12. The Germans tried to improve their navigation and bombing precision
With the majority of the bombing missions restricted to night raids to reduce aircraft losses, the Germans relied on radio navigation systems to find their industrial targets. Radio beams transmitted from positions on the continent were aimed to converge over the desired target. German bombers flying along either beam would monitor for the other, and when it picked up the transmission they knew they were over the target and released their bombs. The system worked even in periods of low visibility over the target. The German name for the system was Knickebein, which meant “crooked leg”. Other, more complex systems were developed for the use of the leading pathfinder aircraft, and the British soon developed countermeasures, leading to a phase of the battle known as the Battle of the Beams.
Some beam sources were in the United Kingdom itself, operated by German agents. The British conducted an extensive search, eventually locating the beams and developing the means to jam them. Another countermeasure was the method of modifying the width of the beam, causing the Germans to have difficulty maintaining the strength of signal needed to remain on course to the target. After November 1940, when the heaviest bombing raids of the Blitz were launched, the majority of Luftwaffe bomber pilots no longer had any confidence in the beams and chose to navigate by the tried and true methods of dead reckoning and landmark recognition. The British success in thwarting the German navigation aids contributed to the German technique of adopting area bombing over precision bombing.
