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Posted By: Mike Kremer Human Powered Helicopter - 06/23/12 12:59 AM

This is a Human, using his muscle power only trying to hover above ground in order to win a prize.

He got off the ground the other day with a 35 second hover.
And will make another attempt today (Saterday 23 June)

Dont expect to see a conventional type of spars and plastic film construction.....This Helicopter is very very big.
With the poor guy sitting in the middle of four rotors which he is trying to rotate by pedalling.

I would suggest that it is rather more difficult to stay aloft
the higher the copter rises, since one loses the small benefit
of the air being held compressed between the hangar floor and the underside of the rotors.

Its certainly a great piece of lightweight engineering.
You can catch their attempt live today at:-

http://www.agrc.umd.edu/gamera/index.html

Its difficullt to spot the guy pedalling, since I suspect
others are preventing the copter from any lateral movement?
Posted By: Orac Re: Human Powered Helicopter - 06/26/12 03:18 AM
Originally Posted By: Mike Kremer

I would suggest that it is rather more difficult to stay aloft
the higher the copter rises, since one loses the small benefit
of the air being held compressed between the hangar floor and the underside of the rotors.


It is not designed to hover any higher than what you see in clip as it is using ground effect which is the air compression you talk about above.

So it's more like a hover craft than a helicopter.
Posted By: Mike Kremer Re: Human Powered Helicopter - 06/26/12 04:21 PM
Originally Posted By: Orac
Originally Posted By: Mike Kremer

I would suggest that it is rather more difficult to stay aloft
the higher the copter rises, since one loses the small benefit
of the air being held compressed between the hangar floor and the underside of the rotors.


It is not designed to hover any higher than what you see in clip as it is using ground effect which is the air compression you talk about above.

So it's more like a hover craft than a helicopter.


Originally Posted By: Mike Kremer


Mike Kremers reply to Orac

Oh, I didn't realise that. I expected more height, like 6ft?
I will call it a 'Hovercopter' from now on. Thanks.

Posted By: Orac Re: Human Powered Helicopter - 06/27/12 03:33 AM
It's not your fault for the confusion I argued this with version 1 that they were really exploting a loophole in the sikorsky prize.

The webapage itself declares it to be helicopter (http://www.agrc.umd.edu/gamera/index.html) => "Welcome to the Gamera Human-Powered Helicopter Project"

Yet a quick look at the technical spec (http://www.agrc.umd.edu/gamera/gamera2/M-GameraII-2012-Handout-Rev3.pdf) => "The four-rotor Gamera I configuration, retained in Gamera II, increases vehicle stability while positioning the rotors as close to the ground as possible. This allows an increase in a phenomenon known as ground effect, a “free” increase in lift experienced by wings and rotor blades operating near the ground."

I am not sure that this is what sikorsky had in mind when they set the challenge and I am curious if they do it whether sikorsky will pay up.
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