He 115V-1
Prototype V1 had its inaugural flight in August of 1937. This conventional stressed-skin aircraft was entirely made of metal and boasted a slender fuselage, a mid-mounted wing featuring a rectangular centre-section and sharply tapered outer panels, a braced tailplane, and twin BMW 132K engines (derived from the Pratt & Whitney Hornet), each producing 715 kW (960 hp). It had single-step floats, attached by tandem struts and multiple bracing wires. The wings included simple slotted flaps, the tailplane was fixed, and large trim tabs were incorporated into all control surfaces. The fuselage was designed to accommodate a crew of three, with the pilot’s cockpit located above the wing leading edge and covered by a sliding canopy. The glazed nose included a seat for the observer, who was also equipped with a bombsight, as well as an MG 15 machine-gun in an upper cupola. Above the trailing edge, the radio operator’s cockpit was situated, who was also equipped with an MG 15 for upper rear defence. The area beneath the wing’s fuselage was fashioned as an internal weapons bay, capable of carrying an 800-kg (1,763-lb) torpedo or three SC 250 1,250-kg (550-lb) bombs.
Overall, the He 115 was an incredibly sturdy aircraft that handled well and displayed no significant shortcomings. In March of 1938, the prototype was modified with streamlined fairings over the nose and dorsal cockpits and provided with greater fuel capacity, by which time the 115 had been selected for the Luftwaffe Seeflieger. The aircraft was used to establish world records for speed with a load, covering closed circuits of up to 2,000 km (1,242 miles) with payloads of up to 2,000 kg (4,410 lb) at an average speed of 328 km/h (203 mph).