German aircraft continued to make occasional “pirate” raids on factories and other objectives in, the Spring, but thereafter activity by day, apart from operations against shipping, consisted almost entirely of reconnaissance flights and occasional “tip-and-run” attacks on coast towns in England and Scotland. Offensive operations by German fighters virtually ceased in the early Summer. On a few occasions – in the Autumn Me 109 fighters were seen over Kent and Sussex, but the only offensive action worthy of the name which was taken by German fighters in the second half of 1941 was on Christmas Day, when two aircraft appeared off the South Coast and opened fire on buildings near Hastings. This was the prelude to a new low-level fighter and fighter-bomber offensive which was to take place in 1942.
The interception of “pirate” raiders and other aircraft flying singly was a difficult task, especially in cloudy weather, when problems arose similar to those which surrounded night interception. As early as December 1940, the principle of using Beaufighters fitted with A.I. by day in bad weather was established, and as experience grew it became evident that in such conditions the only reasonable chance of success was offered by the same combination of A.I. in the aircraft, and G.C.I (Ground Control of Interception) on the ground, as was used at night.
The next step was the use of G.C.I, by day for controlling fighters without as well as with A.I. In August 1941, I made provision for this to be done throughout Nos. 10 and 11 Groups, although at this stage G.C.I. Stations in No. 11 Group were not required to keep watch by day in good weather.
Another step taken about this time was the development of a plan for intercepting aircraft capable of flying at very great heights, which it was thought that the Germans might be planning to use against us. After fighters of No. 10 Group had practised making very high-altitude G.C.I, interceptions of [Boeing] Fortresses of Bomber Command, my staff devised a system of control whereby the country was divided into a number of regions each-containing an “area control” connected with a “central control” designed to co-ordinate their activities. This scheme was to prove useful in 1942 when the Germans sent a number of high-flying [Junkers] Ju 86 P reconnaissance aircraft over this country.
With the decline in the volume of overland activity by the Luftwaffe towards the end of 1941, I considered it reasonable to contemplate a relaxation of the principles of balloon barrage control which had been re-affirmed in the spring. Technical improvements which made it possible to raise balloons to their operational height more quickly than hitherto favoured a change which seemed called for by an increased volume of flying by our own aircraft, to which the barrages were in some circumstances an impediment. In November trials were made with a system whereby a large number of provincial barrages were grounded throughout the 24 hours except when German aircraft were known to be about. It was not until 1942, however, that this system was finally adopted.
Offensive Operations up to 13th June, 1941
Pilots of No. 71 Squadron in front of the Hurricane Mk. II. By 1941, the Hurricane was rapidly approaching obsolescence in the day fighter role, and converting first-line fighter squadrons to Spitfires became a matter of priority. No. 71 received their first Spitfires Mk. IIa in August 1941.
During the Battle of Britain the initiative in daylight operations lay with the Germans. Nevertheless, even before the battle was over a time was foreseen when our fighter squadrons would seize the initiative and engage the German fighters over the far side of the Channel. The necessary operational instructions were drawn up as early as the third week in October, 1940, and revised in the first week of December.
By the latter date it was possible to contemplate something more ambitious than a mere pushing forward of fighter patrols, and on 29th November, I instructed the Air Officer Commanding No. 11 Group [Leigh-Mallory] to look into the possibility of combining offensive sweeps with operations by Bomber Command.
In the middle of December the German fighter force, which had suffered heavy losses since the summer, virtually abandoned the offensive for the time being. Clearly, the moment had come to put our plans into effect and wrest the initiative from the enemy.
Broadly speaking, the plan which we now adopted visualized two kinds of offensive operations. In cloudy weather, small numbers of fighters would cross the channel under cover of the clouds, dart out of them to attack any German aircraft they could find, and return similarly protected. In good weather fighter forces amounting to several squadrons at a time, and sometimes accompanied by bombers, would sweep over Northern France. The codenames chosen for these operations were respectively “Mosquito” (later changed to ”Rhubarb” to avoid confusion with the aircraft of that name) and “Circus”. In practice it was necessary to restrict the name Circus to operations with bombers, and fulfilling certain other, conditions which will become apparent as this account proceeds.
Rhubarb patrols were begun on 20th December, 1940, and provided valuable experience alike for pilots, operational commanders, and the staffs of the formations-concerned. I encouraged the delegation of responsibility for the planning of these patrols to lower formations, and many patrols were planned by the pilots themselves with the help of their Squadron Intelligence Officers.
It was obvious from the start that in many cases pilots engaged on these patrols would not succeed in meeting any German aircraft, and they were authorised in this event to attack suitable objectives on the ground. Nevertheless, I considered it important that the primary object of the operation – namely, the destruction of enemy aircraft – should not be forgotten, and discouraged any tendency to give undue emphasis to the attacks on ground objectives.
