“Japanese Student Takes Flight of Fancy, Creates Flying Bicycle” [https://www.youtube.com/watch?v=ZJrJE0r4NkU](https://www.youtube.com/watch?v=ZJrJE0r4NkU)
*Edit: Far beyond regulations and air traffic control issues, only regarding to physics:*
I’ve just seen this video of a Japanese student that has achieved making a flight of about 200 or 300m with a mechanism that turns the pedalling we normally do in a bicycle to the turning of a propeller.
Now, if we as humans and a very great bike can reach 40-50 mph (and very light planes such as cessna can take of with only 60mph – not to mention Bush Planes – all of these weighting easely 4 to 5 times the weight of a person + an extra light airplane design, specifically created for that porpouse) – why does this seems too hard to achieve/sustain? I can only guess its a matter of efficiency (or the lack of it), but which one of them?
In: Physics
If you want a machine to fly, you have to “push” air downward fast enough to not only cancel out gravity, but additionally move you upwards. There’s a LOT of factors to this, but basically there’s not many mechanical devices efficient enough to convert the kind of “pushing” that we’re good at into that kind of force. Also, we can’t “push” that much for very long periods of time.
The main issue with flying bicycles / cars is that by flying, you are adding another dimension to navigation and traffic and safety considerations. How do you keep flying bicycles / cars from colliding in the air? What kind of air routes would need to be set up to keep air traffic from interfering with each other as well as airplanes and helicopters? Pilots get hundreds of hours of training and practice before they can fly. Who would do that just to fly a bicycle? 1 or two flying bikes is a novelty and does not need a lot of regulation, but imagine tens of thousands flying around. It would be a disaster.
I mean you see how much wingspan this thing needs to get airborne, it’s extremely inconvenient and not at all useful (doesn’t go particularly fast, can’t really turn, probably breaks easily if you have any obstacles at all, doesn’t work in bad weather, etc.)
The weight of a human. It would take a very light and physically fit human to operate one for any length of time.
Thats also not considering maneuvering and landing one it an urban environment or the space to store one.
Fundamentally, if you are a 150lb human, in order to fly you need to generate 150lbs of constant downward force. Propellers and wings and whatever else might help with that, but it doesn’t change the basic equation. Lifting your body off the ground is physically the same as lifting 150lbs once a second, every second, for as long as you want to stay in the air.
Nothing. Knew a guy who built one. It takes a very strong cyclist and it’s basically very dangerous and difficult. Need a massive lightweight wing. It’s unwieldy.
You also need to be very strong just to get it 3’ in the air. Like full on sprint for a minute seated on a recumbent
FYI the [Gossamer Albatross](https://en.wikipedia.org/wiki/MacCready_Gossamer_Albatross) was a human powered aircraft that flew across the English Channel 45 years ago.
A fit recreational cyclist can maintain 200W power output while cycling. To pick an example aircraft, a Pegasus Quantum ultralight aircraft weights 400kg fully fueled and its engine outputs 60,000W.
That’s 300x more.
The difference in power output between even the smallest aircraft and a human is absolutely enormous.
Edit: as another comparison, the very first successful heavier than air craft, the Wright Flyer, had a maximum takeoff weight of 338kg and the engine had a power output of 8,900W, and that was only just enough to get it in the air.
What stops us from having flying *anything* in the ~~personal transportation~~ bicycle/car sector is air traffic control. 2D traffic control is already a pain in the neck. You’ve got speed limits, traffic lights, different kinds of road lines, different kinds of intersections, rules for when police are coming toward you or behind you, etc. etc. Naturally, you can’t drive through trees or walls, or drive off-road without destroying your car, so there’s a bunch of natural laws supplementing the municipal ones.
But once you go 3D, all that goes out the window. Now you’ll have to govern how high you can fly, what zones you can fly over (if any), what speeds you can fly at (if they’re different from road speeds), noise restrictions, how you’re supposed to respond to police vehicles, how police vehicles are supposed to respond to you, how to handle cross-traffic and intersections, ON TOP OF the existing land-based rules, which might have to be completely rewritten now that they can take to the skies.
It’s certainly *physically* possible for us to have flying bicycles and cars, absolutely. We’re *long* past the point when we were physically able to make them sustainably. We probably could’ve done it some 30-50 years ago, tbh. It’s mostly the air traffic control problems that are holding it up. If the problem of self-driving cars gets solved, I can see an air-traffic-control solution not far down the road, because controlling the human element is probably the biggest factor here.
That’s my two cents.
In addition to what other people said, they took an extremely aerodynamic position (akin to a recumbent bike) that is much more aerodynamic than the traditional bike. In fact, mediocre level recumbent pro bikers can beat traditional top pros on a flat surface because of this and was a reason why the bike form was denied entry into traditional racing about 100 years ago.
Point being, just to get this thing to fly everything had to be outmaxxed just like that from the humongous wingspan, to the riding angle, to the materials, and mostly likely a fit and trained individual just to achieve this and he certainly didn’t do it for much longer.
Just look up human powered flight. They had copters (quad or heli, I don’t remember), different planes, etcetera but it always had these wingspan, materials, and aerodynamics in one way or another built in.
Personally, I think if a personal flying vehicle ever really gets built on a big commercial scale (not human powered), barring an anti-gravity discovery, it would probably be some type of gyrocopter / autogyro type thing (with AI flying it).
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