December 1, 2003PDR1 Team 5 Structures and Weights PDR #2 Scott Bird Mike Downes Kelby Haase Grant Hile Cyrus Sigari Sarah Umberger Jen Watson

December 1, 2003PDR2 Preview Tail Beam Sizing Pod Support Wing And Landing Gear Attachment Fuselage Layout Parts List and Weight

December 1, 2003PDR3 Walk-around Tractor Engine Data Boom Simple Fuselage Design Robust Wing Detachable Pod

December 1, 2003PDR4 Boom Sizing Tail boom sizing requirements: – support the maximum loading conditions Maximum elevator and rudder deflections –Small angle of twist –Small deflection Assumptions and Chooses –5g (5 times gravity) is maximum lift loading –Boom support is fixed to fuselage –Spruce L el L rdr L el L rdr

December 1, 2003PDR5 Maximum Loading Maximum Lift of Rudder and Elevator –Maximum Velocity –Maximum Coefficient of Lift Maximum deflection Maximum Bending Moment –Longest Moment arm Max bending at fixed end x Lift

December 1, 2003PDR6 Tail Boom Property Requirements Requirement: –M y = maximum bending moment –z=distance from centroid to farthest edge –σ xx = ultimate yielding stress (material property) –Iy= Moment of Inertia of cross section Requirement: θ small degree at tip in Appendix Requirement: is small –E=Young’s Modulus (material property) –I=depends on cross section L P

December 1, 2003PDR7 Stress Criteria

December 1, 2003PDR8 Twist Criteria

December 1, 2003PDR9 Tip Deflection

December 1, 2003PDR10 Tail Boom Cross Section Properties Compare Cross-Sections to Minimize Weight –Two Rectangles –Box Beam –Circular c h t x y c h d t Two RectanglesBox BeamCircular Wall thickness (in)½¼¾ Height(in)43.54 Distance Between(in) 2.5 N/A Weight (lbf)

December 1, 2003PDR11 Pod Support Considerations –Light Weight –Support Payload –Easily Removable Two Supports Aluminum Rods –Removable –Spacers Brackets to hold Pod in place Results=2.2lbs each –Too heavy? hfhf Spacer

December 1, 2003PDR12 Wing Attachment Desirables –Easy to remove –Support the wing Elastic Bands –Easy to apply and remove Spruce Rods Solid Skin between Attachments Wing Attachments

December 1, 2003PDR13 Landing Gear Attachment Failure without disaster –Vertical Buckle resistant –Horizontal Fail before vertical in joint Desired result –If Horizontal at fails joints first not much structural damage Vertical Horizontal

December 1, 2003PDR14 Fuselage Layout Considerations –Support all components Engine Electronics Pod Wing Landing Gear Tail –Simple Easy to build –Aerodynamic Smooth transitions Foam Composite Skins Ribs for shape

December 1, 2003PDR15 Part’s List Yellow- Estimated Blue -Program Estimated Fuselage Weight not complete ItemWeight (lbf) Prop0.25 Engine2.04 Fuel Tank1.00 Reciever 0.11 Battery 0.21 Wing7.45 Aft fuselage boom6.25 Pod20.00 ServoS S S Tail4.13 Fuselage6.80 Landing gear2.50 Total weight51.26

December 1, 2003PDR16 Finishing Touches…. Analysis booms support of fuselage Pod brackets, Spacers, and Bolts Add Solid Skin to Wing Ailerons Attachment Engine and other Support Finalize Weight Update when other values changes

December 1, 2003PDR17 Questions? Questions??

December 1, 2003PDR18 Material Properties PropertyAluminumBalsaSprucePine Max bending stress (lb/in^2) 47e32.2e e3 Shear Modulus (lb/in^2) 4e63.13e41.73e59.38e4 Young’s Modulus (lb/in^2) 10e6.5e61.6e61.5e6 Density (lb/in^3) ” Selection and use of Engineering Materials ”, J.A. Charles

December 1, 2003PDR19 Wing Box Properties (Rotation Requirements) Requirement: θ<1 degree at tip –T=Lift*(distance to shear center) –L=Half span –dis=distance between spars trtr b hrhr tftf hfhf