Team USYD National Aircraft Design-Build-Fly Competition

Overview Design process Design reasoning Problems solving construction methods and specifications Flight test DESIGN BUILD FLY

Design Process Preliminary Design Detailed design & construction Flight-testing Rebuild Conceptual Design Mission Requirements DESIGN 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

Configuration studied – Standard boxwing – C-wing – Closed box-wing

Computational Design Solid Works – airframe design, weight and balance Solid Works – airframe design, weight and balance Desktop Aerodynamics – aerodynamic prediction Desktop Aerodynamics – aerodynamic prediction Flight Sim – flight simulation and performance estimation Flight Sim – flight simulation and performance estimation 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 DESIGN Upper wing constructed from ply spar and balsa ribs, surfaced with solar film Upper wing constructed from ply spar and balsa ribs, surfaced with solar film Foam core lower wing surfaced with balsa sheet an solar film Foam core lower wing surfaced with balsa sheet an solar film V-tail made up from balsa sticks and fibre- glassed to 12mm diameter carbon boom V-tail made up from balsa sticks and fibre- glassed to 12mm diameter carbon boom Aurora Mk I DESIGN

INITIAL DESIGN Bulkheads fore and aft of payload made from light ply Bulkheads fore and aft of payload made from light ply Firewall located and set at specific angle relative to wings Firewall located and set at specific angle relative to wings Steel wire (3mm) folded and cut for undercarriage Steel wire (3mm) folded and cut for undercarriage Aurora 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 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, surrounded with balsa sheeting Wings constructed by a hot-wire cut foam core, surrounded with balsa sheeting Spar laminated from 2 pieces of 3mm birch ply wood with carbon fibre between them Spar laminated from 2 pieces of 3mm birch ply wood with carbon fibre between them V-tail of slightly increased area was fibre-glassed to a 7/8” diameter carbon tube V-tail of slightly increased area was fibre-glassed to a 7/8” diameter carbon tube REVISED DESIGN Aurora Mk II BUILD

Wing/Body fillets sculpted from foam and fibre- glassed for strength and durability Wing/Body fillets sculpted from foam and fibre- glassed for strength and durability 1.5 o right side thrust and 1.5 o down thrust were built into the engine mount 1.5 o right side thrust and 1.5 o down thrust were built into the engine mount 4mm Aluminium undercarriage bought-off-shelf and re-shaped to suit aircraft 4mm Aluminium undercarriage bought-off-shelf and re-shaped to suit aircraft REVISED DESIGN Aurora Mk II BUILD

Specifications Span: 1.4m Span: 1.4m Length:1.5 Length:1.5 Area: ~ 0.58m 2 (900in 2 ) Area: ~ 0.58m 2 (900in 2 ) Mass:4 Kg Mass:4 Kg Engine: Thunder Tiger 61 Pro (10c.c.) Engine: Thunder Tiger 61 Pro (10c.c.) Servos: 5 Servos: 5 Channels: 5 Channels: 5 BUILD

Test flight Pre-flight Ground Run Engine Adjust mixture First Flight Zero payload flight Adjust trim for straight flight FLY

Test flight FLY 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: Thanks to all our sponsors

Please feel free to ask any questions about our design Finally, thanks for your attention!!