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Aerovelo's Human-Powered Helicopter Wins $250,000 Sikorsky Prize
First time accepted submitter oritonic1 writes "Since 1980, several teams have tried (and failed) to build a human-powered helicopter that could win the elusive $250,000 Sikorsky prize. But a Canadian start-up, Aerovelo, has finally taken the crown with Atlas, a human-powered craft that managed to stay at least 10 feet in the air, for 60 seconds, within a 30'x30' area."
That guy piloting it: same guy who flew the human powered flapping wing aircraft: https://www.youtube.com/watch?v=0E77j1imdhQ
With the speed those rotors are turning, I don't think there'd be much in the way of ground effects generated.
Just an old helicopter mechanic tho, not an aeronautical engineer So I might be completely wrong..
A bullet may have your name on it, but artillery is addressed to " Whom It May concern"
Human-powered flight is unlikely to ever be a real player (look how hard he has to pedal just to stay 10 feet off the ground for a minute!)
However, the engineering and material science that was used to make this possible could easily translate into lighter helicopters, electric vehicles, drones, you name it.
Just as flying solo across the Atlantic wasn't really something anybody did much after Lindbergh, neither will anybody do much human helicoptering (?) But the fact that it can be done will help humanity long term. Well done!
Great warrior...hrmph! Wars not make one great.
Who cares? It's human powered. It hovered. The thing looks like it's escaped from a Laudanum dream. Give the cyclist a stovepipe hat and a suit and reclaim steampunk from the dorks that think gluing a couple of gears on a USB stick is something to be proud of.
Now go back to plane spotting and leave us alone with this awesome contraption.
That's exactly it. I think they increased the surface area to ridiculous lengths to their advantage. It's not very usable that way, but they did manage to meet the parameters of the contest. I'm not sure this design could ever be shrunk enough to be usable, but maybe as a way to put a small electric motor on a helicopter that you can slow enough not to kill you in a crash landing, this could have merit.
Peter predicted that you would "deliberately forget" creation 2000 years ago...
This could go into guiness records, on more grounds than one. What i dont quite see is how this thing is stabilized, there must be more than steampunk behind the scenes.
Ground effect depends heavily on rotor size, and those rotors are enormous.
well.. isn't what it really depends on the speed of air put down.. I don't think ground effect played that much of a role. it flies by any definition of flying. fyi wright flyer 1 barely broke 10 feet in altitude.
world was created 5 seconds before this post as it is.
I'm sure they built it that huge just for funsies. Surely it didn't occur to them to use smaller rotors, you know, like every single helicopter ever built on Earth. They probably just didn't think of it.
Man, people who do things that have never been done before are so dumb...
Why yes, I AM a rocket scientist!
a stovepipe hat and a suit
That should have been specified in the Sikorsky prize rules
More music, fewer hits
Downward velocity component (affects the trapped/confined pressure differential), altitude of wing (affects confined pressure differential, and the formation of wingtip vortices (and their disuroption) which is part of GE), and wing dimensions/properties (wingspan, chord, airfoil shape, affects downward velocity and the confinement of the differential). and indirectly weight of the aircraft (not because it causes ground effect, but because it determines the effectiveness of it as the force opposing lift)
The guy who said the election was rigged won the presidency with the second-most votes.
So my question is, would it be feasible to generate this same level of thrust in a smaller area using the same amount of power?
No. The amount of thrust goes up linearly with the velocity of the airflow, but the amount of energy required to move that air goes up as the square of the velocity. So for the fixed amount of energy that a human can produce, you will get more thrust by it pushing down a large mass of air at a low velocity than a smaller amount of air at a high velocity.
With the speed those rotors are turning, I don't think there'd be much in the way of ground effects generated.
Just an old helicopter mechanic tho, not an aeronautical engineer So I might be completely wrong..
Typically about 1.5 rotor diameters are where it stops helping a traditional helicopeter. In this case, at 10 feet up with a 30 foot diameter, the slow rotor speed notwithstanding it will make a significant contribution. The air below the rotors can't freely move downward until the momentum of the wind dissipates; this energy creates lift.
Ben Berry from Gamera was actually a previous coworker before he went to work on their HPV project.
Source: Aero engineer, rules of thumb there are from asking around at Sikorsky years ago. Also, I don't like how they say this at all, but it at least says the ground effect is significant:
Three years ago, as Staruk and his UMD team began building their first iteration of Gamera, they quickly encountered the boundaries of current aerodynamic understanding. To rise off the ground, human-powered helicopters are helped by a phenomenon called ground effect, in which wings close to the surface of the earth experience a sharp reduction in drag. It's very helpful in getting off the ground but difficult to model. "Ground effect is a very complex phenomenon; there are all sorts of vortices," Chopra says. "You can only validate experimentally. There isn't much theory."
http://www.popularmechanics.com/technology/aviation/diy-flying/two-teams-one-dream-the-human-powered-helicopter-15354870-2
I forgot to mention the most important part -- the majority of the flight is done very low:
Power required is shown for rotor height of 60 cm (2 ft) above the ground. The 60-second duration flights will be flown as close to the ground as possible to increase ground effect advantages.
http://www.agrc.umd.edu/gamera/gamera2/gamera2-rotor-blades.html
As someone who has started learning about power and cycling - this was a job for an cat 1 / "elite" racer, or at least someone significantly lighter than the guy in the video. I ride pretty regularly but not competitively, and I'm able to do about 300W for a minute. That's piddlesticks in the world of racing, for my weight.
A sprinter would be able to put out massive power (probably 5-7 times what I can do) but sprinters also tend to be heavy. Someone who isn't a sprinter would have less power, but could weigh 50lb less. There are cyclists who specialize in races with climbing, mostly through being light, pacing themselves properly, and having excellent technique.
I'm wondering how much of a warmup he did - in order to do an effort like that, you really do need to be properly warmed up.
Please help metamoderate.
The AHS publication of the Sikorsky prize regulations, Flight Requirements 4.4.3, states that "a reference point on the non-rotating part of the machine will be established as a means whereby the observers can judge that the machine stayed within the confines of the 10-meter square", thereby clearly indicating that one point on the machine must remain within a 10 m x 10 m square, not the entire machine.
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