March 24, Critical Design Review Michael Caldwell Jeff Haddin Asif Hossain James Kobyra John McKinnis Kathleen Mondino Andrew Rodenbeck Jason Tang Joe Taylor Tyler Wilhelm AAE 451: Team 2

[ ] [ ] March 24, Overview Walkaround Aircraft 3-View Constraint Diagram Physical Properties Aerodynamics Dynamics & Controls Structures, Weights, & Landing Gear Propulsion Unique Aspects of the Design Constraint Diagram Revisited

[ ] [ ] March 24, Walkaround

[ ] [ ] March 24, ft 3.00 ft Aircraft 3-View Mission Requirements 15 min. endurance Take-off distance ≤ 60 ft. V stall ≤ 15 ft/s V loiter ≤ 25 ft/s 35 ft. turn radius Weight1.96 lbs Wingspan5.24 ft Length3.00 ft Height1.50 ft Aspect Ratio5.24 Cruise Speed23 ft/s Max Thrust1.00 lb

[ ] [ ] March 24, Constraint Diagram Design Space Design Point Wing Loading:  lbf/ft2 Power Loading:  lbf/hp LiPoly Weight: 1.97lb f Wing Area: 5.24 ft 2 Power: hp Takeoff

[ ] [ ] March 24, Tabular Summary of Parameters Wing Area5.24 ft 2 Canard Area1.432 ft 2 Tail Area (each)0.915 ft 2 Wetted Area23.08 ft 2 Mean Chord1.00 ft Wing Taper Ratio0.7 Landing GearSkis (interchangeable) Motor TypeBrushless Wing Dihedral 4º Canard Dihedral-4º Center of Gravity1.70 ft Neutral Point1.85 ft Static Margin14.80% Foam & Balsa Construction Pitch Rate Feedback to Elevator

[ ] [ ] March 24, Concept Selection Objectives Selected mission objectives Assigned rankings (out of 120 possible points)

[ ] [ ] March 24, Weighted Objectives For each design, objectives are ranked either:  1 - Poor, 3 - Average, 9 - Excellent Each objective score is multiplied by corresponding weighted average Scores for each design concept are totaled

[ ] [ ] March 24, Pugh’s Method All other designs’ objectives are compared to design 1 (datum)  + (better), - (worse), s (same) Sum of each scoring criteria taken Design strengths and weaknesses determined

[ ] [ ] March 24, Aerodynamics Overview Airfoil Selection Twist Distribution Mathematical Model Launch Conditions L/D MAX

[ ] [ ] March 24, SELIG – WORTMANN COMPARISON Selig 1210: M.S.Selig,J.J.Guglielmo,A.P.Broeren and P.Giguere,"Summary of Low-Speed Airfoil Data, Volume 1 – Wind Tunnel Data Wortmann FX : M.S.Selig,J.F.Donovan and D.B.Fraser,"AIRFOIL AT LOW SPEEDS – Wind Tunnel Airfoil Selection: Wing

[ ] [ ] March 24, Airfoil Selection: Wing Wortmann FX Wortmann FX : M.S.Selig,J.F.Donovan and D.B.Fraser,"AIRFOIL AT LOW SPEEDS – Wind Tunnel

[ ] [ ] March 24, Airfoil Selection: Canard NACA 0012

[ ] [ ] March 24, Airfoil Selection: Vertical Tails Flat Plate  Non-Lifting Surface  No Volume Needed  Ease of Construction  Light Weight

[ ] [ ] March 24, Wing Twist Distribution Root: 1 o Tip: -7 o

[ ] [ ] March 24, Mathematical Model Prandtl’s Classical Lifting Line Theory  Elliptical Loading Parasite Drag – Component Buildup Method

[ ] [ ] March 24, Mathematical Model From Prandtl’s Classical Lifting-Line Theory

[ ] [ ] March 24, Mathematical Model Re=147,820

[ ] [ ] March 24, Mathematical Model C Mo calculated using Roskam Vol. VI and C Mα calculated from flatearth.m

[ ] [ ] March 24, Launch Conditions α Lo = -9 o V take-off = 1.2V stall = 18 ft/s Climb Angle = 20 o Angle of Attack = 4.5 o -9 o 20 o 4.5 o

[ ] [ ] March 24, L/D MAX L/D MAX =10.75 α L/Dmax =0.60 o Re=147,820

[ ] [ ] March 24, L/D MAX L/D MAX Velocity Loiter Straight:  V L/Dmax = ft/s Re=147,820 Operation Point

[ ] [ ] March 24, Dynamics & Controls Overview Tail Sizing Control Surface Sizing Static Margin Trim Diagram Dihedral Angle Feedback System

[ ] [ ] March 24, Tail Sizing (Class 1) Constants  c HT = 0.50  c VT = 0.05  C w = 1 ft  S w = 5.24 ft  L HT = 1.83 ft  L VT = 0.75 ft Horizontal tail (canard)  Area = ft 2 Vertical tail  Area = ft 2 (each)

