Time for the last part of the Pre-War Poland chapter.
Of course further chapters will follow. Next two weeks: Polish Air Force in France (1939-1940).
Polish military aircraft 1938-1939
Training Aircraft
RWD-17 was a scaled-down derivative of RWD-8 intended for the next stages of training, first flown in 1937 and produced in series of 23 for civilian flight schools. Trials of the modernized version RWD-17bis, specifically modified to the demands of the military begun in the spring of 1939. Preliminary orders for 50 aircraft were made, with option for 70 more, but only 2 were actually delivered. When the war broke out civilian planes were mobilized and attached to several liason units. Two were evacuated to Latvia and 8 to Romania, where they served until around 1943.
Poland, RWD-17
PWS-33 Wyżeł ("Pointer") was designed as a heavy advanced trainer for the prospective pilots of twin-engined combat aircraft, mainly of PZL-38 Wilk. It featured advanced semi-monocoque wooden construction and was first flown in august 1938. Planned production was to reach 100 aircraft (50 operational and 50 spares). Cancellation of the PZL-38 led to similar fate of PWS-33, although it's development actually continued, with hopes to create of it a combat-viable aircraft. Order was then reinstated in june 1939, but it was too late for series production to commence before war. Of the two prototypes one was destroyed during the aerial bombardment and other was captured by Germans (and presumably later scrapped).
Poland, PWS-33 Wyżeł
PWS-35 Ogar ("Greyhound") was an aerobatics trainer, first flown in 1938. Series of 150 was ordered (later reduced to 50), but problems with weight and stability caused significant delays, and eventually besides two prototypes none were completed and only 17 planes were at various stages of completion.
Poland, PWS-35 Ogar
PWS-40 Junak (roughly: "Brave young man") was a result of a demand for a low-wing monoplane aircraft well suited for the task of training pilots of modern aircraft. Prototype was first flown in april 1939 but destroyed in the bombardment of the PWS factory in the early days of war.
Poland, PWS-40 Junak
Fighters
PZL-38 Wilk ("Wolf") was built as response to a demand for heavy, twin-engined multi-role combat aircraft - an idea popular at the time - that was supposed to replace several types of aircraft (including P.11). It's engines were to be highly advanced Foka engines, but after the death of their talented designer, Stanisław Nowkuński during a mountaineering accident, their development was significantly delayed, forcing the manufacturer of the plane to replace them on the first prototype with US-made Ranger SGV-770B engines (of similar power, but much higher weight). That prototype was first flown in april 1938, and planned engines were installed on second prototype though their performance was found to below expectations, and the project was dropped in favor of PZL-48 Lampart design.
Poland, PZL-38 Wilk
PZL-50 Jastrząb ("Hawk") was a planned replacement for P.11 in the wake of PZL-38 failure and was first flown in february 1939. First prototype with Bristol Mercury VIII engine happened to be underpowered, though after some modernizations it was able to achieve in august 1939 the speed of 500km/h. When the war broke out, the second - somewhat redesigned - prototype was in the final stages of construction, together with several planes of information series. Only flyable PZL-50 was lost on ferry flight on 6 september 1939. It should be noted, that until 2005 only several photos showing just parts of the first prototype, and some sketches made post-war by people involved in the project were known. Therefore most drawings were showing the plane with much tubbier fuselage than in reality. Only the finding of photos showing incomplete second prototype made revision of PZL-50's actual appearance possible.
Poland, PZL-50 Jastrząb
Line Aircraft (Bomber-Reconnaissance)
PZL-46 Sum ("Wels Catfish") was a planned succesor to PZL-23 and was first flown in 1938. Series of up to 300 was planned (with initial orders for 160), but before the war only 2 prototypes were completed. First of them was left behind in Warsaw due to landing gear damage, while second was evacuated to Romania, only to be flown back to Poland (under the pretext of short ferry flight from one Romanian airfield to another) several days later, carrying orders from commander-in-chief of the Polish Army, marshal Edward Rydz-Śmigły to commander of the besieged Warsaw garrison, gen. Juliusz Rómmel. Later the plane was flown to Lithuania where it was interned and later taken over by Soviets. Shortly before the outbreak of war Bulgaria ordered series of PZL-46's with French engines. Additionaly, dive-bomber development (with smaller dimensions, crew of two, inline engine and retractable landing gear) named Łosoś ("Salmon") was under development, but no drawings seem to have survived.
