The Lublin R-XIX was an experimental aircraft that saw a ‘V’ tail installed on a R-XIII liaison aircraft with successful but unappreciated results.
The idea of a ‘V’ tail was suggested by Jerzy Rudlicki, one of the most gifted designers working at Lublin. The normal combination of vertical and horizontal tail surfaces would be replaced with a ‘V’ shaped tail, which had two tail surfaces sloping upwards at an angle. The aim was to improve the field of fire for the observer in the rear cockpit. In theory the arrangement could also reduce drag, although the two angled surfaces tend to end up with a similar surface area to a conventional tail for the same aircraft.
Early in 1931 Lublin began work on installing the ‘V’ tail onto a Polish built Hanriot H.D.14 biplane. This aircraft then became the first aircraft in the world known to have flown with this type of tail. These trials, in the summer of 1931, passed off successfully.
The success of the tests with the Hanriot encouraged Zygmunt Zakrzewski, the managing director of the Lublin works, to approve a V-tailed version of the R-XIII. However the Polish Department of Aeronautics wasn’t interested, so the project continued as a private venture.
Work started with wind tunnel trials at the Warsaw Aerodynamic Institute to compare various ‘V’ and ‘A’ shaped tails (the ‘A’ having horizontal surfaces sloping downwards and no vertical surface). The ‘V’ tail was found to be superior, so late in 1931 work began on installed it on the R-XIII prototype, which was back at the factory to be brought up to service standards.
This aircraft made its maiden flight in the summer of 1932, and was then sent to Warsaw to be demonstrated at the I.B.T.L. (Research Institute of Aviation Technology). It so impressed Colonel Kossowski of the Polish Air Force that he took the prototype R-XIX up for a flight himself, and ended the flight highly impressed.
Unfortunately at this point the Department of Aeronautics stepped in. Lublin were fined for having failed to deliver the overhauled R-XIII back to the Air Force on time, while Kossowski was reprimanded for flying the experimental aircraft without permission. The Department went even further, and had the tail sawn off and the rest of the aircraft sent back to Lublin without it! Unsurprising this ended all work on the idea.