Aerobatics E-Book

Neil Williams

• Herausgeber: Crowood
• Kategorie: Lebensstil
• Sprache: Englisch

Seitenzahl: 358

Veröffentlichungsjahr: 2014

Beschreibung

Acclaimed worldwide as the most detailed and knowledgeable text about Aerobatics. This book takes the pilot from the basic manoeuvres step by step through to the exacting standards required at World Championship level. Neil Williams has been British Aerobatics Champion 12 times.

Leseprobe

Aerobatics

NEIL WILLIAMS

Illustrated by L. R. Williams

Airlife

First published in Great Britain in 1975by Airlife Publishing Ltdan imprint ofThe Crowood Press LtdRamsbury, MarlboroughWiltshire SN8 2HR

www.crowood.com

This e-book first published in 2014

Paperback edition 2003

This impression 2009

© Neil Williams 1975

All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information storage and retrieval system, without permission in writing from the publishers.

British Library Cataloguing-in-Publication Data

A catalogue record for this book is available from the British Library.

ISBN 978 1 84797 782 3

Foreword by

Air Commodore J. de M. Severne

MVO OBE AFC

Commandant, Central Flying School

Royal Air Force

There are several reasons for wanting to do aerobatics, but perhaps the most compelling are that they are challenging, exciting and above all enjoyable. Every pilot, whether he be amateur or professional, commercial or military, should have some degree of proficiency in aerobatics if, as the author says, he is to know the limits of his aeroplane and know how to get the best out of it.

I believe this is the first time that a comprehensive book on the art of aerobatics – and it is an art – has ever been written in any language and I am sure it will become a standard work for many years to come. Not only will it benefit the aspiring champion and all those who wish to improve their skill, at whatever level, but it will also benefit those who simply enjoy watching; just as a good hi-fi set and a degree of appreciation greatly enhance the enjoyment of listening to music, so will this book enable us all to appreciate the thought, effort and skill that goes into a competition sequence or a demonstration at an air display.

Few people are as well qualified to write this book as Neil Williams. He is a very experienced pilot in the broadest sense having flown over 150 types of aircraft, ranging from the 1912 Blackburn Monoplane to present-day military jets and modern airliner?. He is also an experienced civil and military test pilot who knows better than anyone the importance of the cautious approach to flying. It is significant that, throughout his career, he has always retained the sheer joy of flying and anyone who has seen him perform in his Pitts Special will know that he is the ideal man to discuss aerobatics.

If you enjoy this book half as much as I did, you won’t be able to put it down, so – read on!

Contents

        Introduction

  1    Why?

  2    The raw material

  3    Preparation

  4    Pre-aerobatic training

  5    The basic manoeuvres - the loop

  6    The basic manoeuvres - the roll.

  7    The basic manoeuvres - the stall turn.

  8    Basic combination manoeuvres

  9    Basic sequences

10    Inverted flying and turns

11    Acceleration

12    Limitations

13    Developing the roll

14    Developing the loop

15    Outside manoeuvres

16    Aresti explained

17    Fractions of flicks

18    The vertical roll

19    Advanced spinning and falling leaf

20    Wind and its effects

21    Advanced sequence construction

22    What is a lomcovàk?

23    Tail slides and torque rolls

24    Knife flight and bridges

25    Aerobatics unlimited

26    Training methods

27    Low level aerobatics and display flying

28    American manoeuvres and terms

29    Aeroplanes for aerobatics

30    At the competition

Aerobatics

Introduction

This is a book, by a pilot, for pilots. It has been long in the planning, and longer still in the execution, because there have been questions which are also asked by the pilot about to try his hand for the first time at the sport of aerobatics - “how do I begin?” or “where shall I start?”

When one knows a great deal about a subject, or when one knows very little, these problems arise.

Nearly twenty-five years ago, when I learned to fly, I asked these questions, but then there was no answer. A few pilots knew the absolute mastery of an aeroplane which is the reward of the aerobatic pilot, but very few would, or could, impart their knowledge. It was a closed shop.

