Christopher Cottingham The Black Pearl AME 441: Senior Design Group 1 Ryan Cobb Jacob Conger Christopher Cottingham Travis Douville Josh Johnson Adam Loverro Tony Maloney

Design Proposal Design Drivers Objectives Low-Drag Flying Wing Maximum Level Speed Maximum Climb Rate Objectives Increase Available Power Decrease Drag Decrease Weight Low-Drag Flying Wing With Drag-reducing winglets

Initial Design Considerations Stability Wing Sweep Wing Twist Reflexed Camber Line Airfoils Proper Payload Arrangement Winglets Fabrication No fuselage or tail Fewer control surfaces Takeoff & Landing Takeoff Sled Landing Skids Payload Arrangement Increased Root Thickness Internal Storage ~ 70 in3 interior

Paoli Flying Wing (unpowered) Comparison Aircraft The Black Pearl Zagi XT Surikaty XE2-400 Paoli Flying Wing (unpowered) Thunder Tiger TOW (lbs) 4.2 2.125 3.5 1.5 2.05 4.8 Wing Span (ft) 5.8 4 6.42 8.7 5.02 Wing Area (in2) 707 425 751 502 966 400 Wing Loading (oz/in2) 0.095 0.08 0.75 0.05 0.034 0.192

Fuselage Design No Actual Fuselage Wing root thickened to accommodate payload Optimized airfoil fuselage shape

Wing Bubble

Stability Design Payload arrangement Wing Sweep: 20o Aerodynamic Twist C.G. Forward of A.C. Positive Static Margin (SM = 0.11) Wing Sweep: 20o Aerodynamic Twist Reflexed Camber Line Airfoil Low (or positive) moment coefficient

Aerodynamic Wing Twist

Stability Design Winglets Reflexed trim position Enhance directional stability Wing alone is directionally stable Reflexed trim position

Control Surfaces Preliminary: Final: Sf/Sw = 0.2958 Sa/Sw = 0.1225 Plane Flaps CL= 1.5 with flaps CL= 1.0 without flaps Final: Flaps Unnecessary Flaps & Ailerons Linked Elevons enhance control authority

Engine Performance Astro 15 Static Thrust T/W Ratio Predicted Thrust: 6.0 lbf Actual Thrust: 3.15 lbf T/W Ratio Predicted: 0.96 Actual: 0.75 12 x 6 Pusher Propeller 12 Cell Battery http://www.flyhobbies.com/astroflightcobalt15geared.htm

Battery Complications 12 Ni-Cad Cells spliced to custom fit forward in bubble Learning Curve Discharging, charging problems Soldering Connections

Takeoff Sled Steerable sled for 211 ft. takeoff roll Carbon-reinforced Ply Base Dowels through wing

Sled Complications Field bumps/wind gusts change effective angle of attack on each half-span. Asymmetric lift-off causes binding in dowel slots. Mechanical forces magnify friction on dowels. Solution: Hand Launch

Structure Two main basswood spars Carbon fiber carry-through spar Root section 3.25” x 14” cutout for propeller Thin Balsa wood skin

Propellers courtesy of H2 Landing Skids Two plastic skids arranged symmetrically Protected propeller Absorbed landing impact Motivation for Design Propellers courtesy of H2

On-board GPS Data

Conclusions Conceptual Final % change Max Velocity (fps)   Conceptual Final % change Max Velocity (fps) 98 77 -21.43 Climb Rate (fps) 10 9.5 -5.00 Takeoff Weight (lb) 6.26 4.2 -32.91 Thrust-to-weight 0.96 0.75 -21.88 Wing Loading (oz/in2) 0.125 0.095 -24.00 Winglet Area (in2) 44 23.625 -46.31 Bubble Volume (in3) 70 Span (ft) 5.8 Aspect Ratio 6 Elevon Area (in2) 21 73.8  251.4 

Questions