MANEUVERING AIRCRAFT IN FORMATION
By the late Lieutenant Edward L. Ericsson, U. S. Navy
This article was originally delivered as a lecture to new pilots joining the Torpedo Plane Squadron at the Naval Air Station, Hampton Roads, Virginia, in May, 1922. Lieutenant Ericsson attended the football game at Annapolis on October 21, having flown up from Hampton Roads with a flotilla of planes. He was killed, on October 26, when a plane in which he and another officer were making a test flight dropped almost vertically from a height of 800 feet. The manuscript was received at the Naval Institute on the day of his death.
The article is thus of interest not only from the importance to aviation of the maneuvering of planes' in formation, but from the fact that within a few days after the manuscript was sent in, Lieut. Ericsson gave his life to the development of aviation.
Editor.
At the present time there is very little information regarding the maneuvering of large numbers of naval aircraft. In the past, the flying done by the navy was largely limited to instruction and patrol work for seaplanes, and fleet spotting for land planes. This called for single plane flying, and so comparatively little formation work had been done.
Lately, however, naval aviation has broadened in scope. It is planned to have bombing, torpedo, spotting, scouting, and combat squadrons which will use both land and seaplanes. Gas attack, smoke screens, and photography will be used as auxiliaries. The possibilities are infinite, and call for large numbers of aircraft maneuvering and working together.
To do this expeditiously and efficiently, obviously requires methods of maneuvering, tactics, and communication, which are as simple as possible. Groups of aircraft will function in a similar manner to the various units of the battle fleet or an army. In action each will depend upon the other, and similar policies and tactics will govern them all as far as the size, type, and design of these planes will permit.
Some thought must be given to this by everyone, and the information thus gained by thought and experience promulgated throughout the service. Such methods as have proved themselves efficient will become axiomatic, and the whole system can thus be built up step by step on sound tried lines. A beginning must be made somewhere, and it is with this end in view that the present elementary article on formation flying is written.
A great many formations have been flown by the Torpedo Plane Squadron, The methods which have seemed to be the best will here be outlined. Little claim is made to originality, for the experience and opinions of others are being used, and these, coupled with the results of a great many experiments and much practice, have determined the doctrine of the Squadron. No claim is made that these methods are the only ones by which similar results may be achieved. However, they have been carefully thought out and have worked successfully.
Primarily, an explanation will be given stating the reasons for, and the great importance of, formation flying, and why proficiency in this kind of flying is so essential an accomplishment to a pilot flying any type of airplane.
The effort of a number of planes can usually be coordinated best if they are maneuvered together. This is true of any kind of attack, bombing, or torpedo work. Similarly, in being attacked by an enemy, it is the best method of defense. Each plane, if a multi-place one, can defend the plane ahead, the plane behind, and itself by machine gun fire if it is in formation. However, if any plane strays from its formation it will become the easy prey for an enemy lurking behind a cloud or flying at a higher altitude.
Then too, the formation leader must have the planes near enough to him so that he can see them. It is even more necessary that they be able to see him and receive his signals and follow his movements in maneuvering, attacking, and retreating.
In bombing, particularly, it is necessary to fly certain types of formations, not only for the above mentioned reasons, but so that the desired pattern of bombs can be dropped when bombing a moving target, such as a ship or train. This is absolutely necessary to insure hits.
Another good reason for formation flying is one which has directly no military value. The pilot learns the "feel of plane" to a greater degree in formation flying than any other way. He learns absolute control of his machine. He becomes part of it and ceases to fly mechanically and by rule. There can be no skidding or slipping in formation flying.
After having explained why it is necessary to fly formation, the next question of how to fly it will be taken up. There are several factors which are necessary to do so properly.
The primary, and most important requisite, is a good leader. He must know how to direct the other members of his flight and to keep them together. He must be able to fly properly himself and know how to take advantage of the clouds and the sun. He must keep a weather eye out for enemy formations or decoys, so that he will not be surprised. His must be the eyes of the formation, and his is the responsibility for the safety, proper directing, maneuvering, and handling of the flight.
The second requisite is the absolute maintaining of the formation. Planes must be kept in position, both in a vertical and a horizontal plane. They must not stray and in case of one having to drop out, the next behind must immediately close up the gap. This is necessary for several reasons.
In case the formation is attacked, each plane defends not only itself, but the plane ahead and the plane behind. The blind angles of each plane are protected and covered as far as possible by the type of formation used. The greater the blind angles of the plane in front, the more obtuse will be the angle of the "V" of the formation.
Another reason for staying in position is that the leader can make his signals seen and understood. Visual signals from a plane are hard to understand anyway at best, and if the planes are not closed up the difficulty is augmented.
