The Kammhuber Line was the name given to the German night air defense system established in July 1940 by Colonel Josef Kammhuber. American troops man an anti-aircraft gun near the Algerian coastline in 1943 Anti-aircraft warfare, or air defense, is any method of combating military aircraft from the ground. ... 1940 was a leap year starting on Monday (link will take you to calendar). ... Josef Kammhuber (August 19, 1896 - January 1, 1986) was the first General of the Night Fighters in the Luftwaffe during World War II. He is credited with setting up the first truly successful night fighter defense system, the so-called Kammhuber Line, but a detailed knowledge of the system provided...

The first version of the Line consisted of a series of radar stations with overlapping coverage, layered three deep from Denmark to the middle of France, each covering a zone about 32km long (north-south) and 20km wide (east-west). Each control center was known as a Himmelbett zone, consisting of a Freya radar with a range of about 100km, a "master searchlight" directed by the radar, and a number of manually directed searchlights spread through the cell. Each cell was also assigned one primary and one backup night fighter. The fighter used was usually a Dornier Do 17, Junkers Ju 88 or Messerschmitt Me 110. The Dornier Do 17, sometimes referred to as the Bleistift (pencil) by its pilots, was a World War II light bomber produced by Dornier that was used for a short time by the Luftwaffe. ... The Junkers Ju 88 was a WW2 Luftwaffe twin-engine multi-role aircraft. ... The Messerschmitt Bf110 (later Me110) was a twin-engine heavy fighter in the service of the Luftwaffe during World War II. History Based around the concept of the long-range Zerstörer or Destroyer Fighter the Bf110 enjoyed some success in the Polish and French campaigns. ...

RAF bombers flying into Germany or France would have to cross the line at some point, and the Freya radar operators would direct the master searchlight to illuminate the plane. Once this had happened other manually-controlled searchlights would also pick up the plane, and the night fighter would be directed to intercept of the now-lit bomber. However, demands by the Bürgermeisters in Germany led to the recall of the searchlights to the major cities.

Later versions of the Himmelbett added two Würzburg radars, with a range of about 30km. Unlike the early-warning Freya, Würzburg's were accurate (and complex) tracking radars. One would be locked onto the night fighter as soon as it entered the cell. After the Freya picked up a target the second Würzburg would lock onto it, thereby allowing controllers in the Himmelbett center to get continual readings on the positions of both planes, controlling them to a visual incerception. To aid in this, a number of the night fighers were fitted with a short-range infrared device known as Spanner, but these proved almost useless in practice. Later additions added the short-range Lichenstien radar to the aircraft, allowing them to detect the aircraft once the operators had directed them into the general area. Image of a small dog taken in mid-infrared (thermal) light (false color) Infrared (IR) radiation is electromagnetic radiation of a wavelength longer than visible light, but shorter than microwave radiation. ...

British intelligence soon discovered the nature of the Kammhuber Line and started studying ways to defeat it. At the time Bomber Command sent in their planes one at a time in order to force the defenses to be spread as far apart as possible, meaning that any one aircraft would have to deal with little concentrated flak. However this also meant the Himmelbett centers were only dealing with perhaps one or two planes at a time, making their job much easier. At the urging of R.V. Jones, Bomber Command reorganized their attacks against a single target at a time, sending all of the bombers in a single "stream", carefully positioned to fly right down the middle of a cell. Now the Himmelbett centers were facing hundreds of bombers, countering with only a few planes of their own. This tactic was extremely effective, leading to fighting between Kammhuber and Erhard Milch, his boss. Bomber Command is an organizational military unit, generally subordinate to the air force of a country. ... Professor R V Jones Reginald Victor Jones (28 September 1911–17 December 1997) was an English physicist and scientific military intelligence expert. ... Air Marshall Erhard Milch Erhard Milch (March 30, 1892 – January 25, 1972) was an official of the Nazi government who oversaw the development of the Luftwaffe as part of the re-armament of Germany following World War I. Milch was born in Wilhelmshaven. ...

Although the success rate dropped, the network of radars and plotting stations continued to prove their worth. Now when a raid started, night fighters from any base within range would be directed into the stream, where it was hoped they would be able to find aircraft with their own radars. At the same time a massive building program started to add hundreds of additional Würzburg's to the system, although the infrastructure needed was extensive. The boxes were intially the radius of the Würzburg radars, about 22 miles, but more powerful radar later on made the boxes up to 100 miles across. Eventually, the line of boxes would be several deep, especially around larger towns and the Ruhr valley. Once again the system started to score increasing successes against the British raids. Geography Map of the Ruhr Area The Ruhr Area (German Ruhrgebiet or, colloquially, Ruhrpott) is a metropolitan area in North Rhine-Westphalia, Germany, consisting of a number of large industrial cities bordered by the rivers Ruhr to the south, Rhine to the west, and Lippe to the north. ...

The British were ready for this development, however, and as soon as the rates started to improve they added 'windowing' cover. By dropping chaff from a number of "lead" bombers, the German radar operators saw what appeared to be a stream entering their box. The first time this was used was during the firestorm attack on Hamburg, (Operation Gomorrah), and proved spectacularly effective. The Germans radar operators eventually learned to spot the lead bombers at the edge of the windowing, making it less effective. Window was the WWII UK codename for a system called chaff, intended to confuse German radar. ... Chaff is the seed casings and other inedible plant matter harvested with cereal grains such as wheat. ... This is an article about a specific circumstance of combustion. ... Position of Hamburg in Germany Hamburgs central broadway Jungfernstieg at the Alster lake, between 1900 and 1914 This article is about the city in Germany. ... Firestorm in Hamburg Operation Gomorrah was the military codename for a series of air raids conducted by the Royal Air Force on the city of Hamburg beginning in the end of July 1943. ...