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3. An aircraft similar to the Hawker Aircraft has a single rectangular spar that runs the entire wingspan. Maximum gross weight, GW = 13, 250 lb Wingspan, b = 40 ft TEC 2024-14 Aluminum Modulus of Elasticity, E = 10.7 x 10* 1b/in? Density, p = 0.00311 slug/in' Yield Strength, g, - 42,000 16/6n? Ultimate Strength, 0, - 57,000 lb/in? a. Calculate the maximum moment on the wing root at the centerline, at maximum gross weight and at a load factor of n = 4. Assume the lift load acts at% of the half-span of the wing measured from the centerline b. The wing spar is a rectangular shape that is one foot high and 0.2 feet wide at the root The spar is made of 2024-T4 Aluminum. Assuming all the structural load is absorbed by the spar, calculate the maximum normal stress on the spar at a load factor of n = 4, c. Engineers at Hawker seek to increase the top speed of the Hawker Typhoon aircraft by making the wing thinner thereby increasing the critical Mach number. The design change will require the main wing spar height to be reduced to 70% of the original spar height Assume the spar is a simple rectangular shape made of 2024-T4 Aluminum. The maximum gross weight and load factor and material of the redesigned wingspar will be the same, so the moment and limit load remains the same as the original Typhoon (calculated in part b). Calculate the weight change of the re-designed wing spar.