Structures and Weights 1 QDR AAE 451: Team 2 Michael Caldwell Jeff Haddin Asif Hossain James Kobyra John McKinnis Kathleen Mondino Andrew Rodenbeck Jason Tang Joe Taylor Tyler Wilhelm February 15, 2005

Overview Wing Structure Wing Loading Analysis Landing Techniques Geometric Layout Properties of Wing Box Material Properties Structural Geometry Wing Loading Analysis Landing Techniques Weight Estimate February 15, 2005

Aircraft 3-View Mission Requirements 15 min. endurance Take-off distance ≤ 60 ft. Vstall ≤ 15 ft./s Vloiter ≤ 25 ft./s 35 ft. turn radius February 15, 2005

Geometric Layout February 15, 2005

Properties of Wing Box Shear Web Wing Spar Ribs Stringers 1.6 in. x 0.125 in. (0.1333 ft. x 0.0104 ft.) Wing Spar Central I beam located at maximum wing thickness With shear web and two stringers Ribs Balsa 20 ribs spaced approximately every 3 inches Stringers 0.375 in. x 0.375 in. (0.03125 ft. x 0.03125 ft.) leading edge stringer 0.375 in. x 0.75 in. (0.03125 ft. x 0.0625 ft.) trailing edge stringer for mounting aileron Monokote wing covering All parts: 11 lbf/ft3 balsa High safety factor (oversized web/stringers) February 15, 2005

Material Properties Density (lbf/ft3) Young’s Modulus (ksi) Yield Stress (psi) Balsa 11 625 1725 Spruce 34 1500 8600 EPS Foam 1.5 320-360 Epoxy 0.007 oz/in2 Monokote 0.0021 oz/in2 February 15, 2005

Structural Geometry Balsa construction Monokote covering Lightweight Simple, quick construction Monokote covering February 15, 2005

Wing Loading Analysis Constraints Analysis Load Distribution at Maximum Wing Loading Maximum Wing Root Bending Moment Maximum Torsional Moment February 15, 2005

Bending Worst case simplification cantilevered beam uniform load distribution negligible outer fuselage mass/support February 15, 2005

Twisting Moment due to lift found from moment coefficient February 15, 2005

Constraints Twisting: less than one degree of twist Bending: bending stress less than balsa yield stress (w/ safety factor of 2) February 15, 2005

Analysis Maximum wing load: Maximum bending moment (at root): 1.97 lbs of lift, assuming uniform distribution and span Maximum bending moment (at root): 1.308 ft-lbs Maximum torsional moment (from Cm): 0.194 ft-lbs February 15, 2005

Landing Techniques Belly Landing Conventional Landing Gear Landing Skis Parachute Catching Net February 15, 2005

Weight Estimate Weights of parts: Fuselages: 0.317 lbf Wing: 0.579 lbf Canard: 0.133 lbf Tails: 0.146 lbf Motor: 0.172 lbf Batteries: 0.113 lbf Distance measured from front of aircraft CG = 1.482 ft AC = 1.589 ft Static margin = 10.7% February 15, 2005

Summary Questions? Wing Structure Wing Loading Analysis Geometric Layout Properties of Wing Box Material Properties Structural Geometry Wing Loading Analysis Landing Techniques Weight Estimate Questions? February 15, 2005

Appendix February 15, 2005

Airfoil Selection: Wing Wortmann FX 63-137 Wortmann FX 63-137: M.S.Selig,J.F.Donovan and D.B.Fraser,"AIRFOIL AT LOW SPEEDS” – Wind Tunnel February 15, 2005

Airfoil Selection: Canard NACA 0012 February 15, 2005