Chapter 22: Review of Air Operations
Before trying to form an appreciation of the part played by British forces in this campaign it may be well to look back over the accounts of air operations and to bring these together in a brief summary, for it is less easy to trace their course and their effect in the day-to-day story then it is to follow the actions and outcome of land fighting. Moreover the operations of the Royal Air Force involved not only air forces stationed in France—the Air Component of the British Expeditionary Force and the Advanced Air Striking Force—but also home-based squadrons of Bomber, Fighter and Coastal Commands. The air campaign was fought both in France and from England: in that regard it differed widely from the land campaign.
The course of air operations may be divided conveniently into four phases.
In the first phase, extending from May the 10th to the 15th, the Air Component, enlarged progressively by the equivalent of ten additional fighter squadrons, fought successfully to aid and protect the British Expeditionary Force during its move forward to the Dyle. At the same time the Advanced Air Striking Force engaged in intensive attacks on the enemy’s advancing armies, and suffered grievous loss in doing so. In these attempts to delay the German advance, squadrons of Bomber Command based in England joined both by day and by night. Air reconnaissance also played an important part in the operations in these opening days.
In the second phase, lasting from May the 16th to the 22nd, the Air Component was further strengthened by six fighter squadrons operating from English bases. I was chiefly engaged in checking the enemy’s air attacks where a final breakthrough to the coast threatened. When that threat became a reality and our northern airfields were endangered or overrun, the Air Component was brought home to continue the fight from England.
During the opening days of this phase the airfields of the Advanced Air Striking Force were also endangered and its squadrons were compelled to move further south. Thereafter they continued the bombing of enemy columns moving up to the battle, but by night only, for their losses by day were too heavy. But the squadrons of Bomber Command, which were equipped with more suitable aircraft, continued similar attacks both by day and night and in addition engaged in strategic bombing of targets in Germany.
Fighters of the Advanced Air Striking Force were at this time primarily occupied in defence of our airfields, in offensive patrols over the French front on the Aisne and in the protection of reconnaissance sorties.
The third phase of air operations extended from May the 23rd to June the 4th. Although what remained of the fighters of the Air Component had moved to England, the contribution of Fighter Command was greater than ever. It was in these days that the squadrons of No. 11 Group fought their great battle with the Luftwaffe above the army withdrawing to the coast and to England—the battle which spoiled Goering’s plan to prevent evacuation.
Fighters of the Advanced Air Striking Force, during these days, also flew offensive patrols over the southern portion of the battlefield to counter German dive-bombing, particularly on the positions of the French Army. They had also to give cover for day bombing and to protect the airfields in use by our air forces in France. The bomber squadrons of Air Striking Force continued by night their attacks on enemy reinforcements and supplies, while by day squadrons of Bomber Command based in England gave support to the withdrawing armies by attacking the enemy’s columns, transport and communications.
In the final phase, from June the 5th, when the enemy’s southward offensive opened, till the French armistice brought the campaign to an end, the Royal Air Force concentrated on attempts to help our few remaining divisions in France and the hardly pressed French armies. For the latter task all the medium bombers of Bomber Command (No. 2 Group) were placed at the disposal of Air Marshal Barratt, who worked throughout in close concert with the French High Command. They attacked the enemy’s troop concentrations, forward supply depots, river crossings and communications while fighters gave them cover and flew offensive patrols. Two additional fighter squadrons were sent out, but as the French Army’s resistance was broken it became progressively impossible to coordinated air attacks and land defence. When the end approached, what remained of the Advanced Air Stroking Force was brought home, only the five fighter squadrons (two of them based on Jersey airfields) remaining till the very last to cover evacuations from southerly harbours.
With this outline of operations in mind and with a knowledge of the course taken by land operations it is possible to appraise more clearly the parts played by the Royal Air Force—to realise the nature and extent of their operations and the measure of their achievement.
