169-682: The Rogožarski IK-3 was a 1930s Yugoslav monoplane single-seat fighter , designed by Ljubomir Ilić, Kosta Sivčev and Slobodan Zrnić as a successor to the Ikarus IK-2 fighter. Its armament consisted of a hub -firing 20 mm (0.79 in) autocannon and two fuselage -mounted synchronised machine guns . It was considered comparable to foreign aircraft such as the Messerschmitt Bf 109 E and came into service in 1940. The prototype crashed during testing; twelve production aircraft had been delivered by July 1940. Six IK-3s were serviceable when
338-837: A "horrible brutality which is being practiced upon the Croatian People". The appeal was addressed to the Paris-based Ligue des droits de l'homme (Human Rights League). In their letter Einstein and Mann held the Yugoslav king Aleksandar explicitly responsible for these circumstances. Croat opposition to the new régime was strong and, in late 1932, the Croatian Peasant Party issued the Zagreb Manifesto which sought an end to Serb hegemony and dictatorship. The government reacted by imprisoning many political opponents including
507-714: A Germanophile. In the late 1930s, internal tensions continued to increase with Serbs and Croats seeking to establish ethnic federal subdivisions. Serbs wanted Vardar Banovina (later known within Yugoslavia as Vardar Macedonia), Vojvodina , Montenegro united with the Serb lands, and Croatia wanted Dalmatia and some of Vojvodina. Both sides claimed territory in present-day Bosnia and Herzegovina populated also by Bosnian Muslims . The expansion of Nazi Germany in 1938 gave new momentum to efforts to solve these problems and, in 1939, Prince Paul appointed Dragiša Cvetković as prime minister, with
676-591: A Serbo-centric policy increased. In the early 1920s, the Yugoslav government of prime minister Nikola Pašić used police pressure over voters and ethnic minorities, confiscation of opposition pamphlets and other measure to rig elections . This was ineffective against the Croatian Peasant Party (formerly the Croatian Republican Peasant Party), whose members continued to win election to the Yugoslav parliament in large numbers, but did harm
845-535: A Swiss-made Oerlikon FF 20 mm cannon . The replacement engine was less powerful, generating 860 hp (640 kW) at 4,000 m (13,000 ft). German-made Telefunken radios were to be installed but delays meant that only the first aircraft was delivered with a radio. The production aircraft were numbered 2–13; the prototype was number 1. The aircraft were built at the Rogožarski factory in Belgrade and assembled at
1014-453: A combined Bulgarian , Austrian and German force on 6 October 1915. This saw the escalation of South Slavic nationalism and calls by Slavic nationalists for the independence and unification of the South Slavic nationalities of Austria-Hungary along with Serbia and Montenegro into a single State of Slovenes, Croats and Serbs . The Dalmatian Croat politician Ante Trumbić became
1183-485: A few aerobatic tests to determine how good or bad she was. The production test was usually quite a brisk affair; the initial circuit lasted less than 10 minutes and the main flight took between 20 and 30 minutes. Then, the aircraft received a final once-over by our ground mechanics, any faults were rectified, and the Spitfire was ready for collection. I loved the Spitfire in all of her many versions, but I have to admit that
1352-545: A few of the Dalmatian islands were given to Italy. The city of Rijeka was declared to be the Free State of Fiume , but it was soon occupied, and in 1924 annexed , by Italy, which had also been promised the Dalmatian coast during World War I, and Yugoslavia claiming Istria , a part of the former Austrian Littoral which had been annexed to Italy, but which contained a considerable population of Croats and Slovenes. The formation of
1521-505: A general reluctance to adopt new concepts delayed the IK-3, and a contract for the production of the prototype was not signed until March 1937. The company selected for construction was Rogožarski A.D. in Belgrade. The first flight of the prototype was carried out by the VVKJ Test Group towards the end of May 1938 and the aircraft was then flown by a group of VVKJ officers who were to determine
1690-542: A government led by Stojan Protić committed to the restoration of parliamentary norms and mitigating the centralization of the previous government. Their opposition to the former governments program of radical land reform also united them. As several small groups and individuals switched sides, Protić now even had a small majority. However, the Democratic Party and the Social Democrats now boycotted parliament and Protić
