posed by the submarines of the Imperial German Navy to the merchant ships sailing along the Portuguese coast during World War I, the French government asked Portugal permission to install a naval air station in Portugal. 1st Lieutenant Maurice Larrouy, of the French Navy, elaborated a study which proposed the installation of an airship and hydroplane base in Lisbon, and two additional hydroplane bases in the north and south of Portugal. However, due to the logistics costs of operating airships, Sacadura Cabral opposed the plan of installing an airship base in Lisbon and instead the decision was made to equip Bom Sucesso with anti-submarine flying boats and to build a hydroplane base for the French Naval Aviation in Aveiro. Creation of the Navy's Aviation Service On September 28, 1917, the Navy's Aviation Service () was created with its personnel, material and aviation school being separated from the Army's EAM. The service was then installed at the Bom Sucesso Naval Air Station in the Lisbon docks. Two F.B.A. flying boats, received in March 1917 and stored at EAM, arrived at Bom Sucesso by December 1917, marking the beginning of the Navy's independent flight operations. For the centennial, on September 28, 2017, citizens and tourists near the Torre de Belém in Lisbon were treated to a short afternoon air show of planes and helicopter over the Tagus River plus an anniversary ceremony on the riverbank including a military band. Naval Aeronautics Service On January 5, 1918, the naval aviation was renamed to Naval Aeronautics Service (). In April 1918 the first flying boats of the French Navy arrived at São Jacinto, in Aveiro. Together with the Portuguese aircraft at Bom Sucesso naval air station, this allowed them to perform anti-submarine patrols and cover the coastal Portuguese waters and the main ports. This same year the United States Navy started operating Curtiss HS-2L hydroplanes from Horta, Faial Island. With the end of the war the French Navy left São Jacinto and handed over the naval air station to the Portuguese Navy as well as 18 Donnet-Denhaut D.D.8 and two Georges Levy G.L.40 flying boats as a gift. On December 28, 1918, a Portuguese Navy officer took command of the São Jacinto Naval Air Station (). The United States Navy left as well their base at Horta and offered to the Portuguese Navy four Curtis HS-2L. These aircraft were transported and ship to Lisbon