Between 20th December, 1940, and 13th June, 1941, 149 Rhubarb patrols, involving 336 sorties, were flown, of which 45 were rendered abortive by unsuitable weather or other extraneous circumstances. German aircraft were seen in the air on 26 occasions, to a total of 77 aircraft, and on 18 occasions were engaged. The destruction of seven enemy aircraft was claimed for the loss of eight of our pilots, and 116 separate attacks were made on a variety of surface objectives, including ships, road vehicles, airfield buildings, grounded aircraft, artillery and searchlight posts, German troops and military camps.
Rhubarb operations proved highly hazardous and inflicted relatively little damage.
Rudder of a Spitfire damaged by German flak over France, 1941
[State Library of Victoria]
Operations on a larger scale began with a sweep off and over the coast of France by a total of five squadrons of fighters on 9th January, 1941. The first operation with bombers followed on the next day, when dispersal pens serving landing grounds on the edge of the Foret de Guines, South of Calais, were attacked. Altogether eleven of these Circus operations were executed up to 13th June, the objectives for the bombers including the docks at Dunkirk, Calais and Boulogne, a number of airfields and one industrial plant known to be working for the Germans. In addition more than forty sweeps were made during this period by fighters without bombers.
After the first three Circus operations an inevitable difference of view between Bomber and Fighter Commands as to the primary object of these attacks became apparent. The principal aim of my Command was to shoot down enemy aircraft, while Bomber Command, naturally enough, attached more importance to the bombing. It was, however, the view of the Chief of the Air Staff that the bombing of objectives in France with the resources available for operation Circus could have no decisive military effect at this stage of the War, and that it would be a pity to spoil the chances of the fighters by making them conform to the requirements of a bomber force bent exclusively on inflicting material damage by bombing, and prepared to linger over the target area for that purpose. On his instructions, the Air Officer- Commanding-in-Chief, Bomber Command, and myself, held a conference at my Headquarters on 15th February, 1941, when we agreed that the object of operation Circus was to force the enemy to give battle in conditions tactically favourable to our fighters. To compel the Germans to do so, the bombers must do enough damage to make it impossible for them to refuse to fight.
The early Circus attacks were not always successful in producing these tactically favourable conditions, even after agreement on this point had been reached. This was largely because, in practice, there was still a tendency for our forces to operate too low down. There is no doubt that ideally our lowest fighter squadron should never have flown at less than about 18,000 feet, the highest being somewhere about 30,000 feet. To achieve this it would have been necessary for the bombers invariably to fly at 17,000 feet or more. This was, not always practicable, if only because of the time required by the Blenheim bombers then used for these operations to reach that height. Nevertheless, it was thought advisable to lay down this principle as a desideratum, and this was done when I issued fresh instructions for operation Circus during the third week in February. In the next three operations the bombers flew at heights between 15,000 and 17,000 feet and in the following two at 10,000 and 12,000 feet respectively.
Towards the end of May the weather declined, and between 22nd May and 13th June no Circus operations were attempted. Up to this point no major fighter battle had occurred, the enemy having been content, on the whole, to pounce on stragglers or otherwise attempt to exploit any favourable tactical situation which might develop. In the absence of such favourable circumstances he had usually avoided combat. In this sense the operations had proved slightly disappointing. On the other hand, statistically the results were fairly satisfactory so far as they went, the destruction of 16 aircraft and probable destruction of a substantial number of others being claimed for the loss of 25 of our pilots; and much valuable experience had been gained. Moreover, by a combination of Circus and Rhubarb operations our ultimate object, which was to seize the initiative, harass the enemy, and force him on to the defensive, had undoubtedly been achieved.
Besides these Circus operations, fighter sweeps, and Rhubarb patrols, a series of bombing attacks on shipping and what were called “fringe targets” by aircraft of Bomber and Coastal Commands, with fighter escort, were made between 5th February and 12th June, 1941. These operations differed from Circus operations inasmuch as the primary object was not to force enemy fighters to give battle, but to damage or destroy the target. The fighter force therefore conformed to the requirements of the bomber force and did not seek battle unless attacked.
Sixteen such operations were undertaken during the period stated, the size of the bombing force ranging from three to eighteen aircraft, and that of the fighter escort from one flight to eight squadrons. A number of combats with German fighters developed, in which we claimed the destruction of one German aircraft for approximately every one of our pilots lost. A considerable volume of fighter-reconnaissance was carried out in connection with these operations.
A picture full of the atmosphere of the Circus offensive, with two Spitfires Mk. VB of No. 71 Squadron starting their engines prior to another mission over France.