Indeed, at that time aerobatics were the righteous preserve of the flying instructor, not something to be tampered with by an inexperienced club pilot. Well might those old pilots been proud of their prowess, long before the advent of Aresti, when exponents of the art such as Dusty Miller, of EFTS fame, could do things with a Tiger Moth that would make any modern pilot’s hair stand on end. But now they are gone, and their skill with them. As a student pilot, I found myself in the same quandary as many students today; I desperately wanted to learn, but nobody would teach. I decided to teach myself.

So it was that sometimes, in those far off days, a Tiger Moth could occasionally be seen, at a great height over the coastal plain of South Wales, looping, stall-turning, spinning; cautiously at first, then with slowly increasing confidence.

Slow rolls took longer to learn; I had no instructor, no critic to watch me, nobody who even knew what I was doing: the official duty was usually “map reading exercises”.

It was a foolish and painstaking way to learn, and many times it was only the strength and drag of the Tiger that saved me from more than embarrassment as I fell out of slow rolls, time and time again.

Finally I learned the secret of how to roll a Tiger accurately – but I had paid for it. This one manoeuvre had taken two and a half years to perfect! Gradually I added to my repertoire, and little by little came lower, but it was not until ten years after I had started that I finally came down as low as a thousand feet. In learning, I made nearly every mistake in the book, but I was lucky; and I tried to learn from them.

Now, nearly twenty-five years after those first struggling figures, I have learned something about this king of sports - the art of aerobatics. And now the boot is on the other foot, because in increasing numbers I am approached by pilots of different levels of experience, all asking the same question - will I teach them aerobatics?

Usually they want only a few flights, maybe up to five hours, and they cannot grasp the impossibility of trying to impart the knowledge of nearly a quarter of a century into so short a time. Even if I could instruct at that pace, they could not absorb it. A few dedicated pilots have accepted this, and are now beginning to see the results of their efforts reflected in their position in national and international competition, but these are the people who have made considerable sacrifices of time and money over a period of years.

For some pilots, aerobatic flying seems to be a short cut to the glamour and public acclaim of display flying, but this, for the competition pilot can be a dead end. He may well bask in the applause of the crowd, but a discerning observer will note the beginning of a deteriorating performance, unless at the same time one whets the edge of control with constant practice and actual competition. It is a hard existence; if it were easy everyone could do it. But in spite of this, there is actually no magic formula – it is simply a question of hard work. Perhaps the most difficult thing to acquire in the early stages is the knowledge of what is required, and the question of how and where to start. But no matter how much information is imparted by the written word, good instruction will always improve on theory. The aim of this book is to answer all the questions I wanted to ask when I started learning aerobatics, and to describe manoeuvres and sequences, basic and advanced. It is no substitute for good airborne instruction or even solo practice at a safe altitude. But it will tell you the best way of going about it, and the areas to avoid. In describing my own mistakes it will help you to progress more quickly, and more safely.

It all takes time, as does anything that is worth doing well. The tutor of Alexander the Great once remarked to his complaining pupil “There is no royal road to geometry.” Neither is there a short cut to aerobatic flying.

1

Why?

For centuries, man watched with envy the flight of birds, and dreamed of being able to match their skill and grace. The unsteady, shaky flight of the earliest aircraft was a far cry from the effortless soaring of the birds, and far from being satisfied with their efforts, men still yearned for the same ease of control and manoeuvrability which persistently evaded their grasp.

Better aircraft with more reliable engines began to appear, and the pilots of these machines vied with one another at early flying demonstrations to prove the superiority of their craft. It was during such a meeting that the Frenchman Pegoud performed the first aerobatic manoeuvre when he looped his Bleriot. The First World War was responsible for a very rapid advance in the design of aircraft, and very soon it was found that the pilot with the more powerful and manoeuvrable aircraft would emerge victorious in air combat.

M. Adolphe Pegoud on his looping Bleriot Monoplane

At this time, pilots began to realise that the control, strength and power of the aeroplane could be made to conform to their will to produce an intricate pattern in the sky, giving them a sense of freedom that no man before them had ever enjoyed. They were flying with the ease of birds and the sport of aerobatics had been born.