Poland, PZL-46 Sum
Accompanying Aircraft (Observation)
LWS-3 Mewa ("Gull") was planned as an ultimate replacement for R.XIII, with much higher speed, enclosed cockpit and STOL capabilities. First prototype was flown in november 1937 and after trials, in late 1938 200 planes were ordered. However before the war only 2 serial planes were made (with one more completed after the outbreak) and some 20 were nearing completion. Three completed serial aircraft, together with two prototypes were attached to front-line units. Additionaly, LWS-3H floatplane variant was designed for the Navy and LWS-3B variant with French engine was being developed on Bulgaria's order. Planned follow-on to Mewa was LWS-7 Mewa II with new wing and upgraded aerodynamics.
Poland, LWS-3 Mewa
Maritime Aircraft
RWD-17W was a seaplane training aircraft, with stronger engine than land-based version and changeable land and sea undercarriage. Prototype was first flown in 1938 and 5 more were built in 1939, although none (except the prototype) were actually delivered to the seaside due to war.
Poland, RWD-17W
Nikol A-2 was a prototype of a small training, observation and liason seaplane, first flown in march 1939. In september it was captured by Germans and used by them for some time.
Poland, Nikol A-2
Problems with developing a domestic heavy seaplane led the authorities to search for suitable aircraft abroad. In 1938 6 modern CANT Z.506 floatplanes were ordered in Italy, with plans to purchase 12 more. First plane was delivered (by flight) only on 27 august 1939. After the war begun it was evacuated inland to the Siemień lake near Parczew where it was destroyed by an air raid on 11 september 1939. Unfortunately there are no confirmed photos of that plane in intact condition, and just several made by crew of German bomber that destroyed it, with the plane already ablaze and from a distance. There is a possibility, though, that it had blue lightning-stripe on the fuselage.
Poland, CANT Z.506
Unbuilt Aircraft (selected)
In the year 1939 design bureau of PWS created a concept of a fighter aicraft that could be produced in two variants: single- and twin-seater (with moveable vertical stabilizer) - designated Z-36 and Z-37 respectively, powered by GR-14 engine.
Poland, PWS Z-36 and Z-37
PWS Z-49 of 1938 was a design of advanced combat trainer.
Poland, PWS Z-49
RWD-22 was projected combat floatplane capable of torpedo and bomb attack and reconnaissance duties.
Poland, RWD-22
RWD-25 was one of the light figter designs under development in Poland in 1939. Works on it were relatively least advanced in august 1939.
Poland, RWD-25
PZL-45 Sokół ("Falcon") was another light fighter design of late 1930s. Before the war a full-scale mock-up was made and work on prototype has begun, with plans to fly it in early 1940.
Poland, PZL-45 Sokół
PZL-48 Lampart ("Leopard") was a scaled-up development of PZL-38 Wilk, adapted for
GR Mars 14M05 engines, When the war broke out, construction of prototype was taking place, scheduled to complete in 3-4 months time. Further development, PZL-54 Ryś ("Lynx") was planned, as much larger plane (closer in size to PZL-37 Łoś bomber) with inline engines and top speed of 640km/h. Unfortunately there are no actual drawings of it (and those around the net are only post-war speculative fan-arts).
Poland, PZL-48 Lampart
Planned follow-ons to the PZL-50 were PZL-53 Jastrząb II and PZL-56 Kania ("Kitty Hawk"). First of them was planned to have either
PZL Waran or
GR 14N21 engine and redesigned tail. Second was planned to have inline
Hispano-Suiza 12Y engine. Unfortunately, there seems to be no surviving actual drawings of these. Those in circulation are based on speculative drawings made around 1988 by Chuck Davis and themselves based on the then-available data about PZL-50's first prototype. Finding in 2005 photos of PZL-50's second prorotype made them somewhat questionable.
