Wing Bending Relief
In fixed-wing aircraft, fuel is usually carried in the wings. Weight in the wings does not contribute as significantly to the bending moment in the wing as does weight in the fuselage. This is because the lift on the wings and the weight of the fuselage bend the wing tips upwards and the wing roots downwards; but the weight of the wing, including the weight of fuel in the wing, bend the wing tips downwards, providing relief to the bending effect on the wing.
When an airplane is being loaded, the capacity for extra weight in the wing is greater than the capacity for extra weight in the fuselage. Designers of airplanes can optimise the maximum takeoff weight and prevent overloading in the fuselage by specifying a MZFW. This is usually done for large airplanes.
Most small airplanes do not have a MZFW specified among their limitations. For these airplanes, the loading case that must be considered when determining the maximum takeoff weight is the airplane with zero fuel and all disposable load in the fuselage. With zero fuel in the wing the only wing bending relief is due to the weight of the wing.
Read more about this topic: Zero-fuel Weight
Famous quotes containing the words wing, bending and/or relief:
“He is outside of everything, and alien everywhere. He is an aesthetic solitary. His beautiful, light imagination is the wing that on the autumn evening just brushes the dusky window.”
—Henry James (1843–1916)
“And then I ran to get away,
But when I stopped and turned to see,
The tree was bending to the side
And leaning out to look at me.”
—Elizabeth Madox Roberts (1880–1941)
“In Tsegihi,
In the house made of dawn,
In the house made of the evening twilight,
In the house made of the dark cloud, ...
Oh, male divinity!
With your moccasins of dark cloud, come to us.”
—Administration in the State of Ariz, U.S. public relief program (1935-1943)