MSD 1 WEEK 6
SYSTEM DESIGN REVIEW
Team 15462
Rochester Institute of Technology
College of Engineering
10/2/2014
P15462
1
AGENDA
Background (10 minutes)




Problem Statement
Customer Needs
Engineering Requirements
Week 3 action item review
10/2/2014
System Analysis











Functional Decomposition
Areas of Design
Solution Brainstorming
Selection Criteria
Concept Generation
Pugh Chart
Final System Selection
Concept Feasibility
Updated Project Plan
System Architecture
Risk Assessment
P15462
2
PROBLEM STATEMENT
The goal of this project is to design, build, and reliably test
an unpowered, human-controlled tethered glider specifically
for use as an Airborne Wind Turbine system (AWT).
10/2/2014
100m
250m
100mP15462
3
250m
CUSTOMER NEEDS
Customer Need #
CN1
CN2
CN3
CN4
CN5
CN6
CN7
CN8
CN9
CN10
CN11
CN12
10/2/2014
Importance
Description
9
Tethered glider system (with electric prop assist for launching) that
demonstrates at least 3 minutes of continuous circular flight path with taunt
tether.
1
Clean appearance
9
Human controlled plane
3
No special flight skill required
9
Use existing base station design
9
Tether tension is measured and recorded during flights
9
Tether direction is measured and recorded during flights
9
Videos with accompanying data files of all flight tests (even ones that don’t
work)
9
Able to survive crashes with minor repairs (short downtime)
9
Replaceable Parts
3
Maintenance Guide
9
Design a robust glider which meets the above repair requirements and can
be piloted in the cyclical path.
4
P15462
ENGINEERING REQUIREMENTS
Rqmt. # Importance
Type
Source
Engr. Requirement (metric)
Unit of Measure
Marginal
Value
Ideal Value
--
0.2
0.05
Comments/Status
Test (Verification)
S1
9
Aero
CN1
Drag Coefficient
S2
9
Aero
CN1
Lift Coefficient
--
0.7
1
S3
3
Aero
CN1
Wingspan
ft
3.3
3
S4
3
Aero
CN4
Cooper-Harper Rating
--
3
1
S5
3
Aero
CN3
Flight Stability
Binary
Marginal
S6
3
Aero
CN11 Profile of Surface for Airfoil Manufacturing
in
S7
9
Aero
CN1
-
S8
1
Aero
CN1
Fixed Angle of Attack
deg
0
3
S9
9
Electrical
CN7
Horizontal Potentiometer Recording
Binary
Marginal
Complete
Capability Exists (P14462)
LabVIEW
S10
9
Electrical
CN7
Vertical Potentiometer Recording
Binary
Marginal
Complete
Capability Exists (P14462)
LabVIEW
S11
9
Electrical
CN1
Electronics Weight
lbs
0.484
0.4
Motor not included
Scale
S12
9
Financial
CN1
Initial Cost
$
250
200
S13
3
Financial
CN10
Repair Cost
$
100
50
S14
9
Mechanical CN6
Tether Tension
lbs
5
23
S15
9
Mechanical CN1
Mechanical Weight
lbs
4
3
S16
9
Mechanical CN1
Service Ceiling
ft
75
100
S17
3
Mechanical CN1
Flight Path Diameter
ft
25
50
LabVIEW
S18
9
Mechanical CN1
Maximum Glider Speed
mph
30
45
LabVIEW
20
16
Caliper
Efficiency of Wing
Calculation & XLFR5
Calculation & XLFR5
Customer Constraint
Tape Measure
Complete
Static Stability Criteria
Calulation & Flight Testing
0.1
0.05
GD&T
ASTM Standard
0.82
0.9
Subjective
Calculation
Protractor
BOM
BOM
Capability Exists (P14462)
LabVIEW
FAA Regulation
LabVIEW
Scale
S19
3
Mechanical CN1
Fuselage Cross Sectional Area
in2
S20
9
Mechanical CN9
Fuselage Material Tensile Strength
psi
CF is ideal material
MatWeb Lookup
S21
9
Mechanical CN9
Wing Material Tensile Strength
psi
Foam Mat'l Comparison
MatWeb Lookup
S22
3
Time
CN9
Repair Downtime
hour
24
1
Stopwatch
S23
3
Time
CN8
Time Between Flights
min
30
5
Stopwatch
