PWS-40 ''Junak'' (''Junak'' literally means "brave young man") was a Polish trainer aircraft of the 1930s. First flown in the spring of 1939, it was to become the standard training aircraft of the
Polish Air Force
The Polish Air Force ( pl, Siły Powietrzne, , Air Forces) is the aerial warfare 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 16,425 mil ...
's fighter pilot schools before more advanced trainers could be delivered. However, due to the outbreak of World War II only the prototype was completed and test-flown.
A two-seat low-wing monoplane of wooden design, the PWS-40 had a trapezoidal wing covered with plywood and canvass.
[Luto, p.1] The plywood-covered fuselage was equipped with two open cabins.
The plane had a fixed undercarriage.
Design and development
By the mid-1930s the need for a low-wing trainer aircraft became apparent and various Polish manufacturers started submitting designs to the Air Force. In late 1936
Antoni Zagórski of the Warsaw-based
PZL
PZL (''Państwowe Zakłady Lotnicze'' - State Aviation Works) was the main Polish aerospace manufacturer of the interwar period, and a brand of their aircraft. Based in Warsaw between 1928 and 1939, PZL introduced a variety of well-regarded air ...
works designed a simple trainer and sports plane powered by a
Train engine
A locomotive or engine is a rail transport vehicle that provides the motive power for a train. If a locomotive is capable of carrying a payload, it is usually rather referred to as a multiple unit, motor coach, railcar or power car; the us ...
.
In 1937, together with
Jerzy Zbrożek he rectified the design. The modified design was powered by a stronger
Avia 3
Avia Motors s.r.o. is a Czech automotive manufacturer. It was founded in 1919 as an aircraft maker, and diversified into trucks after 1945. As an aircraft maker it was notable for producing biplane fighter aircraft, especially the B-534. Avia c ...
engine (a clone of the
BMW IIIa
BMW IIIa was an inline six-cylinder SOHC valvetrain, water-cooled aircraft engine, the first-ever engine produced by Bayerische Flugzeugwerke AG, who, at the time, were exclusively an aircraft engine manufacturer. Its success laid the foundatio ...
engine) and was named ZZ, after the initials of the designer team.
However, their own company was not interested in the design and in early 1938 it was sold to the
Podlaska Wytwórnia Samolotów
Podlaska Wytwórnia Samolotów (PWS) - ''Podlasie Aircraft Factory'' - was a Polish aerospace manufacturer between 1923 and 1939, located in Biała Podlaska.
History
Podlaska Wytwórnia Samolotów SA was created in 1923. The first aircraft prod ...
(PWS) instead.
The PWS further modified the design, now named PWS-40 Junak, with several features cloned from a
Tipsy S.2
The Tipsy S.2 was the production version of the Tipsy S, a single seat, low wing sports monoplane designed by Ernest Oscar Tips in Belgium in the mid-1930s. It was produced in both the Belgium and the UK.
Background
Avions Fairey, the Fairey Av ...
sports plane bought the previous year for testing; additional influence came from British
de Havilland DH-94 Moth Minor.
The PWS intended the new plane to be a competition for heavier and more expensive home-produced trainers, including
RWD-16 bis and
RWD-23
The RWD 23 was a Polish low-wing trainer aircraft of 1938, constructed by the RWD team, that remained a prototype.
Development
The aircraft was designed in 1938 to fill the gap in the Polish trainer aircraft, by creating a light low-wing traine ...
.
The prototype was test-flown in late April 1939 and delivered to the
Institute of Aviation for further tests.
The design proved promising, but certain teething problems had to be straightened out before serial production. The serial production was to start in the autumn of 1939 both in PWS and in its subsidiary in
Lvov, the
Lwowskie Warsztaty Lotnicze. However, the outbreak of
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
prevented any further works on both the second prototype (under construction by the time the factory was destroyed) and the first series.
The first prototype was captured intact by the Germans, but its further fate remains unknown.
Variants
At the time of the
invasion of Poland
The invasion of Poland (1 September – 6 October 1939) was a joint attack on the Republic of Poland by Nazi Germany and the Soviet Union which marked the beginning of World War II. The German invasion began on 1 September 1939, one week aft ...
the PWS was also working on a thoroughly modernised version of the PWS-40.
Equipped with a much more powerful engine delivering , the new aircraft was to have a smaller wingspan (), flaps and a retractable landing gear.
The designers also envisaged an advanced fighter trainer, armed with machine guns and powered with a engine.
Specifications (PWS-40 Junak)
See also
Notes
References
*
{{PWS aircraft
1930s Polish sport aircraft
1930s Polish civil trainer aircraft
PWS aircraft
Low-wing aircraft
Aircraft first flown in 1939