Britain’s Air Effort

FIGHTING efficiency in war is partly determined by the speed with which experience in the field can be interpreted and utilized. Practical achievements in the employment of the results of experience during the year 1942 fall into three main groups -- strategical, tactical and technical. Obviously, technical progress is interwoven with, and has a direct influence on, strategy and tactics. This is nowhere more true than in aviation. Indeed, an outstanding example of the fact was provided during the opening phase of the North African campaign when bombers based in England were employed to attack supply ports in northern Italy that were feeding Field Marshal Rommel's forces and that were being got ready to feed Axis forces in Tunisia. But although this close linkage plainly exists between technology and strategy and tactics, we here shall consider each separately and only occasionally shall note striking instances of collaboration.

I. AIR STRATEGY

Right from the beginning of the war, the proper employment of heavy bomber forces has headed the list of strategical problems. The Royal Air Force always regarded the heavy bomber as an important weapon, and has steadily built up its heavy bomber strength. In this it has been proved to be right. But experience has caused it to modify its views as to its use.

Marshal of the Royal Air Force Lord Trenchard always was a powerful champion of independent air action. Indeed, he was advocating such action before the brilliant Italian writer General Douhet, although Douhet's name is more widely known than his in this connection. In its extreme form, the theory of an independent air force rests upon the power of strategic bombing. If it be true that a nation can be knocked out by bombing alone, it follows that an air force ought to be independent. But the hard school of war has taught that there is a fallacy, or rather an incompleteness, in this argument. Experience has emphasized that air power is as much dependent on supplies as all other forms of power, and that the idea of an independent air force is and will be an illusion until such time as all supplies for that force can be carried by air. That stage certainly was not reached in 1942. There are no signs that it will be reached during the present war (outside such special cases as the Burma Road), though everywhere we see that we are moving towards it.

In the meanwhile, air strategy must conform to the facts of the day -- and these are that the supplies for an air force must to a great extent be moved by land and sea. Bombers and fighters working in the Libyan desert were largely dependent for their supplies upon sea and land transport. Similarly, the air forces working along the French North African coast drew heavily on sea transport for their supplies. It is difficult to see how fuel and bombs could be carried by air in sufficient quantity to furnish the entire support for air forces working in such conditions and at such distances from their main bases, at any rate for some time to come. So long as the fundamental fact remains that an air force draws its strength from the land and the sea it can never be independent. It can be, of course, autonomous, as it is in the British three-Service arrangement; but even autonomy has had to be modified in the light of experience, and the Royal Navy has not only had to assume full operational responsibility for the activities of the Coastal Command of the Royal Air Force but it has also had to be given leave to build up its Fleet Air Arm on a much larger scale than had originally been visualized. Similarly, the British Army now disposes of glider forces and parachute troops and has many pilots in its personnel. The Army Coöperation Command of the Royal Air Force contains numbers of Army officers assigned to it for duty.

Thus we arrive at the conclusion that air force independence varies with the extent of air-borne supplies. Most of us who believe in aviation think that at some remote future date air forces will become truly independent. They will not only work in the air but they will move all their equipment and supplies by air. But as the war has proceeded, British thinking has been evolving; and by the end of 1942 it no longer was as confident as it had been two years earlier that the war could be won by strategical bombing alone. Indeed, the view was officially repudiated by eminent Royal Air Force officers. Strategical bombing was still regarded as an important factor for striking at the enemy -- perhaps the most important -- but it was seen to be related to the other factors of land and sea action. The whole thing can be put in another way: that the military axiom of concentration of forces on the critical point at the critical time demanded that the program and pattern of strategical bombing should conform to concurrent land and sea operations. The catchword had changed from strategical bombing to the "balanced force" of all the arms.

In the western desert, Air Chief Marshal Sir Arthur Tedder and Air Vice-Marshal Sir Arthur Coningham developed the coöperative side of air force work to a high pitch of efficiency. They devoted themselves to perfecting the technique whereby an air force can work with an army; and in General Alexander's break-through at El Alamein and in the subsequent pursuit to Tripolitania this technique proved successful. At the other extreme, the strategical bombing of Germany was continuing, in the early part of last year, without much apparent direct relation to other activities. It is natural that the United Nations should approve of this bombing of Germany. Germany's method was to wage war in other people's countries while keeping the Fatherland itself free from war's dangers and inconveniences. The Bomber Command of the Royal Air Force determined from the start to get at Germany, however difficult the task and however costly its execution. It has been difficult and it has been costly. German defenses are extremely strong and extremely efficient. Antiaircraft fire is intense near all the main targets. Searchlights are used in hundreds. The night fighter technique has been improved, and it is aided by numerous scientific devices which enable a fairly high percentage of night interceptions to be made. The Bomber Command thus faced fairly heavy losses when it struck into Germany. But none of these losses ever altered its determination to multiply its direct attacks on the chief instigator of the war.

