1. Team 5 Structures and Weights QDR #1
Scott Bird
Mike Downes
Kelby Haase
Grant Hile
Cyrus Sigari
Sarah Umberger
Jen Watson
October 16, 2003
QDR

2. Preview Maximum Loading Conditions Span-wise Loading
Wing Box Properties
October 16, 2003
QDR

3. Maximum Loading Conditions
Assumptions
only applied load is Lift
no control surfaces
Max Bending and Torsion is at Max Lift
Max Lift at Max Velocity and Max angle of attack
October 16, 2003
QDR

4. Maximum Velocity Intersection of Drag and Thrust
At maximum Coefficient of Lift
Vmax=160 ft/s
October 16, 2003
QDR

5. Span-wise Loading Assumed Elliptical Loading Maximum at Root
Max bending at root =1265 lbf/ft
October 16, 2003
QDR

6. Wing Box Properties Assumptions and choices Front Spar Rear Spar
I-beam (efficient in bending)
Located at max thickness chord
Supports all bending moment stress
Rear Spar
Rectangle
Located at 60% chord
Included in torsion (polar moment)
Lift is at ¼ chord
Aluminum
Web Thickness is equal for Front and Rear Spar
Skin Thickness is constant
October 16, 2003
QDR

7. Wing Box Properties (Rotation Requirements)
J=T/Gθ
θ <1 deg/unit span (1.2 safety factor)
Shear Modulus (G) material property
Aluminum=576e6 lbf/ft^2
T=Lift*horizontal distance from centroid
J=polar moment of inertia
Web
tw=.01 ft = .12 in
Skin
1.93e-3 ft =.023 in
October 16, 2003
QDR

8. Wing Box Properties (Bending Moment Prop)
Iy=My*z/σxx
My = maximum bending moment
z=distance from centroid to farthest edge
σxx = ultimate yielding stress (material property)
Iy= Moment of Inertia of cross section
October 16, 2003
QDR

9. Wing Box Properties Front Spar tw Rear Spar c
Chosen b=.05 ft =.6in
c=.125 ft and h is determined by the thickness of the airfoil
Rear Spar
d = .05 ft is determined by the thickness of the airfoil
Iy=(b(2c)3-h3(b-tw))/12= e-005 ft^4
Iy min =2.3379e-005 ft^4 tw c d h tw b
October 16, 2003
QDR

10. Landing Gear Wing Ribs Different materials Weights Center of Gravity
Results to come….
Landing Gear
Wing Ribs
Different materials
Weights
Center of Gravity
Moments of Inertia
October 16, 2003
QDR

11. Questions?
Questions??
October 16, 2003
QDR