Poland, PZL-53 Jastrząb II, PZL-56 Kania
PZL-55 (often errroneously referred to as PZL-62) was a project by Jerzy Dąbrowski of advanced fighter with
Hispano-Suiza 12Z engine and armed with 6-8 machine guns. Various sources give conflicting data regarding size of that design (between 8,5 to 9,64m of length, with the largest size being given most often). In 1943, when Jerzy Dąbrowski was serving in technical department of Polish Air Force HQ in Great Britain he created a project of training/sports/liaison plane based on PZL-55 layout, called Gazela ("Gazelle"), planned to be built in Poland after liberation. However history took somewhat different path and eventually that project was redesigned again and served as basis for - eventually unbuilt - Percival P.68 Gazelle AOP plane.
Poland, PZL-55, PZL/Dąbrowski Gazela
Other designs of 1918-1939 period
1919
Sakowicz S-III - Leon Wayde-Sakowicz was a member of the design/managerial staff of the Lwow military aviation depot. During his work there he created a preliminary design of a VSTOL aircraft with two engines, supposedly capable of carrying up to 12 men or equivalent weight of armament. His proposal to the Air Force HQ met with no interest, but apparently it wasn't officialy declined, which was understood by the designer as a green light to start construction. Eventually, however, reorganization of the depot led to cessation of this extra-curricural project, of which no further details are known.
Szweda - Paweł Szweda vel Paul Schwede was a radiotechnical engineer active in Germany, who in 1919 offered to Polish air force a design of a radio-controlled bomber-reconnaissance drone. Unfortunately, although the designer had actual experience in the area, the idea seemed too advanced for the military and wasn't put into development.
Wentzel I - Włodzimerz Wentzel from Ostrów Wielkopolski was an owner of a factory producing aircraft propellers and some other aeronautical equipment. Together with Emil Kurzeja he designed in 1919 a reconnaissance-bomber biplane aircraft powered by 200hp RAPP engine. Although Wentzel's design was met with significant interest from military authorities - not least because his products were known for quality - they were skeptical about possibility of upgrading his relatively small facility into a full scale aeroplane factory and idea was eventually shelved.
Zalewski WZ-VII - Władysław Zalewski, after his return to Poland, designed a small quadruplane fighter designated WZ-VII. Military aviation expresed some interest, but despite it's potential as highly agile dogfighter, eventually acknowledged certain technical challenges that could nullify the advantages and cancelled the project. Unfortunately, to this day only a front-view of the proposed plane survived.
1921
ARLA-I - When in 1920 Zakłady Mechaniczne Plage i Laśkiewicz in Lublin were awarded a contract to produce Ansaldo A.1 and A.300 airplanes for the Polish air force, they were also ordered to design their own multi-purpose combat aircraft. Design was completed year later and designated ARLA-I (acronym from the names of the then-heads of company Arkuszewski and Laśkiewicz), but after the evaluation the air force decided not to order a prototype.
1923
ARLA-II - In 1923 Plage i Laśkiewicz works were ordered to create another multi-purpose combat aircraft, this time as an advanced derivative of Hansa-Brandenburg C.I, but the design works showed that air forces' expectations about the necessary changes of an already very outdated design were both over-optimistic as well as somewhat contradictory, and project was eventually cancelled.
1925
Wojciechowski Wujot - In 1924 military aviation organized contest for military aircraft designs (in several categories), which a year later was won in fighter category by Bartel BM-1 (which, however, was never built - like basically all the other designs from the contest). Second highest score in the contest was gained by design Wujot by Jerzy Wojciechowski which was a monoplane of metal construction, powered by 500hp engine.
Drzewiecki DK - another design from fighter contest was made by Jerzy Drzewiecki (of later RWD fame) and was an aerodynamically well-developed sesquiplane twin-seater with 450hp Lorraine-Dietrich engine.
Brodowski Jupiter - final design from that contest was a twin seater heavy fighter designed by Feliks Brodowski, which apparently was something akin to scaled-down Breguet XIV.