The emotional satisfaction produced by heavy raids upon places in Germany undoubtedly tended for a time to upset a clear appreciation of the real position. With every raid there rose a chorus of approval in the United Nations, and the prophets of absolute air power stated more and more strongly their views that available industrial resources should be devoted mainly to building up the strategical bomber offensive. In those circumstances, it was difficult indeed to gain attention for the view that air, land and sea forces working in close collaboration were stronger than the sum of their individual strengths. But in 1942, the year with which I am dealing, that view did gradually gain favor. It was recognized that the promises of the Secretary of State for Air, Sir Archibald Sinclair, and later of the Commander-in-Chief of the Bomber Command, Sir Arthur Harris, were made in good faith. It was seen that the captains and crews of the bomber aircraft were ready to take all risks to get at Germany with the biggest weights their aircraft could carry. But it was also seen that Germany is a large place, that it is being supplied with war materials from the conquered countries, and that in consequence the most prodigious efforts by the bombing forces might not be sufficient to deliver a knockout blow.

Simultaneously the calls for air support for the Royal Navy and for the Army became louder and more persistent. The aircraft was proving itself a superlatively good weapon for countering the U-boat, and this led to an increased demand for long-range machines capable of carrying heavy bombs, mines, depth charges and large caliber guns or cannon. The factories, in Lord Beaverbrook's phrase, "rolled out the bombers." But the demands were insatiable, and the strategical bomber forces did not grow quickly enough to bring within sight the time when Germany could be knocked out by bombing alone. The realization gradually ensued that the bomber force must strike at Germany as often as it could, but that it must also be ready to collaborate directly with other forces. In the western desert, large four-engined machines began to take part in operations. The Handley Page Halifax was mentioned in the official communiqués and the American Consolidated Liberator and Boeing Fortress bombers. Before this, the bombing in the western desert had mainly been the responsibility of medium and light machines. The introduction of heavy bombers, therefore, was the outcome of an extension of the lines of communication, or, in other words, an increase in the responsibilities of land and sea transport.

When we take into account the gradual increase in the attacking weight in the western desert, the air support provided for the American and British troops in French North Africa, and the increasing air protection for Atlantic convoys, we may conclude that this important phase of World War II showed the need for using the air coöperatively rather than independently. Independent bombing was essayed to the fullest extent possible. It brought small results in relation to the gigantic events of global war. But air power used in coöperation with land and sea power had begun to produce results which offered genuine strategic gains. Long-range strategical bombing was not in the least discredited. On the contrary, its value was shown to be great. What had been demonstrated was that its value could be multiplied several times over if it were mingled with the values of land and sea work. Strategical bombing might be partially wasted if it were directed against an objective which could not be subsequently assailed by land or sea forces. It would be used to the full if the objective, after being fully trounced by long-range bombers, could subsequently be threatened by swiftly advancing forces on the land or the sea.

One additional strategical aspect of the air war must be considered. I would emphasize, however, that I am taking account here of those aspects which present themselves most clearly to us in the United Kingdom, and am largely ignoring the equally important aspects which arise in the war in the Pacific. This one-sided view will be excused, I hope, by the fact that I am familiar at first hand only with the air war as it is being waged in the West and that any comments I might make on the air war as it is being waged in the Pacific would be second-hand. The additional matter to which I would like to direct attention concerns the general strategical pattern as it emerged at the end of 1942. General de Gaulle said in the latter part of November that the land of France had become the strategical center of the western war. Accepting that statement as being true -- and there is nobody with a keener strategical sense than this Frenchman -- we may say that the problem of the United Nations consists in bringing to bear upon certain points in the large circumference that has France as its center an air force which is capable of breaking through, or at any rate of preparing the way for a break-through.

