The Zlin Z-26 Trener was a tandem-seat basic training aircraft built by the Czechoslovakian company Moravan. A low-wing monoplane of largely wooden construction, it was developed into a series of all-metal trainers. Several were also produced in aerobatic variants, known as the Akrobat.
The Henschel Hs 130 was a German high-altitude reconnaissance and bomber aircraft developed in World War II. It suffered from various mechanical faults and was never used operationally, only existing as prototype airframes.
The Boeing B-1 was a small biplane flying boat designed by William Boeing shortly after World War I.
The Bleriot-SPAD S.33 was a small French airliner developed soon after World War I. The aircraft was a biplane of conventional configuration whose design owed much to the Blériot company's contemporary fighter designs such as the S.20. Four passengers could be accommodated in an enclosed cabin within the monocoque fuselage, and a fifth passenger could ride in the open cockpit beside the pilot. A great success, the S.33 dominated its field throughout the 1920s, initially on CMA's Paris-London route, and later on continental routes serviced by Franco-Roumaine.
The Breda A.4 was a biplane trainer produced in Italy in the mid-1920s. It was of conventional configuration with a two-bay unstaggered wing cellule and seating for the pilot and instructor in tandem open cockpits. Apart from civil use, the A.4 was also adopted by the Regia Aeronautica as a trainer. At least some examples were produced in floatplane configuration as the A.4idro.
The Caspar C 32 was an aircraft developed in Germany for aerial spraying in the late 1920s. It was a single-bay biplane with staggered, equal-span wings that accommodated the pilot and a single passenger or observer in tandem open cockpits. A small, additional horizontal stabiliser was fitted near the top of the tall single tail fin above the main horizontal stabiliser.
The Hirtenberg HS.9 was an Austrian two-seat touring or training aircraft of the early 1930s.
The Focke-Wulf A 20 Habicht was an airliner developed in Germany in the late 1920s. It was a high-wing cantilever monoplane with fixed tailskid undercarriage. The fuselage was deep and seated four passengers in a fully enclosed cabin. The type was not bought by the airlines and only a few examples were built.
The Focke-Wulf Fw 43 Falke - known internally to Focke-Wulf as the A 43 - was a light utility aircraft developed in Germany in 1932. The last project undertaken by the company under the technical direction of Henrich Focke, it was a high-wing strut-braced monoplane of conventional design, with fixed tailwheel undercarriage. The pilot and two passengers sat in a fully enclosed cabin. Only a single example was built.
The Lohner L was a reconnaissance flying boat produced in Austria-Hungary during World War I. It was a two-bay biplane of typical configuration for the flying boats of the day, with its pusher engine mounted on struts in the interplane gap. The pilot and observer sat side by side in an open cockpit, and both the upper and lower sets of wings featured sweepback.
The Hopfner HV-3/27 was a small airliner built in Austria in the late 1920s. A development of the HV-2, it was a conventional, high-wing cantilever monoplane with a fully enclosed cabin and a strong resemblance to the contemporary Fokker F.II. A single example was built in 1927 and used by Hopfner's own airline until 1934.
The Hopfner HV-4/28 was a small airliner built in Austria in the late 1920s. An enlarged version of the HV-3/27, it was a conventional, high-wing cantilever monoplane with a fully enclosed cabin. A single example was built in 1928 and saw heavy use by the airline that year. In 1929, it received a major refurbishment that included a change or powerplant from the original Heiro to a Gnome et Rhône 9A Jupiter engine and was sold to a private owner under the new designation HV-8/29GR. This aircraft was still flying at the time of the Anschluß, after which it received a new German registration.
The Hopfner HS-5/28 was a utility aircraft built in Austria in the late 1920s. It was a conventional, parasol-wing monoplane with seating for two occupants in tandem, open cockpits. The landing gear was of fixed, tailskid type with divided main units. Two examples were built with Walter NZ60 engines, followed by two more with the more powerful NZ85 for Swiss aeroclub use. One of these latter machines remained in service until 1934.
The Hopfner HS-8/29 was a utility aircraft built in Austria in the late 1920s based on the Hopfner HS-5/28. It used a modernised version of its predecessor's airframe, being a conventional, parasol-wing monoplane with seating for two occupants in tandem, open cockpits. The landing gear was of fixed, tailskid type with divided main units. The first prototype used the same Walter NZ 85 engine that the later HS-5/28s had used, but this was followed by 14 production examples with Siemens engines, and a single prototype with a de Havilland Gipsy III.
The Hopfner HV-6/28 was a small airliner built in Austria in the late 1920s for Swiss use. Unrelated to Hopfner's other airliners of the period, the HV-6/28 was a conventional, high-wing, strut-braced monoplane with a fully enclosed cabin. The main units of the fixed tailskid undercarriage were divided. The single example built was flown by Aero St. Gallen between 1929 and 1931, and then scrapped.
The Hopfner HA-11/33 was an amphibious flying boat built in Austria in 1933 to a specification by the Dr. Oetker company. The result was a conventional, high-wing cantilever monoplane with a stepped flying boat hull and pontoons on struts under the wings at mid-span. The cabin was fully enclosed, and the twin engines were mounted tractor-fashion on struts above the wing.
The Potez 32 and its military version the Potez 33 was a single-engine French monoplane transport built by Potez and based on the Potez 29 biplane.
The Keystone K-55 Pronto was a mail plane developed in the United States in the late 1920s.
The Henschel Hs 121 was the first aircraft built by the German Henschel company. It was a high-wing monoplane with an inline engine, fixed undercarriage and single, open cockpit, designed as an advanced trainer. Only one aircraft was produced, in 1933–4, as a testpiece for the Air Ministry.
The SABCA S.2 was an airliner built in Belgium in 1926.