S24
3
Time
CN4
Training Flight Hours
hour
12
1
10/2/2014
Training Documetation
Stopwatch
P15462
5
ENGINEERING REQUIREMENTS ADDITIONS
Rqmt. # Importance
Type
Source
Engr. Requirement (metric)
Unit of Measure Marginal Value Ideal Value
Comments/Status
Test (Verification)
S7
9
Aero
CN1
Efficiency of Wing
-
0.82
0.9
Calculation
S8
1
Aero
CN1
Fixed Angle of Attack
deg
0
3
Protractor
S11
9
Electrical
CN1
Electronics Weight
lbs
0.484
0.4
S12
9
Financial
CN1
Initial Cost
$
250
200
BOM
S15
9
Mechanical
CN1
Mechanical Weight
lbs
4
3
Scale
S19
3
Mechanical
CN1
Fuselage Cross Sectional Area
in2
20
16
Caliper
S20
9
Mechanical
CN9
Fuselage Material Tensile Strength
psi
CF is ideal material
MatWeb Lookup
S21
9
Mechanical
CN9
Wing Material Tensile Strength
psi
Foam Mat'l
Comparison
MatWeb Lookup
S22
3
Time
CN9
Repair Downtime
hour
24
1
Stopwatch
S23
3
Time
CN8
Time Between Flights
min
30
5
Stopwatch
S24
3
Time
CN4
Training Flight Hours
hour
12
1
10/2/2014
Motor not included
Training Documetation
Scale
Stopwatch
P15462
6
GLIDER PURCHASE
UMX Radian BNF
 For use as Practice Tethered Glider
 Onboard Electronics Included
 Folding Prop
 Purchased from E-Flite via Amazon
 $89.99 +ship
 Radio from P14462 (Professor Kolodziej)
 Futaba 6EX-PCM
 Shipping ETA 10/1/2014
10/2/2014
P15462
7
GLIDER PURCHASE
Wingspan:
Overall Length:
Flying Weight:
Motor Size:
Radio:
CG (center of gravity):
Recommended Battery:
Flaps:
Approx. Flying Duration:
Charger:
Assembly Time:
Assembly Required:
10/2/2014
28.7 in (730mm)
16.5 in (418mm)
1.50 oz (43 g)
8.5mm coreless brushed motor
4+ channel transmitter required
1.22 in (31mm) back from the leading
edge of wing at wing root
1S 3.7V 150mAh 25C LiPo
No
8-10 minutes
1S 300mA LiPo USB Charger
Less than 1 Hour
Yes
P15462
8
AERO CLUB FLIGHT FAMILIARIZATION VIDEO
10/2/2014
P15462
9
AGENDA
Background




Problem Statement
Customer Needs
Engineering Requirements
Week 3 action item review
10/2/2014
System Analysis
 Functional Decomposition (5 min)
 Areas of Design (3 min)









Solution Brainstorming
Selection Criteria
Concept Generation
Pugh Chart
Final System Selection
Concept Feasibility
Updated Project Plan
System Architecture
Risk Assessment
P15462
10
FUNCTIONAL DECOMPOSITION
10/2/2014
P15462
11
FUNCTIONAL DECOMPOSITION
Reach Desired Altitude
Take-Off Method
10/2/2014
Engage Tether
P15462
12
FUNCTIONAL DECOMPOSITION
Sustain Tethered Flight
Flight Path
Maintain Peak Altitude
10/2/2014
Regulate Tension
Cyclical Path
P15462
13
FUNCTIONAL DECOMPOSITION
Repeatable Flight
Provide Soft Landing
10/2/2014
Easily Replaceable Parts
P15462
14
FUNCTIONAL DECOMPOSITION
Record Data
10/2/2014
Respond to on Board
Feedback
Integrate with Base
Station DAQ
Capture Video
Record Angle
Record length
Record Tension
P15462
15
10/2/2014
Respond to feedback
x
x
Capture Video
x
x
x
Record Tension
x
x
x
Record Length
x
x
x
Record Angle
x
Easily Replaceable Parts
x
x
x
Soft Landing
Maintain Cyclical Path
x
x
x
Regulate Tension
Maintain Peak Altitude
Fuselage
Wings
Horizantal Tail
Fuselage Material
Wing & Tail Material
On-Board Electronics (Control Feedback)
Take-Off Method
Tether-to-Plane Connection
Propeller Location
Non-Destructively Achieve Tether Tension
Flight Path
Non-Destructive Landing
Base Station Data Collection Program*
Engage Tether
Areas of Design
Take Off Method
FUNCTIONAL DECOMPOSITION VS.
