Abstract: Optimal proportion of the weight of the vehicle and payload is important in design of an aircraft. Wing creates the lift required for flight. Spars are the structural members which run through the wing root at the fuselage to the wing tip. Spars carry the major wing bending loads. During the take-off, the bottom layer of the wing is subjected to tensile force and top layer is to compression. This leads the spars to buckle. Hence the spars must be strong enough to sustain the buckling load. If the thickness of the spar is increased, the efficiency of the aircraft decreases. Several iterations are done by decreasing the thickness of the spar. Static stresses and buckling load factors are found out for these iterations and weight optimization of the spar is achieved.