Aerobatics soon became synonymous with stunt flying, unfortunately, and for many years was regarded as the wicked lady of aviation. Yet the lure of the pure aerial ballet remained and between the wars only a few timid pilots could resist the temptation to learn the art of aerobatics. At that time, the biplane reigned supreme, and unfortunate is the man who has not stopped to watch a tiny silver biplane high among the cumulus clouds, the sole performer on a stage of infinite breadth and indescribable grandeur. The roar of the engine is muted to a far-off drone, no louder than a bee in the summer sky, and the sun glints and sparkles on the wings and cowlings as the aircraft loops and rolls with easy grace.

How many thousands of unknown spectators are the audience to this performance? The pilot, oblivious to the envious watcher, sits behind a small windscreen, his hands and feet resting lightly on the controls. The air is crisp and clear and he is alone in the sky.

The sound is very different here, the muted drone is a deep-throated snarl that blends with the roar of the slipstream and the howl of the bracing wires. To the pilot this is no mere machine, but a living creature, quivering with life, eager to respond to every pressure on the controls. The slipstream thunders around the cockpit, tugging mischievously at the pilot’s leather helmet and goggles. The propellor is a whirling disc, shimmering in the sun, and the instruments, trembling, tell their own stories – airspeed, altitude, engine rpm, oil pressure and temperature, fuel contents, sideslip. The pilot scans these at a glance, not really studying any one of them, but knowing that all is as it should be.

A slight back pressure on the stick and the aircraft soars upward, stick and rudder smoothly co-ordinated, and the little biplane is poised on a wingtip, the slipstream dying to a sigh while the engine noise becomes harsh and strident. Now the nose is dropping and the slipstream rises to a shrieking crescendo, drowning even the engine’s blare. The controls become heavy as the airspeed indicator shows the speed rising towards the maximum. The pilot’s movements are quite small now, for the aircraft responds very quickly to the slightest pressure.

Slowly the nose comes up and as the aircraft comes out of the dive, the pilot presses back harder on the stick. The machine arcs upward, the flying wires tight with strain, while the landing wires, relaxed, vibrate until they are blurred. The “g” forces press him down into his seat and his muscles are tensed as he combats the rising acceleration. Now the climb is vertical and the pilot looks up and back for the horizon to appear. The pull force is easier now and as the top wing comes into line with the horizon, the pilot eases the stick forward. With hardly a pause, the stick is pressed to the right and the horizon revolves slowly. A touch of right rudder and the roll off the top is complete. Another wingover, this time soaring above the peak of a snow white towering cumulus cloud, before diving again for a lazy, flowing, slow roll, so beautifully controlled and easy that the watchers on the ground are unaware of the months of practice to achieve it.

Wing-Over

For most pilots, the sense of achievement and freedom is sufficient reward in itself – coupled with the knowledge that a pilot skilled in aerobatics is a much more accomplished pilot, since he knows the limits of his aeroplane and how to get the best out of it. The art of aerobatics brings confidence and increases skill, touch, and an understanding of the finer points of aerodynamics – in a way that cannot be accomplished in any lecture room.

It is inevitable in such an advanced form of expression that those who excel will become interested in competition, for this is one way of determining just how good a pilot really is.

Competition flying is not a relaxing business, though, and many good aerobatic pilots prefer the enjoyment of flying for their own recreation rather than undergoing the pressures of contest flying.

For those who do enter competitions, there is all the colour and drama that anyone could wish for. At international meetings, pilots from fifteen to twenty countries arrive at the contest airfield with brilliantly painted machines.

Then comes the most enjoyable part; the training period, during which each competitor is allowed two practice flights over the airfield. Pilots walk up and down the lines of aircraft, renewing old acquaintances and making new ones. Occasionally one finds an aeroplane with a diagram of its pilot’s aerobatic sequence attached to the panel and these are studied with interest. Some pilots with a strong sense of humour have been known to leave impossible sequences fixed to their aircraft and then to retire to a safe distance and watch the expression on their rivals’ faces.

