The Lublin R-XIII was the main Polish army-cooperation plane (observation and liaison plane) of the Polish Air Force, designed in the early-1930s in the Plage i Laśkiewicz factory in Lublin. In 1927, the Polish aviation authorities announced a contest for an army-cooperation plane (in Polish: samolot towarzyszący, literally: “acompanying plane”). In Polish doctrine it was a close reconnaissance, observation and liaison aircraft, operating from casual airfields, providing big Army land units with information about the enemy. According to its requirements the aircraft was to use a Wright 220 hp engine, armed with a machine gun, have a speed of 170 kph and short takeoff and landing. The PZL state factory proposed the PZL Ł-2, built in a series of 25 aircraft, while private factory Plage i Laśkiewicz in Lublin proposed the Lublin R-X, designed by Jerzy Rudlicki. It was flown on February 1, 1929. Five aircraft were built for the Air Force as R-Xa, and one was built as a long-distance sports plane. The third competitor was the PWS-5t2.

The contest was won by the R-X, 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 cockpits 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. The first, number 56-1, had a wing with short chord as R-XIV and reduced vertical stabilizer, a raised tubular, arc półobrotnice machine gun, and rear fuselage was flat from the top. First flown in June 1931, but in July of that year, during rehearsals in IBTL, as a result of intense acrobatics the joystick fixing pin was beheaded. The pilot, deprived of control, parachuted, and the aircraft made a normal landing on a field and stopped in a ditch. The R-XIII No. 56-1 became the model for a series of Lublin R-XIII. The second was Lublin R-XIV No. 54-15. The aircraft received km T0.7 turntables and rounded up the rear fuselage. 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 and was designated the Lublin R-XIII. The first five machines were designated R-XIIIA and naturally differed from the prototype. In the spring of 1932 the aircraft was put on 54-15 floats and became the prototype for a future series of such machines. 54-15 aircraft became the prototype serial Lublin R-XIIIB.

The aircraft was of mixed construction (steel and wood) and a monoplane, conventional in layout, with braced high wings, canvas and plywood covered (the front part of the fuselage was metal covered). A conventional fixed landing gear, with a tailskid was fitted. The Crew of two sat in tandem in an open cockpit, with twin controls. The observer had a 7.7 mm Vickers K or Lewis machine gun on a ring mounting (rarely, 2 machine guns). The aircraft could be fitted with racks for small bombs of 12–25 kg. A 9 cylinder air-cooled Wright Whirlwind J-5 radial engine (produced in Poland) with 162 kW (220 hp) nominal power and 176 kW (240 hp) take-off power (on 22 aircraft R-XIIIF, 250 kW (340 hp) engine Skoda G-1620A Mors-I wad fitted). A Two-blade wooden or metal propeller was also fitted. A 200 liter Fuel tank in the fuselage could be dropped in case of fire emergency (R-XIV – 135 liter tank).

The Lublin R-XIII drew attention from abroad. Requests for a proposal were received from Romania, Aero Club of Belgium and Spain in 1931. Sales did not eventuate.

On July 21, 1931, 50 R-XIII aircraft were ordered. The first series of 30 were designated R-XIIIA, the next 20 were R-XIIIB. Both variants differed mostly in a type of a machine gun ring mounting. The first serial R-XIII was built on June 7, 1932. By March 11, 1933, all were given to the Air Force.

The first 5 units built as R-XIII (No. 56-2 to 56-6) were identical with the prototype 56-1 for the Department of Aeronautics. They were XIIIS-R, or according to one source, reconstructed version of the four-XIIIB R, R-XIIIc one and three R-XIIID. These airplanes were then transferred Aeroklubowi Polish Republic. One of these aircraft (No. 56-51) was converted to version rally marked initially Lublin R-XXIII and later Lublin R-XIIIDr. Later, it was modified for the R-XIIIB. Another 25 aircraft of the turntable TO-7, received the designation R-XIIIB (numbers 56-7 to 56.32), and another 20, also designated R-XIIIB (numbers 56-33 to 56-52), received a turntable Rudlickiego R-2. A total of 49 units were built. In 1933, four of the R-XIIIB were delivered to military flying clubs. The aircraft received the following civil designation SP-AFD (# 56-12), SP-AND (# 56-13), SP-ANF (# 56-20) and SP-AKK (# 56-48).

