Multidisciplinary Senior Design I
P10232 System Design
Review
Unmanned Aerial Vehicle - Airframe C
Daniel Graves
James Reepmeyer
Brian Smaszcz
Alex Funiciello
Michael Hardbarger
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P10232 System Design Review
October 7, 2009
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Contents
P10232 Project Background
Project Summary........................................................................................................................................... 3
Key Project Goals .......................................................................................................................................... 3
P09232 Senior Design Project ....................................................................................................................... 3
P10232 Concept Generation
Aircraft Style.................................................................................................................................................. 4
Airframe (key features) ................................................................................................................................. 5
Airfoil ............................................................................................................................................................. 6
Landing Gear ................................................................................................................................................. 7
Propulsion ..................................................................................................................................................... 7
P10232 Concept Selection
Aircraft Selection........................................................................................................................................... 8
Airframe Selection ........................................................................................................................................ 8
Airfoil Selection ............................................................................................................................................. 9
Landing Gear Selection ................................................................................................................................. 9
Propulsion Selection ................................................................................................................................... 10
P10232 Final Concept
Selected Concept ........................................................................................................................................ 10
Important Links ........................................................................................................................................... 11
Bibliography ................................................................................................................................................ 11
P10232 System Design Review
October 7, 2009
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P10232 Project Background
Project Summary
The goal of the UAV Airframe C project is to provide an unmanned aerial platform used
for an aerial imaging system. The airframe must support the weight and interfaces for the
designed imaging system. The aircraft must be operated remotely and be a viable alternative to
current aerial imaging methods. This is a second generation airframe, expanding on the
previously laid ground work established by the P09232 UAV B Senior Design Project.
Key Project Goals
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Airframe must be able to carry a fifteen pound payload
Easy integration with measurement controls box and different aerial imaging systems
Ability to remotely control aircraft and activate payload
Ability for flight communication between aircraft and ground relay
Aircraft provides twenty minutes of flight time for local area photography
Aircraft has the potential to take off and land on site
Easy assembly and disassembly of the aircraft for transportation
P09232 Senior Design Project
The Unmanned Aerial Vehicle concept began with last years Senior Design team. The
design used was a traditional monoplane powered by a two-stroke gas engine, with a small
cambered flat bottom airfoil. Shortly after take-off the pilot lost control of the aircraft during a
banked turn. The plane proceeded to knife edge toward the ground, where the wings sheared
off shortly before impact. The failure was determined to be from the bending stress applied to
the wings during the banked turned. After analysis, it was concluded that the main fiberglass
spar used to support the wing was not selected properly to handle the flight loading.
Additionally, the high bend in the wing during flight inhibited the pilot’s control of the aircraft
by reducing the effectiveness of the control surfaces.
P10232 System Design Review
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P10232 Concept Generation
Aircraft Style
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Monoplane – Traditional single winged aircraft design
Biplane – Two stacked wings; same lift half the wingspan
More than 2 wings - Same idea as a biplane, but 3 or more wings
Delta Wing – Plane With a delta shaped wing design
Flying wing – A plane consisting only of a wing structure; ie. No fuselage
Dirigible – A lighter than air aircraft such as a blimp or hot air balloon
Rocket – A rocket propelled craft
Helicopter – VTOL style craft with horizontal blades and no fixed airfoils. Can have one
or more main rotors
Due to the variety of these options it was necessary to narrow down the overall direction of our
research prior to generating sub-concepts. After some initial research it was clear we would be
working with a fixed-wing aircraft (thus disqualifying the dirigible, rocket, and helicopter
options). For more on the selection process please see the Concept Selection section.
