
Would have a higher maximum payload than a similar design with normal wings.
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Fri 15 May 2009, 14:02,
archived)

The aerofoil lift effect on the wings would no longer be straight up but rather at an angle to the fuselage, creating a torsional strain on their fixtures. The wings would have to be parallel and straight out to gain maximum lift. Even then there'd be more drag. So 4 wings = more lift, slower stall velocity, more drag, more fuel consumption, lower maximum velocity.
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Fri 15 May 2009, 14:30,
archived)