PZL P11c...."ugly plane" (?) (1 Viewer)

Ad: This forum contains affiliate links to products on Amazon and eBay. More information in Terms and rules

Some of the above information is not correct. For example Britain sold Hurricanes and Blenheims to the Rumanians and Hurricanes to Yugoslavia.

The PZL P.24 represented the ultimate Puławski-wing fighters. Foreign interest exceeded all expectations but a number of potential sales came to nothing for lack of credits and financial backing. It was never ordered by the Lotnictwo Wojskowe, not because they were waiting for the P.50, but because they began to favour the re-equipment of their fighter force with a multipurpose twin-engined, two-seat aircraft, not a dedicated single-seat fighter aircraft. When this decision was later severely criticised the excuse given was that the P.24 was powered by a Gnome-Rhône engine which was not manufactured in Poland and could not be bought in quantity because of a scarcity of foreign currency. This, however, does not stand scrutiny as Poland was given a large armament loan by France and half of it, to be spent in France, remained unused for some time.


The Politics.

The second comprehensive Polish rearmament plan began to take shape immediately after the death of Marshal Piłsudski in May 1935. The LW's expansion proposals were evolved by General Rayski in 1935-36, building on the basis of his three year plan of 1933. The command structure had been split in 1926 into two unrelated peacetime and wartime channels and left the LW without a unified command for its direction and control. Rayski prepared his new plan in a vacuum without any knowledge of any specific defence aims for the air arm or any overall strategic concepts. In fact no such aims existed. The Central Staff, composed of army officers, that had no understanding of air warfare, failed to define clear-cut role for the air arm in a future war. While the army chiefs were completely engrossed with producing detailed plans for a war with the Soviet Union, the air arm was being shaped by the hypothesis of war with Germany.

At that time General Douhet's prophetic theory proclaimed air power, a new and totally independent component of armed strength, as the decisive weapon in any future war. Douhet emphasised the power of the bomber to which, according to him, there was no defence. Some foreign experts forecast the demises of the single-seat fighter. Probably influenced by Douhet's views and Germany's example, Rayski embarked on a vast build-up of Poland's bomber force. He subordinated all other aviation needs to that objective with catastrophic consequences in the fighter-interceptor field.

To meet the requirements of the plan, Rayski authorised the construction of prototypes of six new designs, two each – one interim and one principal service model - for bomber, army support and 'companion' squadrons. A prototype for a single-seat fighter was conspicuously absent. The main equipment of the army support formations was to be provided by a multipurpose, twin-engined, two-seat, dive-bomber/attack fighter, the P.38 Wilk. This design was fundamental to Rayski's rearmament proposals, for in addition to the army support role, the P.38 was intended supplement the LW's bomber potential, provide bombers with fighter protection and contribute to national air defence as a fighter, thereby reducing the need for a conventional single-seat fighter.
Rayski's lack of appreciation for a single-seat fighter was reflected by his curious proposal that the sturdy, all metal P.11 should be replaced by the P.39/LWS.4, a cheap, wire-braced, light-weight monoplane of composite construction. Under his plan this aircraft was to remain in frontline service with fighter squadrons until April 1942, and also was to serve as an intermediate fighter trainer. It could not operate at night or winter conditions, its estimated top speed was 380 km/hr (205 mph) and its practical ceiling was limited to only 1,500 m (4,900 ft). The design contrasted sharply with other Polish projects, all technically advanced, and when, in June 1936, Rayski asked the Government for permission to build the P.39/LWS.4 prototypes, he was refused. In the meantime, the specialist PZL fighter team responsible for the P.7, P.11, and P.24 was dissolved and Wsiewołod Jakimiuk, who led the team after the death of Puławski, was entrusted with the design and development of a twin-engined passenger transport, the PZL 44 Wicher.

Rayski's 1936 plan was not officially endorsed, but served the Central Staff only as the basis for the preparation of their own plan. This was the work of infantry Colonel Jan Jagmin-Sadowski and was ratified at the XVIIth Session of the KSUS (Committee for Armament and Equipment Affairs) on 13th October 1936. The KSUS plan was based on a more conventional tactical concept, which called for new designs for army support and single-seat fighter squadrons and adopted a cautious approach to the new class of P.38 Wilk two-seat fighter squadrons reducing their strength to 100 aircraft. The gap arising from interrupted development of a single-seat fighter to succeed the P.11 proved difficult to close.

Feasibility studies in the light-fighter field were to be expanded and in addition to some further work on the improved P.39/LWS 4 project, a superior PZL design, the P.45 Sokół, proposed by Kazimierz Korsak, was investigated in detail. Later, two more competitive designs, the PWS 42 and RWD 25 entered the Sokół light-fighter programme and although the future of such an aircraft was not yet decided, all three were awarded prototype contracts.