AREAS OF DESIGN
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
P15462
16
AGENDA
Background




Problem Statement
Customer Needs
Engineering Requirements
Week 3 action item review
System Analysis
 Function Decomposition
 Areas of Design
 Solution Brainstorming (2 min)
 Selection Criteria (2 min)
 Concept Generation (2 min)
 Pugh Chart (5 min)





10/2/2014
Final System Selection
Concept Feasibility
Updated Project Plan
System Architecture
Risk Assessment
P15462
17
BENCHMARKING
Benchmarking Table
Ampyx
Wing Design
Positive dihedral, semi elliptical wing, high fixed angle of attack, flaps
Tail Design
Fuselage Design
Takeoff
Landing
Maintaining Tension
Tether Length (m)
Average Kw Creation
Large primary T-shaped rudder with small elevators
Mildly Aerodynamic/Box Fuselage with Protruding Pitot Tube
Mechanical-Electrical winch system
Lands on underside of fuselage and wings
Constant reeling in and out of figure 8 pattern
300-600 meters
15kW
*Image from Ampyx Power
10/2/2014
P15462
18
SOLUTION BRAINSTORMING (PT.1)
Fuselage
Flying Wing
Rod Type
Football Shaped
Cylindrical Shape
Wings
Swept Back
Swept Forward
High Dihedral
Low Dihedral
Horizontal Tail Fuselage Material Wing/Tail Material On-Board Electronics
Take-Off Method
Canard
EPP
EPP
Wireless Transmission
Rocket Engine
Rear Tail
ROHACELL Foam ROHACELL Foam In-Flight Data Recorder Compressed Air Cylinders
H-shape
"Other" Foam
"Other" Foam
With Software
Winch
V-Shape
Carbon Fiber
Carbon Fiber
Without Software
Hydraulic Cylinders
Inverted VTear-Drop Shape
Oblique Sweep
Plastic Coating
Plastic Coating
Spring Loaded
Shape
Box Frame "Typical"
Blended Wing
"Typical" Shape
Monocoat
Monocoat
Throw Glider
Lifting Body
Other Coating
Other Coating
Balloon Launch
Linear Chord Variation
Fiberglass
Fiberglass
Kite-Run Launch
Elliptical Chord
Aluminum
Aluminum
Tow with Truck
Variation
Winglets
Plastic
Plastic
VTOL
Bi-Wing
Wood
Wood
Tow with RC plane assistance
X-Wing
Titanium
Titanium
Drop from Tall Tower
Magnetic Rail Gun
Mid Placement
High Placement
Propeller
Low Placement
Powered Wheels
Dragon Scales
Bottle Rockets
Helicopter Propeller
Bend Tree and Slingshot
Catapult/ Trebuchet
Hot Air Balloon
Diet Coke and Mentos
10/2/2014
P15462 19
Zip-line System
SOLUTION BRAINSTORMING (PT.2)
Tether-to-Plane Connection
3-Point Bridle
2-Point Bridle
1-Point Fixed Bridle
1-Point Slider
Ball-in-Socket
Set Screw
3-Point Chuck
1 Tether per Control Surface
Propeller
Location
Front
Middle
Back
Above Centerline
Below Centerline
Non-Destructively Achieve Tether
Flight Path
Tension
Hand Spool
Horizontal Circle
Automated Spool
Offset Vertical Circle
On Board Spool
Figure 8
Spring Decellerator
Mobius Strip
Constant Force Spring
Two Tether Ellipse
Nothing (Jerk at Tension)
KiteGen Flight Path
Spring on Base Station
Roller Coaster Rail Track
Lasso Flight Path
Feedback Triggered Rocket Decellerator
Kill Propeller Power
Open Cargo Bay and Drop Line at Altitude
Tether is a Constant Force Spring
