PZL P.6

The PZL P.6 was a Polish fighter, designed by the engineer Zygmunt Puławski, manufactured by PZL state-owned factory. It remained a prototype.

PZL P.6
Role Fighter
Manufacturer PZL
Designer Zygmunt Puławski
First flight August 1930
Status Prototype Destroyed
Primary user Polish Air Force
Number built 1
Developed from PZL P.1
Variants PZL P.7

Design and development

The history of PZL P.6 started in 1928, when a talented designer, Zygmunt Puławski designed an all-metal metal-covered monoplane fighter PZL P.1. It introduced a high gull wing, giving a pilot an optimal view. The P.1 was powered with an inline engine, and developed a speed of 302 km/h, but remained a prototype, because it was decided, that a fighter for the Polish Air Force should be powered with a radial engine, licence produced in Poland. Therefore, the next model PZL P.6, was powered with the Bristol Jupiter VI FH radial engine.

The PZL P.6 was flown for the first time in August 1930 with test pilot Bolesław Orliński at the controls. It had a very similar wing to the P.1, but the fuselage was completely redesigned with a modern semi-monocoque configuration introduced that was oval in cross-section, as well, the tail was also changed. As a result of the modifications, the aircraft was over 200 kg lighter.

Technical description

The PZL P.6 was an all-metal duralumin-covered, braced, high-wing monoplane. The fuselage was framed in a front section and semi-monocoque in mid and tail sections with an oval cross-section. The two-spar wing of trapezoid shape, thinner by the fuselage, covered with a rimmed Wibault type duralumin sheet, was supported by two struts on either side. The pilot's cockpit was open, with a windshield. The Bristol Jupiter VI FH radial engine mounted in front was fitted with a Townend ring and used a two-blade propeller. The fixed undercarriage with a rear skid was mainly conventional and typical of the period. An unusual feature was a fuselage fuel tank that could be dropped in case of a fire emergency.

Testing and evaluation

The P.6, just like the P.1, garnered a great deal of interest worldwide. Their wing design was called the "Polish wing" or "Puławski wing". During a presentation at the Paris Air Show in Le Bourget in December 1931, the aviation press, such as L'Air, The Aeroplane, Flight 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 in 29 August-7 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 was basically the P.6 with a more powerful Bristol Jupiter VII F engine. With the provision of a supercharger, it achieved better performance at higher altitudes.

The P.6 prototype crashed on 11 October 1931 near Częstochowa due of a propeller breaking apart, resulting in the engine tearing apart. Pilot, Orliński, bailed out successfully.

Variants
  • P.6/I : First prototype, later became P.7 prototype.

Operators
 Poland

Specifications (P.6/I)

Data from Polish aircraft 1893-1939[1]

General characteristics

  • Crew: 1
  • Length: 7.16 m (23 ft 6 in)
  • Wingspan: 10.3 m (33 ft 10 in)
  • Height: 2.75 m (9 ft 0 in)
  • Wing area: 17.2 m2 (185 sq ft)
  • Airfoil: root:IAW-72 (Bartel 37/IIa) (6.5%) ; tip: IAW-72 (Bartel 37/IIa) (8%)[2]
  • Empty weight: 908 kg (2,002 lb)
  • Gross weight: 1,355 kg (2,987 lb)
  • Fuel capacity: 250 l (66 US gal; 55 imp gal) in a jettisonable fuselage tank
  • Powerplant: 1 × Bristol Jupiter VIFH 9-cylinder air-cooled radial piston engine, 340 kW (450 hp)
  • Propellers: 2-bladed Gnome-Rhŏne fixed-pitch metal propeller

Performance

  • Maximum speed: 292 km/h (181 mph, 158 kn) at sea level
285 km/h (177 mph; 154 kn) at 3,800 m (12,467 ft)
  • Minimum speed: 100 km/h (62 mph; 54 kn)
  • Stall speed: 103 km/h (64 mph, 56 kn)
  • Range: 600 km (370 mi, 320 nmi)
  • Service ceiling: 8,600 m (28,200 ft)
  • Rate of climb: 10.3 m/s (2,030 ft/min)
  • Time to altitude: 2,000 m (6,562 ft) in 2 minutes 50 seconds
5,000 m (16,404 ft) in 9 minutes 1 seconds
  • Wing loading: 78.7 kg/m2 (16.1 lb/sq ft)
  • Power/mass: 0.2491 kW/kg (0.1515 hp/lb)

Armament

See also

Related development

Aircraft of comparable role, configuration, and era

References
  1. Cynk, Jerzy B (1971). Polish aircraft 1893-1939. Putnam. pp. 147-154. ISBN 0-370-00085-4.
  2. Lednicer, David. "The Incomplete Guide to Airfoil Usage". m-selig.ae.illinois.edu. Retrieved 16 April 2019.

Further reading
  • Cynk, Jerzy B. History of the Polish Air Force 1918-1968. Reading, Berkshire, UK: Osprey Publishing Ltd., 1972. ISBN 0-85045-039-X.
  • Cynk, Jerzy B. Polish Aircraft, 1893-1939. London: Putnam & Company Ltd., 1971. ISBN 0-370-00085-4.
  • Eberspacher, Warren A. and Koniarek, Jan P. PZL Fighters Part One - P.1 through P.8. (International Squadron Monograph 2). St. Paul, MN: Phalanx Publishing Co., Ltd., 1995. ISBN 1-883809-12-6.
  • Glass, Andrzej. Polskie konstrukcje lotnicze 1893-1939 (in Polish: "Polish Aviation Constructions 1893-1939"). Warszawa, Poland: WKiŁ, 1977. no ISBN
  • Glass, Andrzej. PZL P.7: Cz.1. Gdańsk, Poland: AJ Press, 2000. ISBN 83-7237-080-X.
  • Kopański, Tomasz J. PZL P.7: Cz.2. Gdańsk, Poland: AJ Press, 2001. ISBN 83-7237-081-8.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.