Britain could not have employed larger land forces in this campaign, for in the time available we sent to France practically all we had; the undertaking given in 1939 was more than fulfilled. How far is it true that, similarly, we employed all that was available of our
air strength? Obviously it was right to keep some for the air defence of Great Britain. The question is therefore one of proportion. What proportion of our air strength was kept in hand for the latter purpose? That question is easy to answer for it is a plain question of fact.
On May the 10th the total number of first-line aircraft in the Royal Air Force was 1,873. Of these 416 were stationed in France. When the fighting began the number in France was at once increased. Subsequently forces of circumstances compelled some to move to England, but the number of squadrons stationed in France bore no significant relation to the total air strength employed. The first was dictated by events, the second by British air policy.
When war was declared the Air Staff and the Government knew that the Royal Air Force must face great odds. Their initial air policy was framed accordingly, but as operations progressed they were beset by British, French and Belgian demands for additional help, on all sides and in every sort of task. If an attempt had been made to meet all demands without regard to a general air policy, the Royal Air Force, as then organised, must have been virtually destroyed.
Two major questions of policy exercised the judgement of the Air Staff and the War Cabinet throughout the campaign. How could our bombers be used to inflict the greatest damage on the enemy? How many of our fighters could be used without undue damage to our home defence? Considerations which shaped the decisions taken on these two questions of grand strategy belong to other volumes of this history but their result is traceable in air operations and especially in the operations of our bombers and fighters.
Bombers are essentially offensive weapons and, whether or not they were used in the best way, all that we had were used. None of our striking power was held back. In addition to the squadrons of the Advanced Air Striking Force, the whole strength of Bomber Command was continuously employed.
From the summary of operations outlined above, it is clear that bombers were engaged in five sorts of operations, namely:
1. daylight attacks by medium bombers of the Advanced Air Striking Force stationed in France, and of Bomber Command’s No. 2 Group stationed in England, against enemy columns, concentrations and communications;
2. night attacks by bombers of the Advanced Air Striking Force against enemy concentrations and communications west of the Rhine’
3. night attacks by heavy bombers of Bomber Command’s Nos. 3, 4 and 5 Groups against enemy concentrations and communications west of the Rhine;
4. night attacks by bombers of Nos. 3, 4 and 5 Groups against enemy concentrations and communications east of the Rhine;
5, night attacks by Nos. 3, 4 and 5 Groups against oil plants in Germany.
There were, in addition, subsidiary bombing attacks on enemy airfields, headquarters and battery positions, and operation ‘Royal Marine’ in which the Rhine was sown with drafting mines.
Later in the war we could use as many as 1,000 far heavier bombers than any we had in 1940 to attack a single target on a single night. In May 1940, the Royal Air Force had only 544 bombers of all types for all the operations listed above. To estimate the damage they did by the standards of later years would be meaningless. It is better to measure their strength against the task which they were set.
For daylight tactical attacks in the opening phase the Advanced Air Striking Force had but ten squadrons of medium bombers—eight of these being the ill-suited Battles. Their task was to hinder the German armies advancing through country which reached from the North Sea to the Meuse and soon extended from Germany to the English Chanel. The points they were to attack by day were those of most importance to the enemy and therefore those most strongly defended: by night they were to bomb bridges and other targets which were hard to distinguish and harder still to hit. Seen thus against the background of German operations, the gallantry of their effort stands vividly displayed, but it is clear that the damage they inflicted could be little more than temporary. The medium bombers of Bomber Command were better suited to daylight bomber, but their effective use in collaboration with ground forces was a handicapped by the exercise of control from England, at a time when communications were roundabout and slow.
Division of opinion as to how our heavy bombers should be used—whether, that is, they should be confined to the strategic bombing for which they were designed, or whether they, too, should be used to assist the Allied armies in their fighter to stem the German advance—resulted in compromise. They were used for both tasks and so were unable to concentrate on either.
