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Using graphs in Aeronautical Engineering

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Activity 1:
Go to http://www.grc.nasa.gov/WWW/K-12/airplane/vel.html (external website) and use the simulator to determine the effect of airspeed on lift. When you double the airspeed, what happens to lift.

The velocity used in the lift and drag equations is the relative velocity (external website) between an object and the flow. Since the aerodynamic force depends on the square of the velocity, doubling the velocity will quadruple the lift and drag.

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Activity 2:
Go to http://www.grc.nasa.gov/WWW/K-12/airplane/incline.html (external website) and use the simulator to determine the effect of angle of attack on lift. When you increase the angle of attack, what happens to lift.

Lift increases as the angle of attack increases up to a point when the boundary layer separates from the aircraft and the airfoil stalls.

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Activity 3:
Go to http://www.grc.nasa.gov/WWW/K-12/airplane/factord.html (external website) Briefely state the effect of angle of attack on induced drag. When you increase the angle of attack, what happens to induced drag.

Like lift, drag actually varies with the square of the relative velocity (external website) between the object and the air. The inclination (external website) of the object to the flow also affects the amount of drag generated by a given shaped object.

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Activity 4:
Go to http://www.grc.nasa.gov/WWW/K-12//airplane/atmosi.html (external website) and use the simulator to determine the effect of altitude and combined factors on lift. When you increase the altitude, what happens to lift.

As we increase altitude, the air becomes less dense and the lift decreases for a given airspeed and angle of attack.

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Activity 5:
What happens during take off and landing that would change the flight characteristics of the aircraft such that different maximum speeds would be specified?

Landing gear lowered and flaps deployed to augment lift.

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Activity 6:
Why does the minimum air speed increase from 300 to 310KEAS?

The aircraft reaches Mach 1, shock induced drag adds to sum total of drag, and the minimum KEAS is increased.

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Activity 7:
The pilot is flying the aircraft at 73,000 feet and wishes to bank the aircraft to turn. He is traveling at the maximum airspeed. What must he do before turning.

The pilot must reduce power to slow the aircraft to a speed allowing the bank of up to 35°.

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Activity 8:
During subsonic flight what is the maximum angle of attack below 25,000 feet?

14°.

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