Half a croissant, on a plate, with a sign in front of it saying '50c'
h a l f b a k e r y
These statements have not been evaluated by the Food and Drug Administration.

idea: add, search, annotate, link, view, overview, recent, by name, random

meta: news, help, about, links, report a problem

account: browse anonymously, or get an account and write.



Multiperson human-powered aircraft

  [vote for,

Human-powered flight is now an established technology.

One exponent has even succeeded in carrying a passenger.

But so far, there seem to be no multi-person-powered examples.

This is odd, because the economies of scale apply equally well to all aircraft.

For example, a three-person craft could have the same frontal cross-section and still wouldn't need to have an airfoil of three times the area; it would need to be bigger, and the fuselage would be somewhat heavier, but it's not a linear relationship. Similarly, the propeller could be almost the same size and mass, even though fed with three times as much power.

Crowd-powered flight; an idea whos time has come.

8th of 7, Apr 13 2017


       "You toss me off this airplane, and you are all going down!"   

       Inspired by recent UAL news story.
popbottle, Apr 13 2017

       This seems like a good idea until we get to the bit where we realise nobody at the conceptual stage had considered game theory.
Ian Tindale, Apr 14 2017

       I wonder how many people will be needed on the first human powered airplane to circumnavigate the globe non- stop.
scad mientist, Apr 15 2017

       Assume that a fit human can pedal at max output for one hour in every eight, with seven hours recovery.   

       So the aircraft has to be capable of carrying 87% "deadweight" in terms of power, representing the resting humans.   

       Many wide-bodied aircraft can carry 320 humans, so could 40 humans provide enough power to lift themselves and the other 280 ?   


       The aircraft will be low speed, perhaps 20 knots; your planet is about 24000 miles around the equator. That's 1200 flight hours, assuming no adverse winds - 50 days. Now, given that the humans are exerting at maximum levels, an allowance of 5 litres of water per person per day is not unreasonable. That's 80,000 litres, or 80 tonnes. Some might be recycled, perhaps using a solar still, but a lot will be lost by respiration and sweating. Water could also be collected by condensation from the atmosphere, but it would have to be an energy-neutral process using ultra-lightweight equipment.   

       So, could 40 humans sustain an airframe, 80 tons of water, and 20 tonnes of other humans, in flight at a steady 20 knots, for two months ?   

       The figures don't look encouraging.
8th of 7, Apr 16 2017

       Yes, but if you scale it up (1000 people, correspondingly large aircraft) it becomes feasible, should anyone wish to fease it.
MaxwellBuchanan, Apr 16 2017

       Is there a first class section on this flight?
RayfordSteele, Apr 20 2017

       Single-seated, pedal-powered planes weigh half-a human or less, in comparison to the average car, which weights about a dozen men, or more. You're not getting THAT much extra economy by adding another seat to a pedal-plane as you would by carpooling.
Cuit_au_Four, Apr 20 2017

       Not sure what your point is.   

       Solo human aircraft - 1.5 x mass of human.   

       But a 2-person aircraft isn't going to be 3 x mass, probably only 2.75, so doubling the available power doesn't double the all-up takeoff weight.   

       There's probably an optimum point, beyond which the extra power is all being used to compensate for increasing drag, becasuse the fuselage and wing area are increasing, altho because of square-cube volumetric relationships the larger fuselage will contribute less to the overall increase in cross-section; but the Law of Diminishing Returns always gets you in the end.   

       The limiting factor is probably related to the strength of materials that make up the airfoil.
8th of 7, Apr 20 2017

       //but the Law of Diminishing Returns always gets you in the end.//   

       Au contraire. The more people, the better the returns. The curve never levels off, at least until you reach the point where parts of the plane are poking out of the atmosphere.
MaxwellBuchanan, Apr 20 2017

       // Assume that a fit human can pedal at max output for one hour in every eight, with seven hours recovery. //   

       I suspect that you can get higher average power from each person if they are working at a greatly reduced level for a higher percentage of the time. I started trying to put some numbers together to defend that assertion, but I got bored...   

       Food and water requirements are a very valid point. The first team to accomplish this will probably need to "cheat" using in-air "refueling".   

       Circumnavigation is a very long term goal. A closer milestone might be something like an 8 hour flight with 3 people that would be completely impossible with only 1.
scad mientist, Apr 22 2017

       // I started trying to put some numbers together to defend that assertion, but I got bored... //   

8th of 7, Apr 22 2017


back: main index

business  computer  culture  fashion  food  halfbakery  home  other  product  public  science  sport  vehicle