Strategic bombing of military targets in German was not authorised by the War Cabinet until May the 15th. As a matter of Allied policy, therefore, Germany enjoyed immunity from air attack not only while she defeated Poland and throughout winter and spring, but for the first five critical days of her western offensive. Once the bombing of German targets was authorised our heavies began night attacks on oil plants and marshalling yards east of the Rhine. But after three nights part of the heavy bomber force was taken off these tasks and, and in order to assist the Allied armies, was directed to attack enemy concentrations and communications behind the battlefront, that is, west of the Rhine. From then on until the Dunkirk evacuation
was completed the main strength of our heavy bomber force was devoted to this behind-the-battle bombing; only on six nights was a small proportion devoted to attacks on oil plants and railway marshalling yards. After Dunkirk the heavy bombers were again concentrated on oil—but only for one night. With the opening of Germany’s new offensive all were again devoted to attacks on enemy concentrations and communications behind the battlefront.
The object of bombing strategic targets in Germany was a four-fold one, namely:
1. to reduce the enemy’s total resources of oil;
2. to disorganise his lines of communication, especially railways on which he must rely for long-distance supply of his armies;
3. to compel his to hold back from the battle fighter for home defence;
4. to divert his bombers from France by inducing retaliation on England.
None of these results was obtained. The attack on oil plants was not heavy enough to inflict seriously damaging loss, and in any case it is now known that German oil resources were underestimated. The attack on the enemy’s lines of communication was not sufficiently sustained to prevent the comparatively quick repair of damage done. The German air force was not diverted from its task of collaboration in the land campaign; only after the French armistice did the Luftwaffe turn from France to make serious attacks on England. In fact it is clear that our bomber force was not nearly strong enough in 1940 to affect for long the course of large-scale land fighting. Three hundred and thirty-four bombers were lost in the attempt to do so. How far they delayed the final decision cannot be assessed.
It is equally clear that the fighter forces were not strong enough to perform all the tasks that were asked of them. The fighter is a defensive weapon only in the sense that attack is the best method of defence—its aggressive name well describes its character. It is designed to protect from air attack by fighting the enemy’s aircraft wherever they are found—’to cleanse the sky’. In 1939 the Air Staff calculated that sixty squadrons were needed to defend Great Britain, but when the German offensive began we had only fifty-three and of these six were in France, four more were to be sent there as soon as fighting started, and two were earmarked for Norway. Only forty-one squadrons remained then for home defence—two-thirds of what were needed. Nevertheless the original six squadrons in France were increased to the equivalent of sixteen by the end of the first week’s fighting. On May the 20th what remained of the Air Component fighters in northern France had to be transferred to fight from English airfields, but this did not reduce the number we employed,
for there they were augmented by the squadrons of No. 11 Group. As the battle in France neared the coast, and throughout the nine days of evacuation, squadrons were almost continuously engaged. After Dunkirk, when the new German offensive began, the three squadrons with the Advanced Air Striking Force were increased to five, while squadrons in England again joined in the fighting which was within their range after refuelling near Rouen. During the course of the campaign forty-three fighter squadrons were engaged—only ten of the fifty-three squadrons which we had when fighting started we, in the end, not used in the campaign, and of those two were based in Norway, three were night-fighters and two were re-equipping and non-operational.
The tasks which fighters were asked to perform were exacting:
1. to protect our own troops and our Allies from enemy air attack;
2. to defend their own airfields and other bases and key positions from enemy bombers;
3. to protect our own aircraft in their bombing attacks and reconnaissance;
4. to protect troops and shipping during evacuation.
The squadrons employed could not possibly do all these things everywhere and at all times. Neither the Army, nor the Navy, nor our Allies had the measure of protection for which they looked (though they had more than they always realised), for the fighter forces employed were not numerically strong enough to keep the Luftwaffe at bay. But, again, what was done should be measure against some theoretical or desirable standard but against the magnitude of the tasks set.
