The Values of Various Aeroplane Groupings in Times of Peace and War
NINE HAWKER HARTS flying in V formation. Each pilot, except the leader, keeps station by watching closely the machine in front. So closely does the pilot have to watch the next machine that he flies by comparison with it and by nothing else; he may not even notice the ground. Thus the movements of the formation depend entirely on the leader.
WAR flying, although its effect as a stimulus to design development has been questioned by those best able to judge, was certainly responsible for the introduction of formation flying on a large scale. From a military point of view formation flying is of supreme importance and also of considerable complexity.
All formations in the air are built up on the foundations provided by a leader and a sub-leader or sub-leaders, whose aeroplanes are appropriately marked, so that they can readily be distinguished by all other members of the group. Even formations of exceptional size, such as that seen at the last Royal Air Force Display at Hendon, London, in 1937, conformed to this method of building. The bigger the formation the greater must be the number of subdivisions and sub-leaders. There are wide differences between
close formation flying and open formation flying. Open formation flying came first, but it merged almost imperceptibly into close formation flying and that has been developed to its present stage during peace time. All war-time flying was in open formation.
In a formation the only independent member is the leader. Theoretically he is able to fly exactly as he wishes; in practice he cannot do so and must confine his manoeuvres within strict limits. Theoretically, however, the leader is free and all the other machines are, as it were, pinned to him through one another.
Let it be assumed that a squadron of nine machines is flying in close formation in V. The leader is at the point of the V; the pilots spreading out and back to the right are “dressing” - to use a military term - on the machines next to them on their left, and the pilots spreading out and back to the left are dressing on the machines next to them on their right.
STEP FORMATION OF THREE MACHINES as seen from the side. The machines are behind one another, but B is higher than the leader A, and C is higher than B. Should the leader be flying at full speed, the other two machines can make use of their greater height to catch up if this proves necessary, during combat or during the preliminary manoeuvring.
Thus each pilot is watching one machine, and the pilot in that machine is in turn watching the next one to him, and so on until we reach the leader who - again theoretically - need not watch anybody. The formation is therefore linked up, each machine to the next and all of them to the leader. In close formation work the pilots are keeping such close watch on the machine next to them that they do not notice the ground, They fly by comparison with the next aeroplane and nothing else. If the leader of the formation chose to dive his aeroplane straight into the ground, all the other machines in the formation would be expected - in theory - to dive into the ground in their proper positions behind him.
Although the pilots of a formation do keep a rough eye on what is happening, they are in reality as well as theoretically much occupied in keeping station with the machine on which they are dressing. This is especially so in close-formation aerobatics of the kind seen at aviation displays. It is possible for the formation leader to move the formation about with the other pilots being only vaguely aware of where they are going and which way up they are. For in a formation loop, only the leader judges his speed and attitude, and the others are automatically brought over the loop with him. If he makes a bad loop, they also will make bad loops.
So it is true in theory and in fact that the members of a close formation are concerned only with the machine next to them, according to the direction in which they are dressing.
Open formation flying is, in some ways, more complicated than close formation flying.
The original object of open formation flying was to keep a patrol together when on the war front and to enable that patrol to strike together. The V formation was the first chosen, because it has the advantage that it defines the leader and enables him to remain out in front where he can plan his manoeuvres independently according to the tactics demanded at the moment.
Three aeroplanes in V are the first unit and they remain today the basic tactical unit of nearly all air forces. The leader is in front and, in open formation, the other two machines are on either side of him, slightly behind him and on a higher level. The object of the greater height of the two machines following is to give them what amounts in effect to a reserve of speed, even when the leader is flying at full throttle. The two machines can use their extra height to put the noses of their aeroplanes down and, if need be, close up on the leader.
This stepping-up of the formation from front to rear is almost invariable in war, but it has frequently been changed in peace. Some of the large formations, to keep the machines at the rear clear of the slipstream of those in front, have been stepped down. There is, however, little likelihood of the stepped-down formation being used in war, and so it must be regarded more as a parade device.
(Above left) PATROL OF SIX SINGLE-SEATERS. The machines to the right and left of the leader, A (see adjoining diagram also) are displaced sideways to the left or right and are higher. The sub-leader F is in the highest position of all.
(Above right) PLAN OF THE FORMATION shown in the diagram to the left. The sub-leader is in a position directly behind the leader, but on a higher level. The front view of this formation would be in the shape of a diamond.