Velcro End of Tether to Release at Tension
Non-Destructive Landing
Method
Parachute
Landing Wheels
Smooth Bottom
Separate Tethered Balloon
Reverse Rockets
Tripod
Inflatable Stunt Pad
Corn Field
Skis
Gas Inflated Balloon
Air Bags/ Mars Rover
Quadcopter with Drag Net
Porous Net Raised Above
Ground
Two Tethers Which Trade Off Slack
Reverse Zipline
10/2/2014
P15462
20
SELECTION CRITERIA
 Simplicity & Effectiveness of Wing Design
 Safe Landing
 Initial Cost
 Development Time
 Replacement Part Cost
 Simplicity of Take-Off Method
 Weight
 Tether Stress on Plane
 Durability
 Tether Impulse Mitigation
 Ease of Manufacturing
10/2/2014
P15462
21
CONCEPT GENERATION
Area of Design
Devin
Maginn
Kennedy
Zebert
Carl
Fuselage Design
Football Shape
Tear Shape
Cylindrical Shape
Cylindrical
Box type with nose cone
Wing Design
Mid, High Dihedral, linear
taper
Elliptical Wing/ low mount,
Asymmetrical Dihedral
Linear Taper/Low Dihedral/Flaps
Flush transition from fuselage to
High dihedral/ linear taper
wing/ winglets
Horizontal Tail Design
H shape
Low, Asymmetrical Dihedral Rear Tail/Normal Shape
Rear Tail
Rear Tail/ Normal
Fuselage Material
Wood
Foam/ Integrate with Fuse
Other Foam/Monocoat
EPP with CF rod support
Carbon-Fibre
Wing/Tail Material
Foam
Foam with Monocoat
Yes
Yes
EPP or better with Monocoat
In-Flight Data Recorder with
Software
Foam
On-Board Electronics
Other Foam/Monocoat
In-Flight Data Recorder with
Software
Plane Take-Off Method
Plane-to-Tether
Connection
Man-powered winch
Prop with hand launch
Prop with winch launch
Propeller hand launch
Spool on Plane/ One Point
Propeller with hand launch
One Point/Ball and Socket
Joint
One Point/Ball and Socket Joint
One Point/Ball and Socket Joint
One Point Spool
Prop Location
2 Mid Wing Mounted Props
Nose
Middle
Middle (on top of fuselage)
Middle
Non-Destructively
Achieve Tether Tension
Spool on Board
Spring Behind Base
hand spool
hand spool
On-Board Spool
Offset Vertical circle
Offset vertical circle
Infinity shape
Parachute Deployment
Smooth Bottom
Smooth Bottom
Offset Vertical Circle
Land on Airframe
"Smooth"
Flight Path
Infinity
Protruding Rod/ Smooth
Non-Destructive Landing Bottom
10/2/2014
Yes
P15462
22
PUGH CHART
Selection Criteria
Simplicity/Effectiveness of Wing Design
Initial Cost
Replacement Part Cost
Weight
Durability
Ease of Manufacturing
Safe Landing
Develop Time
Repair Downtime
Simplicity of Take-Off Method
Tether Stress on Plane *
Tether Impulse Mitigation
Sum +'s
Sum -'s
Sum s's
Score
10/2/2014
Maginn
+
+
+
+
+
s
s
+
Zebert
+
+
+
+
+
s
s
Devin
+
+
+
+
s
+
Kennedy
+
+
+
+
+
s
s
s
Carl
+
+
+
+
+
s
s
+
6
4
2
2
5
5
2
0
5
6
1
-1
5
4
3
1
6
4
2
2
Datum (P14462 Bought Plane)
Datum
P15462
23
PUGH CHART
Selection Criteria
Simplicity/Effectiveness of Wing Design
Initial Cost
Replacement Part Cost
Weight
Durability
Ease of Manufacturing
Safe Landing
Develop Time
Repair Downtime
Simplicity of Take-Off Method
Tether Stress on Plane *
