Transcript National Aircraft Design-Build

National Aircraft
Design-Build-Fly
Competition
Team USYD
Overview
DESIGN
• Design process
• Design reasoning
• Problems solving
BUILD
FLY
• construction methods and
specifications
• Flight test
DESIGN
Design Process
Mission
Requirements
Rebuild
Conceptual
Design
Preliminary
Design
Detailed
design &
construction
Flight-testing
Computational
estimation
Computational
estimation
DESIGN
Critical Specifications
– 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
DESIGN
Desirable Specifications
–Highest possible wing loading
–Minimum take-off weight
–Minimum planform area
–Stable flight in all conditions
DESIGN
•Configuration studied
– Standard boxwing
– C-wing
– Closed box-wing
DESIGN
Computational Design

Solid Works – airframe design, weight and
balance

Desktop Aerodynamics – aerodynamic
prediction

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
DESIGN
INITIAL DESIGN
Aurora Mk I
•
•
•
Upper wing constructed from ply spar and
balsa ribs, surfaced with solar film
Foam core lower wing surfaced with balsa
sheet an solar film
V-tail made up from balsa sticks and fibreglassed to 12mm diameter carbon boom
DESIGN
INITIAL DESIGN
Aurora Mk I

Bulkheads fore and aft of payload made from
light ply

Firewall located and set at specific angle
relative to wings

Steel wire (3mm) folded and cut for
undercarriage
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
DESIGN
PROBLEM
Weak materials
SOLUTION
Tail boom replaced, aluminium plate
undercarriage
DESIGN
PROBLEM
Too large frontal area
SOLUTION
Rebuilt fuselage with more efficient payload
configuration
front
DESIGN
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
BUILD
REVISED DESIGN
Aurora Mk II
•
•
•
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
V-tail of slightly increased area was fibre-glassed
to a 7/8” diameter carbon tube
BUILD
REVISED DESIGN
Aurora Mk II

Wing/Body fillets sculpted from foam and fibreglassed for strength and durability
o
o

1.5 right side thrust and 1.5 down thrust were
built into the engine mount

4mm Aluminium undercarriage bought-off-shelf
and re-shaped to suit aircraft
BUILD
Specifications
Span: 1.4m
 Length:1.5
2
2
 Area: ~ 0.58m (900in )
 Mass:4 Kg
 Engine: Thunder Tiger 61 Pro (10c.c.)
 Servos: 5
 Channels: 5

FLY
Test flight
Pre-flight
•Ground Run Engine
•Adjust mixture
First Flight
•Zero payload flight
•Adjust trim for straight flight
FLY
Test flight
Second Flight
•Confirm trimming
Third Flight
•Confirm flight
characteristics with
payload
•Fuel consumption check
•Fly actual circuit
DESIGN - BUILD - FLY
Thanks to all our sponsors
For more details, please visit our web site:
http://www.aeromech.usyd.edu.au/RCplaneUSYD
Finally, thanks for your attention!!
Please feel free to ask any questions
about our
design