PZL P.7

PZL P.7
PZL P.7
Role	Fighter
Manufacturer	PZL
First flight	October 1930
Introduction	1933
Primary user	Poland
Produced	1932-1933
Number built	149+2
Developed from	PZL P.6
Variants	PZL P.11

The PZL P.7 was a Polish fighter aircraft designed in the early 1930s at the PZL factory in Warsaw. State-of-the-art construction, and one of the first all-metal monoplane fighters in the world between 1933 and 1935, it was the main fighter of the Polish Air Force. It was replaced in Polish service by its follow-up design, the PZL P.11c. More than 30 P.7 fighters remained in service during the Invasion of Poland, scoring several kills despite its obsolescence.

The history of the PZL P.7 began in 1928, when a talented designer named Zygmunt Puławski designed an all-metal, metal-covered monoplane fighter, the PZL P.1. It introduced a high gull wing, giving a pilot an optimal view. The wing design was called the "Polish wing" or "Pulawski wing." The P.1 was powered by an inline engine and developed a speed of 302 km/h. But it remained a prototype because a decision was made to use a licence-produced radial engine in the Polish Air Force fighters. So the next model, the PZL P.6, flown in August 1930, was powered by the Bristol Jupiter VI FH radial engine. Both aircraft were well received in the aviation world, with the press recognizing the P.6 as one of the world's top fighters; it won the American National Air Races in August–September 1931.

The PZL P.6 did not enter production because the next variant, the more advanced PZL P.7, was developed. The first prototype was basically the P.6 with a more powerful Bristol Jupiter VII F engine. Due to the use of a supercharger, it had better performance at higher altitudes. The prototype P.7/I was first flown in October 1930 by Bolesław Orliński. Initially, engine cylinders had individual cylinder clearance fairings. After some changes, most noticeably adding a wide Townend ring to the engine and making the tail slimmer, the second prototype P.7/II, built in autumn 1931, was accepted for production with the designation P.7a. It also featured a redesigned wing with slightly increased span, taken from the PZL P.8, and shorter ailerons and smooth upper surfaces, instead of ribbed ones.

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