1 Aerial Search and Supply ( ASnS) AAE 490K Project Bill Fredericks Joel Gentz Phil Wagenbach Cynthia Fitzgerald Ben Jamison

2 Overview Mission Concept Requirements Constraint Analysis Parasitic Drag Estimation Aspect Ratio Sizing Weight Estimation Propulsion Wing and Tail Geometries Structural Design Wing Spar Loading Fuselage Tests Hardware and Electronics Fuselage Design Wing Attachment Method Basic Construction Method

3 Mission Concept Take off from a small field Autonomously search disaster area for victims with onboard autopilot/GPS using camera payload Upon finding victim mark waypoint Aircraft sprints back to field and lands Camera payload is changed out for med kit and supplies to be dropped on victim Aircraft takes off and sprints back to victim and drops payload Returns and lands Cost must be within the capability of city fire departments

4 Requirements 5 lb Payload Camera, Transmitter, and Batteries or Water, Food, and Medical Kit 50 yard Unassisted Takeoff (Paved Surface) 90 mph Sprint Capability 25 mph Stall Speed 1 hour Endurance

5 Constraint Analysis Takeoff Sprint Stall Speed Landing

6 Parasitic Drag Estimation Typical single engine GA airplane (From Raymer) C Do =.022 C Dwet =.0055 Only Skin Friction Drag (Re = 200,000 Turbulent) C Dwet =.003  C Do =.0124 Lower wetted / wing area ratio of our aircraft leads to less drag C Do =.0207 Used C Do =.024 in constraint analysis to be more conservative

7 Aspect Ratio Choice CDo =.03 This is even more conservative than the constraint analysis to be sure we hit L/D of 10 Oswald’s Factor =.7 Weight = 1 Settled on an Aspect Ration of 7

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9 Constrain Analysis Inputs rho = (slug/ft 3 ) C Lmax = 1.2 g = 32.2 (ft/s 2 ) Takeoff and Landing Distance = 150 (ft) Braking Force Fraction =.3 (lbf/lbf) Stall Speed = 25 (mph) Oswald’s Factor =.7 AR = 7 Sprint Speed = 90 (mph) CDo =.024

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11 Weight Estimation Assumptions L/D = 10 E Loiter = 1 (hr) C =.133 (1/hr) W Takeoff = 21.6 (lb) W Payload = 5.0 (lb) W Fuel = 1.5 (lb) W Empty = 15.1 (lb) Loiter Takeoff Climb Landing

12 Thrust Specific Fuel Consumption Assumptions c bhp =.6 lb Fuel /(hp*hr) Honda 6000 RPM η prop = 60% V = 50 mph TSFC Notes: Typical GA .25 High-Bypass Jet .4 Low-Bypass Jet .7 Pure Jet .8 Aircraft Design: A Conceptual Approach Daniel P. Raymer AIAA Education Series

13 Design Point Wing Loading = 1.91 lb/ft 2 (30.56 oz/ft 2 ) Wing Area = ft 2 Thrust to Weight =.28 Thrust = 6.05 lb Speed = 90 mph Power = 1.45 hp

14 Propulsion Modify small string trimmer engine rpm Honda GX35, mini 4- stroke engine ( ) Most efficient and light engine (5.75 lbs before conversion) Carr Precision, Oregon $530 for a converted engine (

15 Wing Sizing Based on the wing loading calculated in constraint analysis (1.91 lbs/ft^2) Aspect ratio from ideal L/D vs. CL plot

16 Tail Sizing Our computed wing geometry: Area= ft 2 Chord length= 1.27ft Wing Span= 8.89 ft Possible values (pulled from Raymer) for General Aviation single engine: Horizontal C HT : 0.70 Vertical C VT : 0.04 Equations: S VT = C VT *b w *S w /L VT S HT = C HT *C w *S w /L HT Computed Tail Areas: S VT = (0.04)*(8.8ft)*(11.31ft 2 ) / (3.5ft) = ft 2 S HT =( 0.70)*(1.27ft)*(11.31ft 2 ) / (3.5ft) = ft 2 *Using 42in. (3.5ft) for L VT and L HT

17 Airfoil Shape Researched both Epler and NACA airfoils Compared NACA4412 and E-193…very similar Planning on using NACA4412 (common use, more data)

18 Airfoil Characteristics

19 Airfoil Characteristics

20 Wing Spar Loading Takeoff Weight25 lbsSpan8.88 ft G Loading3Span Loading16.89 lbs/ft Safety Factor2Root Shear75 lbs Design Load150 lbsRoot Moment ft*lbs

