The Heinkel He 119 was an experimental single-propeller monoplane with two coupled engines, developed in Germany. A private venture by Heinkel to test radical ideas by the Günter brothers, the He 119 was originally intended to act as an unarmed reconnaissance bomber capable of eluding all fighters due to its high performance.
The Fokker C.XI-W was a reconnaissance seaplane designed to operate from warships that was produced in the Netherlands in the mid-1930s. It was the result of a Royal Netherlands Navy specification of 1935 requesting such an aircraft. Fokker's response was a conventional single-bay biplane with staggered wings of unequal span braced by N-struts. The pilot and observer sat in tandem, open cockpits, and the undercarriage consisted of twin pontoons. The wings were of wooden construction with plywood and fabric covering, and the fuselage was of steel tube, also covered with fabric.
The Heinkel HD 24 was a training seaplane developed in Germany in the late 1920s. It was a conventional single-bay biplane with equal-span, staggered wings. The fuselage was braced to both the upper and lower wings with a number of struts on its sides, in addition to the normal cabane struts. The pilot and instructor sat in tandem, open cockpits, and the undercarriage consisted of twin pontoons, although this could be readily exchanged for wheels or skis.
The Heinkel HD 25 was a two-seat shipboard biplane reconnaissance floatplane developed in Germany during the 1920s for production in Japan.
The Heinkel HD 26 was a reconnaissance seaplane developed in Germany during the 1920s for production in Japan. It was intended as a smaller, single-seat counterpart to the HD 25, to provide a spotter aircraft for warships, to take off from a short ramp. The HD 26 was a conventional biplane with staggered wings, twin float undercarriage, and an open cockpit.
The Heinkel HD 55 was a biplane flying boat produced in Germany in the early 1930s for use as a reconnaissance aircraft aboard Soviet warships. The design was based on the HD 15 mail plane of 1927 and was a conventional design for its time, with equal span, unstaggered wings, and an engine mounted tractor-wise on struts above the pilot's open cockpit. A second open cockpit was added on the rear fuselage to provide a position for a tail gunner.
The Aichi E3A was a reconnaissance seaplane developed in Germany as the Heinkel HD 56 to operate from warships of the Imperial Japanese Navy, which designated it the Type 90-1 Reconnaissance Seaplane. It was a conventional single-bay biplane with staggered wings braced by N-type interplane struts. The pilot and gunner sat in tandem, open cockpits.
The Aichi AB-1 was a result of a 1926 government call for a small, Japanese-built, civil transport biplane able to operate from land or water. It won the contest in both roles but did not reach production as airlines moved from biplanes to monoplanes. Nonetheless, it remained in commercial use well into the 1930s.
The Heinkel He 62 was a reconnaissance seaplane designed in Germany in the early 1930s. It was a conventional, single-bay biplane with unstaggered wings of equal span. The pilot and gunner sat in tandem, open cockpits. A few aircraft were supplied to Japan, where Aichi built a version as the AB-5, and used it as the basis for the AB-6, but no series production took place. The AB-5 used a locally produced Nakajima Kotobuki in place of the Siemens engine fitted to the German-built aircraft.
The Henschel Hs 122 was a German army cooperation/reconnaissance aircraft of the mid-1930s, radial-engined and with a parasol wing. Though only pre-production variants entered service, the Hs 122 led on to the Hs 126 which was produced in large numbers.
The Kawanishi E11K was a Japanese flying boat of the 1930s. It was designed as a night reconnaissance aircraft for the Imperial Japanese Navy, but was not accepted, the two aircraft built being used as transports as the Type 96 Transport Flying Boat during the Second World War.
The Nakajima P-1 was a 1930s Japanese single engine, single seat biplane intended for night mail flights, derived from the Nakajima E4N3 Naval reconnaissance seaplane. Nine were built.
The Aichi AB-6, or Aichi Experimental 7-Shi Reconnaissance Seaplane, was a prototype Japanese reconnaissance floatplane. It was a single-engined, three-seat biplane intended for the Imperial Japanese Navy, but only one was built, the rival aircraft from Kawanishi, the E7K being preferred.
The Aichi F1A was a prototype Japanese floatplane of the 1930s. A single-engined biplane, the F1A was intended as a short-range observation aircraft suitable for operation off the Imperial Japanese navy's warships, but only two were built, the Mitsubishi F1M being selected instead.
The Aichi AB-2 was a prototype Japanese reconnaissance floatplane of the 1930s. It was a single-engined biplane, of which two examples were built, but no production followed.
The Blackburn G.P seaplane,, was a British twin-engine reconnaissance torpedo floatplane of the First World War, built by the Blackburn Aeroplane and Motor Co Ltd.
The Kawanishi E10K, also known as Kawanishi Type T, Kawanishi Navy Type 94 Transport Seaplane and Kawanishi Navy Experimental 9-Shi Night Reconnaissance Seaplane, was a small Japanese flying boat of the 1930s. It was a single-engined biplane intended to meet a requirement for a night reconnaissance aircraft for the Imperial Japanese Navy, but was not selected for production, the single prototype being converted to a transport and operated as the Navy Type 94 Transport.
The NVI F.K.34 was a three-seat reconnaissance seaplane built in the Netherlands in 1925 as a private venture in the hope of a Dutch Naval Aviation Service order; two accidents during testing meant that it did not go into production.
The Heinkel HD 20 was a twin engine, three seat German biplane built in 1926 for civil survey work.
The Kawanishi E13K, company designation AM-19, was a Japanese 1930s three-seat reconnaissance floatplane.
