The Lublin R-XIII was the Poland army cooperation plane (observation and liaison aircraft 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 Lublin R-XIV was a military trainer aircraft.
The contest was won by the R-Xa, having the shortest take-off and landing, and good performance, but the factory was ordered to develop design further. At that time, Rudlicki was working upon an unarmed trainer aircraft R-XIV and an observation aircraft R-XV. Both were new designs, basing upon the R-X construction. Number XIII was initially omitted in designations as "unlucky". In February 1930, the Polish Air Force ordered 15 of R-XIV. The first serial plane was built in June 1930, without an earlier prototype, and all were delivered by July 1931. The R-XIV was a two-seater, parasol wing aircraft, with a 220 hp radial engine and fixed landing gear. The crewman sat in open cabs in tandem. The R-XV was not ordered, but the Air Force demanded instead, that two R-XIV should be armed with an observer's machine gun, for testing. Thus armed, the R-XIV, fitted also with other minor modifications, most notably a changed shape of a tail fin, became the first prototype of the army-cooperation plane, that eventually received a designation Lublin R-XIII. One more prototype was newly built (no. 56.1).Morgała, Andrzej (2003), p. 191-192
On July 21, 1931, 50 aircraft R-XIII were ordered. The first couple of aircraft were designated R-XIIIA, and were distinguished by flat fuselage top. They were superseded by improved R-XIIIB variant, with oval fuselage top, newer machine gun ring mounting, and longer ailerons. R-XIIIA were later converted to R-XIIIB standard, and 49 were made in total (numbers 56.2 to 56.50). The first serial R-XIII was built on June 7, 1932. By March 11, 1933, all were given to the Air Force. In older sources, numbers of 30 R-XIIIA and 20 R-XIIIB could be found.
In 1932, next 170 aircraft were ordered. 48 were built in R-XIIIC variant with minor modifications, then 95 were built in a most numerous R-XIIID variant. It introduced visible changes, like a Townend ring on a radial engine, and a new engine cowling. It also had new type of a machine gun ring mounting. The first R-XIIID was tested in February, 1933. All aircraft were given to the Air Force by March 2, 1935. During repairs, older models A, B and C were modified to R-XIIID standard as well.
In 1933, Jerzy Rudlicki proposed a new design R-XXI, for a new contest for R-XIII successor, but it was not accepted (the contest was won by the RWD-14 Czapla). However, some of R-XXI features, like higher and rounded in cross-section fuselage and changed shape of a tail fin, were found in latest R-XIII variants. Single prototype of the R-XIIIE was built in 1934, fitted with a stronger 360 hp engine Gnome-Rhone 7K Titan, but it was not produced. Another variant R-XIIIF introduced new, Polish-designed 340 hp engine Skoda G-1620A Mors-I. It had no Townend ring on cylinders of the radial engine. After one prototype (no. 56.101), a series of 50 R-XIIIF were ordered in 1934. After seven aircraft had been delivered, the Polish aviation authorities refused to buy nearly completed further 18 aircraft, planning to nationalization all aviation industry in Poland. As a result, Plage i Laśkiewicz factory went Bankruptcy in late 1935, and it was next nationalized under a name LWS ( Lubelska Wytwórnia Samolotów - Lublin Aircraft Works). Then, 18 R-XIIIF, bought by scrap price, were completed, and next series of 32 was built. All R-XIIIF were delivered to the Air Force by 1938. However, only 26 of them were completed with Mors engines (and mostly used for training or staff liaison), while 32 had standard 220 hp Wright engines, lowering their performance to R-XIIID level.
In 1931, one R-XIV was tested on floats, as a seaplane. Since tests came out well, the Polish Navy designated it R-XIII bis/hydro and ordered the next three (nos. 700-703). In 1933, the Navy ordered 10 R-XIII ter/hydro, which was a seaplane variant of R-XIIID (nos. 704-713). Finally, in 1934 the Navy bought 6 R-XIIIG seaplanes, differing in details from a previous variant - among others, a metal propeller (nos. 714-720). They were delivered by April 1935. All variants could also be easily converted to wheeled landing gear.
In 1933, one R-XIIIB was converted to a long-distance sport plane R-XIIIDr, named Błękitny Ptak (the Blue Bird), meant for a flight to Australia, however it was crashed in 1935 in Siam by Stanisław Karpiński. Several aircraft were converted to civilian sport ones, used in Polish Aero Clubs.
12 R-XIII's were converted to blind flying trainers R-XIIIt in 1934, with higher closed trainee cab. Some were converted to simple liaison aircraft, removing armament and mounting a windscreen in the second cab. Several R-XIII were used to tow Military glider, using a special frame with a hook, attached to a fuselage.
The R-XIII prototype was converted in 1932 to an experimental variant R-XIX, with V-tail of Rudlicki's design, but it was not accepted by the authorities, despite it had better field of machine gun fire.
In total, 15 R-XIV and 273 R-XIII were built, including 20 seaplanes.
On the eve of the Invasion of Poland in 1939, the Polish Air Force had about 150 R-XIII. Of them, 49 were in combat units, 30 in reserve, about 30 in training units and about 40 in repairs. In combat units, R-XIII were used in 7 observation escadres (out of 12): numbers 16, 26, 36, 43, 46, 56 and 66. Each escadre had 7 aircraft. The 16th Escadre was in C-in-C reserve, while the others were distributed among the field Armies. The R-XIII was no match for any of the Luftwaffe fighter aircraft, or even reconnaissance aircraft, being much slower, and armed with only one machine gun, but they were actively used for close reconnaissance and Liaison aircraft tasks.
About 40 R-XIII from combat units were destroyed during the campaign, but only part of those were shot down by the German aircraft or flak. During the campaign, 9 aircraft were given to observation escadres as replenishment. Some planes were also used in a wartime improvised units in air bases. About 10 combat aircraft and 7 from other units were withdrawn to Romania. A number of aircraft were bombed by the Germans in air bases or burned by withdrawing Poles. None have survived to today.
In the Naval Air Squadron, 11 R-XIIIter and R-XIIIG floatplanes were used in 1939. The aircraft No. 714 was sent on September 7 at night to search for battleship in Danzig, but did not find it there. The crew claimed to have bombed civilian victory parade in Danzig, celebrating capturing of Westerplatte instead, but there has been no confirmation of such attack found in German sources. On September 8 all planes were bombed, while stationed on the sea near Hel on the Hel Peninsula.
Comparable aircraft:
Combat use
Variants
Description
Operators
Specification (R-XIIIB)
See also
Notes
Bibliography
Further reading
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