The Hopfner HA-11/33 was an amphibious flying boat built in Austria in 1933 to a specification by the
Dr. Oetker
Dr. Oetker () is a German multinational company that produces baking powder, cake mixes, Pizza#Preparation, frozen pizza, pudding, cake decoration, cornflakes, birthday candles, beer, and various other products.
The company is a wholly owned b ...
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.
Development
A HA-11/33 was purchased by the
Austrian Air Force
The Austrian Air Force () is a component part of the Austrian Armed Forces.
Aircraft
Current inventory
History
The Austrian Air Force in its current form was created in May 1955 by the victorious Allies of World War II, Allied powers ...
, and was subsequently absorbed into the German
Luftwaffe
The Luftwaffe () was the aerial warfare, aerial-warfare branch of the before and during World War II. German Empire, Germany's military air arms during World War I, the of the Imperial German Army, Imperial Army and the of the Imperial Ge ...
following the
Anschluss
The (, or , ), also known as the (, ), was the annexation of the Federal State of Austria into Nazi Germany on 12 March 1938.
The idea of an (a united Austria and Germany that would form a "German Question, Greater Germany") arose after t ...
. Deemed worthy of further development,
WNF (which had absorbed
Hirtenberg
Hirtenberg is a town of approx. 2,500 inhabitants near Baden bei Wien in Lower Austria, Austria. The river Triesting is located at the south border of the town. Coming from the Vienna Woods, the valley of Triesting joins the Vienna Basin here.
Ne ...
, which itself had taken over
Hopfner) was tasked with developing it into a military training aircraft for flying boat pilots. Designated WNF Wn 11 by the
RLM, testing was undertaken at
Travemünde
Travemünde () is a borough of Lübeck, Germany, located at the mouth of the river Trave in Bay of Lübeck, Lübeck Bay. It began life as a fortress built by Henry the Lion, Duke of Saxony, in the 12th century to guard the mouth of the Trave, an ...
in 1940, but the type was not ordered into production. Development of a highly streamlined derivative with
Hirth HM 508
The Hirth HM 508 was an air-cooled, eight-cylinder, 60° cylinder bank angle inverted-V aircraft engine built in Germany in the 1930s. It had a bore and stroke of 105 mm × 115 mm (4.1 in × 4.5 in) and developed 210 kW (280 ...
engines, the WNF Wn 11C was also abandoned.
Specifications
References
Further reading
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External links
Hopfner HA.11/33Уголок неба. 2011
{{DEFAULTSORT:Hopfner HA-11 33
HA-11 33
Wiener Neustadter aircraft
1930s Austrian civil utility aircraft
Flying boats
Amphibious aircraft
High-wing aircraft
Twin piston-engined tractor aircraft
Aircraft first flown in 1933