The third essential is a simple system of signals whereby the offensive and defensive qualities and possibilities of the formation can be most advantageously utilized. As has been stated before, signals of any kind are rather hard to receive, and for this reason, the Squadron Doctrine should determine largely the particular line of action in each individual case.
There are two methods of signaling and communicating in the air. The most positive, and the one most used up to this time, is visual signaling. Radio and radio telephones have not been developed to the point of reliability as yet, but they will undoubtedly be perfected in the near future, so that their use will be practicable and essential.
Visual signals can be made with the arms, by zooming the plane, by tipping the wings, by little hand flags, or by Very Pistol. For closing up and opening out, or raising and lowering the planes directly behind him, the leader can use his arms. The planes receiving this signal can pass it along to the rear. In forming, breaking up, landing, attacking, retreating, and for other more complicated maneuvers, the more unmistakable signals of zooming and tipping the wings are the best. In bombing, flags or a Very Pistol have been used quite successfully. However, the most positive way for the planes behind the leader to release their bombs at the proper time is to watch the fall of the bombs in the leading plane. For simple 90° or 180° turns no signals at all are necessary because it is very easy to see the leader go into a turn and follow accordingly. Very often, however, the leader will raise his right or left arm for a turn and raise it again when he straightens out.
In large planes, where it is possible to carry a radio operator who can spend all his time operating the set, marked success has been attained in all kinds of communication. It is necessary, however, to have a good set and an operator who is experienced.
The fourth factor in formation flying is a knowledge by all hands of the chain of responsibility. In case the leader finds it necessary to leave, the command should pass along to the next man, and all of the members of the unit should be so indoctrinated that each can take up the leadership competently, and carry out the mission properly, along the lines which were planned, and that there is no question in the minds of any, who the leader is. This calls for a complete understanding and co-operation of each individual pilot. The minds of all should function along similar channels, and the mission and the procedure in carrying it out be so well understood by all that a change of leadership will affect but little the morale of the flight or the resultant effort which is the mission.
The type of formation flown is usually "V" or some sort of diamond. The largest number of planes that can be maneuvered by a single leader in one unit is seven or eight. Even that number is somewhat unwieldy to handle quickly. A five or six-plane formation is about the handiest of all. The "V" is used for an odd number of planes, whereas with an even number, one plane will fly directly behind and below and thus make a modified diamond.
In bombing a stationary or moving target, it is usually desirable to drop the bombs in some sort of a pattern. The factors which determine the shape of the pattern are as follows: (a) the type and shape of the formation, (b) the number of bombs carried, and (c) the time interval of dropping. The arc of visibility of the plane affects the shape of the formation because in some planes it is difficult for the pilot to see a plane ahead if it is at a lower level. In this case the following planes step down from the leader instead of up, as is usually the case.
Planes fly above the leader for two reasons. First, the leader can see all of his formation better if they are above him. When planes are below he has to look down on either side of the fuselage, and this is difficult in any type of plane and impossible in some. The second, and even more important reason, is that a plane can protect the tail of a plane ahead if it is flying above, whereas it becomes almost impossible if the rear plane is flying below. This applies only to single motored planes with fixed guns.
Where the numbers of planes to be maneuvered is more than eight it becomes necessary to form several flights, and to fly as a group. A group is rather similar to a single unit, that is, in echelon or "V" shapes. However, each flight is at a different altitude from any other. The best difference in altitude is about five hundred feet. The diagrams show these two methods. The angle of the "V" should be kept as acute as is possible without having the wing flights overlapping the leading flight. In other words they shouldn't forge ahead.
In extended operations, the gasoline capacity has to be taken into consideration. Time and operations schedules must be followed according to the military plan. For this reason the actual forming and beginning of an operation must be prompt and expeditious. The quickest and best way to form a flight is to take off from the water or the ground in formation. However, it often becomes necessary, because of a restricted field or area of water, to have rendezvous over some designated spot. The best way to do this seems to be as follows: all planes, but the leader, will follow each other in a counter clockwise circle. Their order in the circle will correspond to their number in the formation. No. 2, who is second in command, will lead the circle. The leader stays outside of the circle at 100 feet lower altitude. He meets No. 2, who does a wingover or tight flipper turn and fall's into place. The leader continues outside in a clockwise circle and picks up all of the other planes in a similar fashion. The diagram will explain this more fully.
A group is formed by the leading flight picking up the other flights one by one in a somewhat similar fashion. Flights rendezvous over some specified area with 500 feet difference in altitude between flights. The leading flight will maneuver previously, so that it comes in toward the others at a converging course.
When the squadron has been formed, unless the radio communication, is quite perfect, the flights following will each govern their movements by the leading flight. The mission of the group will determine, to a large extent, its action in the event of an attack or in being attacked. Generally speaking, however, all flights will follow the leader.