A flight of six machines in time of war would adopt the following formation. Again the leader would be out in front. Behind, above and to right and left of him would be four other machines, two on either side, and finally, in line behind the leader and highest of all, would come the sub-leader. The formation is no longer truly Y-shaped.
All the machines behind the leader have a reserve of speed, stored in the form of extra height. They can therefore close up with him quickly at any time, a factor of special importance on active service. It would be difficult to say just how far apart are the machines in open formation, for an open formation is essentially elastic and there is none of the rigidity about it that is found in close formation.
The reasons for the selection of open formation in time of war are that the risks of serious damage by anti-aircraft fire are slightly reduced when the aeroplanes are spread about and also that the watch on the sky for enemy machines, which every pilot in a war formation is expected to keep, cannot be adequately maintained if any attempt is made to fly in close formation. With open formation each machine is given the greatest possible freedom of individual action.
In some ways open formation is easier than close formation, but in other ways, as already mentioned, it is much less easy. For example, when the leader decides to make a 180 degrees turn quickly, even if there are only a dozen or eighteen machines in the formation, those out on the wings will be a considerable distance from the leader and will follow a far different course in turning from the one that he follows.
If the leader turns to the left, the machines on his right will have an enormously greater distance to travel than the ones on his left. It is true that they all have extra height to play with and can therefore speed up considerably. But supposing the leader is travelling fast, perhaps just before engaging the enemy, when he wishes to make the turn, the wing machines will still be unable to keep position even by using up their excess height. Moreover, at the end of the turn they will be as low as or lower than the leader and the essential basis of the formation will have been destroyed.
Similarly, the machines on the extreme inside of the turn will have some difficulty in flying slowly enough to keep their correct positions in the formation. In close formation the problem is not so acute because the wing machines are far less widely spread and therefore the radius of the turn they must make differs less widely from that made by the leader. But in open formation it would be utterly impossible to make a rapid turn with a formation even as small as six machines without throwing the pattern entirely out, unless special measures were adopted.
These measures consist in “crossing over”. The rear machines swing across one another, above and below, according to a prearranged formula. Thus the difference in the radius of the turn taken by the inner and outer units is cancelled out and the formation completes its turn correctly arranged with all the wing machines still retaining their margin of height over the leader.
This crossing over is an extremely difficult proceeding. It was, however, developed by some of the war-time squadrons to such an extent that quite rapid turns could be made and the machines would be in position as soon as the turns had been completed.
With simple open formation there is less juggling with the throttle than is needed in close formation work. In close formation work the pilot keeps station by keeping his hand on the engine throttle and by seeking to anticipate any change in the relationship of his machine with the one on which he is dressing. In open formation work there is more latitude and, although the throttle is still used for keeping station, it is not used so intensively.
Compound formations - so far as active service work is concerned - consist in layer formations. Squadrons or wings are ranged in formations in V in the manner already described and are then placed one above the other at intervals as great as the visibility will allow with full observation. Layer formation was common during the war of 1914-18 in aerial fighting in which aeroplanes were used as “bait” for enemy machines. The lowest machines formed the bait and the others waited in their respective layers at a good height above them. The bait machines sought to attract as many enemy machines as possible and then the others came down in a dive from above.
Close formation work is mainly a parade manoeuvre. Machines form up in V, in flights, in squadron, in line ahead and line abreast, in diamond, in line of flights ahead and so on. The different shapes are as many as it is possible to devise and the machines can change from one formation to another with great rapidity because the leader, in close formation work, invariably keeps the speed of his machine well within the limits of capability of the type and so gives all the other machines a big margin of speed with which to play when they are changing position.
Close formations can be flown as one; this has been demonstrated at many aerial pageants. A turn can be made with all the aeroplanes banked over as if they were threaded on a bar. Again, aerobatics are possible with the machines tied together with lengths of shock-absorber rope. Close formation work is attractive to watch and it is excellent training in flying discipline and in the details of control. In war time it would be used, not for fighting purposes, but for moving squadrons about the country. Groups of machines can be taken off from the aerodrome in formation, and much time is saved, compared with the method of taking off independently and then meeting at a prearranged point.
FRONT VIEW OF TWELVE MACHINES DISPOSED IN GROUPS OF THREE. The leader is A, and B and C are behind and above him. The two groups D E F and G H I are similarly arranged and are disposed as groups above and behind the leading group ABC. The highest group J K L flies centrally above the others.