The waiting is the worst, especially for the first round of the competition. Many pilots at this stage ignore their rivals’ performances and try to relax in their tents. Once in the aircraft, with the engine running, the initial nervousness disappears and one becomes impatient to get airborne. Preflight checks are usually carried out about three times each, because there must be no mistakes at this stage.

The starter’s flag drops and we start the stopwatch. All nervousness has disappeared as we open the throttle for take-off. The climb is initially straight ahead, as the pre-aerobatic checks are carried out (one never sees a pilot showing off at a world championship event).

The climb pattern has been planned to put us at the correct height directly over the start point, marked by a cross on the ground. During the climb, we check to see if our four datum points are clearly visible on each end of each axis and we monitor our engine instruments.

We rock the wings – the signal that we are about to begin – and roll the aircraft into a dive straight above the main axis. Now we are almost over the centre of the field and can no longer see the axes. We think of those competitors who have a vision panel in the floor and resolve to modify our own aircraft. But there is no time now to think of that, we have full power selected. We make small and instinctive corrections for turbulence and after a quick check of the airspeed, the stick comes back hard and the aircraft shudders as the needle on the accelerometer peaks on the red line. The pitch is checked sharply as the aircraft hits the vertical and full right aileron is applied. The wingtips race around the horizon, which is blurred because of the high rate of roll. The datum points flash past — one, two, three, four — and the roll is checked exactly on the last one. The vertical climb is held until the speed is no longer reading and the power is cut right back to idle. As the aircraft starts to slide backwards, the stick is eased back a little and rudder and stick are then held as firmly as possible. The controls are trying to snatch over, and we hang on grimly. Suddenly the nose goes down hard in a vicious hammer-head stall; as it does, we apply full power, and as the engine roars back to life, we hit hard rudder and forward stick for a vertical diving outside flickroll. We cut the power again and recover after one turn, checking that our flight path is exactly vertical. We also note that we are exactly over the intersection of the axes; perhaps we don’t need that clear vision panel after all!

So the sequence goes on for up to thirty manoeuvres of exacting precision flying, so different in concept from the antics of the little biplane high above the clouds, but equally as rewarding.

The combination of the two styles is probably the most exacting and difficult to achieve, and is the ultimate in aerial ballet. The effort is great, the concentration intense, the workload high, and the rewards infinite.

With each step, new vistas of knowledge and skill open up ahead; there is no place here for the man who professes to know it all. Here, with every freedom in space and time, man can satisfy his inner cravings, where science and art are blended into one, and where at last he can achieve mastery in the air.

2

The raw material

“If God had meant man to fly, he would have given us wings”. So preached Bishop Wright, father of Orville and Wilbur, before his sons achieved the success that was to change the face of the world.

Yet, in a sense, Bishop Wright was correct, because the air is not man’s natural element; he must always be an intruder. Pilots are made, not born. The “natural” pilot is really a myth, boosted by boy’s adventure stories, and later, by the T.V. and film industry. What is really meant is that those individuals who have good physical and mental co-ordination will learn more quickly; and the RAF’s accent on sport in the selection and training of pilots is indicative of this.

But there is no question of “supermen” here. Almost anyone can learn how to fly an aeroplane; indeed, at the time of writing, about 100,000 licences have been issued in this country. Why is it, then, that only a handful of pilots regularly fly advanced aerobatics.?

The primary fault lies in the bar or crewroom of the average flying club. It only requires a discussion to be started about stalling and spinning for the various “pundits” to go into nauseating detail about that horrific occasion when they were introduced to these exercises; and the detail will have lost nothing by repetition over the years. Student pilots will be alarmed by such stories, and a barrier will be raised in their minds which can effectively prohibit them from thinking and acting coherently when they eventually encounter that terror of the air, the spin.

I have trained pilots such as these, and others who have never been told that aerobatics are difficult, or dangerous, or make one feel unwell, and the second group learn much more quickly, and make better aerobatic pilots. I suppose it is impossible to suppress tales of fright and airsickness, because there seems to be some kind of morbid pleasure in the telling. It would appear to be “manly” to force oneself to overcome real fear, and to continue to try to keep up appearances, when in fact the last thing a student wants to do is to step into an aeroplane.

