replicating the 1903 wright flyer

Introduction

Sir George CayleyConventional configuration

Otto LilienthalAirfoil data, first pilot

Alphonse PenaudRubber powered models

Octave ChanutePratt truss

Wright Brothers Control centric approach Wing warping for roll control First wind tunnel tests Adverse yaw Canard for pitch control

The Wright approach Wing warping tested on 1899 kite 1901 glider was a disappointment Wind tunnel testing leads to 1902

glider First powered flight, 1903

Problems in replication

InstabilityPitch, CG behind NPSpiral mode, Anhedral

ControlSmaller tail volumes

ConstructionalPractical limits due to scaling down

Strategy

Explore Airplane through literature

survey

Build Gliders

Glider Testing Propulsion

Prelim Report, Apr 2002

Final Design, Nov 2002

May 2002

Detailed Report, Dec 2002

Model Backup Model

Flight testing, June 2003 Done, Nov2003

Start

Strategy

Exploring a/cLiterature studyProposed solutions

Making glidersMaterial selectionPractical limits on fabricationImplementation of control mechanisms

Propulsion

Market survey forContra-rotating pushersBelts, pulleys and shaftsEngine

Test the setup

Glider Specifications1:12 scaled down modelWing Span 1.02 mLength 0.54mCanard area 6.3% of wing area, 0.0210 m2Rudder area 0.01 m2 Weight 0.15 KgBallast weight 0.040 KgWing loading 0.11 kg/m2

Glider

Glider Experience

Material selectionCentral carbon fibre box supporting

WingCanard and rudderEngine Landing gear

Central Box

Glider Experience

Material selectionBalsa wood used for

Wing ribsCanard and rudderVertical struts

Glider Experience

Monokote for wing coveringSlotted ribs for front sparJoints

Strut-spar pin joints replicatedPins lashed to spars and strutsRigging with twine thread

View of joints

Glider Experience

ControlsSteel wire for wing warpingFlexible joints in rear spar for wing warpingComplete canard moved for pitch control

(unlike original variable camber)

Weight estimationControls part

4 servos + Receiver+ Battery pack + Miscellaneous 160gm + 30gm + 120gm + 50gm =360 gm Propulsion part

Engine + Mount + Shafts, Belts, Pulleys + Fuel + Misc 335gm + 150gm+ 300gm+ 250gm+ 65gm =1100 gm

Landing gear = 150gm Structure part Carbon fiber composite + Balsa + Misc 450gm + 300gm + 250gm =1000gmTotal Maximum weight = 3 kgWing loading with this weight = 0.338 kg/m2

Thrust and Power Estimation

Max thrust required at min Cl/Cd = 12 NPower required at this Cl/Cd is 120 W

Engine of 250 W at 16000 rpmTwo 10X6 props at 8000 rpm give 15 N thrust

Thrust in lbs = 2.83x10-12

x RPM2 x D

4 x Cp x (P/29.92) x

(528/(460+T))

Propulsion

Electric motorLess weightNo starting problemsEase of maintenanceLarge battery weight (Can be used as ballast)

Lesser heating problems

Propulsion

Wankel IC engineHigh powerLess fuel weightCooling problems ?

Propulsion Belt pulley system Propeller shaft mounting replicated Contra-rotating propellers ?

6 cm

11 cm

9.3 cm

4 cm

25 cm

Side view transmission system

Front View

39.4 cm

23.5 cm

12 cm

5 cm

Unsolved problems Roll-yaw coupling ? Asymmetric yawing moment ? Pitch SAS using rate gyro? Tail and canard volumes ? Anhedral ? Landing ? Twisted belt drive ?

Cost EstimateCarbon fibre 2000

Balsa 500

Engines 8000

Belt, Pulleys, Bearings, Propeller

2900

Servos 4000

Miscellaneous 500

Total 17,900

Acknowledgements Prof. K. Sudhakar, IIT Bombay Dr. H. Arya, IIT Bombay