Puławski Scout - in the bomber-reconnaissance (army co-operation) category the winner was a design by Zygmunt Puławski, then a student of the last year of the Politechnika Warszawska. It was a twin-seater biplane with Lorraine-Dietrich 450hp engine.
Rudlicki R.VII Odwet - Jerzy Rudlicki in 1925 was a member of the Polish military-technical committee tasked with purchase of aircraft in France. While there he created for the mentioned contest a design of a night bomber plane with biplane configuration, two engines, armed with 5 machine guns and 1000-1200kg of bombs and built from non-strategic materials to reduce costs and technological difficulties. Plane was named
Odwet (Revenge) and its plans were sent to Warsaw from France by normal post in elaborate envelope with fancy seals on it and large sign "Odwet" on it. For some strange reason this
totally inconspicuous package with highly confidential content was never delivered and investigation at the post office gave no results.
Sztygold Orlę - in the initial trainer category the '24 contest was won by the design by Maurycy Sztygold, named Orlę (Eaglet). It was a simple wooden monoplane with both seats abreast and powered by Anzani 35hp engine.
1926
Bartel BM-3 - the original '24 contest gave no winners in the intermediate trainer category, so an additional contest was organized in 1926. It was won by Ryszard Bartel's design with Austro-Daimler engine, wingspan of 11,77m, length of 7,9m, total weight of 1200kg and maximum speed 182km/h, but due to protracted evaluation process the designer suggested switching to more advanced (using experiences with BM-2 and BM-4) BM-5 design and air forces agreed.
WWS ST-4 - Piotr Tułacz and Augustyn Zdaniewski from WWS Samolot created ST-4 plane, which was however criticized for expected low agility, durability and high cost of production.
PWS-2 - last, and lowest-scoring design from the advanced trainer contest was created by
Podlaska Wytwórnia Samolotów, but the design was deemed to have serious flaws completely precluding any further works.
Sołtycki - In 1926 lt. Sołtycki built in CWL an experimental aircraft with laminarized wing of special construction. No details are known, but apparently the plane was a conversion from Nieuport 80/81/83.
1928
Lublin R.XVII - Shortly after starting his work at ZM Plage i Laśkiewicz in Lublin, Jerzy Rudlicki designed a retractable, manually-operated undercarriage modification of Potez XXV (license-produced at the factory) with wheels retracted outwardly into lower wings ("Spitfire"-way). The arrangement, at a cost of just 30kg of extra weight, gave the profit of 40km/h of speed due to reduced drag.
1930
Dłuski Aerobil Typ 2 - Between 1928 and 1930 Aleksander Dłuski designed a composite "flying car" for army co-operation duties. Although military expressed interest in the design, no construction works were made.
1931
PZL-4B - In an attempt to obtain a replacement for Fokker F.VII bombers, military aviation requested a design of a military variant of PZL-4 passenger plane. However during the design work it was found out that it would necessitate making of a practically wholly new fuselage and whole idea was subsequently dropped.
1933
PZL Górnopłaty Myśliwskie Ciołkosza (Ciołkosz's High-wing Fighters) - Zbysław Ciołkosz designed in 1933 two high-wing fighter concept. First of them had tandem undercarriage, second had it's very wide, with wheels retracted into fuselage. Neither of these were accepted for further development.
RWD-12 - In response to demand on Lublin R.XIII replacement, RWD design team created RWD-12, which was basically a slightly scaled-up, militarized RWD-8 with radial engine. Military was not impressed since it offered little improvement over Lublin, but it served as study for RWD-14/LWS Czapla (which was eventually chosen as the R.XIII replacement).
1934
Lublin R.XXI - Designed for the same purpose as RWD-12, was an advanced upgrade of R.XIII (based on R.XIIIDr), and while unsuccessful at the contest, parts of the design found their way to late-model R.XIIIF.