Tether Impulse Mitigation
Sum +'s
Sum -'s
Sum s's
k
10/2/2014
Maginn
+
+
+
+
+
s
-
Zebert
+
+
+
s
s
s
-
Devin
+
+
s
+
s
s
Kennedy
s
+
+
+
s
s
+
+
s
-
5
6
1
-1
3
6
3
-3
3
6
3
-3
5
3
4
2
Carl
Datum
0
Datum (P14462 Bought Plane)
+
+
+
+
s
s
4
6
2
-2
P15462
24
AGENDA
Background




Problem Statement
Customer Needs
Engineering Requirements
Week 3 action item review
System Analysis






Function Decomposition
Areas of Design
Solution Brainstorming
Selection Criteria
Concept Generation
Pugh Chart
 Final System Selection (5 min)
 Concept Feasibility (15 min)
 Updated Project Plan
 System Architecture
 Risk Assessment
10/2/2014
P15462
25
FINAL SYSTEM SELECTION
Areas of Design
Final System
Fuselage Design
Aerodynamically Optimized Rectangular Volume
Wing Design
Linear Taper, Fixed Angle of Attack, Dihedral, Flaps
Horizontal Tail Design
H-Shaped Tail
Fuselage Material
Foam with 3-D Printed Protective Electronic Housing
Wing/Tail Material
Carbon Fiber Strip Leading Edge, Foam with Coating
On-Board Electronics (Control Feedback) In-Flight Data Recorder with Software
Plane Take-Off Method
Propeller hand launch
Plane-to-Tether Connection
One Point/Ball and Socket Joint
Prop Location
Push Prop on back of fuselage
Non-Destructively Achieve Tether Tension Hand Spool
10/2/2014
Flight Path
Offset Vertical Circle
Non-Destructive Landing
Land on Airframe "Smooth"
P15462
26
FINAL SYSTEM SELECTION SKETCH
10/2/2014
P15462
27
CONCEPT FEASIBILITY - FLAP ANALYSIS
(1)
(2)
(3)
10/2/2014
P15462
28
CONCEPT FEASIBILITY - FLAP ANALYSIS
10/2/2014
P15462
29
CONCEPT FEASIBILITY - FLAP ANALYSIS
10/2/2014
P15462
30
CONCEPT FEASIBILITY-WINCH SYSTEM
 Means of takeoff since propeller alone is insufficient
 Pros:
 System has off board source of power
 Cons:
 Mechanical-Electrical system is expensive
 Alternative Method-Man Powered
 Pros:
 More affordable
 Cons:
 Is it feasible?
 Yes! The method is called a Towline Launch.
10/2/2014
P15462
31
FEASIBILITY STUDY: FOAM MATERIAL
Test Method
Density
Tensile Strength
Tensile Modulus
Elongation at Break
Compressive Strength
Compressive Modulus
Shear Strength
Shear Modulus
Max Shear Strain
Tear Strength
Flexural Strength
10/2/2014
Unit
kg/m3
MPa
MPa
%
MPa
MPa
MPa
MPa
%
kN/m
MPa
ROHACELL
71 Hero 110 Hero
75
110
4.10
6.30
123.00
189.00
9.50
9.90
1.10
2.50
48.00
83.00
1.30
2.30
28.00
50.00
7.20
7.20
-
200 Hero
205
12.30
389.00
10.80
7.10
180.00
5.20
109.00
7.20
-
EPP-20
20
0.26
15
0.31
1.74
0.21
Expanded Polypropylene
EPP-60 EPP-90 EPP-150 EPP-225
60
90
150
225
0.62
0.97
1.37
1.51
14
12
11
9
1.07
2.08
5.80
13.50
3.25
4.35
5.77
7.33
0.72
1.16
1.9
2.95
P15462
32
CONCEPT FEASIBILITY – FOLDING PROPELLER
Benefit:
• Less drag in unpowered flight
• More durable in nose first crash
• Interfaces with normal RC components
Feasibility Test Plan:
1. Test Flight with purchased glider
Due by:
1. Week 9
10/2/2014
P15462
33
CONCEPT FEASIBILITY – INFINITY FLIGHT PATH
Evaluate:
• Is this an easier flight path to maintain?
