2. Consider an a/c with a mass of 950 kg. The structure of that a/c is...

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2. Consider an a/c with a mass of 950 kg. The structure of that a/c is being designed to sustain a pull-out from a dive speed of 152 m/s within a minimum maneuver radius of 942 m below which the limit load factor of the a/c is exceeded. a) What is the limit load factor for which the aircraft is being designed? 2 marks b) What is the total lift L (in N) corresponding to the above load factor? 2 marks c) Defining the wing design bending moment as that found at the wing root at ultimate loads and assuming it is solely due to the ultimate lift force on each wing (0.5L), what is that bending moment (in N.m)? Assume the wing load bearing structure to be a straight cantilever beam 9 m long and the resultant lift force is at 1/3 that distance from the wing root (see graphic below). 4 marks d) Assuming the wing beam is of rectangular thin wall cross section, 100 mm height by 500 mm width with a uniform wall thickness t, propose a design value for t in mm if the allowable strength of the chosen material is 280 MPa. 12 marks 0.5 Lult 9m Beam's cross section Note: When determining the moment of inertia I you may neglect the terms that contain higher powers of t (for example t3) considering its small value relative to the overall dimensions of the cross section. 2. Consider an a/c with a mass of 950 kg. The structure of that a/c is being designed to sustain a pull-out from a dive speed of 152 m/s within a minimum maneuver radius of 942 m below which the limit load factor of the a/c is exceeded. a) What is the limit load factor for which the aircraft is being designed? 2 marks b) What is the total lift L (in N) corresponding to the above load factor? 2 marks c) Defining the wing design bending moment as that found at the wing root at ultimate loads and assuming it is solely due to the ultimate lift force on each wing (0.5L), what is that bending moment (in N.m)? Assume the wing load bearing structure to be a straight cantilever beam 9 m long and the resultant lift force is at 1/3 that distance from the wing root (see graphic below). 4 marks d) Assuming the wing beam is of rectangular thin wall cross section, 100 mm height by 500 mm width with a uniform wall thickness t, propose a design value for t in mm if the allowable strength of the chosen material is 280 MPa. 12 marks 0.5 Lult 9m Beam's cross section Note: When determining the moment of inertia I you may neglect the terms that contain higher powers of t (for example t3) considering its small value relative to the overall dimensions of the cross section.