Jakimiuk, still working on the PZL.44, did not begin design studies for an interceptor-fighter, the P.50 Jastrząb, until the winter of 1936-37. His creation was a modern, all-metal, low-wing monoplane, employing a thin aerofoil-section wing and other advanced aerodynamic features. However, the P.50 specification, drafted to Rayski's directives, represented a subtle departure from the KSUS requirement, calling for a fast aeroplane, with manoeuvrability taking second place to speed, capable of carrying a 300 Kg (600 lb) bomb. These were the characteristics of the 'pursuit' fighter, affording insurance against the looming failure of the P.38 Wilk, rather than those of the classic fighter sought by the KSUS. An ill-matched engine, the Mercury VIII radial with a nominal output of only 730 hp and maximum rating of 840 hp, which was forced upon the designer to save time and money, offered little prospects for the fighter's success. The P.50 was hastily ordered off the drawing board into mass order production. PZL received an initial order for 150 Mercury VIII powered examples, which was soon increased to 500, with deliveries of the first 50 to commence in September 1939. The P.50/I prototype was to fly in October 1938 but the late delivery of the Dowty landing gear delayed flight tests until February 1939. The P.50/II prototype adapted to take a more powerful radial of up to 1,600 hp stood idle awaiting the delivery a power plant which remained unspecified until June 1939, when a 925-1,145 hp Bristol Taurus was ordered for it.

At the beginning of July 1936, in a belated move to entrust someone in the GUSZ-controlled 'wartime' command channel with specific responsibilities for air defence, the Inspektorat Obrony Powietrznej Państwa (IOPP, Inspectorate of Air Defence of the State) was created, with Gen Orlicaz-Dreszer, a cavalry officer, appointed its head. Killed in a air-crash twelve days later he was succeeded by Gen Józef Zając, an infantry officer. In the autumn of 1937 a miniscule Air Staff was formed at the Central Staff. This was a new body completely, unconnected with Rayski's Aviation Command in the 'peacetime' channel. The two Air Staffs did not even communicate with each other.

Gen Zając was a novice to aviation but after a few months in office he thought himself qualified to pronounce judgment on intricate questions of operational and equipment policy. Charged with the country's air defence, he began to promote the view that the top priority should be given to development of a fighter force. He completely rejected the proposed building of the bomber force, maintaining that Poland could not afford twin-engined bombers and did not need such aircraft in general, and the P.37 Łoś in particular. He contended that the bomber capability should be provided by the French or British air forces as and when necessary. He began to voice increasingly strong criticisms of Rayski's decisions and opposed the ethos of the KSUS plan which bore the hallmark of Rayski's influence.

In 1936 Zając unveiled his own plan. This envisaged 102 combat squadrons with 900 warplanes by April 1942; 30 single-seat fighter squadrons (300 aircraft), 15 pursuit fighter squadrons (150 aircraft), 22 army support squadrons (220 aircraft), 20 observation squadrons (140 aircraft), and 15 bomber squadrons (90 aircraft) – a large proportion of the bombers to be provided by French or British units stationed in Poland. This coincided with a deepening equipment crisis. Shortages of the P.11 necessitated the retention of the obsolete P.7 in three squadrons. Worse, in early 1938, the P.11 steel engine frames began to crack due to metal fatigue. At the end of November, 1938, Zając prepared a secret defence report on the LW's state of readiness that pinpointed the devastating deficiencies in equipment and stressed that apart from bombers; the situation would worsen in 1939 and would not significantly improve before 1941. He warned that in case of war in 1939 or 1940 the LW would not last longer than two to four weeks.
 
Continued ....

On 14th January 1939 Rayski tended his resignation for the third time. It was accepted on 19th March. He was succeeded by Gen Władysław Kalkus as the Aviation Commander – in the 'peacetime' channel – whilst Zając was nominated to the post of C.-in-C. of the LW in case of war – in the 'wartime channel. To bridge the nonsensical isolation of the two channels, which under the existing salutary government and military structures had to remain separated, Kalkus was made personally responsible to Zając. Zając set about a revision of production programmes in line with his own ideas. Purchases from abroad were to ease the equipment crisis. Steps taken in haste to resolve the crises were rather confusing and haphazard and seriously disrupted production schedules of the Polish aviation industry. Zając wanted to halt the production of the P.37 Łoś at 104 aircraft, but since assembly of an additional 20 airframes had already been transferred to the WP 2 at Mielec, giving the new factory its initial work, they were allowed to be completed. PZL's firm order for 160 P.46 Sum was increased to 300 with the first deliveries expected at the end of 1939. The main production effort of the WP 1 factory,at Okęcie, centred on completion of 42 P.43B reconnaissance bombers ordered by Bulgaria. In March 1939 at the height of the Czechoslovakian crisis, it was briefly intended to retain these for the LW but this decision was soon reversed despite crippling shortages of aircraft in the Karaś squadrons. Amid all this Poland decided to purchase 100 Fairey Battles, aircraft that were generally inferior to the P.43s and less suited to the prevailing operational conditions in Poland.

