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The human powered helo will have trouble getting that last bit. Getting some liftoff is easy but once you lose the ground effect then you need much more power. When my toy helicopter's battery is almost dead it still with easily fly along the ground like a hovercraft, no higher. How they are trying for the 10 foot mark in that NPR video is with huge rotors. The effect is based on rotor diameter, and goes to zero at about 1 1/4 rotor diameter. It's really effective and 1/4 rotor diameter so by having a 40' rotor diameter they can get a 20-25% boost in lift up to 10 feet.
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