Maneuvers should be made as simple as possible, and should consist only of such movements as will expedite and make easy the handling of a flight group. Complicated movements only tend to cause confusion.
The first thing a beginner at formation flying learns is the making of ordinary turns. The inside turn particularly, while actually being the easiest to do properly, seems to be the most difficult, until the knack has been mastered. The leader goes into a turn making average cruising speed. He may or may not give a signal first, it matters little which. He must under no circumstances skid or slip, if he does so he will get out of position relative to the whole formation. The planes on the outside crowd in very slightly and increase speed so as to make up for the additional distance which they have to go and still stay in formation. The inside planes decrease speed materially and drop down below the level of the leading planes and "step down" in a similar manner to their "stepping up" on straight away flight. Thus the whole formation is banked and every plane is flying at a different level. This obviously prevents any collisions, or being in each other's way, or obstructing each other's view. When the leader straightens up, the inside planes pull up to position as before. The great tendency of pilots flying inside is to drop too low and to forge ahead. Sometimes it becomes necessary to almost stall the plane to stay in position. If any plane drops too low it forces the plane behind down also, and makes it difficult for all to get back up when flying straight once more.
Crossover 90° turns are quicker than ordinary turns, but are, however, somewhat dangerous. The leader makes an ordinary turn as before. The outside planes dive under and come up into position. The inside planes simply cross over the outside planes, and fall into position. The diagram explains it more clearly than words can.
For a quick 180° turn, which would be used in a sudden retreat or in an attack from the rear, a renversement is the quickest. This can be done only with planes that can stunt. The leader does renversement to the right or left. The planes on the right flank each make one to the right in succession as soon as the plane ahead has completed its turn. The planes on the left flank do a renversement to the left in a similar fashion. After it has been practiced for a while each pilot will be able to judge when to start, relative to the plane ahead.
At times a Lufberry, or Milling circle has been used by single-seater planes as a defensive measure against attack by superior numbers. The principle of this is, that if all planes are flying in a close circle at the same level, each plane will be able to protect the tail of the plane ahead of it. It is not as practical as it seems because it is rather difficult to keep a close, enough circle. Then too, it cannot be moved quickly and the circle must be kept up until the attack has ceased or help has arrived. A straight away formation is much better for multi-placed machines. The Lufberry circle, however, is a very pretty maneuver and is done as follows: Upon a designated signal the last plane on the right flank does a wing over or right flipper turn to the right and continues in a circle, keeping the same altitude. The other planes on the right flank and the leader do the same thing. The planes on the left flank follow in behind the leader. The circle is tightened up by the first plane to turn, and the size is determined by the number of planes in the formation—the more planes the larger the circle. The flight is reformed by a signal from the leader. He can dive down through the circle and have the other planes fall in as best they can. The neatest way, however, is to have the leader give a zooming signal, and at the end of it he and all planes which were on the right flank in the beginning will do a wingover or flipper turn to the left. The planes on the left flank will merely ease in behind the leader. The leader should make less of a turn than the planes further back and if he throttles down, they will have little difficulty in catching up and getting into position.
All of these methods of maneuvering have become part of the Squadron Doctrine, and a word of explanation will be given to define the term. Doctrine means method, and indoctrination means knowledge of method. The personnel of the squadron must be indoctrinated into the squadron methods as soon as these have been evolved. This applies to every endeavor and every bit of work done by the squadron. As far as possible methods should be standardized with this end in view. Operation orders, flight formations, rendezvous, flying signals, beach procedure, division routine, officer-of-the-day duties, and a hundred other things should all be done in certain standard ways, which have been thoughtfully worked out, and proved by experience. Then after they have been learned, the issuing of orders will be very much simplified. The less supervision and explanation of details which is necessary, the more complete the indoctrination of the squadron. When the subordinate officers of an organization are properly indoctrinated it is only necessary for the commander to explain briefly the mission to be performed and the general method of doing it. His subordinates then merely follow the tried and accepted methods with which they are all familiar. The minds of all function along certain known and tried lines, and each man knows what he and the others are going to do, and how it is to be done. In the absence of the commander the mission can be carried out as well as if he were present, because his subordinates all know what he would have done were he there to direct himself.
Doctrine is so very necessary in formation flying. There must be a mutual confidence and understanding between the leader of a flight or group and his subordinates. Acts on the part of each, which are different from the preconceived plan, must be construed intuitively as being the right thing to do under the circumstances. When orders are not being carried out the leader should know that it is utterly impossible for the subordinate to do so. When the leader does something different from the plan, as conceived on the ground, the remainder of the flight must know that his reasons are sound, and that his actions are the best under the circumstances. The members of a flight must understand each other, whether things go right or wrong. When this becomes so, they have become properly indoctrinated.