On 12-28 April 1933 two civilian R-XIII took part in the rally on the Balkan route Warsaw-Lwów- Czerniowce- Jassy- Bucarest Sofia- Belgrad- Zagrzeb- Vienna- Bratysława- Praga- Brno- Warsaw.

In December 1932, on request of the Department of Aeronautics, Eng. J. Rudlicki prepared a draft of a modified R-XIII, designated Lublin R-XXI. The engine was a Polish PZL G-1620 “Mors II.” In September 1932 the Department of Aeronautics ordered two prototypes R-XIII also with the Mors engine, designated Lublin R-XIII and Lublin R-XIIIF.

In September, 1932 the Department of Aeronautics ordered 120 R-XIII, including 50 R-XIIIc 70 and R-XIIID. 48 were built in R-XIIIC variant with minor modifications (No. 56-52 to 56-99), delivered in May 1933-January 1934, 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 with adjustable shutter. It also had new type of a machine gun ring mounting, besides the length of the aircraft increased by 0.25 m. On January 9, 1932 an order was placed for three R-XIIIbis / hydro with wooden floats – for naval aviation. The planes were built in 1932 and at the end of the year transferred to the customer. The aircraft had removable undercarriage, allowing them to use airfields.

In February of 1934 the number of aircraft was increased from 120 to 170, including 48 R-XIIIc prototype R-XIII and prototype XIIIF R-95, R-XIIID and 25 aircraft of the G-1620 engine version.

The first R-XIIID (No. 56-102) was submitted to the IBTL tests in February, 1933 and then two more aircraft. They received civil registration SP-ANE, -ANG, – AMG. The first six of the D series were converted for displays in 1933. The aircraft left from Warsaw on September 3 to go to Moscow to participate in the celebrations of the 16 anniversary of the October Revolution, but due to the difficult weather conditions only flew to Minsk and then the visit was postponed. R-XIIID (numbers from 56-102 to 56-196) were supplied the army in by March 2, 1934. From the middle of the series the mounted turntables were type SS-32 bis. Three copies of R-XIIID without the turntable, were received in 1934 by the Aero Club of the Polish Republic. The Flight Training Center at Deblin had four R-XIIID converted to blind flying in the field. 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 the R-XXI features, like the higher and rounded in cross-section fuselage and a changed tail fin shape, were found in later R-XIII variants. A single prototype of the R-XIIIE was built in 1934, fitted with a more powerful 360 hp engine Gnome-Rhone 7K Titan engine, but it was not produced. Another variant, the R-XIII-F introduced new, Polish-designed 340 hp engine Skoda G-1620A Mors-I engine. It had no Townend ring on cylinders of the radial engine. After one prototype (no. 56.101), a series of 50 R-XIII-F’s were ordered in 1934. After seven aircraft had been delivered, the Polish aviation authorities refused to buy a further 18 nearly-completed aircraft, as they were planning to completely nationalize the aviation industry in Poland. As a result, the Plage i Laśkiewicz factory went bankrupt in late 1935, and it was next nationalized under the name LWS (Lubelska Wytwórnia Samolotów – Lublin Aircraft Works). The 18 R-XIIIF, were them bought at scrap price, were completed, and the next series of 32 was built. All R-XIII-F’s were delivered to the Polish Air Force by 1938. However, only 26 of them were completed with Mors engines (and these were mostly used for training or staff liaison), while 32 had standard 220 hp Wright engines, lowering their performance to R-XIII-D level.

In the early 1930s the R-XIII was quite a successful plane for its purpose. It had a very short take-off (68 m for R-XIIIA) and landing, enabling it to operate from rough fields and meadows. However, only some of R-XIIIs were equipped with a radio and a camera, which lowered their usefulness. In 1932-1936 they were used in three-aircraft liaison platoons, being the basic Polish army-cooperation plane. In 1937 they were formed into army-cooperation escadres (eskadra towarzysząca), in 1939 reformed into observation escadres (eskadra obserwacyjna). In 1939 some of the R-XIII’s were replaced by the RWD-14b Czapla, which was not much more modern. A planned replacement was a modern LWS-3 Mewa, but it was not introduced prior to the outbreak of war.

Four R-XIIIB were adapted for passenger transport as the R-XIII (sztabowy).

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). On 5 May 1933, the Navy ordered 10 R-XIII ter/hydro with KZA type floats, which was a seaplane variant of R-XIIID (nos. 704-713). In the spring and summer of 1934, these machines entered service with Squadron Pinsk River Flotilla, based in Pinsk.

Finally, on 26 May 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.

