Josef Kammhuber - World War II

World War II

Kammhuber, realizing what was going on, put in a request in February 1939 for active duty. Promoted to Generalmajor (Major General), he was assigned as chief-of-staff of Luftflotte 2, and was in this position at the start of the war in September. On 11 January 1940, he was cashiered by Hitler personally because of the Mechelen Incident. He was transferred to the Western Front where he became Geschwaderkommodore of KG 51, a tactical bomber unit. During the French campaign he was shot down and captured, and interned in a French POW camp at the age of 44. He was released at the end of the Battle of France in July 1940, and returned to Germany.

Once again an officer of the Luftwaffe's Generalstab, in July 1940 he was placed in command of coordinating flak, searchlight and radar units. At the time they were all under separate command and had no single reporting chain, so much of the experience of the different units was not being shared. The result was the XII. Fliegerkorps, a new dedicated night-fighting command. At this time, Kammhuber was promoted to Generalleutnant (Lieutenant General).

He organized the night fighting units into a chain known to the British as the Kammhuber Line, in which a series of radar stations with overlapping coverage were layer three deep from Denmark to the middle of France, each covering a zone about 32 km long (north-south) and 20 km wide (east-west). Each control center was known as a Himmelbett (4-poster bed) zone, consisting of a Freya radar with a range of about 100 km, a number of searchlights spread through the cell, and one primary and one backup night fighter assigned to the cell. RAF bombers flying into Germany or France would have to cross the line at some point, and the radar would direct a 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

Later versions of the Himmelbett added two Würzburg radars, with a range of about 30 km. Unlike the early-warning Freya radar, Würzburgs 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 interception. To aid in this, a number of the night fighters were fitted with a short-range infrared device known as Spanner, but these proved almost useless in practice.

Another tactic that proved effective was to send their own planes to England while the raids were taking off or landing. Radio operators listening to the RAF bomber frequencies were able to recognize the start of a raid, and the raiding force of about 30 night fighters would be sent over the RAF airbases to shoot down the bombers as they took off or landed. By the beginning of October the night intruder force had claimed a hundred kills but on October 13 Hitler ordered the force sent to the Mediterranean despite their success.

British intelligence soon discovered the nature of the Kammhuber Line and started studying ways to defeat it. At the time RAF 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. So successful was this tactic that the success rate of the night fighters dropped almost to zero.

Kammhuber started looking for solutions, and the result was the two-prong concept of Wilde Sau ("wild boar") and Zahme Sau ("tame boar"). In the former, day fighters would be sent up and look for the bombers from the light of flares dropped from light bombers, searchlights set to a wide beam or illuminating lower clouds, or the fires on the ground below. The Wilde Sau force scored their most notable success during the British operation against the V-weapon centre Peenemünde on 17 August 1943. de Havilland Mosquito bombers had dropped target marker flares over Berlin and most of the night fighter force was sent there. When it was realized what was really happening, most of these aircraft were too far away and too slow to intercept the raid. The Focke-Wulf Fw 190s being flown by the Wilde Sau forces were however able to reach them, and about 30 planes entered the third and last wave of the stream and shot down 29 of the 40 Avro Lancaster bombers lost that raid.

Zahme Sau envisioned freeing the night fighters (now equipped with radar for the final stages of the interception) from the Himmelbett cells and allowing them to attack on their own. This was not all that easy, given the current generation of radars, but newer systems being developed would greatly increase the detection range and angles. In this role the existing cells created as part of the original Kammhuber Line would be used primarily for early warning and vectoring the planes to the stream.

At the same time Kammhuber continued to press for a new dedicated nightfighter design, eventually selecting the Heinkel He 219 Uhu after seeing it demonstrated in 1942. However Milch had decided to cancel the Uhu, and fighting broke out between the two. As a result in 1943 Kammhuber was transferred to Luftflotte 5 in Norway, in command of a handful of outdated planes. After the reorganization of the Luftwaffe in Scandinavia and the dissolution of Luftflotte 5, he became commanding general of the Luftwaffe in Norway (September–October 1944). In 1945 he was re-appointed to command of the night fighters, at this point a largely ceremonial position considering the state of the Third Reich at that time.