P.Z.L. P.8 was a fighter designed by Ing.

Zygmunt Puławski Zygmunt Puławski (October 24, 1901 – March 21, 1931) was a Polish aircraft designer and pilot. He invented a gull-wing aircraft design, also known as "Puławski wing" and designed a series of Polish PZL fighters. He was born in Lublin. In ...

and constructed by P.Z.L. (''Państwowe Zakłady Lotnicze'' - National Aviation Establishments) from 1930.

Design and development

The P.8 was loosely based on the P.1, retaining the slab-sided fuselage and strut braced gull wing characteristic of Pulawski's fighters throughout the 1930s. Despite official preference toward radial engines Pulawski won authority to develop a new fighter powered by V-12 engines up to . The two fighter designs which emerged were designated P.8 and P.9, re-using the designations of two seaplane designs that had been rejected by the Polish Navy. Two power-plants were fitted to the two prototypes; the P.8/I was fitted with a

Hispano-Suiza 12Mc The Hispano-Suiza 12M was one of two new V-12 engine designs first run in 1927–1928. It produced about 375 kW (500 hp), was the first to use gas nitride hardening and introduced wet cylinder liners into Hispano-Suiza's aircraft engi ...

; the P.8/II was fitted with a Lorraine 12Hfrs Pétrel Chasse. The airframe of the P.8 continued Pulawski's theme of semi-monocoque stressed skin Aluminium alloy structure with fabric covered control surfaces. The wings were built up around two I-section Aluminium alloy spars with alloy ribs and finely corrugated sheet

Duralumin Duralumin (also called duraluminum, duraluminium, duralum, dural(l)ium, or dural) is a trade name for one of the earliest types of age-hardenable aluminium alloys. The term is a combination of '' Dürener'' and ''aluminium''. Its use as a tra ...

. High set gull style wings were attached to the upper fuselage with about 5 degrees dihedral out to the joint between centre-section and outer wings which had zero dihedral. Support for the wings came from pairs of struts attached to the lower fuselage and at the thickest section of the outer wings at about 1/3span. A fixed tail-wheel undercarriage consisted of strut mounted mainwheels attached to the fuselage at the wing strut attachment points and a steel shod tail-skid. Cooling for the engine was achieved by a large radiator bath under the rear fuselage on the P.8/I and by special surface heat exchangers under the rear fuselage of the P.8/II. The special heat exchangers caused cooling difficulties and were replaced by small radiators either side of the rear fuselage aft of the cockpit. Flight testing of the first prototype began in 1931, with the second prototype following in 1932, competing in that year's International Air Meeting in

Warsaw Warsaw ( pl, Warszawa, ), officially the Capital City of Warsaw,, abbreviation: ''m.st. Warszawa'' is the capital and largest city of Poland. The metropolis stands on the River Vistula in east-central Poland, and its population is officia ...

and the 1932 Salon de l'Aeronautique at

Paris Paris () is the capital and most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), making it the 30th most densely populated city in the world in 2020. S ...

. The P.8/I was also due to appear at the 1932 Zurich Meeting, replacing the P.8/II but was damaged beyond repair during a landing at

Innsbruck Innsbruck (; bar, Innschbruck, label=Bavarian language, Austro-Bavarian ) is the capital of Tyrol (state), Tyrol and the List of cities and towns in Austria, fifth-largest city in Austria. On the Inn (river), River Inn, at its junction with the ...

. Beset by cooling problems and with the death of Pulawski in 1931, the Department of Aeronautics could not be persuaded to continue with development of V-12 powered fighters, continuing development of the radial engined P.Z.L. P.7. Production versions of the P.8 would have been designated P.8 for Hispano-Suiza powered versions, P.9 for Lorraine Pétrel powered versions and P.10 for a proposed

Rolls-Royce Kestrel The Kestrel or type F is a 21 litre (1,300 in³) 700 horsepower (520 kW) class V-12 aircraft engine from Rolls-Royce, their first cast-block engine and the pattern for most of their future piston-engine designs. Used during the interwar pe ...

powered derivative.

Variants

;P.8/I :The first prototype powered by a

engine. ;P.8/II :The second prototype powered by a Lorraine 12Hfrs Pétrel Chasse engine. ;P.9 :Production version of the P.8/II, powered by a Pétrel engine. ;P.10 :A proposed version to be powered by a

engine.

Specifications (PZL P.8/II)

References

{{PZL aircraft Gull-wing aircraft PZL aircraft Single-engined tractor aircraft Aircraft first flown in 1931

Design and development

Variants

Specifications (PZL P.8/II)

See also

References