1859-505: A group of Muslims from Macedonia and Kosovo, saved it. On 28 June 1921, the Vidovdan Constitution was passed, establishing a unitary monarchy. The pre–World War I traditional regions were abolished and 33 new administrative oblasts (provinces) ruled from the center were instituted. During this time, King Peter I died (16 August 1921), and the prince-regent succeeded to the throne as King Alexander I . Ljubomir Davidović of
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#17330854320802028-498: A jig and the eight horizontal tail formers were riveted to them. A combination of 14 longitudinal stringers and four main longerons attached to the frames helped form a light but rigid structure to which sheets of alclad stressed skinning were attached. The fuselage plating was 24, 20, and 18 gauge , decreasing in order of thickness towards the tail, while the fin structure was completed using short longerons from frames 20 to 23, before being covered in 22 gauge plating. The skin of
2197-479: A large penalty for their fuel injection. When the fuel is fed before the supercharger, as on the Merlin, it evaporates and cools the air by 25°C. This cooling enhances the performance of the supercharger, and increases the power of the engine, with a corresponding increase in aircraft speed, particularly at high altitude." However, the early Merlin engine's lack of fuel injection meant that Spitfires and Hurricanes, unlike
2366-554: A large, fixed, spatted undercarriage powered by the 600-horsepower (450 kW), evaporatively cooled Rolls-Royce Goshawk engine. It made its first flight in February 1934. Of the seven designs tendered to F7/30, the Gloster Gladiator biplane was accepted for service. The Type 224 was a big disappointment to Mitchell and his design team, who immediately embarked on a series of "cleaned-up" designs, using their experience with
2535-502: A low-wing monoplane with retractable landing gear . Contemporary thinking within the VVKJ led them to evolve their initial ideas into a strut-braced gull-wing monoplane armed with a hub -firing autocannon and fuselage -mounted synchronised machine guns . The design concept for what became the Ikarus IK-2 was submitted to the VVKJ on 22 September 1933. With this work completed, Ilić and Sivčev had time to start preliminary development of
2704-506: A lower attrition rate and a higher victory-to-loss ratio than Hurricanes, most likely due to the Spitfire's higher performance. During the battle, Spitfires generally engaged Luftwaffe fighters—mainly Messerschmitt Bf 109E –series aircraft, which were a close match for them. After the Battle of Britain, the Spitfire superseded the Hurricane as the principal aircraft of RAF Fighter Command , and it
2873-499: A maximum rate of 320 per month, making CBAF the largest Spitfire factory in the UK and the largest and most successful plant of its type during the 1939–45 conflict. During the Battle of Britain, the Luftwaffe made concerted efforts to destroy the main manufacturing plants at Woolston and Itchen , near Southampton. The first bombing raid, which missed the factories, came on 23 August 1940. Over
3042-437: A new government led by the neutral figure of Milenko Vesnić. The Social Democrats did not follow the Democratic Party, their former allies, into government because they were opposed to the anti-communist measures to which the new government was committed. The controversies that had divided the parties earlier were still very much live issues. The Democratic Party continued to push its agenda of centralization and still insisted on
3211-568: A new low-wing monoplane that could better meet and defeat the high-performance bomber prototypes then in development by potential adversaries. Ilić and Sivčev's new streamlined low-wing monoplane design had a retractable undercarriage. Like the IK-2 it was initially developed privately by the two men. A scale model was tested in the Eiffel-built wind tunnel in Paris, but the pair soon realised that they needed
3380-498: A one-seater prototype in early July 1939, with its first flight scheduled for late 1941. At the time of the invasion, the production of the IK-5 prototype was well advanced, but it was not pursued either during or after the war. The advanced Yugoslav Ikarus S-49 fighter, produced after World War II, was based on the IK-3. When they entered service, the IK-3 suffered from minor equipment and instrument faults, largely caused by deficiencies in
3549-578: A piecemeal basis. The British public first saw the Spitfire at the RAF Hendon air display on Saturday 27 June 1936. Although full-scale production was supposed to begin immediately, numerous problems could not be overcome for some time, and the first production Spitfire, K9787 , did not roll off the Woolston , Southampton assembly line until mid-1938. In February 1936, the director of Vickers-Armstrongs, Sir Robert MacLean guaranteed production of five aircraft