In the first place there is nothing wrong with being afraid of flying; lots of people who are extremely courageous in other spheres are not able to master their concern here. I am afraid of potholing — so I don’t do it. In the same way, if there is a genuine fear of flying, the best thing to do is to find some other occupation. It is all very well proving how brave you are by continuing, but this can only be to the detriment of your instructor and other pilots. A frightened pilot will never fly as accurately or safely as he would want to. In any case, flying is supposed to be fun, so why pay a lot of money to be frightened?

In some cases, a student may have been frightened by being exposed to aerobatics poorly performed, at an unsafe altitude; and this can leave an indelible mark on his future piloting career. This is a different kind of fear, and this can be overcome by patient explanation, and a gentle introduction into well flown aerobatics at a safe height.

Mention aerobatics and the first reaction will be the possibility of airsickness. I am often asked after an aerobatic display if my stomach is still in good working order — and this question has even been asked by Air Force personnel; so how can one expect the average student or private pilot to react differently? It is certain that with regard to airsickness the biggest problem lies in the mind. One can experience nausea without actually moving one’s body; the result of movement is the disorientation caused by the semi-circular canals in the ear. The physical result of these is the same and is directly traced to the brain, which also receives stimulus from the amount of pressure being exerted on the body, and the distribution of this pressure. For example, if one rides on a roller coaster at the seaside, when the car plunges down an incline, one’s “stomach is left behind.” But we know that the stomach does not move; so what causes the sensation? It is the result of change of pressure distribution from the seat to the floor, which transmits a message to the brain which says “I am falling”. If one is now strapped securely to that same seat, and if one’s feet are held clear of the floor, the sensation is no longer present. There is a jolt against the belt, and that is all. Now we have a parallel with a common problem in flying; either encountering turbulence or entering a dive suddenly. Merely tighten your seat belt and don’t jam your feet hard on the floor, and the sinking sensation will disappear.

This same sensation is often present in a poorly demonstrated stalling exercise and is one of the reasons for the dislike of the exercise. It can of course be greatly reduced by the use of the above technique, but it can be eliminated altogether by a little thought on the part of the instructor.

For some reason, when the stall is approached, the nose is raised to an incredible angle, and before the stall proper is reached, the instructor heaves back on the stick and the aircraft rears up, everything goes quiet, and then gravity really takes over as the misused aircraft carries out the inevitable “hammerhead” stall. Down goes the nose with a bang, and another frightened and disillusioned student joins the ranks of the straight and level brigade.

There is absolutely no reason why this technique should be adopted; it doesn’t teach the student what the accidental stall is really like, and if the aircraft won’t stall properly then he should be shown on an aircraft that will, instead of having the wits scared out of him. I have had the task on many occasions of coaxing students into being shown a real stall after just such an experience. Invariably their reaction was “is that all it is?” And then they try it themselves; no more fears, no more “queasiness”; and more important, now they are more in command of the aeroplane.

Now, with the hurdle of stalling behind, the spinning exercise can be considered in a different light. Again with the stomach in mind, many students deliberately refrain from eating before spinning; the worst thing one can do. With an empty stomach grumbling away the student is not allowed to forget it, so that he is already psychologically prepared for disaster in that area. Also his blood sugar level will be lowered, and he will not have his normal workload and concentration capacity. During the recovery from the spin, the student will encounter positive acceleration in the order of 3g as the aircraft levels out. With an empty stomach this may cause him to “grey-out”, especially if he is not used to g. Again this may cause him sufficient unpleasantness to deter him from wishing to repeat the experience, During hard training for aerobatics, if I find my g threshold reducing, I stop for a good meal, and allow an hour for the results to be effective. My g tolerance will then have gone up by at least 2. Perhaps the biggest fear in flying is that of falling; after all, the effects of gravity are dramatically imprinted on us all from a very early age. These fears are perhaps most noticeable in an open cockpit, where one feels much more in contact with the elements, and where one instinctively leans “against” the turn when the aeroplane banks. The best way to overcome this is in the knowledge that this is a perfectly natural reaction – this is, after all, not our natural element. If we consider that the forces involved can be likened to taking a corner on a motorcycle, it becomes apparent that we will not feel any strange effects if we lean with the machine. We will find, as we progress, that we can carry out simple aerobatic manoeuvres without feeling the need for restraining straps; indeed I have barrel-rolled aircraft without the crew knowing it!

