Operation Sealion

Posted on Friday 6th July 2012

Extracted from The Narrow Margin by Derek Wood and Derek Dempster and reproduced by permission of Pen and Sword Books Ltd.

On the morning of 4 June 1940, Generaloberst Milch flew his personal aircraft to Dunkirk and surveyed the smouldering ruins left after the evacuation. He was surprised to see the enormous quantities of war material which choked the roads and the beaches. It was clear that the British Army had abandoned nearly all its tanks, guns and motor vehicles.

The rapid progress across France made by the German Army in the next ten days convinced Milch that an immediate effort should be made against Britain while the island’s defences were still disorganised and the RAF was in the process of re-forming.

There they were to take and hold key fighter airfields such as Mansion and Hawkinge and be reinforced by normal troops taken over by air in second or third waves. Stuka formations were to provide the artillery support and both Stukas and Me 109s were to be operated from the airfields as soon as they had been cleared. While Ju 52s maintained supplies of ammunition, fuel and food German ground troops were to be ferried across the Channel in any and every available ship. Milch envisaged that Luftflotten 2 and 3 would transfer the whole of their effort from the French front to the British coast. The plan involved considerable risk, but it might have succeeded.

At that time British ground defence was almost non-existent. At the worst, the troops would be lost, but such would have been the confusion and destruction in Britain that the air war might have been won in 1940. The start of widespread air attack in mid-June would have allowed no rest for Fighter Command and an extra month’s good weather for the Luftwaffe. Göring’s reaction was one of blank amazement and he described Milch’s suggestions as ‘nonsense’. Putting such unpleasant thoughts out of his mind he prepared to enjoy the pleasures of Paris in the early summer. One of the most unusual opportunities in German military history had been thrown away.

To the British public the failure of hordes of German paratroops, fifth columnists and waves of black-crossed bombers to arrive came as a distinct surprise. For nearly 900 years the ‘sea-girt isle’ had been inviolate. Now a powerful enemy was on the doorstep and from the Army point of view the country was naked on the ground. There were not even enough rifles to equip regular troops let alone the newly formed Local Defence Volunteers. Only the Royal Air Force and the Royal Navy remained to challenge Hitler’s might. The assault was awaited hourly but none came. For over a month, apart from a few night raids, the Luftwaffe stayed away. The sea-borne landing preparations were not completed until September, then to be shelved permanently.

In June 1940 it seemed to Germany and to many in authority in neutral countries that the sun was setting on Britain and her Empire and that the end was only a matter of time. Apart from poor intelligence services the German Government suffered from a complete lack of knowledge of the British way of life and character. This was to cost them dear. Neither Göring nor Hitler had been to the United Kingdom and they did not speak English. While Mein Kampf and other inter-war documents showed a marked respect on the Führer’s part for the British nation, his regard for its military potential deteriorated rapidly from the time of the Munich crisis.

Fieldmarschal von Brauchitsch, Commander-in-Chief of the German Army discusses the invasion of England with senior officers on the French coast.

Chamberlain’s performance in 1939 and a great deal of pacifist oratory and scribbling led him to believe that the vitality and morale of the British had been undermined. Having no personal knowledge, Hitler came to believe that Britain was still run by aristocracy on a feudal system and that the legally elected House of Commons was in constant danger of being overthrown. Hitler, believing that Britain would sue for an armistice, decided to finish France immediately after Dunkirk. Accordingly, his main forces were switched to the area between the Somme and the Aisne. The decisive battle opened on 9 June, and by the 14th Paris had fallen. On the 17th the Petain Government asked for terms and the historic railway carriage at Compiegne was used for the signing of the armistice as it had been by the Allied victors in 1918. From 22 June to 29th Hitler went sightseeing in France and the OKW free-wheeled for the period. This was an extraordinary procedure if a swift end to the war was to be brought about by military means.

Following a somewhat nebulous directive from the Führer on 26 May which granted ‘unlimited freedom of action’ to the Luftwaffe to attack England when suitable strength had been built up, preliminary planning for an air assault began.

Five days after the conclusion of the Franco-German Armistice, on 30 June 1940, Göring issued a general order regarding the air war against the island fortress. In it he stated:

The Luftwaffe war command in the fight against England makes it necessary to co-ordinate as closely as possible, with respect to time and targets, the attacks of Luftflotten 2, 3 and 5. Distribution of duties to the Luftflotten will, therefore, in general be tied to firm targets and firm dates of attack so that not only can the most effective results on important targets be achieved but the well-developed defence forces of the enemy can be split and be faced with the maximum forms of attack.

After the original disposition of the forces has been carried out in its new operational areas, that is after making sure of adequate anti-aircraft and fighter defence, adequate provisioning and an absolutely trouble-free train of command, then a planned offensive against selected targets can be put in motion to fit in with the overall requirements of the commanders-in-chief of the Luftwaffe. To save us time as well as ensuring that the forces concerned are ready:

(A) The war against England is to be attacks against industry and air force targets which have weak defensive forces. These attacks under suitable weather conditions, which should allow for surprise, can be carried out individually or in groups by day. The most thorough study of the target and its surrounding area from the map and the parts of the target concerned, that is the vital points of the target, is a pre-requisite for success. It is also stressed that every effort should be made to avoid unnecessary loss of life amongst the civil population.

(B) By means of reconnaissance and the engagement of units of smaller size it should be possible to draw out smaller enemy formations and by this means to ascertain the strength and grouping of the enemy defences. The engagement of the Luftwaffe after the initial attacks have been carried out and after all forces are completely battle-worthy has for its objectives:

(a) By attacking the enemy air force, its ground organisations, and its own industry to provide the necessary conditions for a satisfactory overall war against enemy imports, provisions and defence economy, and at the same time provide the necessary protection for those territories occupied by ourselves.

(b) By attacking importing harbours and their installations, importing transports and warships to destroy the English system of replenishment. Both tasks must be carried out separately, but must be carried out in co-ordination with one another.

As long as the enemy air force is not defeated the prime requirement for the air war is to attack the enemy air force on every possible opportunity by day or by night, in the air or on the ground, without consideration of other tasks.

This, therefore, was to be the German plan of campaign: build up the airfields and facilities in France, Belgium and Holland; sound out the defences by using fighters with small bomber formations and then throw the full weight of the Luftwaffe into the destruction of the RAF and its resources including the aircraft industry. Harbours and similar installations were to be attacked simultaneously to cut off vital imports from abroad.

The pattern was to be exactly as in Poland, Belgium, Holland and France – the destruction of the enemy air force at the outset in the air and on the ground.

The overall strategic plan was simple. Once RAF Fighter Command had been defeated, the Luftwaffe could overcome the superior strength of the Royal Navy in the Channel. The slow trains of barges etc would then have faced only the British Army and coastal defences. Once through these, with one or two airfields occupied, then the Luftwaffe could operate from British soil and range far and wide over the country.

The invasion could not be launched until Fighter and Bomber Commands had been smashed.

Photographs coloured by Jon Wilkinson.