In the first ten days they gave effective cover to the British Expeditionary Force as it advanced to the Dyle and withdrew, fighting to the Escaut, but of 261 Hurricanes employed in these operations only sixty-six remained when the Air Component was transferred to England. In addition, fighters of the Advanced Air Striking Force did all they could to protect the medium bombers in their daylight attacks. In the fighting to cover evacuation from Dunkirk, the squadrons of Fighter Command played a splendid part, setting out day by day to find and fight an enemy in greater strength. Had the Luftwaffe been allowed to circle unhampered over Dunkirk, as it had done over Warsaw and Rotterdam, evacuation might well have been stopped. Instead German reports constantly record our fighters’ interference and only in two days out of nine could the Luftwaffe seriously hinder the Navy’s work. If our fighters could not do all that the Army and Navy wished, they helped substantially to make evacuation possible. As mentioned above, all but ten of our total fighter squadrons were engaged. They lost 474 aircraft—more than half the
total number of fighters with which we had started operations on May the 10th.
Unlike some of the bombers that were unsuited to the operations which they had to undertake, the Hurricane and Spitfire fighters proved their excellence. They enabled our pilots to fight with success enemy formations of greater numerical strength and in individual combat (which the Luftwaffe sought to avoid) to obtain a confident mastery.
Nearly half of the total aircraft available to Coastal Command were also employed in the campaign. The first task of Coastal Command was to patrol the sea which surround Great Britain in order to give early notice of enemy surface ships, U-boats and E-boats using these waters or approaching our shores and to protect our shipping convoys in home waters. The responsibility for this coastal protection (which included torpedo or bombing attacks on enemy ships) was divided between three groups of which No. 16 Group (covering the coastal area from, roughly, Flamborough Head to Weymouth) was chiefly concerned. Throughout the campaign an arduous series of patrols over the English Channel and the North Sea was maintained and when evacuation was in progress the five squadrons of the Group were strengthened by the attachment of squadrons from No. 18 Group and from the Fleet Air Arm. Coastal reconnaissance, the protection of ships engaged on evacuating troops, and collaboration with Fighter Command in covering, first, the Dunkirk bridgehead and, later, other evacuation ports on the west coast were then their principal tasks; but minelaying operations and attacks on the enemy’s coastal batteries and other land targets were also undertaken in response to specific requests by the Admiralty.
Coastal Command’s No. 16 Group, with additional squadrons under its command, had an average daily total of seventy-three aircraft available in May, 1940, rising to ninety in June. During the campaign forty-six were lost or irreparably damaged.
To completely the overall picture of the part which the Royal Air Force played in this campaign it is necessary not only to show the magnitude of the task which it attempted but also to realise the difficult circumstances in which it fought.
The Government’s pre-war conception of what would be the role of our air forces in a war with Germany required the Royal Air Force to plan accordingly. When war was declared and an army was sent to France, it was still believed that the Allies could remain on the defensive till their forces were built up. In such a war their primary tasks would have been the maintenance of increasingly heavy and sustained attack on strategic targets in Germany, the provision of air protection for troops who held the front, and the air defence of Great Britain. For these tasks they prepared—not for a war of rapid movement.
When the French front was broken and a war of movement was forced on the Allies, the Royal Air Force was required to devote a major part of its strength to the assistance of Allied land forces, a task for which it had not been primarily designed, equipped or organised.
Much less had it been case to play such a role in a long, fighting withdrawal, when it was necessary to adjust plans frequently and to change bases in conformity with a rapidly changing situation on the ground; when it was difficult to maintain the quick communications which alone make possible effective collaboration with land forces; when transport was short, airfields inadequate, and the means to lay down temporary air strips had not yet been devised; and when the enemy’s advance had cut the Allied armies in two and the command of air operations had in consequence to be divided.
These were the circumstances in which the Royal Air Force had to fight in this campaign. And though it did much damage to the enemy and contributed notably to the salvation of the British Expeditionary Force, it could not otherwise greatly affect the course or outcome of the battle in France. It took a good toll of German aircraft and pilots and to that extent weakened the blow which the enemy delivered subsequently in the Battle of Britain. That it did not accomplish more was due to the fact that preparation for a possible war with Germany had been based on a strategic conception which was radically at fault.
Fighting under this great initial handicap, the Royal Air Force showed again the courage and skill of its pilots and the excellence of their latest type of fighter aircraft. And it gained experience which proved to be of great value in later and more successful campaign.