Leaning with the machine

One needs to understand something of the construction of the aeroplane before one can feel any confidence in it; after all, it looks so frail compared, for example, to the family car. Just consider, though, what would happen to the family car if it were subjected to six times its normal weight!

Aerobatic aeroplanes, on the other hand, are regularly subjected to these forces, and do not exhibit any particular signs of stress. However, aerobatic aeroplanes tend to fly upside down, and if stalling and spinning caused problems, imagine the consternation produced by the thought of flying inverted, especially in an open cockpit aeroplane! What, one asks innocently, is the problem? Inevitably, it is the possible danger of falling out, and any assurances to the contrary will be met with the same scepticism that I would demonstrate, were I to be subjected to persuasion that potholing is safe! However, let us look at the facts. The difference between an open and closed cockpit, apart from the draught, is academic in that 1/16" perspex would be highly unlikely to retard one’s progress. The only real difference is psychological. Current cockpit design provides for two separate harnesses, the primary one attached to the seat, and the secondary to the airframe itself. The primary harness consists of five straps, including the all-important negative g strap, and these are secured by a simple clip, rather than a quick release box. At least one can see what is holding oneself in, and that it is properly done up. As insurance against the extremely unlikely event of the seat becoming detached, the secondary harness goes around both pilot and seat. This results in a total of seven restraining straps, each one capable of supporting about 3,000 lbs. Some years ago, as the result of a miscalculation, I had a rather abrupt encounter with terra firma, whilst attached to the aeroplane as described above. The result was a totally destroyed aeroplane, and a bruised, but intact, pilot. All seven straps had held, and although I parted company with the aeroplane after it hit the ground, I was still firmly strapped into the seat, and the secondary harness was still bolted onto what was left of the bottom longerons. A harness of this type will guarantee that one remains firmly attached to the aeroplane, no matter what.

Typical aerobatic harness : ZLIN 526

These, then, are some of the initial problems encountered during the approach to aerobatics.

Before embarking on a course of aerobatic instruction, ask yourself why you want to do it. It will mean a considerable sacrifice, of time and money, at the least, and there will be no guarantee of results. If you see yourself as another Cantacuzene, better forget it, the law of averages exists, and he died in bed! If it’s a question of impressing one’s girl friend, by the time you are able to, the odds are she will have become fed up and moved on.

There is no reason for flying aerobatics; if you really want to, without knowing exactly why, and you are prepared to really work and to explore this exciting sport, you’ve been bitten. It is rather like a drug, the more you indulge, the greater is the attraction. But unlike a drug, there are no grey areas, only black or white. A famous Czechoslovakian pilot once said “You cannot lie to yourself in aerobatics” — here self discipline must reign supreme. Perhaps the most important thing that you will learn is the truth — pleasant or otherwise — about yourself.

3

Preparation

“How will I react”? is the question that is often asked by students about to embark upon their first aerobatic flight, for they cannot help comparing the thought of performing aerobatics with childhood memories of devilish fairground contrivances. Of all the hurdles they will have to cross, this is the first, and the hardest. A great many of their acquaintances will draw a depressing picture of the terrors in store; although a close investigation will reveal that they have little or no experience of aerobatic flying. This sport is the most misunderstood facet of aviation, so with this fact borne firmly in mind, the student should try to ignore the advice and comments of those not qualified to speak. It is a sad reflection on the state of the aeronautical community that pilots who should know better are guilty of prejudice in the field of aerobatics. Indeed, some may have had the uncomfortable experience of being subjected to aerobatics by someone whose enthusiasm exceeded their ability, and perhaps with a slack safety harness into the bargain!