Lublin R.XXII - Dissatisfied with limited capabilities of naval version of Lublin R.VIII, military authorities demanded a torpedo-bomber aircraft and while the main effort was put on heavy twin-engine designs (Lublin R.XX, PWS-62 and PZL-18), Plage i Laśkiewicz works received also an order for a smaller, single-engined aircraft. Design created in response was heavily influenced by Vickers Vildebeest, but after only several months navy lost interest and cancelled the project.
1935
PZL Rozpoznawczy Wysokiego Pułapu (High-altitude Reconnaissance) - In 1935 PZL conducted an internal study for fast, high altitude recon plane of all-metal construction, crew of two and two engines.
PWS Z-47 Sęp III - It was an advanced/operational training variant of Z-17Sęp III fighter project.
1936
PZL MDL Dalekiego Wywiadu (Naval Air Wing Long-Range Reconnaissance) - In 1936 PZL conducted an internal study for long-range naval recon aircraft. No details are known.
PZL Myśliwski Dwubelkowy Korsaka (Korsak's Twin-boom Fighter) - Kazimerz Korsak was a member of the PZL-38 Wilk design team and also created an alternative concept design of a twin-boom, single-engine (with pusher propeller) fighter with tricycle landing gear and heavy armament concentrated in nose (apparently roughly similar in concept to later SAAB J-21).
1938
PWS-28 - it was a modification of PWS-27 design with Avia Delfin 3T or G-1620A Mors engine.
1939
LWS-7 Mewa II - Already before the LWS-3 army co-operation plane entered service, the works on it's succesor were started. The Mewa II was an upgrade of it's predecessor with new wing, new engine (PZL-Bristol Pegaz XX, later to be replaced by PZL Waran) and more aerodynamically refined fuselage. After the outbreak of war the plans were transferred for safekeeping to Bulgaria, and according to some sources have significantly influenced the KB-11 Fazan aircraft.
PWS-36 - Concept design of a light and inexpensive airplane for aeroclubs and potentially also for military liaison duties, broadly inspired by Belgian Tipsy aircraft.
PWS-41 - Planned introduction of PZL-46 Sum bomber-recce aircraft into service created a demand for an advanced/operational trainer for their future crews, which was to be a wooden low-wing monoplane with fixed undercarriage.
PWS-42 - Design belonged to the same category of light fighters as PZL-45 and RWD-25, and thanks to relatively powerful GR-14 engine and careful aerodynamical design was expected to achieve relatively high speed.
PWS-46? -60? - Shortly before the war PWS design burea started work on high-speed bomber aircraft with twin-fuselage configuration (akin to later P-82 Twin Mustang). Not much details are known, but probably aicraft was to be of wooden construction, powered by two PZL-Bristol Mercury engines.
PZL-44B - In an attempt to make a production of PZL-44 Wicher passenger plane more economical (and therefore to preserve domestic design and construction capacity of aircraft in that size category), military aviation leadership planned to order several long-range reconnaissance aircraft (with limited bombing capability) based on it, designated PZL-44B. The plane was supposed to have minimal changes compared to civilian version and very weak defensive armament (of 3 machine guns), relying mostly on speed. When gen. Rayski left his post as head of military aviation the plan was cancelled.
PZL Rozpoznawczy Dalekiego Zasięgu (Long-range reconnaissance) - shortly before the outbreak of war, PZL begun work on long-range recon aircraft, probably based on PZL-46 Sum.
PZL Łosoś (Salmon) - also in 1939 design works begun on fast, light bomber with dive-bombing capabilities. Apparently it was something like downscaled PZL-46, with crew of two, retractable undercarriage and Hispano-Suiza inline engine.
RWD-24 - It was a planned land-based light bomber and training version of RWD-22 torpedo floatplane.
RWD-26 - It was a planned civilian version of the RWD-23 military trainer.
Sources:
Cynk Jerzy B., Polish aircraft 1893-1939, London 1971;
Glass Andrzej, Polskie konstrukcje lotnicze 1893-1939, Warszawa 1977;
Morgała Andrzej, Samoloty wojskowe w Polsce 1918-1924, Warszawa 1997;
Morgała Andrzej, Samoloty wojskowe w Polsce 1924-1939, Warszawa 2003;
http://www.samolotypolskie.pl