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Under Water Warfare The Struggle Against the Submarine Menace 1939 -1945
Enigma and aircraft defences

This complicated electro mechanical machine fitted with 3 wheels, and inserted into a steel cylinder was capable or producing 150 Trillion ( million million millions) possible substitutions for each letter in a signal, This machine coined its name from Elgar's "Enigma Variations." It did not have to be kept a secret, just the way it was set each day maintained the sanctity of its messages.

As early as February 1940, the most aptly named Mine Sweeper "Gleaner," sank U33 minelaying in the Clyde, and three "Enigma" wheels were found during a search made on survivors. The British were able to read German Naval messages to and from U-Boats until February 1942, when a new cipher called "Triton," was introduced. For this cipher, a 4th. wheel was added to the "Enigma," machine, making it 26 times more difficult to crack open messages.

Bletchley Park took 10.5 months to break into "Triton."

It would seem that the main benefit of reading German U-Boat signals was the facility to divert Convoys away from potential danger areas. Donitz had no idea his U-Boat signals had been compromised, and reports stated he was shattered to learn this fact in his old age.


(a) German
In essence,German reconnaissance Aircraft working in conjunction with U-Boats were operating offensively. The Focke-WuIf Kondor (sometimes spelled Condor.) was a four engined long range reconnaissance Aircraft used to roam the gap in the Atlantic to locate Convoys, and then home U-Boats onto the scene.

With the fall of France, the Luftwaffe, was able to make use of the French air base near Bordeaux.

In Autumn 1940, a second FW, base was opened at Sravanger in Norway, allowing these Aircraft to now fly 2,000 miles. As well as carrying out reconnaissance, the Kondor attacked Merchant Ships, and in their first full month of operation they actually sank 15 ships totalling 53,000 tons. In January 1941 Hitler placed Group 40, FW Aircraft under Donitz's command. It was done whilst Goring was away on a hunting holiday. On his return, Goring fought this decision, and got the group back. but a Former Naval Officer, LieutenantColonel Martin Harlughausen became the group's Commander, and Donitz had to be satisified.

To close the air gap in mid Atlantic, where effective air cover against the FW could not be given, the CAM Ship, and Auxiliary Carrier were spawned.

(b) British
Post W W I, and pre W W 2 the RAF set up a Coastal Area Command to cooperate with, but not to serve under the Royal Navy.

In 1937, the British Cabinet decided the Navy would take over the Fleet Air Arm, and the R.A.F. retain Coastal Command. It is of interest to note, that at this stage, the U.S. Navy had 2,000 Aircraft in service, but the Royal Navy could but muster 400. At the declaration of war on the 3rd, of September, 1939, the R.A.F. Coastal Command had, on paper, 17 Squadrons, but in fact, was poorly equipped with "Ansons," having limited fuel capaciry, and Bomber Command obtained priority over its Cinderella sister Coastal Command.

By early 1941, both Hudson Bombers, and Sunderland Flying Boats were stationed in Iceland. It was Coastal Command Aircraft that found "Bismarck," and "Prinz Eugen," in a fjord south of Bergen in late May 1941, after the British Naval Attache in Stockholm had earlier reported they were on the move.

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