[ ] [ ] March 24, Tail Sizing (Class 2) Vertical Tail  Plot C nβ versus S vt  S vt = ft 2

[ ] [ ] March 24, Tail Sizing (Class 2) Horizontal Tail  Plot X cg and X ac versus S ht  S ht = 1.36 ft 2

[ ] [ ] March 24, Canard & Tail Sizing Class 1 SizingClass 2 Sizing Canard Area S ht 1.43 ft ft 2 Vertical Tail Area S vt (each) 0.92 ft ft 2

[ ] [ ] March 24, Control Surface Sizing Span (ft)Chord (ft)Area (ft 2 ) Aileron (each) Elevator Rudder (each)

[ ] [ ] March 24, Desired Static Margin Static Margin (Raymer)  Typical Fighter Jet: 0-5%  Typical Transport Aircraft = 5-10%  Model aircraft usually more stable Goal: Static Margin = 15%

[ ] [ ] March 24, Actual Static Margin X cg = 1.70 ft X np = 1.85 ft Static Margin = 14.80%

[ ] [ ] March 24, C L Max Trimmed Maximum C L (x ref = x cg ) α CL Max α = 0 o Trim Diagram

[ ] [ ] March 24, Outer Panel Dihedral Wing: 4 deg outer panel dihedral, B=4 deg and x at 0.9 ft Canard: -4 deg outer panel dihedral, B=4 deg and x at 0.08 ft Dihedral Angle

[ ] [ ] March 24, Dihedral Angle EVD of the wing and canard: Wing EVD: Canard EVD:

[ ] [ ] March 24, Loop Closure Description Pitch Rate feedback to the Elevator Objective: Establish longitudinal stability by using pitch rate feedback by varying damping ratio of the short period mode from 0.83 to 0.99.

[ ] [ ] March 24, Block Diagram H e (s) q(s)/  e (s) H (s)K  Pilot Input Elevator Servo Aircraft  e (s ) q(s) + _ Pitch Rate Gyro Feedback Gain

[ ] [ ] March 24, Aircraft TF / Natural Frequency and Damping Ratio Aircraft Transfer Function (Flat Earth Predator) Undamped Natural Frequency (Short Period) Damping Ratio (Short Period)

[ ] [ ] March 24, Gain Calculation, k Gain Calculation: - Flat Earth Predator - SISOTOOL k = Root Locus Plot For k = 0 For k =

[ ] [ ] March 24, Root Locus

[ ] [ ] March 24, Root Locus

[ ] [ ] March 24, Gyro and Servo Selection Futaba GYA350 gyro  Weight: 0.92 ounces  Remote gain function JR S241 sub micro servos  Weight: 0.32 ounces  Torque: 17 oz/in

[ ] [ ] March 24, Structures Overview Material Properties Structures Landing Gear Center of Gravity Weight and Cost Estimation V-n Diagram Wing Loading Analysis

[ ] [ ] March 24, Material Properties Density (lb f /ft 3 )Young’s Modulus (ksi)Yield Stress (psi) Balsa Spruce EPS Foam EPP Foam Epoxy lb/ft Ultrakote lb/ft 2 N/A Values from Fall ’04 AAE 451 projects and

[ ] [ ] March 24, Structural Geometry Primarily EPP Foam Balsa fuselage structures

[ ] [ ] March 24, Wing – Fuselage Attachment

[ ] [ ] March 24, Fuselage Structure Formers  Outer Fuselage (each): Three - 1” radius  Main Fuselage: Four - 2” radius Stringers  Outer Fuselage (each): Seven – 1/8” x 1/8” x 36” One – 3/8” x 1/2” x 36” (for landing gear mounts)  Main Fuselage: Eight – 1/4” x 1/4” x 20”

[ ] [ ] March 24, Tail Structure Flat Plate  Non-Lifting Surface  No Volume Needed  Ease of Construction  1/8” Balsa – Lightweight  EPP Foam Rudder

[ ] [ ] March 24, Landing Gear Wire mounting  Rigid  Lightweight  Inexpensive  Easy to construct Interchangeable Smooth takeoff and landing on AstroTurf ® Pictures courtesy of

[ ] [ ] March 24, Location  Front gear by canard  Back gear by wing Configuration  Wire strut attached to stringer in outer fuselage with mounting bracket  Interchangeable with wheels, skis, and floats attached to mounting blocks Gear Configuration Pictures courtesy of Fuselage Attachment Wheel/Ski/Float Attachment

[ ] [ ] March 24, Weight Estimation

[ ] [ ] March 24, Cost Estimation

[ ] [ ] March 24, V-n Diagram Level Flight Turning Flight Max Load Factor V dive ~ 50% higher than V cruise n max V loiter = 25 ft/sec Typical limit load factors for general aviation (n positive = 3.0-g, n negative = -1.5-g) from Raymer, Daniel P., Aircraft Design: A Conceptual Approach p.407