If their introduction to the sport had been conducted in a more responsible manner, many more good pilots would have had the opportunity to increase their skills, and the sport would have been advanced by many years..

Initial doubts about one’s reaction to unaccustomed stresses are easily resolved: on the first introduction to aerobatics the figures will be simple and the forces will not be excessive. To ensure that this is so one will have asked for a demonstration by a skilled and reliable pilot, who will at all times concern himself with the well being of his passenger. He knows that his potential student will be rather wound up, and he will limit both the duration and the content of the sortie to suit. In any case, fifteen minutes is quite long enough the first time up, since the aim is to provide an enjoyable experience. Let there be no worries about the physical forces of acceleration at this stage, since if one is fit enough to hold a pilots licence one can certainly accept the relatively modest accelerations involved, although when first encountered they will feel fairly high. The maximum negative g encountered will be one’s own weight on the straps, since the instructor will not show anything more advanced than a slow roll on this flight. One will note that the straps restrain the body perfectly. In spite of the fact that the instructor adjusted the harness, the student will inevitably worry about his security, and this is quite a normal sensation at this stage. If one is concerned about this level of negative g, one can produce a worse situation on the ground by doing a handstand. In the aeroplane one assumes a sitting position, therefore there is less pressure on the chest and head. This is not in the least dangerous to any normal person.

With the demonstration flight behind us, it is now possible to look forward to being able to fly aerobatics oneself.

The first problem is to decide on the type of aeroplane to be used, a decision which will not arise if one elects to attend a local aerobatic course of instruction, as one will normally use the school machine. However, it is possible to make arrangements to bring along one’s own machine to the school, or to hire machine and instructor separately. The most important aspect of this is to make sure that the instructor is really capable. A good instructor can teach well on a mediocre aeroplane; a mediocre instructor will never achieve results, even on the best aeroplane in the world. Bear in mind also, that just because someone is an instructor it doesn’t mean that he is any good at aerobatics.

There is a wide variety of equipment to choose from, and the basic manoeuvres can be reasonably demonstrated in all of them, but here I have selected the Stampe SV4B as an example of a good basic and intermediate trainer, which can be, and is, currently used in all British competitions.

The use of such an aeroplane necessitates the purchase of various items of flying clothing; in any case if one is intending to fly aerobatics, these items will always be useful in other machines in the future.

Aerobatic aeroplanes tend to distribute oil with great impartiality, so in order to protect one’s clothing a good flying suit is necessary. This should be light and comfortable, as even an open cockpit can get hot when the workload goes up. Zip or velchro pockets are essential for retaining loose cash, keys, etc. Never, never, fly aerobatics with loose articles in your pockets, which can find their way into control runs. If there is no alternative, tie them securely into a handkerchief.

The next item is a good helmet, close fitting, and with ventilation holes if possible. This may be augmented by a bone-dome, which although a little cumbersome could make all the difference in an accident.

I know of a pilot who received slight injuries when another aircraft taxied into his machine. His bone-dome saved his life. Make sure that the retaining straps of headgear are securely fitted, and ensure that the bone-dome is the correct size.

An oxygen mask with microphone is generally better for communication as a throat mike doesn’t operate well in an open cockpit. A good pair of gloves is essential, not only for protection, but also to ensure that one’s hand does not slip from the control column, and finally a good set of goggles should be bought. These should afford a good field of vision, and should be tight enough to resist the effects of slipstream. I personally use Mk 8 RAF goggles, with parachute elastic. Even in a closed cockpit, goggles should be carried, as a precaution.

The most expensive item of equipment for the aerobatic pilot is a parachute; and here one must decide on one’s priorities. If one is flying, as one should, above 3,000 feet, during the course of instruction, it is sensible to carry a parachute, in the same way that one takes out insurance before travelling on an airline; not with any intent, but just in case.

