Heinkel He 59 biplane floatplanes on exercise during the late 1930s

The Heinkel He 59 was a twin-engined German biplane designed in 1930 to meet a Reichsmarine requirement for a torpedo bomber and reconnaissance aircraft able to operate on wheeled landing gear or twin-floats.

The aircraft was of a mixed-material construction. The wings were made of a two-beam wooden frame, where the front was covered with plywood and the rest of the wing was covered with fabric, while the tail section was covered with sheet metal. The box-shaped fuselage was a fabric-covered steel frame. The keels of the floats were used as fuel tanks with each one holding 900 L The propellers were fixed-pitch with four blades and driven by BMW VI 6.0 zu V-12 liquid-cooled engines.

During the first months of World War II, the He 59 was used as a torpedo- and minelaying aircraft. It was also serving with various Seenotstaffeln (Air Sea Rescue) as well as landing troops in Norway and Holland in the Spring of 1940. Between 1940 and 1941 the aircraft was used by four KüFlGr (Kürstfliegergruppe/Coastal reconnaissance group), and in 1941-42 as a transport, air-sea rescue, and training aircraft. Some had been operated by the Condor Legion in Spain during the Spanish Civil War in 1936 as coastal reconnaissance and torpedo floatplanes.

During the Battle of Britain, they were used to rescue Luftwaffe aircrew who were forced to ditch in the English Channel. In spite of their Red Cross markings in this role, the British claimed that the air-sea rescue aircraft were being used for reconnaissance and were therefore legitimate targets, with several being brought down. A statement from the Air Ministry on July 14th 1940 read as follows:

"Enemy aircraft bearing civil markings and marked with the Red Cross have recently flown over British ships at sea and in the vicinity of the British coast, and they are being employed for purposes which His Majesty’s government cannot regard as being consistent with the privileges generally accorded to the Red Cross.

His Majesty’s government desire to accord the ambulance aircraft reasonable facilities for the transportation of the sick and wounded in accordance with the Red Cross Convention, and aircraft engaged in direct evacuation of the sick and wounded will be respected, provided that they comply with the relevant provisions of the Convention.

His Majesty’s government are unable, however, to grant such immunity to aircraft flying over areas in which operations are in progress on land or at sea, or approaching British or Allied territory, or territory in British occupation, or British or Allied ships. Ambulance aircraft which do not comply with the above requirements will do so at their own risk and peril."

The British were keen to maintain vital shipping routes, particularly through the Channel, and had put one and one together and come up with three. They believed that German air-sea rescue aircraft were spotting British shipping which was subsequently attacked. In fact there is no evidence that this was the case and the interrogations of surviving crew from these aircraft shows that they were genuinely surprised at the suggestion they would do such a thing. The aircraft were unarmed and the crews all registered with the Red Cross in Geneva, but this was not enough to persuade the British.

Most of the 140 B-2s and B-3s built by Arado were later converted by the Walter Bachmann Flugzeugbau for air/sea rescue (He 59C-2 and D-1) or specialized training in navigation (He 59C-1, D-1 and N), torpedo dropping (E-1) and photographic roles (E-2). All these variants were unarmed with the exception of the the He 59N.