Concept explainers
A small aircraft has a wing area of 35
(a)
The takeoff speed.
Answer to Problem 85P
The takeoff speed is
Explanation of Solution
Given information:
The area of aircraft is
Concept used:
Write the expression for the lift force.
Here, the density of water is
Since the weight of airplane should be equal to the lift force for takeoff of airplane.
Write the expression for the weight of airplane.
Here, the mass of airplane is
Substitute
Write the expression for the drag force.
Here, the discharge coefficient is
Write the expression for frontal area of flow.
Here, the length of pipe is
Substitute
Calculations:
Substitute
Conclusion:
The takeoff speed is
(b)
The wing loading.
Answer to Problem 85P
The wing loading is
Explanation of Solution
Given information:
The area of aircraft is
Concept used:
Since the weight of airplane should be equal to the lift force for takeoff of airplane.
Write the expression for the weight of airplane.
Here, the mass of airplane is
Substitute
Write the expression for the load on wings.
Substitute
Calculations:
Substitute
Conclusion:
The wing loading is
(c)
The power required.
Answer to Problem 85P
The power required is
Explanation of Solution
Given information:
The area of aircraft is
Concept used:
Write the expression for power required.
Write the expression for the drag force.
Here, the discharge coefficient is
Calculations:
Substitute
Substitute
Conclusion:
The power required is
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Chapter 11 Solutions
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