Hansa-Brandenburg GW

The Hansa-Brandenburg GW was a floatplane torpedo bomber designed by the Hansa-Brandenburg Aircraft Company () for the Imperial German Navy's () Naval Air Service () during World War I. One prototype was built in 1916 and was followed by twenty production aircraft.

Design and development

After the submarine Template:SMU sank three British armored cruisers on 22 September 1914 shortly after the war began, the German Imperial Naval Office () decided to try mounting torpedoes on aircraft as they were far easier and faster to build than submarines. Early trials with land-based aircraft were unsuccessful because of the great weight of the torpedo () was more than existing aircraft could easily lift and the danger of trying to fly from an uneven grass airstrip with such a large weight of explosives. At the beginning of 1915 the Naval Office ordered the development of seaplanes capable of carrying torpedoes and the Seaplane Experimental Command ( (SVK)) issued requirements for these aircraft. They had to be twin-engine airplanes armed with a machine gun for self-defense and with a crew of two or three men: a pilot and observer for torpedo missions and a pilot, bombardier and gunner for bombing missions.

Ernst Heinkel, chief designer of Hansa-Brandenburg, stated that the GW was based on the twin-engined GF series of bomber designs that led to the land-based G.I bomber, but the GW was substantially larger and heavier. Like the G.I, it was a conventional three-bay biplane design with equal-span wings. The undercarriage consisted of two widely spaced floats to allow for the torpedo to be carried between them. The floats were attached to the fuselage and wings by multiple V-struts. The two Mercedes D.III straight-six engines were positioned between the wings, supported by pairs of V-struts, driving two-bladed propellers.

Improvements were continually made in the GW's design during its time in production. The prototype had a long nose fitted with a cockpit for the unarmed observer, forward of the pilot's cockpit, and it had three rudders at its tail, positioned above the horizontal stabilisers. Its radiators were mounted on the struts above the engines. The first batch of production aircraft received a Parabellum MG14 machine gun on a flexible mount for the observer, the shape of the tailplane was modified and the radiators were embedded in the upper wing. Some of the second batch only had a single balanced rudder that extended above and below the fuselage. All of the aircraft in the third batch had the single rudder and the observer's cockpit was moved behind the pilot while those of the fourth batch received balanced elevators.

Operational history

The first batch of five GWs were delivered to the SVK in January 1916 and they began to be transferred to the torpedo training unit in Kiel-Holtenau, informally known as , the following month. Aircraft from the second batch of five aircraft began arriving at the training unit beginning in April. In June a small squadron () of four GWs was declared operational and ready for deployment to the Eastern Front.