The Lublin R-XXII was a design for a medium sized coastal protection, sea patrol and torpedo bomber aircraft, based on the earlier Lublin R-VIIIbis and which reached quite an advanced stage before the project was abandoned.
The R-VIII had originally been built for the Polish Air Force as a reconnaissance bomber. It was a large single engine single bay biplane, which had made its maiden flight in 1928. The second prototype had performed well at the Tour of the Little Entente and Poland, an aviation event that was held in Prague in August 1928, and five pre-production aircraft had been ordered. However by that time the design was becoming outdated, and the type came last in the 1930 edition of the Tour. The Air Force decided they no longer wanted the type.
At the same time the Polish Navy had asked Lublin for naval aircraft. At first they had suggested licence built versions of Fokker designs, but in April 1930 they suggested a float plane version of the R-VIII. Work on the projected proceeded rather slowly, and a contract to convert the four surviving aircraft wasn’t signed until 26 February 1932. Plans to convert the first prototype were then cancelled, and only three twin-float R-VIIIs entered Polish naval service, in the summer of 1933.
At the same time the Polish Navy was interested in a new medium sized coastal protection and sea patrol aircraft, which could also operate as a torpedo bomber. The Navy was fairly satisfied with the R-VIIIbis, which had just entered service, but this aircraft couldn’t carry a torpedo. On 20 December 1933 Lublin was asked to produce a lighter and more modern version of the R-VIII.
Lublin must already have been working on this project, as they were able to submit the preliminary design on 10 January 1934. The original R-VIII was of wooden construction, but the new aircraft had a welded steel tube fuselage, covered with duralumin panels at the front and fabric at the rear. The pilot had a fully enclosed cockpit, in front of the wings. It had equal span wings, with interchangeable outer panels, based on the lower wing of the R-VIII. The central part of the fuselage could carry fuel tanks, three sets of depth charge racks or a 1,764lb torpedo. A radio operator’s position was behind this section, and the observer’s cockpit further to the rear. The observer’s position had removable emergency controls, a bomb sight and an Eagle III camera. It was armed with a fixed forward firing machine gun, a ventral machine gun and twin machine guns on a ring mounting in the observer’s position. It was to use two duralumin Short floats, which could be replaced with a normal land undercarriage. The final design used a 900hp Hispano-Suize radial engine.
In the spring of 1934 work began on the detailed design, and the naval serial number 805 was allocated to it. However the Navy cancelled the project on 13 June 1934.
Stats (performance figures from design guarantees)
Engine: Hispano-Suiza 14Har 14 cylinder double row radial engine
Span: 45ft 11.5in
Length: 33ft 9.75in
Height: 12ft 6in
Normal loaded weight: 7,430bl
Maximum Speed: 142.9mph (guaranteed)/ 155.3mph for land plane
Climb rate: 2 min 30 sec to 3,280ft
Range: 466 miles
Guns: One fixed forward firing machine gun, one ventral gun, twin guns on observer’s position.
Bomb load: One 1,764lb torpedo or depth charges