On the Russian front there are obvious difficulties in providing the air force necessary. Let us assume that Germany's first-line air strength is between 4,000 and 6,000 aircraft. Then in order to achieve air supremacy (which is more than air superiority) on the eastern front, Russia would require a first-line strength of at least 6,000 aircraft. Since many of her big factories have been overrun by the Germans we could hardly expect her to develop such a striking force for some time to come. In the coastal region in the West, Great Britain can obviously develop a striking force sufficient to create a break-through; but there is the additional problem there of that gigantic tank trap, the English Channel. Air forces sufficient to blast a way might be available, but the subsequent step of landing adequate armored units might be fraught with extreme difficulty and danger, as was indicated in the Dieppe raid of August 1942. On that occasion, the Allied air forces maintained ascendancy in hard-fought battles which entailed losses on each side of something like 100 aircraft.

In North Africa the position was much better than in either of the regions so far mentioned. Here the Axis Powers had greater difficulty in assembling aircraft in very large numbers and there was an opportunity for an Allied break-through. In the last quarter of the year we seized this opportunity with both hands, proving conclusively the farsightedness of the planning inspired by Mr. Winston Churchill and President Roosevelt. The expedition raised additional problems of supply and created a new pressure on shipping. On the other hand, in this North African region the United Nations were able to bring to bear air forces of sufficient power to achieve local superiority over the Axis wherever the fighting mounted to a climax.

We see, then, that there are two concentric circles which have their centers on France -- the defensive air circle of the Axis and, just outside it, the offensive air circle of the United Nations. The very fact that the United Nations were exercising their air power centripetally implies that their problems of supply were greater than those of the Axis. But their output was also greater, so that in consequence they were able in some measure to overcome their positional handicaps by mass. In a smaller measure, as has been explained, they were able to overcome these difficulties by the ingenious use of the long-range capabilities of some of their machines, among which must be quoted with approval the Avro Lancaster bomber with its four Rolls-Royce Merlin engines.

At the end of 1942 the strategical situation of Great Britain remained on the whole unfavorable. For, to paraphrase a famous remark of Napoleon's, it may be said that the strategy of a state lies in its geography, and the small islands of the United Kingdom were obviously nearer to the advanced bases of the German air forces than the bases in those islands were to the essential targets in Germany itself. I have quoted before now the statement of a Royal Air Force officer, Air Marshal Peck, which seems to me to present in perfect form the fundamentals of the case as between Britain and Germany. He likened the strategical situation to the picture in a comic paper which showed an extremely tall, thin man dancing with an extremely short, fat woman. Two friends watching the dancing from the edge of the floor are speaking to one another, and one says: "You know, Smith, when one is dancing with Mrs. Tunningley-Howitzer she always seems to be nearer to you than you are to her." Germany's air force has been strategically nearer to Britain than Britain's air force has been to Germany. That is one of the results of the early German conquests, felt especially ever since the France of Marshal Pétain signed an armistice with the Germans. In the past year, however, something has been done to overcome that handicap and to spread around Germany an aerial encirclement which will be capable in the future of bringing to bear upon her a pressure not only from the Mediterranean direction but also perhaps from other directions.

II. AIR TACTICS

I turn now to the tactical side of the air war in the West. Tactics are a subject on which for obvious reasons there is need for reticence, and it is only possible to refer here to those aspects which must inevitably emerge in the minds of any thoughtful critics who study the events. I cannot, then, go into details of the formation patterns employed by the Royal Air Force and into the numerous changes in them that have been made as a result of war experience. There are a few things which experience has taught, however, and which may be mentioned as pointing the way to future developments.

The great tactical problem of the moment is concerned with the use of larger numbers of machines. As has already been pointed out, the United Nations are beginning to enjoy the benefits of their superior industrial resources. But they cannot enjoy those benefits to the full unless the technique of using large numbers of aircraft in battle is fully understood and applied.

In 1914-18, air fighting was a matter of individual combat. When large formations met they immediately broke up into numerous atoms, each consisting of two units revolving round one another on tactical orbits. At the start, the fighting in the present war was on much the same lines. Big formations were used. But when these clashed in battle they immediately broke up and scattered into paired atoms, with the outcome dependent upon individual skill and individual technical merit. In 1942, however, it began to become obvious that a further stage must be visualized in aerial tactics and that means must be devised for holding together a large formation so that it could fight as a formation and not as a group of individual units. Some progress has been made in this direction, but more than that cannot just now be said.

