Structures Overview Material Properties Structures Construction Landing Gear Center of Gravity Weight and Cost Estimation V-n Diagram Wing Loading Analysis March 24, 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 72.5 EPP Foam 1.3 1000 4000 Epoxy 0.0625 lb/ft2 500 14500 Ultrakote 0.0156 lb/ft2 N/A Values from Fall ’04 AAE 451 projects and http://www.matweb.com March 24, 2005

Wing Structure March 24, 2005

Fuselage Structure Formers Stringers Outer Fuselage (each): Six - 1” radius Main Fuselage: Four - 2” radius One - 1” radius Stringers Outer Fuselage (each): Seven – 1/8” x 1/8” x 36” One – 1/8” x 1/2” x 36” (for landing gear mounts) Main Fuselage: Eight – 1/8” x 1/8” x 20” Balsa sticks March 24, 2005

Tail Structure March 24, 2005

Construction March 24, 2005

Landing Gear Wire mounting Interchangeable Rigid Lightweight Inexpensive Easy to construct Interchangeable Smooth takeoff and landing on AstroTurf® Pictures courtesy of http://www.dubro.com March 24, 2005

Gear Configuration Location Configuration Front gear by canard Back gear by wing Configuration Wire strut attached to spar in outer fuselage with mounting bracket Interchangeable with wheels, skis, and floats attached to mounting blocks Fuselage Attachment Wheel/Ski/Float Attachment Pictures courtesy of http://www.dubro.com March 24, 2005

Center of Gravity Xcg = 1.708 ft Xnp = 1.856 ft Static Margin = 14.8% March 24, 2005

Weight Estimation March 24, 2005

Cost Estimation March 24, 2005

V-n Diagram Level Flight Turning Flight Max Load Factor Vdive ~ 50% higher than Vcruise nmax=2.7778-g @ Vloiter = 25 ft/sec Typical limit load factors for general aviation (npositive = 3.0-g, nnegative = -1.5-g) from Raymer, Daniel P., Aircraft Design: A Conceptual Approach p.407 March 24, 2005

Wing Loading Analysis March 24, 2005