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:
“Sure smokers have made personal choices. And they pay for those choices every day, whether sitting through an airline flight dying for a smoke, or dying for a smoke in the oncology wing of a hospital. The tobacco companies have not paid nearly enough for the killing.”
—Anna Quindlen (b. 1952)
“Sometimes we sailed as gently and steadily as the clouds overhead, watching the receding shores and the motions of our sail; the play of its pulse so like our own lives, so thin and yet so full of life, so noiseless when it labored hardest, so noisy and impatient when least effective; now bending to some generous impulse of the breeze, and then fluttering and flapping with a kind of human suspense.”
—Henry David Thoreau (18171862)
“What Congress and the popular sentiment approve is rarely defeated by reason of constitutional objections. I trust the measure will turn out well. It is a great relief to me. Defeat in this way, after a full and public hearing before this [Electoral] Commission, is not mortifying in any degree, and success will be in all respects more satisfactory.”
—Rutherford Birchard Hayes (18221893)