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## Homework Statement

For monoplane of Clark Y wing, 36-feet by 6-feet, with 3.8 sq ft. equivalent flat plate area, what should be the airspeed for minimum Horsepower when fuel has been burned so that the total weight is 1800 lb?

## Homework Equations

Wing Area = 36 x 6 = 216

Weight = Lift

Weight = Max. Coefficient of lift × (density at sea level/2) × wing area × (Minimum Airspeed)^2

○ Gasoline consumption

HPreq/V = W/375 × (((Coefficient of Drag) + (1.28Ae/ wing area))/Coeffcient of Lift)

## The Attempt at a Solution

Given:

Clark Y wing

Wing span = 36; wing chord = 6

Wing area = 216

Ae = 3.8 sq. ft

W = 1800 lbs

Reqd: Airspeed

Solution:

From the formula

W = Max. Coefficient of Lift × (density at sslc/2) × (Wing area) × (Minimum Airspeed)^2

Since, the problem stated that the wing is Clark Wing, Max. Coefficient of Lift of the airfoil selection is 1.56.

By substituting the given data,

Minimum Airspeed = 67.03 ft/s

My question is, does my answer correct? What is the relevant of the equivalent flat plate area on the problem?

Thank you..