CONTENTS
| [INTRODUCTION.] | |
| PAGE | |
| §§ 1-5. The two classes of models—First requisite of a modelaeroplane. § 6. An art in itself. § 7. The leading principle | 1 |
| [CHAPTER I.] | |
| THE QUESTION OF WEIGHT. | |
| §§ 1-2. Its primary importance both in rubber and power-drivenmodels—Professor Langley's experiences. § 3. Theoreticalaspect of the question. § 4. Means whereby more weightcan be carried—How to obtain maximum strength withminimum weight. § 5. Heavy models versus light ones. | 4 |
| [CHAPTER II.] | |
| THE QUESTION OF RESISTANCE. | |
| § 1. The chief function of a model in the medium in which ittravels. § 2. Resistance considered as load percentage.§ 3. How made up. § 4. The shape of minimum resistance.§ 5. The case of rubber-driven models. § 6. The aerofoilsurface—Shape and material as affecting this question.§ 7. Skin friction—Its coefficient. § 8. Experimental proofsof its existence and importance. | 7 |
| [CHAPTER III.] | |
| THE QUESTION OF BALANCE. | |
| § 1. Automatic stability essential in a flying model. § 2.Theoretical researches on this question. §§ 3-6. A briefsummary of the chief conclusions arrived at—Remarks onand deductions from the same—Conditions for automaticstability. § 7. Theory and practice—Stringfellow—Pénaud—Tatin—Thequestion of Fins—Clarke's models—Somefurther considerations. § 8. Longitudinal stability.§ 9. Transverse stability. § 10. The dihedral angle.§ 11. Different forms of the latter. § 12. The "upturned"tip. § 13. The most efficient section. | 13 |
| [CHAPTER IV.] | |
| THE MOTIVE POWER. | |
| [Section I.]—Rubber Motors. | |
| § 1. Some experiments with rubber cord. § 2. Its extensionunder various weights. § 3. The laws of elongation(stretching)—Permanent set. § 4. Effects of elongationon its volume. § 5. "Stretched-twisted" rubber cord—Torqueexperiments with rubber strands of varying lengthand number. § 6. Results plotted as graphs—Deductions—Variousrelations—How to obtain the most efficientresults—Relations between the torque and the number ofstrands, and between the length of the strands and theirnumber. § 7. Analogy between rubber and "spring"motors—Where it fails to hold. § 8. Some further practicaldeductions. § 9. The number of revolutions thatcan be given to rubber motors. § 10. The maximumnumber of turns. § 11. "Lubricants" for rubber. § 12.Action of copper upon rubber. § 12A. Action of water, etc.§ 12B. How to preserve rubber. § 13. To test rubber.§ 14. The shape of the section. § 15. Size of section.§ 16. Geared rubber motors. § 17. The only system worthconsideration—Its practical difficulties. § 18. Its advantages. | 24 |
| [Section II.]—Other Forms of Motors. | |
| § 18A. Spring motors; their inferiority to rubber. § 18B. Themost efficient form of spring motor. § 18C. Compressed airmotors—A fascinating form of motor, "on paper." § 18D.The pneumatic drill—Application to a model aeroplane—Lengthof possible flight. § 18E. The pressure in motor-cartyres. § 19. Hargraves' compressed air models—The bestresults compared with rubber motors. § 20. The effect ofheating the air in its passage from the reservoir to themotor—The great gain in efficiency thereby attained—Liquidair—Practical drawbacks to the compressed-airmotor. § 21. Reducing valves—Lowest working pressure.§ 22. The inferiority of this motor compared with thesteam engine. § 22A. Tatin's air-compressed motor.§ 23. Steam engine—Steam engine model—ProfessorLangley's models—His experiment with various forms ofmotive power—Conclusions arrived at. § 24. His steamengine models—Difficulties and failures—and final success—The"boiler" the great difficulty—His model described.§ 25. The use of spirit or some very volatile hydrocarbonin the place of water. § 26. Steam turbines. § 27.Relation between "difficulty in construction" and the"size of the model." § 28. Experiments in France. § 29.Petrol motors.—But few successful models. § 30. Limitto size. § 31. Stanger's successful model described andillustrated. § 32. One-cylinder petrol motors. § 33. Electricmotors. | 39 |
| [CHAPTER V.] | |
| PROPELLERS OR SCREWS. | |
| § 1. The position of the propeller. § 2. The number of blades.§ 3. Fan versus propeller. § 4. The function of a propeller.§ 5. The pitch. § 6. Slip. § 7. Thrust. § 8. Pitch coefficient(or ratio). § 9. Diameter. § 10. Theoretical pitch.§ 11. Uniform pitch. § 12. How to ascertain the pitch ofa propeller. § 13. Hollow-faced blades. § 14. Blade area.§ 15. Rate of rotation. § 16. Shrouding. § 17. Generaldesign. § 18. The shape of the blades. § 19. Their generalcontour—Propeller design—How to design a propeller.§ 20. Experiments with propellers—Havilland's design forexperiments—The author experiments on dynamic thrustand model propellers generally. § 21. Fabric-coveredscrews. § 22. Experiments with twin propellers. § 23.The Fleming Williams propeller. § 24. Built-up v. twistedwooden propellers | 52 |
| [CHAPTER VI.] | |
| THE QUESTION OF SUSTENTATION. THE CENTRE OF PRESSURE. | |