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#17330854320803718-581: A pretext the political crisis triggered by the shooting, King Alexander abolished the Constitution, prorogued the Parliament and introduced a personal dictatorship (known as the "January 6 Dictatorship", Šestosiječanjska diktatura , Šestojanuarska diktatura ) with the aim of establishing the Yugoslav ideology and single Yugoslav nation . He changed the name of the country to "Kingdom of Yugoslavia", and changed
3887-607: A prominent South Slavic leader during the war and led the Yugoslav Committee that lobbied the Allies to support the creation of an independent Yugoslavia . Trumbić faced initial hostility from Serbian Prime Minister Nikola Pašić , who preferred an enlarged Serbia over a unified Yugoslav state. However, both Pašić and Trumbić agreed to a compromise, which was delivered at the Corfu Declaration on 20 July 1917 that advocated
4056-555: A result, the Spitfire's performance and capabilities improved over the course of its service life. During the Battle of Britain (July–October 1940), the more numerous Hurricane flew more sorties resisting the Luftwaffe , but the Spitfire captured the public's imagination as the main RAF fighter, in part because the Spitfire was generally a better fighter aircraft than the Hurricane. Spitfire units had
4225-446: A similar fashion to a leaf spring ; two of these booms were linked together by an alloy web, creating a lightweight and very strong main spar. The undercarriage legs were attached to pivot points built into the inner, rear section of the main spar, and retracted outwards and slightly backwards into wells in the non-load-carrying wing structure. The resultant narrow undercarriage track was considered an acceptable compromise as this reduced
4394-558: A smaller wing area than the Hawker Hurricane and the Supermarine Spitfire , to achieve a higher speed for the engine power. In comparison to the Messerschmitt Bf 109 , the Yugoslav design had a shorter fuselage and smaller turning radius. It differed from British and German design concepts in that its proposed armament was concentrated in the fuselage. The designs were delivered to the VVKJ in time for approval by mid-1936, but
4563-592: A third engineer to help evaluate the design and determine the structural details. Slobodan Zrnić, the head of construction at the Yugoslav State Aircraft Factory in Kraljevo , was recruited, as he had worked as a specialist aircraft engineer in France. The project name for the IK-2 was changed from IK, standing for (Ljubomir) Ilić and Kosta (Sivčev), to IKZ, to include Zrnić. This name was changed, possibly due to
4732-535: A tight formation of three bombers; his aircraft received 56 hits from return fire, 20 of which were in the engine and propeller, but he managed to land the aircraft. The return of another IK-3 from the workshops meant that the number of serviceable IK-3s remained at three. It became difficult to continue activity from the 51st Fighter Group airfield at Zemun due to air attacks, so on 8 April the remaining IK-3s and Bf 109Es flew to an auxiliary airfield at Veliki Radinci , 50 km (31 mi) north-west of Belgrade, where
4901-399: A timid way tried to express the discontent that Croatian Republican Peasant Party mobilized) had been too tainted by their participation in government and was all but eliminated. The other gainers were the communists who had done especially well in the wider Macedonia region. The remainder of the seats were taken up by smaller parties that were at best skeptical of the centralizing platform of
5070-419: A total of 2,360 Spitfires and Seafires, more than 10% of total production. Henshaw wrote about flight testing Spitfires: After a thorough preflight check, I would take off, and once at circuit height, I would trim the aircraft and try to get her to fly straight and level with hands off the stick ... Once the trim was satisfactory, I would take the Spitfire up in a full-throttle climb at 2,850 rpm to
5239-457: A violent reaction from the governing majority including death threats. On 20 June 1928, a member of the government majority, the Serb deputy Puniša Račić , shot five members of the Croatian Peasant Party, including their leader Stjepan Radić, after Radić refused to apologize for earlier offense in which he accused Račić of stealing from civilian population. Two died on the floor of the Assembly while
Rogožarski IK-3 - Misplaced Pages Continue