P10232 System Design Review
October 7, 2009
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Airframe (key features)
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Canards
Motor / Engine placement
o Pusher – motor in back of the plane, pushes plane through the air
o Puller – motor on the front of the aircraft
o Multiple Power Sources
 Wing Mounted – motors attached to wings instead of built into the
fuselage
 Twin Fuselage – one motor on the front of each fuselage
 Push and Pull – one motor on the front, one motor pushing from the back
Winglets – Small vertical stabilizers on the wing tips
Dual Fuselage – 2 fuselages running parallel, could hold cargo between them
Twin Boom – 2 extended booms connect the wing / fore-plane to the tail
Cambered (lifting) Tail
V-Tail – Two ‘slanted’ tails; fighter-jet style
H-Tail – Two vertical stabilizers / rudders on either end of the tail’s horizontal stabilizer
T-Tail – A traditional tail design but with the horizontal surface at the top of the vertical
stabilizer
Crucifix tail – Same as a T-tail but with the horizontal surface half-way up the vertical
stabilizer
Swept Wings – Wings swept back fighter-jet style (supersonic wing design)
Folding Wings – Wings that fold for transportation / storage
P10232 System Design Review
October 7, 2009
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Airfoil
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Thin wing – Airfoil with a low thickness to chord ratio.
Thick wing – Thickness to chord ratio of 12% or higher.
Symmetrical Wing – Symmetric about chord line
Cambered Wing – Curved airfoil to increase the nozzle and diffuser effects produced by
the wing.
Flat Bottomed Wing – A type of cambered airfoil with a flat, or nearly flat bottom
surface.
Elliptical Wing – Theoretically ideal wing design with an elliptical planform shape.
Rectangular Wing – Rectangular planform area.
Tapered Wing – Wing with a longer chord at the root than at the tip. Trapezoidal
planform shape.
Additional Lifting Surfaces (i.e. Canards) – Adds lift, allowing for a smaller main wing.
Wing Mounting (top / center / bottom)
o Top – Wing is above the fuselage, above the centre of gravity.
o Middle – Wing mounted to side of fuselage.
o Bottom – Wing sits under the fuselage, below the planes centre of gravity.
Swept Wings – Wing tips are behind the wing’s root, swept back, decreasing the speed of
the air across the wing.
Dihedral – Wing with a slight upward angle, with the tip higher than the wing root.
Anhedral – Wing with a downward angle, with the tip lower than the wing root.
P10232 System Design Review
October 7, 2009
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Landing Gear
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Number of Wheels
o 2 wheels
o 3 wheels
o More wheels
Non-Wheeled Landing Gear
o Skis – intended for use on snow
o Pontoons – for use on lakes (which are found near all nuclear power plants)
o Skids – skid plates on the underside of the plane in place of landing gear
Retractable Landing Gear
Wheel Placement
o Wing Mounted – anchored to the wings instead of the fuselage
o Tricycle layout – font wheel turns, 2 wheels in the back
o ‘Conventional’ layout – aka tail dragger, rear wheel turns, 2 wheels in front
Launch Assist
o Car-top – released from the top of a moving vehicle (requires highway)
o Catapult – instant launch from some sort of a stand. Crossbow design?
Brakes – reduced stopping distance
‘Leave-behind’ landing gear – plane would liftoff from a sled with wheels, leaving the
sled behind
Propulsion
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Power Source
o Electric Motor
 DC Brushless
 DC Brushed
 AC
o Fuel Powered
 2-Stroke (chainsaw / weed whacker)
 Glow / Nitro fuel
 Wankel
 4 –Stroke
 Diesel
o Rocket
 Rocket as main propulsion
 Rocket assisted launch
Exposed propeller
Inductive Fan
Multiple-Bladed propeller (>2 blades)
P10232 System Design Review
October 7, 2009
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P10232 Concept Selection
Aircraft Selection
Design
Cost (initial)
Cost (sustainable)
Controllability
Transport
Flight Time
Payload
Airspeed
Monoplane Bi-plane Delta Dirigible Helicopter Rocket Wing
0
-1
-1
1
-2
1
-2
0
-1
0
-1
0
1
1
0
0
0
-2
0
-2
0
0
-1
-1
-2
-2
-10
-2
0
1
-1
-2
1
1
-1
0
0
0
2
-1
-10
2
0
-1
1
-1
-1
-2
1
0
-1
-1
-2
-1
2
-1
Total
0
-4
-3
-7
-6
-19
-2
As shown in the concept selection matrix, the monoplane is considered the best option for
a successful design given the chosen criteria. After a critical analysis, the monoplane aircraft
design was the selected concept to move forward with into detailed design. The monoplane is the
most commonly used airframe design in any application, and to accommodate our short design
and build lead time, this will allow for a higher chance of success.