With the pilot now suitably equipped, let us look at the aeroplane. A good pre-flight inspection is essential before each flight, as the aerobatic aeroplane is worked hard. One gets to know the areas which require specific attention on each type. At the end of a day’s flying the aeroplane should be thoroughly cleaned, not only because if oil is left on the surfaces, they will deteriorate, but also because it is the one way of ensuring that every square inch of the aeroplane is examined. The accelerometer is not reset by the last pilot, but is left for the next pilot to see, so that he knows how hard the machine has been flown. Oil and fuel are especially important, as an aerobatic aircraft can get through these commodities remarkably quickly. On some types, dual instruction cannot be given if the fuel tank is full, while on others the inverted system will not run unless the tank is full.

The safety harness should be examined carefully for fraying and oil contamination. The Stampe in particular tends to have its cockpit floor liberally coated with oil, and this should be wiped up. A soft cushion should never be used for aerobatics, as it will compress under g and cause the harness to slacken off. It will also put a strain on the spine during high g manoeuvres, and will create a feeling of insecurity generally. A rock hard cushion is not so comfortable in the cruise, but it will improve your feel for the machine in aerobatics: a parachute gets rid of the problem, as it is designed to fit into the seat pan.

There are different combinations of connecting the straps, but experience has indicated that the best method is to start with the seat fully down. The secondary harness (connected to the airframe) and the adjustable negative g strap are then connected, and the combination is pulled as tight as possible. This is where most people run into trouble; they tend not to tighten the harness sufficiently: it should be so tight that it almost hurts. It will ease off in flight to a comfortable and secure level. Next the primary harness is tightened in the same way, so that one is left absolutely immobile and not a little breathless. Finally, the seat is raised one or two notches, which has the effect of tightening the lower straps even more. I cannot place too much emphasis on the need to be securely and tightly strapped in. Even so, all the straps will loosen off in flight but will still result in the pilot being very firmly restrained in the pelvic area, which is close to the pilots own centre of gravity. The pressure of the straps across the chest will have eased off, and this is very important for inverted flight, where nearly all the weight is on the negative g strap, and the shoulder straps serve merely to stabilise the upper body. If these shoulder straps were too tight they would tend to restrict breathing during inverted flight and would cause the pilot to tend to hold his breath. This would result in an increase of blood pressure to the head, and could result in an increase in the value of negative g being experienced, so that although the accelerometer might show -2g during an inverted turn, the pilots upper body and head might well be subjected to -4g, with the attendant distress. The real secret of combating negative g, as we will find out later, is to relax.

With the pilot firmly strapped in he must ensure that he is as comfortable as possible, as any distraction will reduce his learning potential; and he must be able to reach all controls and to move them easily throughout their range. This sounds very basic, but it is surprising how many pilots either can’t see (sitting too low) or perch themselves so high that they couldn’t possibly reach full rudder.

At last, firmly installed, the pilots reaction is that he is an integral part of the aeroplane; but now he must consider this in a different sense, that is, that the aeroplane is now an extension of himself. It is now not going to be a question of moving the controls and the aeroplane does his bidding; he and his aircraft must operate as one integral combination.’

4

Pre-aerobatic training

Strangely enough, the initial exercise can be carried out on any type of aeroplane, even commercial types, for this is revision of the first thing all of us learned in the air; straight and level flight. “What has this got to do with aerobatics”? One might ask; and the answer is that it forms the basis of all competitive manoeuvres. Given a fairly constant weight it follows that for straight and level flight at varying airspeeds, there will be a noticeable change in aircraft attitude, and since the speed will vary from stalling speed up to VNE, the aircraft will therefore be subject to the maximum attitude change. For example, flying off level from the top of a vertical roll is going to produce a very different attitude from the high speed horizontal line which preceded the manoeuvre. It will be seen, therefore, that one must obtain the instinctive knowledge that the selected attitude at any given speed will result in level flight. The demonstration of two speeds for a given power setting, reducing to the attainment of the minimum drag speed, forgotten by most private pilots, now assumes new significance. Obviously, when the minimum drag speed has been found, it follows that if the aircraft can be held for reasonably long periods near this speed, at full power, during a sequence, the engine will be able to impart the maximum energy to the aircraft, in terms of kinetic or potential energy, and the importance of this will be seen later.

Maximum and minimum attitudes for straight and level flight