Other tactical developments concern the use of low-level attacks, the use of dive bombers, and the use of high-flying aircraft. Low-level attack includes dive bombing and machine-gunning and cannon fire, and it covers such different operations as assaults upon tanks and transport and intruder patrols at night by fighters. The dive bomber has not received the favor of the Royal Air Force, which has always thought that the so-called "fighter bomber" could do all that the dive bomber can do, and with less risk. In this my personal opinion diverges from the official opinion, but I do not intend to press the point here. I shall only say that the fighter bomber has done remarkably fine work in the western desert and in Northern France. The Hurricane in various modified forms can attack targets from a low level with the fire from four cannon or with two 250-pound bombs. It could be made to carry two 500-pound bombs in certain cases. After delivering its attack on whatever ground target has been selected, it still retains its powers as a fighter and therefore has a fairly good chance of making its escape. Hurricanes have been singularly successful in this work. They have been used both by night and by day, and they have conducted innumerable operations against enemy transport in France as well as against enemy gun positions and other targets. Their losses in this work have been low. The North American Mustang has also been working on similar lines with equal success. The Army Coöperation Command of the Royal Air Force has used this machine extensively and has found it well suited to the rigorous conditions under which it functions. Low-level work has been shown to need not only aircraft especially adapted to it, but also especially trained personnel. For example, the demands made upon the pilot of a Mustang making an attack at treetop height on a German position in France differ sharply from those made on the pilot of a Spitfire meeting the enemy at 30,000 feet. The use of ground contours for giving cover right up to the moment of attack has been studied by the Royal Air Force Army Coöperation Command, and those who have been privileged to witness demonstrations by this Command know that formations of low-flying machines are able to approach their target not only unseen but often unheard until they are within short range. Presumably the correct use of the ground contours has some screening effect upon the sound of the machine as well as in making it invisible. The attacks made on railway locomotives in Northern France have largely been conducted by cannon-carrying fighters, which have sufficient accuracy of aim to strike the locomotives and are then able to make good their escape.

The last of the tactical considerations to which I would direct attention concerns high flying. The Junkers 86P stratosphere bomber has been reported over England on at least one occasion, and two or three machines of this type have been shot down in the Mediterranean zone by specially lightened Spitfires. The Junkers 86P is still, at the time of writing, something of a mystery. It is believed to have a pressure cabin for the crew and to have a relatively low maximum speed. It has been reported on several occasions at over 40,000 feet, though whether this figure can be relied upon has yet to be settled. There can be little doubt, in any case, that the 86P marks the opening of an era of high-flying work which was foreshadowed by the operations of the Boeing Fortresses when they first went into action on the western front in the hands of Royal Air Force pilots, and which received fresh emphasis by the truly magnificent achievements of the United States Army pilots later in the year. The Royal Air Force sorties were made with the early model Fortresses which had comparatively little armament protection. In consequence, they relied almost entirely upon height and speed for performing their work and then returning home undamaged. On some occasions they were challenged by enemy fighters and were considerably shot about in the ensuing combats. But they did show that a proper use of height might extend the range of bombing operations. Good vertical visibility is essential for effective bombing from 35,000 feet, and it is not found often over the western front.

The progress made with the stratosphere bomber has led inevitably to more attention being concentrated upon the fast-climbing, high-flying fighter. Here we can distinguish two separate lines of development. The first, favored mainly by United States constructors, is founded upon the turbo-blower, which gives the engine good performance at height. The British line of development, though it also takes account of the special virtues of the turbo-blower, has so far been mainly concentrated upon the mechanically driven supercharger. The Rolls-Royce Merlin 61 engine has been in service for some time, although it was only announced publicly by the Air Ministry in November 1942. This has a two-speed, two-stage supercharger with inter-cooler, and although I am not in a position at the moment to give precise figures I can say that it provides remarkable high-level fighter performances. It goes with the four-bladed airscrew in the Vickers-Armstrongs Spitfire 9.

In the tactical field, then, the things we note in particular are the development of low-flying attack, the development of extremely high-flying methods, and the development of close support bombing, whether by power glided bombers, dive bombers or level bombers. Formation work tends all the time towards the more efficient utilization of large numbers of aircraft at the same time. These are the things which stand out. The technique of individual combat does not show any marked development. Indeed it resembles very closely that of the war of 1914-18.