In the all important fighter field the situation became equally chaotic. Disappointing results of the Mercury VIII-powered P.50/I prototype trials, which proved the aircraft manifestly underpowered, forced Zając to defer large scale manufacture of the fighter, limiting this to the first 30 examples already on the production line. Production was intended to resume later after improvement of the basic design. As a stop gap measure, limited production of new variants of the P.24 or P.11 was considered. Eventually the P.11g Kobuz which utilized the Mercury VIII radial originally intended for the P.50 was selected. An urgent order for 90 P.11g fighters was placed with the PWS factory, which had hitherto specialized in all-wood structures and had no experience of building all-metal airframes. At the same time a new generation PZL fighter, evolved by Jerzy Dąbrowski around a 1,400 – 1,600 hp Hispano-Suiza 12Z upright-V liquid-cooled engine and believed to be designated P.62, progressed to the mock-up stage.

Towards the middle of 1939, Poland, disturbed by German high-altitude reconnaissance flights began frantic attempts to secure speedy delivery of foreign fighters. Several American designs were briefly considered with the Curtiss Hawk 75A (P.36) and Seversky EP-1 (P.35) receiving particular attention. A French armament loan and attractive delivery schedules led to the selection of the Morane-Saulnier MS 406 of which 120 were ordered. The first 20 were ready for despatch at the end of August 1939 and the next 50 were to be shipped in two batches by 1st October. Britain agreed to supply 14 Hurricanes and one Spitfire without delay. One Hurricane arrived and Fairey Battles and a Spitfire were on route when war broke out.

Genesis of the P.24.

Under the terms of a ten year license agreement to build Bristol radial engines, no Polish manufactured Bristol engines could be sold abroad and the Bristol Company had the right to investigate any Bristol-powered aircraft even if the engines for them were supplied by the customer. This did not have much appeal to either PZL or a prospective client. PZL began to consider and advanced fighter variant powered by an alternative make of engine, aimed specifically at export markets. Initial proposals for such an aircraft stressed to take radial engines of 700-1000 hp were put forward by Puławski's successor Wsiewołod Jakimiuk, in February 1932, and the new 700 hp Gnome-Rhône 14Kds radial, the first details of which had just been made available to Poland, was selected as the recommended power plant. Authorisation to proceed with the detailed study for the new model, designated P.24 was given in April.

Except for the adaptation for a more powerful engine and heavier armament, the P.24 was essentially a refined edition of the P.11 and development of both models was closely co-related. To improve the view over the nose, the engine was lowered and pilot's seat raised and moved aft, and the wing's inner sections thinned off, their cut-out deepened and the angle of incidence slightly altered. Parallel modification to the P.11 resulted in the P.11c.

At that time France was engaged in a ambitious programme of fighter development. The resulting ten models employed almost every conceivable configuration for single-seat fighters, all evolved around the Hispano-Suiza 12Xbrs liquid-cooled engine. In addition the French Air Force was considering foreign fighters as possible candidates for licence-manufacture in France and the Polish P.11 was at the top of its list. Gnome-Rhône, developing the new range of powerful 14K Mistral Major radials, was extremely anxious to enter the fighter field, and the PZL fighter presented the firm's only opportunity Gnome-Rhône approached PZL with proposals concerning the development of 14K-powered version of the P.11, offering to contribute up to 150,000 francs towards the cost, supply a free engine, and sponsor the design in the French fighter contest. Coinciding with the work already commenced by Jakimiuk, the offer was accepted. In June 1932, PZL asked for the 760 hp 14Kds radial to be delivered in December. The detailed design for the P.24 was approved and drawings issued to the prototype workshop for the construction of three airframes to begin in July.

Much of the first P.24 prototypeP.24/I came from the P.7a already in production. Unchanged were the wings, rear fuselage, horizontal stabilisers and elevators, rudder and vertical stabiliser. The P.24/II was fitted with a Gnome-Rhône 14Kfs with a nominal output of 900 hp and maximum of 930 hp. PZL stopped producing the P.7a in 1935 when they moved from Mokotow to Okęcie airfield. For this reason it was decided to adapt parts from the P.11. In the autumn of 1935 work was started on the P.24/III prototype which would become the master pattern for series production. The slightly longer wing of the P.11 was used as well as the tail section. The P.24/III probably got its engine from the P.24/II. In November 1936 it was designated the P.24 Super bis and sent to the Paris Salon. Later it was most likely modified and sold to Bulgaria or Turkey as a series model.
 
Mostly the works of Jerzy B Cynk, in particular:

The Polish Air Force at War 1939-45
Polish Aircraft 1893 to 1939.

Also PZL P.24 A-G Andrzej Glass.
 

Users who are viewing this thread

Back