Feasibility Test Plan:
1. Test Flight with purchased glider
2. Test Flight with tethered purchased glider
Due by:
1. Week 9
*Image from Ampyx Power
10/2/2014
P15462
34
CONCEPT FEASIBILITY – DIHEDRAL ANALYSIS
 Definition of Dihedral:
 The angle between a wing and pitch axis
 Dihedral Effect Definition:
 Amount of roll moment produced per degree of sideslip
 Also influenced by wing sweep, vertical CG
 Benefits:
 Higher dihedral angles generate higher roll moments
 Stabilizes Plane against crosswinds
10/2/2014
P15462
35
CONCEPT FEASIBILITY – DIHEDRAL ANALYSIS
10/2/2014
P15462
36
CONCEPT FEASIBILITY – DIHEDRAL ANALYSIS
10/2/2014
P15462
37
CONCEPT FEASIBILITY – DIHEDRAL ANALYSIS
10/2/2014
P15462
38
AGENDA
Background




Underlying Mission
Problem Statement & Deliverables
Customer Needs & Engineering Requirements
Week 3 action item review
System Analysis









Functional Decomposition
Areas of Design
Solution Brainstorming
Selection Criteria
Concept Generation
Pugh Chart
Final System Selection
Concept Feasibility
Test Plan
 Updated Project Plan (2 min)
 System Architecture (2 min)
 Risk Assessment (2 min)
10/2/2014
P15462
39
Deliverables
Sytem Design
Post SDR
Subsystem Design
Deliverable Stage
Elevator Speech
Feasbility Posters
Invite SDR Attendees
Solidify SD (see below)
SDR Action Items
Test Plan
Peer Reviews
Critical Interfaces
Specs
Sub- Decomposition
Proof of Concept
Prelim DDR
Detailed Design & Componet Selection Update Test Plan
Edge Update
Invite DDR Attendies
10/2/2014
Week 1
Week 2
Week 3
Week 4
Week 5
1
1
1
1
Week 6
Week 7
Week 8
Week 9
RE
VI
EW
GN
DD
R
DE
SI
FI
NA
L
DE
TA
IL E
D
Week 10 Week 11 Week 12 Week 13 Week 14 Week 15
1
1
1
1
1
1
1
SU
SY
ST
EM
BS
YS
TE
M
DE
SI
SD
GN
ES
I
GN
RE
VI
EW
RE
VI
EW
UPDATED PROJECT PLAN
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
P15462
40
Fuselage Design
Wing Design
Tail Design
Preliminary Design
Final Design
Preliminary Design
Final Design
Preliminary Design
Final Design
Preliminary Design
Final Design
Preliminary Design
Final Design
Preliminary Design
Final Design
Preliminary Design
Final Design
1
1
1
1
1
1
Preliminary Design
Final Design
Preliminary Design
Final Design
Preliminary Design
Final Design
Preliminary Design
Final Design
Preliminary Design
Final Design
Preliminary Design
Final Design
1
1
1
1
UPDATED PROJECT PLAN
Aero and Structual Design
Propeller Design
Rudder Design
Structural Integrity
Control Surfaces
Electric Motor
Speed Controler
Linear Acuator Controls
Controls
Micro Controler Design
RC Design
Controls Algorithm
On Plane Hardware
Tether Material
Bridal System
Base System Integration
Kinematic Simulation (MATLAB)
Simulation Code
Aerodynamic Simulation (CFD)
Structual Analysis (ANSIS)
Maintenance Documentation
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Replaceable Parts List
Preliminary Design
Final Design
Preliminary Design
Final Design
Preliminary Design
Final Design
Preliminary Benchmark
Final Code
Preliminary Benchmark
Final Code
Preliminary Benchmark
Final Code
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SYSTEM ARCHITECTURE
Base Station
Glider Fuselage
Tether
Wings
Remote Control
Horizontal Tail
Vertical Tail
Propeller
Elevators
Rudders
Motor
On-Board
Feedback System
Ailerons
Flaps
On Board Control
Electronics
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RISK ASSESSMENT
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RISK ASSESSMENT (CONT.)
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SOURCES
 Feasibility Study: Foam Material
 http://www.rohacell.com/sites/dc/Downloadcenter/Evonik/Product/ROHACELL/productinformation/ROHACELL%20HERO%20Product%20Information.pdf
 http://www.sonoco.com/UserFiles/sonoco/Documents/Tegrant%20EPP%20Design%20G
uide%20April%202012.pdf
 http://en.wikipedia.org/wiki/Dihedral_(aeronautics)
 http://www.rc-airplane-world.com/image-files/rc-powered-glider-folding-prop.gif
 http://www.ampyxpower.com/
 http://www.amazon.com/
 http://www.google.com/makani/
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