III. TECHNICAL DEVELOPMENT

I have already said something about the war of high-flying aircraft, a field in which we shall unquestionably see considerable technical development in the future. At present the chief problem is to provide protection for the crew. The pressure cabin seems the obvious solution, but it also introduces certain difficulties. One of the principles of the Royal Air Force is that the pilot should always be given a fair chance of escaping. Consequently the pressure cabin in aircraft capable of flying in the stratosphere would not be considered completely satisfactory unless the pilot were provided with a portable means for sustaining life in the event that he had to bail out and until his fall brought him down to air sufficiently rich in oxygen. It may be recalled that the world's height record flights were made by British pilots around 1937, when heights of nearly 54,000 feet were attained. These were accomplished with a Bristol monoplane with a closed but unpressurized cockpit. The pilot wore a form of diving suit which was maintained at a sufficient pressure during the whole of the flight. The same scheme was followed by the Italian flier, Mario Pezzi, when he reached 55,490 feet in 1938. For war purposes, however, there are obvious defects in the pressure suit, among them the fact that it so encumbers the wearer that he is unable to manipulate his guns or other equipment efficiently. We may assume, therefore, that the pressure cabin must inevitably be the final answer to high-flying problems. And in fact this form of cabin has been in extensive use and a good deal of information about it is already available.

Now let us see whether there are any outstanding trends in the low-level machines. Here we find that the one thing coloring all progress is increase in power. The Hawker Typhoon, which frequently has been mentioned in the news, though at the time of writing it has never been officially mentioned as having been in action, appears to be a comparatively big aircraft for a single-seater. It is powered by the 24-cylinder Napier Sabre engine, which gives a good deal more than 2,000 horse-power. Here we have the trend epitomized: an enormous increase in power and the maintenance of as small-sized a machine as possible. A consequence of this form of development is that wing loadings are tending to rise. At the moment there seems to be no limit in sight to this development. Fighters and bombers are operating at steadily increasing wing loadings. This entails a reduction in the powers of manœuvre, since the turning circle of an aircraft increases in radius as the wing loading goes up. But the advantages in speed are held to outweigh the disadvantages in manœuvre. And in fact designers of the latest types of machine concentrate rather upon speed and climb than upon manœuvre.

There is always a possibility that a higher degree of specialization will prevail among fighters in the future and that some types will be set aside for high-altitude work and other types for low-altitude work. If that occurs, we may expect to see the high-altitude aircraft having a high aspect ratio and perhaps a slightly lower wing loading than the others; but this is sheer speculation. The existing trend is to produce good all-round fighters and then, if the need develops, to modify them for any special duties. The enemy did this with the Messerschmitt fighter. In its original form (109E) it had square-cut wing tips and heavy armament. In the later form, the 109F, the armament was slightly reduced in order to cut weight, and rounded wing tips were provided so that the aspect ratio was increased and the aircraft's performance at height improved. The difference in altitude performance was not very great, according to the calculations which have been placed before me. Nevertheless the incident does show how much importance attaches to giving a fighter pilot just sufficient performance to allow him to have a fighting edge over his opponent.

It is more difficult to make a few simple generalizations about bomber design than about fighter design. One school adheres to the view that the most important thing in bombers is speed, and that provided a load of 2,000 pounds can be carried the whole of the remainder of the design effort should be devoted to giving high speed. The de Havilland Mosquito can be said to epitomize this view. On the other hand, the Avro Lancaster, though much slower than the Mosquito, carries a much greater load. It also has four power-operated turrets whence it can bring fire to bear in almost any sector. The question really is, then, whether the Lancaster is fast enough to bomb without heavy losses by day and by night. If it is, then obviously economies can be effected in the crew required per thousand tons of bombs dropped. Modern interception methods are so highly developed that in the daylight without cloud cover any aircraft, however fast, can hope only rarely to penetrate enemy defenses without being tackled by fighters. Thus daylight bombing appears to require some altogether novel solution. One possibility has been presented by the United States Army Air Force in Britain, whose Boeing Fortresses have relied upon their great fire power to beat off attack. But if the aircraft in question are to penetrate any great distance into enemy territory this method means that they must carry huge supplies of ammunition. The problems of the long-range fighter have not yet been satisfactorily solved, for as the range of the fighter goes up so its speed and climb performance go down, which means it is no better placed for tackling the enemy's defending fighters than the high-speed bomber.

In conclusion, I may say of air operations in the West at the close of 1942 that the United Nations might be considered to be engaged in an enormous encircling movement. Air bases encircle the enemy along the North African coast, up through Syria, along the Russian front, and (with a gap) back through Iceland and Great Britain. A sufficiently great aerial striking power will enable the United Nations to come in and attack on any point in that circumference. For this they will need the mobility which might be supplied by air transport on a large scale. They therefore must develop to the limit the troop transport aircraft, the troop transport glider, the supplies machine and parachutists. They must then press forward with the task of increasing by all possible means the range of all types. Finally, they must retain a sufficient technical superiority in short-range fighters so that they can hold the bases which they have secured against all possible attacks and so that they can cover their essential supply of operations wherever they may be.