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In: Mechanical Engineering

A model aircraft in a wind tunnel with a wing area of 0.9 square meters and...

A model aircraft in a wind tunnel with a wing area of 0.9 square meters and a chord of .24 meters is subject to a sea level standard airflow at 130 m/sec. The zero-lift moment about the center-of-gravity is measured as – 7.8 N m. At a different angle of attack, the moment about the center-of-gravity is measured as 13.5 N m with a lift of 2,650 N.

(A)Calculate the value of the moment coefficient about the aerodynamic center, and the location of the aerodynamic center (relative to the cg).

(B) Lead is added to the tail so that the center-of-gravity is shifted aft by 25% of the chord. Calculate the moment about the center-of-gravity with a lift of 3,000N.

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samet mamat answered 2 years ago
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