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:
“Dreamer of dreams, born out of my due time,
Why should I strive to set the crooked straight?
Let it suffice me that my murmuring rhyme
Beats with light wing against the ivory gate,”
—William Morris (1834–1896)
“We have bathed, where none have seen us,
In the lake and in the fountain,
Underneath the charmed statue
Of the timid, bending Venus,”
—Thomas Lovell Beddoes (1803–1849)
“I am advised that there is an unexpended balance of about $45,000 of the fund appropriated for the relief of the sufferers by flood upon the Mississippi River and its tributaries, and I recommend that authority be given to use this fund to meet the most urgent necessities of the poorer people in Oklahoma.”
—Benjamin Harrison (1833–1901)