[ ] [ ] March 24, Wing Loading Analysis Analysis  Load Distribution and Maximum Wing Loading  Maximum Wing Root Bending Moment  Maximum Torsional Moment  Maximum Wing Tip Deflection  Maximum Bending Stress

[ ] [ ] March 24, Bending Worst case simplification  Cantilevered beam  Negligible weight, outer fuselage mass/support  Elliptical load distribution

[ ] [ ] March 24, Twisting Moment due to lift found from moment coefficient

[ ] [ ] March 24, Constraints Twisting: less than one degree of twist Bending: bending stress less than EPP foam yield stress (w/ safety factor of 2)

[ ] [ ] March 24, Analysis Maximum wing load:  1.97 lbs of lift, elliptical loading, load factor of 2.77 yields 5.45 lbs Maximum bending moment (at root):  ft-lbs Maximum torsional moment (from C m ):  ft-lbs

[ ] [ ] March 24, Results Maximum wing stress: psi Maximum tip deflection: 0.16 in. Maximum rotation: 0.13 degrees

[ ] [ ] March 24, Moments and Products of Inertia Balsa Components: Volume = (+/ ) cubic inches Volume Centroid = ,2e-007, (+/- 8.6e-006,2.2e- 006,1.2e-005) Volume Moments: Volume Moments of Inertia about World Coordinate Axes Ix: (+/ ) Iy: (+/ ) Iz: (+/ ) Volume Moments of Inertia about Centroid Coordinate Axes Ix: (+/ ) Iy: (+/ ) Iz: (+/ ) Foam Components: Volume = (+/ ) cubic inches Volume Centroid = ,1.1e-005, (+/- 3.5e- 006,2.7e-006,2.4e-006) Volume Moments: Volume Moments of Inertia about World Coordinate Axes Ix: (+/ ) Iy: (+/ ) Iz: (+/ ) Volume Moments of Inertia about Centroid Coordinate Axes Ix: (+/ ) Iy: (+/- 0.11) Iz: (+/ ) Calculated from CAD Model Multiply by material density to determine Mass MOI

[ ] [ ] March 24, Propulsion Overview Propeller Selection Component Trade Study Motor & Battery Selection

[ ] [ ] March 24, Prandtl & Goldstein

[ ] [ ] March 24, Propeller Efficiency and Advance Ratio Operation Range  J =

[ ] [ ] March 24, Thrust Coefficient and Advance Ratio

[ ] [ ] March 24, Propeller Efficiency and Advance Ratio

[ ] [ ] March 24, Propeller Selection

[ ] [ ] March 24, Component Trade Study Graupner Speed % too powerful, unreliable data Each “Tier” represents a battery / motor combination More selection with Li & Brushless Connectors for brushed motors and Li batteries are not compatible. It would not be wise to have a Li & brushed combination. Our Aircraft needs to weigh less than 32 oz Our Aircraft

[ ] [ ] March 24, Thrust, Power, and Endurance Airspeed Amps “Sedate” Mission 15min Airspeed Amps “Trainer” Mission 23min

[ ] [ ] March 24, Motor & Battery Selection ComponentsProp 2 Code Calculates near 900mAh necessary to fly mission Fails to include component energy requirements Components need approximately 150mAh across our mission 1050mAh battery necessary Kokam 1200mAh battery chosen on grounds of weight & preferred vendors

[ ] [ ] March 24, Unique Aspects of the Design Twin Boom Design EPP Foam Robust Interchangeable Landing Gear Brushless Motor 3-Bladed Prop Alternative

[ ] [ ] March 24, Remaining Design Problems Updating SURFCAM Possible Wing Area Updates Landing Gear Position

[ ] [ ] March 24, Constraint Diagram Revisited Design Space Current Design Point Weight:  2.06 Lbf Wing Area  5.30 ft 2 Power:  0.06 hp Wing Loading:  0.39 lbf/ft2 Power Loading:  lbf/hp Desired Design Point Takeoff

[ ] [ ] March 24, Summary Walk Around Aircraft 3-View Constraint Diagram Physical Properties Aerodynamics Dynamics & Controls Structures, Weights, & Landing Gear Propulsion Unique Aspects of the Design Constraint Diagram Revisited

[ ] [ ] March 24, Questions?

[ ] [ ] March 24, Appendix

[ ] [ ] March 24, Turning Conditions

[ ] [ ] March 24, L/D Mathematical Model * Raymer, Daniel P., Aircraft Design: A Conceptual Approach p.493

[ ] [ ] March 24, L/D MAX L/D MAX Velocity Loiter Straight:  V L/Dmax = ft/s Loiter Turn:  V L/Dmax = ft/s Re=147,820

[ ] [ ] March 24, Effect of Control Surface Deflection: Lift Roskam,Jan, Airplane Design PartVI: Prelimenary Calculation of Aerodynamic, Thrust, and Power Characteristics, 2000

[ ] [ ] March 24, Effect of Control Surface Deflection: Pitching Moment Roskam,Jan, Airplane Design PartVI: Prelimenary Calculation of Aerodynamic, Thrust, and Power Characteristics, 2000