| § 1. The centre of pressure—Automatic stability. § 2. Oscillations.§ 3. Arched surfaces and movements of the centreof pressure—Reversal. § 4. The centre of gravity and thecentre of pressure. § 5. Camber. § 6. Dipping front edge—Camber—Theangle of incidence and camber—Attitudeof the Wright machine. § 7. The most efficient form ofcamber. § 8. The instability of a deeply cambered surface.§ 9. Aspect ratio. § 10. Constant or varying camber.§ 11. Centre of pressure on arched surfaces | 78 |
| [CHAPTER VII.] | |
| MATERIALS FOR AEROPLANE CONSTRUCTION. | |
| § 1. The choice strictly limited. § 2. Bamboo. § 3. Ash—spruce—whitewood—poplar.§ 4. Steel. § 5. Umbrellasection steel. § 6. Steel wire. § 7. Silk. § 8. Aluminiumand magnalium. § 9. Alloys. § 10. Sheet ebonite—Vulcanizedfibre—Sheet celluloid—Mica. | 86 |
| [CHAPTER VIII.] | |
| HINTS ON THE BUILDING OF MODEL AEROPLANES. | |
| § 1. The chief difficulty to overcome. § 2. General design—Theprinciple of continuity. § 3. Simple monoplane. § 4.Importance of soldering. § 5. Things to avoid. § 6. Aerofoilof metal—wood—or fabric. § 7. Shape of aerofoil.§ 8. How to camber an aerocurve without ribs. § 9. Flexiblejoints. § 10. Single surfaces. § 11. The rod or tube carryingthe rubber motor. § 12. Position of the rubber.§ 13. The position of the centre of pressure. § 14. Elevatorsand tails. § 15. Skids versus wheels—Materials forskids. § 16. Shock absorbers, how to attach—Relationbetween the "gap" and the "chord" | 93 |
| [CHAPTER IX.] | |
| THE STEERING OF THE MODEL. | |
| § 1. A problem of great difficulty—Effects of propeller torque.§ 2. How obviated. § 3. The two-propeller solution—Thereason why it is only a partial success. § 4. The speedsolution. § 5. Vertical fins. § 6. Balancing tips or ailerons.§ 7. Weighting. § 8. By means of transversely cantingthe elevator. § 9. The necessity for some form of "keel". | 105 |
| [CHAPTER X.] | |
| THE LAUNCHING OF THE MODEL. | |
| § 1. The direction in which to launch them. § 2. The velocity—woodenaerofoils and fabric-covered aerofoils—Poynter'slaunching apparatus. § 3. The launching of very lightmodels. § 4. Large size and power-driven models. § 5.Models designed to rise from the ground—Paulhan's prizemodel. § 6. The setting of the elevator. § 7. The mostsuitable propeller for this form of model. § 8. ProfessorKress' method of launching. § 9. How to launch a twinscrew model. § 10. A prior revolution of the propellers.§ 11. The best angle at which to launch a model | 109 |
| [CHAPTER XI.] | |
| HELICOPTER MODELS. | |
| § 1. Models quite easy to make. § 2. Sir George Cayley's helicoptermodel. § 3. Phillips' successful power-driven model.§ 4. Toy helicopters. § 5. Incorrect and correct way ofarranging the propellers. § 6. Fabric covered screws. § 7.A design to obviate weight. § 8. The question of a fin orkeel. | 113 |
| [CHAPTER XII.] | |
| EXPERIMENTAL RECORDS | 116 |
| [CHAPTER XIII.] | |
| MODEL FLYING COMPETITIONS. | |
| § 1. A few general details concerning such. § 2. Aero ModelsAssociation's classification, etc. § 3. Various points to bekept in mind when competing. | 119 |
| [CHAPTER XIV.] | |
| USEFUL NOTES, TABLES, FORMULÆ, ETC. | |
| § 1. Comparative velocities. § 2. Conversions. § 3. Areas ofvarious shaped surfaces. § 4. French and English measures.§ 5. Useful data. § 6. Table of equivalent inclinations.§ 7. Table of skin friction. § 8. Table I. (metals). § 9.Table II. (wind pressures). § 10. Wind pressure on variousshaped bodies. § 11. Table III. (lift and drift) on acambered surface. § 12. Table IV. (lift and drift)—On aplane aerofoil—Deductions. § 13. Table V. (timber). § 14.Formula connecting weight lifted and velocity. § 15.Formula connecting models of similar design but differentweights. § 16. Formula connecting power and speed. § 17.Propeller thrust. § 18. To determine experimentally thestatic thrust of a propeller. § 19. Horse-power and thenumber of revolutions. § 20. To compare one model withanother. § 21. Work done by a clockwork spring motor.§ 22. To ascertain the horse-power of a rubber motor.§ 23. Foot-pounds of energy in a given weight of rubber—Experimentaldetermination of. § 24. Theoretical lengthof flight. § 25. To test different motors. § 26. Efficiencyof a model. § 27. Efficiency of design. § 28. Naphthaengines. § 29. Horse-power and weight of model petrolmotors. § 30. Formula for rating the same. § 30A. Relationbetween static thrust of propeller and total weight ofmodel. § 31. How to find the height of an inaccessibleobject (kite, balloon, etc.). § 32. Formula for I.H.P. ofmodel steam engines. | 125 |
| [APPENDIX A.] | |
| Some models which have won medals atopen competitions | 143 |
GLOSSARY OF TERMS USED IN
MODEL AEROPLANING.
Aeroplane. A motor-driven flying machine which relies upon surfaces for its support in the air.
Monoplane (single). An aeroplane with one pair of outstretched wings.
Aerofoil. These outstretched wings are often called aerofoil surfaces. One pair of wings forming one aerofoil surface.