The best known German strategic bombing campaign during World War I was the campaign against Britain, although strategic bombing raids were carried out or attempted on other fronts. The main campaign against Britain started in January 1915 using airships. From then until the end of World War I the German Navy and Army Luftstreitkräfte mounted over 50 bombing raids on the United Kingdom. These were generally referred to as "Zeppelin raids": although both Zeppelin and Schütte-Lanz airships were used, the Zeppelin company was much better known and was responsible for producing the majority of the airships used. Weather conditions and night flying conditions made airship navigation and maintaining bombing accuracy difficult. Bombs were often dropped miles off target (one raid on London actually bombed Hull) and accurate targeting of military installations was impossible. The civilian casualties made the Zeppelins an object of hatred, and they were dubbed "baby-killers". With the development of effective defensive measures the airship raids became increasingly hazardous, and in 1917 the airships were largely replaced by aeroplanes.