available since 2015 but there are less than 20k sold I am not sure economies of scale will help much. I wonder if you could increase the blackfly range by increasing the prop size.
@@ElectricAviation It would certainly change the noise signature towards a lower pitch, but I would rather listen to a single full-size helicopter than a cloud of drones with the equivalent thrust.
As mentioned in the video, it wont remain part 103. They will have to go for several year long certification process for it to be legal if the weight is increased. This costs a lot of money
VTOL will still always require an airport. You won’t be landing in your back garden unless you live in a the boonies and have a lot of land. Helicopters been out since the 50s and nobody is landing them in their garden.
VTOL will still always require a pin airport. You won’t be landing in your back garden unless you live in a the boonies and have a lot of land. Helicopters been out since the 50s and nobody is landing them in their garden.
I'm a great believer in fuel-cell power, but for this aircraft there are two problems that I see ... 1. Storage of hydrogen in the aircraft. Unless new technology comes up, it will mean that the tanks will have store the gas at ENORMOUS pressures. 2. That said, where will one get the hydrogen from? And how to refuel the aircraft? Currently airfields have no storage facilities for the gas and building one will be hugely expensive, forgetting for one moment, all the certification of the storage facilities - which will be essential. As we all know, hydrogen is highly inflammable, so the certifying authorities will be pushing hard to ensure that there will be no leaks.
Oh, and we desperately need to improve our government's focus onto real issues instead of contrived useless, childish manufactured conflict for any of this to be possible in the first place.
I don't understand why all the videos, it's been going on for over 5 years !! You get everyone excited about getting one !!! But you can't buy one that's really crazy.
I always enjoy your videos. I'm surprised that airspeed and range are not mentioned. The biggest problem I see with the "Black Fly" is it's name. It would be difficult to find a worse name. Thinking about it for a moment I actually came up with a couple I will not share. Here are some I think would be better - Black Thunder, Black Lightning, Black Dove, Black Hawk. Perhaps next time you visit the Black Fly you could provide wing loading, cruise speed, range especially if you are looking at variations . I guess knowing the ceiling isn't that important. Just thought about possible emergencies and the on that jumps out is electrical fire. It doesn't have any provisions for an event like that. I think flight safety would be a good topic for a future video.Please keep up the good work.
A military version of it with the name Black Thunder would be very apt. The good thing about the black fly is that the batteries arent in the cockpit. they are in the wings, behind the propellers. Lining of a fire retardant material would protect the pilot. The cruise speed is 80 mph. I wanted to give more numbers but feel people in general dont care much other than flight time.
@@ElectricAviation That's pretty fast. Having the batteries in the wing isn't all that great. In the event of a battery fire the wing would fail quite rapidly.
@@LosZonga Another problem with the batteries in the wing is dumb bell effect. Possibly the battery could be 4 parallel parts with temperature monitoring so in the event one would would catch fire it would automatically be ejected but attached to a cable so it didn't fall onto a house or person.
The only way to get personal flight to the market is at least devolep systems who can contain a minimum of 4 persons, like the family salon car. There is the biggest full market potentional. And a low noise reducal because mostly you have to deal with saburban aereas.
you can do all the components yourself with ease, especially the metal-air aluminium-spiral anode fuel cell with standard carbon air-electrode, ethanol-koh electrolyte will limit metal passive corrosion, ie, non-active losses
flywheel, flat disc, r=1m, f=3333Hz (200krpm) has energy density of 30kWh/kg, design equation S=E/m=(pi^2)*(r^2)*(f^2), r=flywheel disc radius, pi = 3.14159, f=revolutions per second, should be floating on vertical maglev bearing stick, its the easiest, gives gyro stabilization at same time, try contra rotating twin flywheel battery, same or better, adjustable, than plain hydrogen, jet engines have revolution speeds of 200krpm, its already been done, but use that in the flywheel energy storage, and yes, electric motor-generator combo, assume 100% efficiency, for real
by merging of blackfly,Jetson one and orb features some better design can come out . alone something somwhre thre will be some drawbacks.so merge for the benefits of mankind come out flying car dream true . blackfly takeoff characteristics, Jetson one compactness and orb wing design are excellent.
