The PZL P.6 was a pre-WW2 Polish single-seat gull-wing monoplane fighter, designed by Zygmunt Puławski, and manufactured by the Państwowe Zakłady Lotnicze (PZL) state-owned factory. It remained a prototype and did not go into production.

Design and development

Zygmunt Puławski designed the all-metal metal-covered monoplane PZL P.1 fighter in 1928 which was powered with an inline engine, and developed a speed of , but remained a prototype, because the

Polish Air Force The Polish Air Force () is the aerial warfare Military branch, branch of the Polish Armed Forces. Until July 2004 it was officially known as ''Wojska Lotnicze i Obrony Powietrznej'' (). In 2014 it consisted of roughly 26,000 military personnel an ...

decided that its fighters should be powered with a Polish-built

radial engine The radial engine is a reciprocating engine, reciprocating type internal combustion engine, internal combustion engine configuration in which the cylinder (engine), cylinders "radiate" outward from a central crankcase like the spokes of a wheel. ...

. The next model PZL P.6, was powered with a

Bristol Jupiter The Bristol Jupiter is a British nine-cylinder single-row piston radial engine that was built by the Bristol Aeroplane Company. Originally designed late in World War I and known as the Cosmos Jupiter, a lengthy series of upgrades and developme ...

VI FH radial engine. The PZL P.6 flew for the first time in August 1930 with test pilot

Bolesław Orliński Bolesław Orliński (13 April 1899 – 28 February 1992) was a Polish aviator, military, sports and test pilot. He was born on the family estate in Niwerka, Podolia (now Niverka, Kamianets-Podilskyi Raion, Khmelnytskyi Oblast, Ukraine). During W ...

at the controls. It had a very similar wing to the P.1, but the

semi-monocoque The term semi-monocoque or semimonocoque refers to a stressed shell structure that is similar to a true monocoque, but which derives at least some of its strength from conventional reinforcement. Semi-monocoque construction is used for, among o ...

fuselage was completely redesigned with an circular cross-section, and the tail was altered. The modifications reduced the aircraft's empty weight by over .

Technical description

The PZL P.6 was an all-metal

duralumin Duralumin (also called duraluminum, duraluminium, duralum, dural(l)ium, or dural) is a trade name for one of the earliest types of age hardening, age-hardenable aluminium–copper alloys. The term is a combination of ''Düren'' and ''aluminium'' ...

-covered, strut-braced, gull-wing

monoplane A monoplane is a fixed-wing aircraft configuration with a single mainplane, in contrast to a biplane or other types of multiplanes, which have multiple wings. A monoplane has inherently the highest efficiency and lowest drag of any wing con ...

. The forward fuselage was built around a tubular steel frame, while the rear fuselage was a circular semi-monocoque. The tapered two-spar wing which was thinner and narrower at the root was skinned with a ribbed and corrugated Wibault type duralumin sheet, and braced by a pair struts on either side. The open cockpit was provided with a windscreen but no headrest. The

VI FH radial engine mounted in front was fitted with a

Townend ring A Townend ring is a narrow-chord (aircraft), chord cowling ring fitted around the cylinders of an aircraft radial engine to reduce drag and improve cooling. It was patented in 1929, and found use on various aircraft of the 1930s and into the 1940s ...

to reduce drag and used a fixed pitch two-bladed metal propeller. Puławski abandoned the single strut internally sprung legs of the P.1, and used a pair of vees, each braced to the centerline. The fixed undercarriage with a rear skid was conventional and typical of the period. The fuselage had a fuel tank that could be jettisoned in case of an emergency.

Testing and evaluation

The wing design was referred to as the "Polish wing" or "Puławski wing" although it was preceded by the Nieuport Madon, which used the exact same configuration. During a presentation at the

Paris Air Show The Paris Air Show (, ''Salon du Bourget'') is a trade fair and air show held in odd years at Paris–Le Bourget Airport in France. Organized by the French aerospace industry's primary representative body, the ''Groupement des industries frança ...

in Le Bourget in December 1931, the aviation press, such as ''L'Air'', ''The Aeroplane'', ''

Flight Flight or flying is the motion (physics), motion of an Physical object, object through an atmosphere, or through the vacuum of Outer space, space, without contacting any planetary surface. This can be achieved by generating aerodynamic lift ass ...

'' and '' Die Luftwacht'' acknowledged the P.6 as one of the world's top fighter designs. Significantly, the P.6 prototype, piloted by Bolesław Orliński, won the American

National Air Races The National Air Races (also known as Pulitzer Trophy Races) are a series of pylon and cross-country races that have taken place in the United States since 1920. The science of aviation, and the speed and reliability of aircraft and engines grew ...

held in

Cleveland Cleveland is a city in the U.S. state of Ohio and the county seat of Cuyahoga County. Located along the southern shore of Lake Erie, it is situated across the Canada–U.S. maritime border and approximately west of the Ohio-Pennsylvania st ...

between the 29th of August and the 7th of September 1931. The PZL P.6 did not enter production, because at the same time the next improved variant, the PZL P.7 was being developed. The first P.7 prototype retained most design traits of the P.6 with a more powerful supercharged Bristol Jupiter VII F engine, and achieved better performance at higher altitudes. The single P.6 prototype crashed on 11 October 1931 near

Częstochowa Częstochowa ( , ) is a city in southern Poland on the Warta with 214,342 inhabitants, making it the thirteenth-largest city in Poland. It is situated in the Silesian Voivodeship. However, Częstochowa is historically part of Lesser Poland, not Si ...

due to the propeller breaking apart, resulting in catastrophic engine failure. The pilot bailed out successfully.

Variants

* P.6/I : Prototype, which also served as the prototype for the P.7.

Operators

; *

Specifications (P.6/I)

References

External links

Photos and drawings at Ugolok NebaPhoto at Samoloty 1,5
{{PZL aircraft 1930s Polish fighter aircraft PZL aircraft Single-engined tractor aircraft Gull-wing aircraft Aircraft first flown in 1930 Aircraft with fixed conventional landing gear