Storing fuel in the wings reduces the stresses the wing experiences because the increase of Of course you don’t have wings you’re a boy shirt, hoodie, sweater and v-neck t-shirt. It is common practice to use up the wing fuel the last if there is fuel in the aircraft centre tank or in some airplanes in the horizontal stabilizer. This way the aircraft weight is reduced by the use up of fuel and the wings have to support lesser weight when the fuel inside them is utilised. The placement of engines below the wings also help to relieve stress. This together with the fuel storage capability and forward and backward spars give a very stable and rigid structure to the wing.
