Team Team USYDUSYD

National Aircraft National Aircraft Design-Build-Fly Design-Build-Fly

CompetitionCompetition

OverviewOverview

• Design process

• Design reasoning

• Problems solving

• construction methods and specifications

• Flight test

DESIGN

BUILD

FLY

Design ProcessDesign Process

Preliminary Design

Detailed design &

construction

Flight-testing

Rebuild

ConceptualDesign

Mission Requirements

DESIGN

Computational estimation

Computational estimation

– Blended wing/body aircraft

– 10 cc engine

– Remote controlled by human pilot

– Must carry payload of four Dick Smith Gravy packets (1.6kg total weight)

– Aspect ratio ≥ 2.0

– Project cost ≤ $1000

Critical Specifications

DESIGN

–Highest possible wing loading

–Minimum take-off weight

–Minimum planform area

–Stable flight in all conditions

Desirable Specifications

DESIGN

DESIGN

•Configuration studied

– Standard boxwing

– C-wing

– Closed box-wing

Computational DesignComputational Design Solid Works – airframe design, weight and Solid Works – airframe design, weight and

balancebalance

Desktop Aerodynamics – aerodynamic Desktop Aerodynamics – aerodynamic predictionprediction

Flight Sim – flight simulation and performance Flight Sim – flight simulation and performance estimationestimation

DESIGN

DESIGN

Box-wing configuration advantages

– Minimal planform area

– End caps improve wing strength

– Fully effective upper wing surface

– less run way area

DESIGN

V-tail selected

– Ease of construction

– Comparatively light

Tractor configuration

– Move C.G forward

– Propeller intake clear of wing interference

INITIAL DESIGNINITIAL DESIGN

• Upper wing constructed from ply spar and balsa Upper wing constructed from ply spar and balsa ribs, surfaced with solar filmribs, surfaced with solar film

• Foam core lower wing surfaced with balsa sheet Foam core lower wing surfaced with balsa sheet an solar filman solar film

• V-tail made up from balsa sticks and fibre-V-tail made up from balsa sticks and fibre-glassed to 12mm diameter carbon boomglassed to 12mm diameter carbon boom

Aurora Mk IAurora Mk I

DESIGN

INITIAL DESIGNINITIAL DESIGN

Bulkheads fore and aft of payload made from Bulkheads fore and aft of payload made from light plylight ply

Firewall located and set at specific angle Firewall located and set at specific angle relative to wingsrelative to wings

Steel wire (3mm) folded and cut for Steel wire (3mm) folded and cut for undercarriageundercarriage

Aurora Mk IAurora Mk I

DESIGN

BUILD

•Detailed design and construction

– Detailed calculations were completed

– Design continually modified as practical problems arose during construction

Aurora Mk I

BUILD

DESIGN

Problems Faced and FixedProblems Faced and Fixed

PROBLEM

Structural joints introduced weak points

SOLUTION

Structure rebuilt with 6:1 ratio joints

PROBLEM

Weak materials

SOLUTION

Tail boom replaced, aluminium plate

undercarriage

DESIGN

SOLUTION

Rebuilt fuselage with more efficient payload

configuration

DESIGN

PROBLEM

Too large frontal area

front

PROBLEM

Wing area too small

SOLUTION

Chord and span increased

DESIGN

PROBLEM

Fuselage not strong enough

SOLUTION

Fibre-glassed fuselage surfaces

DESIGN

PROBLEM

CG too far forward

SOLUTION

Moved controls to rear of fuselage

Added ballast to tail boom

DESIGN

• Wings constructed by a hot-wire cut foam core, Wings constructed by a hot-wire cut foam core, surrounded with balsa sheetingsurrounded with balsa sheeting

• Spar laminated from 2 pieces of 3mm birch ply wood Spar laminated from 2 pieces of 3mm birch ply wood with carbon fibre between themwith carbon fibre between them

• V-tail of slightly increased area was fibre-glassed to a V-tail of slightly increased area was fibre-glassed to a 7/8” diameter carbon tube 7/8” diameter carbon tube

REVISED DESIGNREVISED DESIGN

Aurora Mk IIAurora Mk II

BUILD

Wing/Body fillets sculpted from foam and fibre-Wing/Body fillets sculpted from foam and fibre-glassed for strength and durabilityglassed for strength and durability

1.51.5oo right side thrust and 1.5 right side thrust and 1.5oo

down thrust were down thrust were built into the engine mountbuilt into the engine mount

4mm Aluminium undercarriage bought-off-shelf 4mm Aluminium undercarriage bought-off-shelf and re-shaped to suit aircraftand re-shaped to suit aircraft

REVISED DESIGNREVISED DESIGN

Aurora Mk IIAurora Mk II

BUILD

SpecificationsSpecifications

Span: 1.4mSpan: 1.4mLength:1.5Length:1.5Area: ~ 0.58mArea: ~ 0.58m22

(900in (900in22))

Mass:4 KgMass:4 KgEngine: Thunder Tiger 61 Pro Engine: Thunder Tiger 61 Pro

(10c.c.)(10c.c.)Servos: 5Servos: 5Channels: 5Channels: 5

BUILD

Test flightTest flightPre-flight

•Ground Run Engine

•Adjust mixture

First Flight

•Zero payload flight

•Adjust trim for straight flight

FLY

Test flightTest flightFLY

Second Flight

•Confirm trimming

Third Flight

•Confirm flight characteristics with payload

•Fuel consumption check

•Fly actual circuit

DESIGN - BUILD - FLY

For more details, please visit our web site:

http://www.aeromech.usyd.edu.au/RCplaneUSYD

Thanks to all our sponsors

Please feel free to ask any questions about our

design

Finally, thanks for your attention!!