In the last months of 1927, the Aeronautical Department commissioned Central Aviation Works, renamed to the State Aviation Works the following year, to develop a fighter aircraft that could be the successor to the commonly used French SPAD aircraft. Work on the new airframe was begun by engineer Zygmunt Puławski. The first one of the Puławski aircraft family, named P.1 drew the attention of the rest of the world. Then it was the turn of the following P.6 and P.7, all of them aroused interest of foreign constructors and won awards at international air showrooms. In 1930, the Department of Aeronautics ordered to develop a successor for P.6 and P.7. The new PZL P.11 fighter was a one-seat, all-metal, high-wing, full-body undercarriage. The aircraft was characterized by original technical and technological solutions.
The first of them- the wing with an original shape and design- was covered with a small-scale sheet, the so-called Wibault sheet, allowing for low weight, high durability, good aerodynamic properties and excellent visibility from the cockpit to the front and to the sides. This unconventional solution, called abroad the "Polish wing" or "Puławski's wing", gave the patches a characteristic "seagull" shape. The second was a fixed scissor-type chassis, with shock absorbers hidden inside the hull. Also noteworthy was the semi-shell hull structure, previously used on the P.7 fighter, and the main fuel tank that could be ejected from the fuselage in the event of a fire. Work of Puławski, who died the death of an airman in 1931, was continued by engineer Wsiewołod Jakimiuk. The prototype P.11 was flown in 1931 by Bolesław Orliński. Presented in December 1934 at the Paris Air Show, the aircraft aroused great interest among specialists. It was technologically several years ahead of modern constructions.
It was agile, had excellent pilot properties and excellent performance. There were produced 50 aircrafts of P.11a for Polish aviation and 50 P.11b’s (with Gnome-Rhone 9K engine) for export in Romania. The PZL P.11c prototype was flown in the summer of 1934 with the Mercury IV S2 engine., then changed to Gnome-Rhone Mistral. The aircraft in this configuration served as a model for the P.11f license version. Seventy aircrafts of this version were created in the IAR's Romanian facilities. In order to improve the stability, visibility from the pilot's cabin and to strengthen the firepower, a flapper based on the PZL P.11 construction was developed. The new construction has been awarded the PZL P.11c designation. In Poland, 175 P11c fighters were built for the Polish fighter aviation. There were also attempts at a marine version, a winter one with skis and the possibility of bombing from a diving flight. However, they did not go beyond the stages of the projects.
In autumn 1936, the Republican government in Spain tried to buy 36 airplanes, but due to the announcement of the declaration of neutrality by the Polish government, the transaction did not materialize. The next type, P.24, was the last of this family of planes. Thanks to arming in 2 guns and 2 machine guns, it was considered the most strongly armed fighter. In 1937, with the introduction of modern low-wings by other countries, P.11 became an outdated construction.
PZL P.11c was the basic type of fighter aircraft on Polish aviation equipment in September 1939. It has already gave way to the new generation airframe, the German Bf-109. However, thanks to the skills of Polish pilots of "Elevenths", they can count on their account about 120 successful shots.
|Wing span||10,72 m|
|Gross weight||1650 kg|
|Max speed||375 km/h|
|Service ceiling||8000 m|
|Engine||radial 9-cylinder Skoda (lic. Bristol) Merkury VS2 with starting power 600 HP (440 kW) and nominal 565HP (415 kW)|