One machine of this series was modified, designated R-XIIIDr, with a rear cabin for passenger transportation. The aircraft was originally intended for the long trip to Australia, so in addition to enlarged fuel tanks, it had a Sperry attitude indicator and other navigation equipment. Flight range of the airplane was 2,500 km. However, May 10, 1933 during a routine test flight of the aircraft involved in an accident.

In April 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. The main difference was additional fuel tanks that allow a 2,000 km range, a Townend ring, metal propeller and radio. It was crashed in 1935 in Siam by Stanisław Karpiński. Several aircraft were converted to civilian sport ones, used in Polish Aero Clubs.

In preparation for the Challenge 1934, six R-XIIIB were adapted for blind flying training with higher closed trainee cabin. These were designated R-XIIIt. Completed by June and July 1934, these aircraft were used by the Polish team for the Challenge, practicing at Warsaw. They made Warsaw-Paris and Paris-Warsaw without landing on the route. The aircraft were returned to the Air Force.

Two more R-XIIIB were converted into a version of the R-XIIIt. Probably at the Training Centre of Aviation in Deblin three or four copies of the R-XIIID also converted. Approximately 17 R-XIIIt were built, including 11 from R-XIIIB, and five from XIIIc R-1 and F-XIIID. Several copies of the R-XIII unarmed version served on 1 5 Squadron Aviation Regiment in Warsaw.

Several military R-XIII were also used to tow gliders, using a special frame with a hook, attached to a fuselage. In May 1933 at the Warsaw International Airport, an R-XIII demonstrated simultaneous towing of three Hall 3 gliders. At the beginning of 1938. They adapted one R-XIII attempts to drop trays of military supplies. Tests carried out in the ITL and 6 GB were successful. Some were converted to simple liaison aircraft, removing armament and mounting a windscreen in the second cabin.

In 1932 the prototype Lublin R-XIII (No. 56-1) was reconstructed to an experimental variant R-XIX and equipped with a “tail Rudlickiego” or “butterfly tail” designed by Eng. George Rudlickiego. It was not accepted by the authorities, despite it had better field of machine gun fire.

In 1934 Eng. Jerzy Teisseyre patented the idea of a vertical tail the drop in flight, in order to increase the field of fire from the position of a rear gunner. To test this idea, in 1935 Eng. J. Teisseyre and Eng. August Bobek Zdaniewski developed structure for the tail and in 1935 PWS built it on a Lublin R-XIIIB. The tail worked properly and, when lowered became an easier way out of a spin. The aircraft underwent IBTL tests and completed successfully. After the tests the aircraft was restored to its original form.

In the Naval Air Squadron, 11 R-XIIIter and R-XIIIG floatplanes were used in 1939. One of them made a night bombing raid on Danzig on September 7, searching in vain for Schleswig-Holstein. On September 8 all planes were bombed, while stationed on the sea near Hel on the Hel Peninsula. On the eve of the Invasion of Poland in September 1939, the Polish Air Force had about 150 R-XIII. Of these, 49 were in combat units, 30 in reserve, about 30 in training units and about 40 in repair workshops. In combat units, the R-XIII’s were used in 7 observation escadres (out of 12), with each escadre having 7 aircraft. The 16th Escadre was the C-in-C reserve, while the others were distributed among the Field Armies. The R-XIII was no match for any of the Luftwaffe fighters, bombers or even reconnaissance aircraft, being much slower, and armed with only one machine gun, but despite this they were actively used for close reconnaissance and liaison tasks.

1933-39 there were a total of 288 aircraft R-XIII and R-XIV, including 15 R-XIV, 20 float R-XIII and 253 R-XIII of land (of which 244 220 hp engines). During 1932-1936 created 33 platoons liaison after 3 planes each. In the autumn of 1937. They reorganized the air units, combining the two platoons in the squadron, while eliminating some of them. In 1937-1938, the R-XIII equipped 18 squadrons: 13, 16 and 19 squadron Observation 1 GB in Warsaw, 23, 26 and 29 Squadron 2 GB in Krakow, 33, 36 and 39 Squadron 3 EN in Poznan, 43, 46 and 49 squadron 4 GB in Torun, 53, 56 and 59 squadron 5 GB in Lublin and 63, 66 and 69 squadron 6 EN in Lviv. In addition, it assigned to squadron staffs at 1 GB, IBTL, LSSiB, CWOL / OSL, CWPL and CWTL in Bydgoszcz, and ET in different regiments. During this period, together with airplanes in training and reserve aviation, there were 225 aircraft R-XIII. Since 1936 the R-XIII were to be gradually replaced by the RWD-14 “Czapla”. The delay production RWD-14 resulted in 1939 only five squadrons R-XIII rearmed for “Herons”. Also in 1939, the first LWS-3 “The Seagull” were manufactured which were to replace all the R-XIII in squadrons.