21 Wing Spar Dimensions Balsa didn’t have the strength Wing spar will be made of sitka spruce Cord1.27 ftSpar Depth1.7 in % Thick.12Wood TypeSitka Spruce Wing Depth.1524 ftσxσx 5613 lbs/in 2 Wing Depth inSpar cap.5 in x.8025 in

22 Wing Shopping List Ribs Need 41 (8.88’ / 3” = 35.2 ribs) Plus one for the end Plus 2 for dihedral Plus 2 for extra root attachment 4 will be 1/8” plywood at root attachment Should be extra cross section plywood 13 1/8” x 2” x 48” Spar need 2 1” x ½” x 5’ (Spruce) Spar need 2 1” x ½” x 5’ (Balsa) Rear Spar 4 1/8” x 2” x 3’ Leading Edge Spar 1/8” x 1/8” Use extra from rear spar Leading edge wrap Block for fuselage attachment 1” x 2” x 12”

23 Fuselage Construction Test Decided on just Balsa for simplicity and weight. Considered two ideas Stick frame ribs with skin stringers Solid Ply ribs with stick stringers

24 Fuselage Construction Test Stick frame cross sections with solid skin was far superior Weight <.2lbs for 5”x5”x12” section Held > 130 lbs. Was stood on top of by team member and only crushed top surface

25 Fuselage Shopping List Firewall – 6’’ x 6’’ x ¼’’ Ply (1) Front Ribs – 6’’ x 6’’ 1/8’’ Ply (13) Back Ribs – 6’’ x ¾’’ x 1/8’’ Balsa Sticks (14) Skin Sides – 3’’ x 6’’ x 1/16’’ Balsa Sheet (Enough for two wide on four sides) Skin Angles – 1’’ x 6’’ x 1/8’’ Balsa Sheet (Enough for 1’’ on each bottom corner for entire length)

26 Previous 490 Materials Prof Sullivan said he could help us with nearly everything List compiled so far: 6 Channel Radio transmitter/controller and receiver Servos (types: elbow vs cross etc) Servo arms Control Surface fixtures In contact with Prof Andrisani: Cannot use the “loft” or the Lockers. Need to contact Madeline

27 Controls Update -Meet at ASL with Matt and Ben to take inventory -Will be using JR XP6102 Controller/receiver combination (6 channel) -Matt still locating servo’s/control arms; plenty of elbows -Need to order -Servos, pivot arms, hinges -Pico Pilot/Micro Pilot – available to use AFTER successful flight without – can use to work basic understanding of software

28 Wing Attachment ideas Bolt through top of fuselage, set wing over bolt, fix on top of wing Canvas straps Fuselage “hat” idea

29 Wing Attachment Diagram

30 Final Fuselage Design The Fuselage will use a combination of both tested designs. The fire wall will be 6”x6”x1/4” Birch Plywood From the firewall to the T.E. of the wing will be 6”x6”x1/8” Birch Ply cross sections with 3”x1/16” Balsa skin on the sides and 1”x1/8” Balsa skin on the corners.

31 Fuselage From the T.E of the wing to the tail will be 3/4”x3/16” stick frame ribs with 3”x1/16” Balsa skin on the sides and 1”x1/8” Balsa skin on the corners, scaling down from a 6”x6” cross section to 3”x3” cross section at the tail. The entire Fuselage will be flat on top for ease of connecting the Wing and the Tail sections. Ribs will be placed every 3’’ throughout the Fuselage, except where the wing will connect to the body where there will be more.

32 Final Design The Fuselage will be 64” long. From the fire wall aft With 24” of constant cross section from the fire wall aft. All of the electronics (Micro pilot, receiver, battery and servos) will be located under the wing. The fuel tank and throttle servo will be in front of the wing

33 Aerial Search n Supply (ASnS)

34 Basic Fuselage Construction Steps The first two steps in construction will be to mount the engine mount to the firewall and cut the appropriate cross sections around the fuel tank Next, machine the plywood cross sections and make an adjustable jig for the stick frame cross sections Lay all cross sections in a foam jig and glue bottom side, ensures the top will be flat and we will be able to see the taper before we glue

35 Basic Wing Construction Steps Cut wing spars to proper dimensions Create template for ribs Machine ribs on computerized router Using foam jig assemble ribs and spars Build brackets for Servos Wing Bolts Control Surface hinges Cover front of wings with balsa skin

36 Questions?