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3. (Adapted from Etkin and Reid, 2.5) The following data apply to a 1/25th scale wind tunnel model of a transport airplane. The full-scale mass of the aircraft is 22,680kg. Assume that the aerodynamic data can be applied to the full-scale vehicle. For level unaccelerated flight at V=239 knots (123 m/s) of the full-scale aircraft, under the assumption that propulsion effects can be ignored, (a) Find the limits on the tail angle it and CG position h imposed by the conditions Cmo and Cma <0. (b) For trimmed flight with de = 0, plot i vs. h for the aircraft and indicate where this line meets the boundaries in part (a). Geometric data • wing area S = 0.139m² (so need to scale this are up by 252 – lengths scale by 25) • wing mean aerodynamic chord c = 15.61cm • l = 38.84cm Tail area St = 0.0342m² Aerodynamic Data (does not need to scale) • Cl, = 0.077/deg (convert to radians) • Cle = 0.064/deg € = 0.72° • deg/da 0.30 • Cme = -0.018 • ha=0.25 (notes page 2-4) • p= 1.225kg/m3