By the end of August 1939. R-XIII remained only 7 squadrons accompanying 5 squadrons equipping the summer of 1939. In the RWD-14 “Czapla” and 6 disbanded at the end of August. In September 1939 16 Observation Squadron was part of the aviation dispositional Supreme Commander. The remaining squadrons were part of the Army Aviation 26 EO in the aviation Army “Kraków” 36 eo – Army “Poznan”, 43 and 46 eo – Army “Pomerania”, 56 eo – Army “Carpathians”. In addition, single copies were in regular or improvised units 63 Squadron Observatory, Pluto Liaison Prime Minister, Pluto Liaison Commander in Chief Air, 3 Platoon Liaison Army Krakow, 11 Platoon Liaison Army Modlin, Team Air Command of the Defence of Warsaw, III Pluto Squadron Exercise Observers SPL Deblin Airbase Małaszewicze, Pluto Liaison Fighter Squadron Ułęż and Group Dubno.

In 1939, the Polish Air Force had 150 R- XIII, including 50 R-XIIID and R-XIIIc in combat units, 30 – in flight schools, 30 in reserve, and 40 to be repaired. About 40 R-XIII from combat units were destroyed during the campaign, but only some of these 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 wartime improvised units from different air bases.

Aircraft with 56 and 59 squadrons of observation 5 EN took part in exercises with the Pinsk Flotilla in 1938, and 23 and 26 observation squadrons took part in the operation Zaolzie within SGO “Śląsk” (21.11-12.121938 r.) in 1939.

In the Naval Air Squadron, 11 R-XIIIter and R-XIIIG floatplanes were used in 1939. One of them made a night bombing raid on Danzig on September 7, searching in vain for Schleswig-Holstein. On September 8 all planes were bombed after two sorties, while stationed on the sea near Hel on the Hel Peninsula.

Among the R-XIII involved in the fighting, approximately 40 were destroyed (and 7 aircraft fell victim to friendly fire), and about 10 combat aircraft and 7 from other units were withdrawn to Romania. 23 R-XIII and XIV-R (including R-XIV No. 54-6, R-XIIIF 58-31, 58-47). Information on aircraft evacuated to Romania are very divergent, they are given numbers: 8, 22, 28 and 33 copies. In Romania, they were used for training until 1944. 19 were destroyed on 16-18 September in order not to captured. A number of aircraft were bombed by the Germans in air bases or burned by withdrawing Poles. One R-XIIID (56-158) landed near Yampol and was captured by Soviet troops. Another plane flew to Slovakia, and another – in Hungary. More than a dozen R-XIII were captured by the Germans.

R-XIII conducted 474 reconnaissance flights and 107 liaison.

In total, 15 R-XIV and 273 R-XIII were built, including 20 seaplanes.

Gallery

R-XIII
prototype (conversion of R-XIV, no. 56.1)
Engine: Skoda Wright J5 Whirlwind, nominal power 162 kW (220 hp) / take-off power 176 kW (240 hp).
Wingspan: 13.25 m
Wing area: 24.5 m 2.
Length: 8.20 m
Height: 2.76 m
Empty weight: 870 kg
Useful load: 430 kg
MTOW: 1300 kg
Max speed: 185 km / h
Cruise speed: 165 km / h
Stall: 85 km / h
ROC: 4.3 m / s
Ceiling: 4120 m
Range: 600 km

R-XIII prototype 54.15
Engine: Skoda Wright J5 Whirlwind, nominal power 162 kW (220 hp) / take-off power 176 kW (240 hp).
Wingspan: 13.20 m
Wing area: 24.5 m 2.
Length: 8.46 m
Height: 2.76 m
Empty weight: 890 kg
Useful load: 400 kg
MTOW: 1290 kg
Max speed: 178.4 km / h
ROC: 3.35 m / s
Ceiling: 4100 m

