The Ścibor-Rylski ŚR-3 was a

Polish Polish may refer to: * Anything from or related to Poland, a country in Europe * Polish language * Polish people, people from Poland or of Polish descent * Polish chicken * Polish brothers (Mark Polish and Michael Polish, born 1970), American twin ...

, ultralight, low power, single-seat sports aircraft. First flown in August 1939, only one was completed before

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

Design and development

Like several other amateur Polish designers in the 1930s, Adam Ścibor-Rylski was interested in simple, low cost machines. As a student at the

Warsaw Technical University The Warsaw University of Technology () is one of the leading institutes of technology in Poland and one of the largest in Central Europe. It employs 2,453 teaching faculty, with 357 professors (including 145 titular professors). The student body ...

, he began his studies with the ŚR-1, an attempt to motorize the Wrona basic, open-frame glider. Difficulties in mounting an engine in this structure led to the ŚR-2 which had the Wrona wing married to a new nacelle. By 1937 he had dropped these projects in favour of a more refined, cabin aircraft. This, the ŚR-3, was the subject of his diploma. With the encouragement of

LOPP Air and Chemical Defense League (Polish: ''Liga Obrony Powietrznej i Przeciwgazowej'', ''L.O.P.P.'') was a mass Polish paramilitary organization, founded in 1928 as a result of the merger of the ''State Air Defense League'' (Polish: ''Liga Obrony ...

and the Silesian Gliding Workshop (SWS) he received government funding. The ŚR-3 was a wooden aircraft with a

high High may refer to: Science and technology * Height * High (atmospheric), a high-pressure area * High (computability), a quality of a Turing degree, in computability theory * High (tectonics), in geology an area where relative tectonic uplift t ...

cantilever A cantilever is a rigid structural element that extends horizontally and is unsupported at one end. Typically it extends from a flat vertical surface such as a wall, to which it must be firmly attached. Like other structural elements, a cantilev ...

wing. The wing was a one piece structure built around a single spar and tapered in plan. It was

plywood Plywood is a composite material manufactured from thin layers, or "plies", of wood veneer that have been stacked and glued together. It is an engineered wood from the family of manufactured boards, which include plywood, medium-density fibreboa ...

covered apart from a small fabric covered area aft of the auxiliary spar that carried the

ailerons An aileron (French for "little wing" or "fin") is a hinged flight control surface usually forming part of the trailing edge of each wing of a fixed-wing aircraft. Ailerons are used in pairs to control the aircraft in roll (or movement around ...

. These were unbalanced and operated differentially. It was first fitted with a Avia 4

flat-four engine A flat-four engine, also known as a horizontally opposed-four engine or boxer engine, is a four-cylinder piston engine with two banks of cylinders lying on opposite sides of a common crankshaft. The most common type of flat-four engine is the box ...

which failed during ground trials and was replaced by a Sarolea Albatros

flat twin A flat-twin engine is a two-cylinder internal combustion engine with the cylinders on opposite sides of the crankshaft. The most common type of flat-twin engine is the boxer-twin engine, where both pistons move inwards and outwards at the same ti ...

with a fuel tank in the wing. Behind the engine the fuselage was a rectangular section, stressed ply skinned structure, with a rounded roof between the wing

trailing edge The trailing edge of an aerodynamic surface such as a wing is its rear edge, where the airflow separated by the leading edge meets.Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 521. Aviation Supplies & Academics, 1997. ...

and the tail where the fuselage narrowed strongly in profile. The ŚR-3's single-seat

cockpit A cockpit or flight deck is the area, on the front part of an aircraft, spacecraft, or submersible, from which a pilot controls the vehicle. The cockpit of an aircraft contains flight instruments on an instrument panel, and the controls th ...

was under the wing

leading edge The leading edge is the part of the wing that first contacts the air;Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 305. Aviation Supplies & Academics, 1997. alternatively it is the foremost edge of an airfoil sectio ...

and had an upward hinged, one-piece transparent cover. Its

empennage The empennage ( or ), also known as the tail or tail assembly, is a structure at the rear of an aircraft that provides stability during flight, in a way similar to the feathers on an arrow.Crane, Dale: ''Dictionary of Aeronautical Terms, third ed ...

was also ply covered and unbalanced, with the

tailplane A tailplane, also known as a horizontal stabilizer, is a small lift (force), lifting surface located on the tail (empennage) behind the main lifting surfaces of a fixed-wing aircraft as well as other non-fixed-wing aircraft such as helicopters ...

mounted on top of the fuselage. The

fin A fin is a thin component or appendage attached to a larger body or structure. Fins typically function as foils that produce lift or thrust, or provide the ability to steer or stabilize motion while traveling in water, air, or other fluids. F ...

was almost triangular and carried a full, semi-elliptical

rudder A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, airship, or other vehicle that moves through a fluid medium (usually air or water). On an airplane, the rudder is used primarily to counter adverse yaw ...

which operated between the

elevators An elevator (American English) or lift (English in the Commonwealth of Nations, Commonwealth English) is a machine that vertically transports people or freight between levels. They are typically powered by electric motors that drive tracti ...

. The ŚR-3 had small mainwheels mounted close to the fuselage on short, curved V-struts which had a rubber-in-compression shock absorber within the fuselage. Zbiniew Żabski flew the ŚR-3 on its first flight at the end of August 1939. Though SWS had hoped to produce the ŚR-3 in both kit and complete forms, the

German invasion of Poland The invasion of Poland, also known as the September Campaign, Polish Campaign, and Polish Defensive War of 1939 (1 September – 6 October 1939), was a joint attack on the Second Polish Republic, Republic of Poland by Nazi Germany, the Slovak R ...

a few days after the first flight ended such hopes. The ŚR-3 was reportedly taken by the invaders and flown by the

Dortmund Dortmund (; ; ) is the third-largest city in North Rhine-Westphalia, after Cologne and Düsseldorf, and the List of cities in Germany by population, ninth-largest city in Germany. With a population of 614,495 inhabitants, it is the largest city ...

Nazi Nazism (), formally named National Socialism (NS; , ), is the far-right politics, far-right Totalitarianism, totalitarian socio-political ideology and practices associated with Adolf Hitler and the Nazi Party (NSDAP) in Germany. During H ...

youth organisation.

Specifications

References

{{reflist, refs= {{cite book, title= Polish Aircraft 1893-1939, last= Cynk, first= Jerzy, year= 1971, publisher= Putnam Publishing, location= London, isbn= 0 370 00085 4, page
663-4
url-access= registration, url= https://archive.org/details/polishaircraft1800cynk/page/663 1930s Polish sport aircraft Single-engined tractor aircraft High-wing aircraft Aircraft with conventional landing gear Aircraft first flown in 1939