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Old 05-26-2009, 04:29 AM
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Default Operation Sealion

Operation Sea Lion was Germany's plan to invade the United Kingdom during World War II, beginning in 1940. However, to have any chance of success, the operation required air supremacy over the English Channel. With the German defeat in the Battle of Britain, Sea Lion was postponed indefinitely on 17 September, 1940.

Following swift victory in the Battle of France, Germany believed the war in the west was won. However, the United Kingdom refused peace talks. As a result, more direct measures to break British resistance were considered.

Grand Admiral Erich Raeder of the German Navy oversaw numerous studies for a German naval assault across the English Channel. The earliest of these, made around November 1939, identified the conditions for invasion.

The British Royal Navy must be eliminated.
The British Royal Air Force air strength must be eliminated.
British Coastal defences must be destroyed.
British submarine action against landing forces must be prevented

The German Army High Command originally planned an invasion on a vast scale, extending from Dorset to Kent. This was far in excess of what their navy could supply, and final plans were more modest, calling for nine divisions to make an amphibious landing with around 67,000 men in the first echelon and an airborne division to support them. The chosen invasion sites ran from Rottingdean in the west to Hythe in the east.

The battle plan called for German forces to be launched from Cherbourg to Lyme Regis, Le Havre to Ventnor and Brighton, Boulogne to Eastbourne, Calais to Folkestone, and Dunkirk and Ostend to Ramsgate. German paratroopers would land near Brighton and Dover. Once the coast was secured, they would push north, taking Gloucester and encircling London. There is reason to believe that the Germans would not attempt to assault the city but besiege and bombard it. German forces would secure England up to the 52nd parallel (approximately as far north as Northampton), anticipating that the rest of the United Kingdom would then surrender.

Adolf Hitler's initial warning order on 16 July, 1940, reflected the most current thinking and set out the revised minimum pre-conditions. He prefaced his order by stating: "I have decided to prepare a landing operation against England and, if necessary, to carry it out".

Hitler's conditions for invasion were:

The RAF was to be "beaten down in its morale and in fact, that it can no longer display any appreciable aggressive force in opposition to the German crossing".
The English Channel was to be swept of British mines at the crossing points, and the Straits of Dover must be blocked at both ends by German mines.
The coastal zone between occupied France and England must be dominated by heavy artillery.
The Royal Navy must be sufficiently engaged in the North Sea and the Mediterranean so that it could not intervene in the crossing. British home squadrons must be damaged or destroyed by air and torpedo attacks.
This placed responsibility for Sealion's success on the shoulders of Naval High Command Grand Admiral Erich Raeder and Air Force High Command Imperial Marshal Hermann Göring.

Italian dictator Benito Mussolini offered troops, but Hitler declined his offer. However, the Italian Air Corps did participate towards the end of the Battle of Britain.

The aerial battles which resulted from (Operation Eagle) later became known as the Battle of Britain. Adler's objective was for the Luftwaffe to achieve air superiority over the Royal Air Force and allow the German invasion fleet to cross the English Channel. However, the change in emphasis of the bombing from RAF bases to bombing London turned Adler into a strategic bombing operation. This switch afforded the RAF, reeling from Luftwaffe attacks on its bases, time to pull back and regroup.

The main difficulty for Germany was the small size of its navy. The Kriegsmarine had lost a sizable portion of its large modern surface ships in the Norwegian Campaign, either as complete losses or due to battle damage. In particular, the loss of a large portion of their destroyers was crippling. The U-boats, the most powerful arm of the Kriegsmarine, were not suitable for operations in the relatively shallow and restricted English Channel. Although the Royal Navy could not bring to bear the whole of its naval superiority against the Kriegsmarine (most of the fleet was engaged in the Atlantic and Mediterranean), the British Home Fleet still had a very large advantage in numbers. British ships were still vulnerable to enemy air attack, as demonstrated during the Dunkirk evacuation and by the later Japanese sinking of Prince of Wales and Repulse. However, the 22-mile width of the English Channel and the overall disparity between the British and German naval forces made the amphibious invasion plan risky, regardless of the outcome in the air. In addition, the Kriegsmarine had allocated its few remaining larger and modern ships to diversionary operations in the North Sea.

The French fleet, one of the most powerful and modern in the world, might have tipped the balance against Britain. However, the preemptive destruction of the French fleet by the British by an attack on Mers-el-Kébir and the scuttling of the French fleet in Toulon two years later ensured that this could not happen.

Even if the Royal Navy had been neutralised, the chances of a successful amphibious invasion across the channel were remote. The Germans had no specialised landing craft, so their transports were primarily river barges. This would have limited the quantity of artillery and tanks that could have been transported, and restricted operations to times of good weather. The barges were not designed for the open sea and even with almost perfect conditions, their progress would have been slow and the craft vulnerable to attack. There were not enough barges to transport the first invasion wave nor the following waves with their equipment. Without adequate landing craft, the Germans would have needed to immediately capture one of the ports, an unlikely scenario considering the strength of the British coastal defences around the south-eastern harbours at that time. The British also had several contingency plans, including the use of poison gas.

On 17 September, 1940, Hitler held a meeting with Reichsmarschall Hermann Göring and Field Marshal Gerd von Rundstedt. Hitler became convinced that the operation wasn't viable. Control of the skies was unavailable, and coordination among three branches of the armed forces was out of question. Later that day, Hitler ordered the postponement of the operation.

It was only a postponement at that stage. Prototypes of two designs of a prefabricated jetty, similar in function to Mulberry Harbours, were built and successfully overwintered in the North Sea in 1941/42. After cancellation, they were installed on the Island of Alderney, where they remained until being demolished in 1978.

Not until 13 February, 1942, after the invasion of Russia, were forces earmarked for the operation released to other duties.
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Old 05-26-2009, 06:27 AM
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Interesting. Some say he could have won the war if he attempted to gain sea superiority. He trearted the navy as a poor stepchild except for the U boats. Even then if he would have put more U boats in the water it, too could have made a difference. He thought he could win the war with Armor & Air with a few battleships thrown in. Just think what would have happened to Britain if he had sea superiority & a couple of aircraft carriers in the Channel or maybe the North Sea even or Atlantic Ocean. Think of the disruption of war supplies, food, medicine, etc. coming from North America. The U boats almost did it by themselves.
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