 The Battle of the Heligoland Bight was the first "named" air battle of the Second World War, which began the longest air campaign of the war, the Defence of the Reich. On 3 September 1939, the United Kingdom declared war on Nazi Germany after the German invasion of Poland, which started the European War. The British did not assist Poland by land or sea, but over the ensuing weeks, RAF Bomber Command flew several missions against German targets. A number of these air raids were directed at Kriegsmarine (German Navy) warships in German ports to prevent their use in the Battle of the Atlantic. With the front lines static between September 1939 and May 1940, a period known as the "Phoney War" set in, with little fighting on land or in the air. However, at sea, German U-boat (submarine) forces were taking a considerable toll on Allied shipping. The Air Ministry decided to launch an attack on German surface ships to prevent them supporting the U-boats in the North Atlantic. On 18 December 1939, a force of three RAF bomber squadrons were sent to engage German ships in the Heligoland Bight and sink or damage as many as possible. Originally 24 Vickers Wellingtons took off. Two turned back owing to engine trouble before reaching German airspace. The German reaction was slow. Eventually they scrambled strong fighter aircraft forces to intercept. Just over 120 aircraft, 80 – 100 German and 22 British, were involved but only 44 German fighters made contact with the British bombers.
