 Austria-Hungary's U-boat fleet was largely obsolete at the outbreak of World War I.The Austro-Hungarian Navy satisfied its most urgent needs by purchasing five Type UB I submarines that comprised the from Germany, by raising and recommissioning the sunken French submarine "Curie" as , and by building four submarines of the that were based on the 1911 Danish "Havmanden" class.After these steps alleviated the most urgent needs, the Austro-Hungarian Navy had adopted the German Type UB II design for what became known as the Austro-Hungarian "U-27" class in mid 1915, and had six of that class being built under license in Austria-Hungary by late 1916.