 11 was the main aircraft of the Royal Norwegian Navy Air Service up until the German invasion of Norway in 1940.As the final Hansa Brandenburg W.33 seaplane left the Marinens Flyvebaatfabrikk in Horten in 1929 it was already clear that a new machine was needed to fulfil the needs of the RNoNAS.Thus, by the summer of 1929 Marinens Flyvebaatfabrikk and its chief designer, Captain J.E.