R-XIIIA
first production version / army cooperation aircraft
30 produced from 1931 (nos 56.2-56.31)
Engine: Skoda Wright J5 Whirlwind, nominal power 162 kW (220 hp) / take-off power 176 kW (240 hp).
Wingspan: 13.25 m
Length: 8.20 m
Height: 2.76 m
Wing area: 24.5 m 2.
Empty weight: 890-910 kg
Useful load: 394-400 kg
MTOW: 1290 to 1304 kg
Max speed: 177-180 km / h
Cruise speed: 146-155 km / h
ROC: 3.3-3.5 m / s
Ceiling: 4120-4100 m
Range: 600 km
Armament: one 7.92-mm Vickers F machine gun
Bombload: Antek SW 16×10.
Radio: RKL / D or Ava N2L / 0
Crew: 2

R-XIIIB
army cooperation aircraft / with an improved turret
20 produced from 1932 (nos 56.32-56.51)
Engine: Skoda Wright J5 Whirlwind, nominal power 162 kW (220 hp) / take-off power 176 kW (240 hp).
Wingspan: 13.25 m
Length: 8.20 m
Height: 2.76 m
Wing area: 24.5 m 2.
Empty weight: 890-910 kg
Useful load: 394-400 kg
MTOW: 1290 to 1304 kg
Max speed: 177-180 km / h
Cruise speed: 155 km / h
ROC: 3.3-3.5 m / s
Ceiling: 4120-4100 m
Range: 600 km
Armament: 1 or 2 moving machine guns Vickers K or Lewis observer cal. 7.92 mm.
Bombload: Antek SW 16×10.
Radio: RKL / D or Ava N2L / 0

R-XIIIC
army cooperation aircraft / with differences on the equipment
48 produced from 1933 (nos. 56.52-56.99)
Engine: Skoda Wright J5 Whirlwind, nominal power 162 kW (220 hp) / take-off power 176 kW (240 hp).
Wingspan: 13.25 m
Wing area: 24.5 m 2.
Length: 8.20 m
Height: 2.76 m
Empty weight: 890 kg
Useful load: 400 kg
MTOW: 1310 kg
Max speed: 180 km / h
Cruise speed: 160 km / h
ROC: 3.5 m / s
Ceiling: 4100 m
Range: 600 km
Armament: 1 or 2 moving machine guns Vickers K or Lewis observer cal. 7.92 mm.
Bombload: Antek SW 16×10.
Radio: RKL / D or Ava N2L / 0

R-XIIID
standard variant of army cooperation aircraft
95 produced from 1933 (nos 56.102-56.196)
Engine: Skoda Wright J5 Whirlwind, nominal power 162 kW (220 hp) / take-off power 176 kW (240 hp). Wingspan: 13.2 m
Wing area: 24.50 m2
Length: 8.5 m
Height: 2.8 m
Empty weight: 956 kg (2,108 lb)
Loaded weight: 1,332 kg (2,930 lb)
Wing loading: 54.36 kg/m2
Maximum speed: 187 km/h
Cruise speed: 155-165 km / h
Stall: 80 – 90 km / h
Range: 600 km
Service ceiling: 4,300 m
Rate of climb: 4.12 m/s
Crew: 2 – Pilot and observer
Armament: 1 or 2 moving machine guns Vickers K or Lewis observer cal. 7.92 mm.
Bombload: Antek SW 16×10.
Radio: RKL / D or Ava N2L / 0

R-XIIIE
one prototype of 1934 with 360 hp Gnome-Rhone 7K Titan engine (no. 56.100)

R-XIIIF
army cooperation aircraft with modified fuselage, part with 340 hp Skoda G-1620A Mors-I engine
58 produced from 1934 (nos. 56.101, 58.01-58.57)
Armament: 1 or 2 moving machine guns Vickers K or Lewis observer cal. 7.92 mm.
Bombload: Antek SW 16×10.
Radio: RKL / D or Ava N2L / 0

R-XIII bis/hydro
seaplane, 4 produced from 1931 (nos. 700-703)

R-XIII ter/hydro
seaplane, 10 produced from 1934 (nos. 704-713)

R-XIIIG
seaplane, 6 produced from 1934 (nos. 714-720)

R-XIIIDr
long-distance sport conversion, 1 made (no. 56.51)

R-XIIIt
trainer conversion, at least 12 made

R-XIV
trainer, 15 produced from 1930 (nos. 54.1-54.15)

R-XV
army cooperation variant of R-XIV, not built

R-XIX
one prototype with V-tail of 1932 (no. 56.1)

R-XXIII
Original designation of the R-XIIIDr.