Airframe Selection
Stability
Design Difficulty
Weight
Controllability
Drag
Flight Envelope
Cost
Total
Cambered
0
0
0
0
0
0
0
0
H-Tail
1
-1
-1
1
1
0
-1
0
V-Tail
1
-2
-1
0
1
0
-1
-1
T-Tail
-1
-10
-1
1
0
1
-1
-11
Crucifix Tail
-1
-5
-1
1
0
1
-1
-6
As shown in the concept selection matrix, either a cambered tail or an H-tail would be
good concepts for down selection. After critical analysis, a cambered tail was selected as the
concept to move forward with due to its ease of design and implementation.
P10232 System Design Review
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Airfoil Selection
After a critical analysis of last year’s airfoil, the concept selected for the current airfoil is
an under-cambered thick airfoil. The more aggressive cambered airfoil will produce more lift,
decrease stall speed, and decrease the required chord to wingspan compared to the UAV B.
Final airfoil selection will be based on XFOIL analysis. The wing will be rectangular in shape due
to its ease of design and implementation. The planform area will be selected based on wing
loading.
Landing Gear Selection
Drag
Ground Control
Nose Over
Ground Loop
Cost
Load Handling
Risk of Prop. Damage
Cargo Protection
Required Environment
Total
Conventional
0
0
0
0
0
0
0
0
0
0
Tricycle
1
0
2
1
-1
-1
-1
-1
0
0
Skid Plates
1
-2
-1
-1
1
1
-1
-2
-1
-5
Pontoon/Floats
-2
-1
0
0
1
1
-1
0
-2
-4
Skis
0
0
0
0
-1
0
0
0
-2
-3
As shown by concept selection matrix, either the conventional landing gear system or a
tricycle style landing gear system would be appropriate for our system design. After a critical
analysis, the conventional style landing gear system was chosen as the concept to move forward
with because it provides a better angle of attack on the ground, creates less drag, and better
protects vital aircraft components in case of failure.
P10232 System Design Review
October 7, 2009
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Propulsion Selection
Initial Cost
Running Cost
Power
Weight
Design Flexibility
Fuel/Battery Consumption
Maximum Flight Time
Battery Fuel Weight
Vibration
Reliability
Total
Gasoline
0
0
0
0
0
0
0
0
0
0
0
Electric
-2
1
1
0
2
0
-1
0
1
2
4
As shown by the concept selection matrix, an electric motor propulsion system would be the best
concept for the given criteria. After a critical analysis, the electric propulsion system was selected to
move forward with into detailed design for its high reliability, ease of use, and design flexibility.
P10232 Selected System Design
Selected Concept
The selected system design for the P10232 project will be an electrically powered
monoplane with a standard cambered tail section. The airfoil will be under-cambered to
provide more lift and reduce the wingspan. The wing will be rectangular for its ease of design
and will be top-mounted to the airframe. A conventional landing gear system will be used to
assist in short take-off and for its low drag properties.
P10232 System Design Review
October 7, 2009
Important Links
P10232 Project Website - https://edge.rit.edu/content/P10232/public/Home
P09232 Project Website - https://edge.rit.edu/content/P09232/public/Home
Bibliography
Reyes, Carlos. Model Airplane Design Made Easy. Albuquerque: RCadvisor, 2009.
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