The Lublin R-XX was the

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 ...

torpedo bomber A torpedo bomber is a military aircraft designed primarily to attack ships with aerial torpedoes. Torpedo bombers came into existence just before the World War I, First World War almost as soon as aircraft were built that were capable of carryin ...

floatplane A floatplane is a type of seaplane with one or more slender floats mounted under the fuselage to provide buoyancy. By contrast, a flying boat uses its fuselage for buoyancy. Either type of seaplane may also have landing gear suitable for land, ...

, designed in the early 1930s in the

Plage i Laśkiewicz Plage i Laśkiewicz (Plage & Laśkiewicz) was the first Polish aerospace manufacturer, located in Lublin and manufacturing aircraft under Lublin name. Full name was: ''Zakłady Mechaniczne E. Plage i T. Laśkiewicz'' – Mechanical Works E. Plag ...

factory in

Lublin Lublin is List of cities and towns in Poland, the ninth-largest city in Poland and the second-largest city of historical Lesser Poland. It is the capital and the centre of Lublin Voivodeship with a population of 336,339 (December 2021). Lublin i ...

. It remained a prototype.

Design and development

In 1930 the Polish Ministry of Defence announced a contest for a torpedo-bomber floatplane for the

Polish Navy The Polish Navy (; often abbreviated to ) is the Navy, naval military branch , branch of the Polish Armed Forces. The Polish Navy consists of 46 ships and about 12,000 commissioned and enlisted personnel. The traditional ship prefix in the Polish ...

. Plage i Laśkiewicz works proposed first a floatplane variant F.VIIW of a licence-built bomber (developed from a passenger plane) Fokker F.VII, but it was not built. It also proposed a floatplane variant of single-engined Lublin R-VIII biplane bomber. In a course, three R-VIIIs were converted to floatplanes and given to the Navy, but they did not meet all demands, for they were obsolete, slow and could not carry

torpedo A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, such ...

es. Then Plage i Laśkiewicz proposed quite modern twin-engined plane Lublin R-XX, the main designer of which was

Jerzy Rudlicki Jerzy Rudlicki (Polish pronunciation: ; 14 March 1893 – 18 August 1977) was a Polish pilot and aerospace engineer. Best known for his inventing and patenting of the V-tail, which is an aircraft tail configuration that combines the rudder and e ...

. The last design won the contest in 1932, besting PZL-18 and PWS-62 designs, and a prototype was ordered. It was initially planned to build a series of 9. In 1934 the prototype was built and on 22 June transported to Puck - a base of the Naval Aviation Squadron (''MDLot''). It appeared there, that it was tail-heavy on water, and it demanded some modifications, like lengthening engine nacelles towards front. It first flew on 8 April 1935 (some sources: 10 AprilMorgała, Andrzej: ''Samoloty w polskim lotnictwie morskim'', WKiŁ, Warsaw, 1985, ). Initially the plane was kept in secret. The design was found satisfactory, but it had also faults, like moving of centre of gravity during flight and low fuselage rigidity. The prototype was modified then and returned from the factory for further trials on 30 October 1935. In early 1935 an improved variant R-XXA was developed. It had more streamlined fuselage, covered machine gun turrets with 6 machine guns, smaller span of 23.65 m and stronger engines 750 hp

Pegasus Pegasus (; ) is a winged horse in Greek mythology, usually depicted as a white stallion. He was sired by Poseidon, in his role as horse-god, and foaled by the Gorgon Medusa. Pegasus was the brother of Chrysaor, both born from Medusa's blood w ...

III. The Polish Navy ordered 6 production aircraft in the beginning of 1935, with planned deliveries by April 1937, and Plage i Laśkiewicz prepared to build the R-XXA prototype. However, the factory at that time was about to

bankrupt Bankruptcy is a legal process through which people or other entities who cannot repay debts to creditors may seek relief from some or all of their debts. In most jurisdictions, bankruptcy is imposed by a court order, often initiated by the de ...

(caused by a policy of Ministry of Defence, refusing to buy

Lublin R-XIII The Lublin R-XIII was the Polish army cooperation plane (observation and liaison plane), designed in the early-1930s in the Plage i Laśkiewicz factory in Lublin. It was the main army cooperation plane in the Invasion of Poland. Its variant Lu ...

f planes), and on 23 November 1935 the Navy Headquarters broke off an order for R-XXA due to long development. After nationalization of the bankrupt Plage i Laśkiewicz works in 1936, as the LWS, the R-XXA design was taken over as the LWS-1. However, its development was soon canceled in mid-1936, because the factory proposed a floatplane variant LWS-5 of slightly more modern

LWS-6 Żubr The LWS-6 Żubr (PZL.30, ''wisent'') was a twin-engined medium bomber designed and produced by the Polish aircraft manufacturer LWS. It was only produced in limited numbers and was used for training purposes as it proved to be inferior to the cont ...

bomber. This design was not completed as well, and the Polish Navy remained without torpedo bombers (there were finally ordered six CANT Z.506 in Italy, but only one unarmed was delivered by the outbreak of the war). The only R-XX prototype was used in the MDLot with a number 806 until September 1937, when it was written off, then scrapped in 1938. It was planned to use floats for LWS-5 prototype. There was also a preliminary design of a medium bomber R-XXB, from 1934-1935. It was to have a streamlined fuselage and covered gun turrets, similar to R-XXA. Main difference was a fixed conventional

landing gear Landing gear is the undercarriage of an aircraft or spacecraft that is used for taxiing, takeoff or landing. For aircraft, it is generally needed for all three of these. It was also formerly called ''alighting gear'' by some manufacturers, s ...

with wide covers and a single tailfin. It was to carry 600 kg bombs (some sources - 1500 kg). It was less modern, than

(PZL.30) and

PZL.37 Łoś The PZL.37 ''Łoś'' ('moose') was a Polish twin-engined medium bomber designed and manufactured by national aircraft company Państwowe Zakłady Lotnicze (PZL). It is sometimes incorrectly referred to as "PZL P.37", but the letter "P" was reserve ...

and the plane, redesignated later as LWS-1/II, was not built.

Variants

;R-XX :Prototype. ;R-XXA :Improved version with streamlined fuselage, covered machine gun turrets, smaller span and stronger Pegasus III engines. Six were ordered, none built. ;R-XXB :Preliminary design of a medium bomber.

Operators

; *

Description

Mixed construction low-wing cantilever

monoplane A monoplane is a fixed-wing aircraft configuration with a single mainplane, in contrast to a biplane or other types of multiplanes, which have multiple wings. A monoplane has inherently the highest efficiency and lowest drag of any wing con ...

, two-engine, conventional in layout. A fuselage was square in cross-section, made of a steel frame, canvas-covered (duralumin-covered in front). Wings of wooden construction, two-spar, plywood-covered. Twin strutted tail. Crew of five: in a glazed nose a bombardier-gunner, then two pilots, sitting side by side in an open

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 ...

. In mid-fuselage a radio operator and an upper gunner. Two Short metal floats. Four-blade wooden

propeller A propeller (often called a screw if on a ship or an airscrew if on an aircraft) is a device with a rotating hub and radiating blades that are set at a pitch to form a helical spiral which, when rotated, exerts linear thrust upon a working flu ...

s, later three-blade metal ones. Two fuel tanks 1680 L in wings. Armament: four 7.9 mm Vickers F machine guns on ring mountings in fuselage nose and in a dorsal position. According to some sources, also one underbelly machine gun. Bomb load: up to 1,000 kg (other sources - 600 kg) or 750 kg torpedo.

Specifications (R-XXA factory data)

Notes