5408-404: A warm climate, Yugoslavia was also relatively dry. Internal communications were poor, damage from World War I had been extensive, and with few exceptions agriculture was devoid of machinery or other modern farming technologies. Manufacturing was limited to Belgrade and the other major population centers, and consisted mainly of small, comparatively primitive facilities that produced strictly for
5577-552: A week, beginning 15 months after an order was placed. On 3 June 1936, the Air Ministry placed an order for 310 aircraft. Full-scale production of the Spitfire began at Supermarine's facility in Woolston, but the order clearly could not be completed in the 15 months promised. Supermarine was a small company, already busy building Walrus and Stranraer flying boats, and Vickers was busy building Wellington bombers. The initial solution
5746-409: A wing shape from an aircraft designed for an entirely different purpose." The elliptical wing was decided upon quite early on. Aerodynamically it was the best for our purpose because the induced drag caused in producing lift, was lowest when this shape was used: the ellipse was ... theoretically a perfection ... To reduce drag we wanted the lowest possible thickness-to-chord, consistent with
5915-448: Is compromise, and an improvement at one end of the performance envelope is rarely achieved without a deterioration somewhere else. When the last Spitfire rolled out in February 1948, a total of 20,351 examples of all variants had been built, including two-seat trainers , with some Spitfires remaining in service well into the 1950s. The Spitfire was the only British fighter aircraft to be in continuous production before, during, and after
6084-511: The Axis invasion of Yugoslavia began on 6 April 1941. All six were in service with the 51st Independent Fighter Group at Zemun near Belgrade . Pilots flying the IK-3 claimed 11 Axis aircraft had been shot down during the 11-day war. According to one account, to prevent them from falling into German hands, the surviving aircraft and incomplete airframes were destroyed by their crews and factory staff. Another account suggests that one aircraft survived
6253-482: The NACA 2200 series , which had been adapted to create a thickness-to-chord ratio of 13% at the root, reducing to 9.4% at the tip. A dihedral of 6° was adopted to give increased lateral stability. A wing feature that contributed greatly to its success was an innovative spar boom design, made up of five square tubes that fitted into each other. As the wing thinned out along its span, the tubes were progressively cut away in
6422-625: The Schneider Trophy seaplanes as a starting point. This led to the Type 300, with retractable undercarriage and a wingspan reduced by 6 ft (1.8 m). This design was submitted to the Air Ministry in July 1934, but was not accepted. It then went through a series of changes, including the incorporation of an enclosed cockpit, oxygen-breathing apparatus, smaller and thinner wings, and the newly developed, more powerful Rolls-Royce PV XII V-12 engine , which
6591-442: The Vidovdan Constitution in 1921 sparked tensions between the different Yugoslav ethnic groups . Trumbić opposed the 1921 constitution and over time grew increasingly hostile towards the Yugoslav government that he saw as being centralized in the favor of Serb hegemony over Yugoslavia. Three-quarters of the Yugoslav workforce was engaged in agriculture. A few commercial farmers existed, but most were subsistence peasants. Those in
6760-412: The aerodrome , and the installation of the most modern machine tools then available began two months after work started on the site. Although Morris Motors, under Lord Nuffield (an expert in mass motor-vehicle construction), managed and equipped the factory, it was funded by the government. By the beginning of 1939, the factory's original estimated cost of £2,000,000 had more than doubled, and even as
6929-658: The air force of the Axis puppet state, the Independent State of Croatia . The Germans had used a fence to separate the serviceable aircraft from other aircraft that had been earmarked for scrapping. In late June, while the German guards were distracted listening to news of the invasion of the Soviet Union , local communists, including former VVKJ mechanics, moved the fence. As a result, all the serviceable aircraft were scrapped, including
Rogožarski IK-3 - Misplaced Pages Continue
7098-408: The angle of incidence decreasing from +2° at its root to -½° at its tip. This caused the wing roots to stall before the tips, reducing tip-stall that could otherwise have resulted in a wing drop, often leading to a spin. As the wing roots started to stall, the separating air stream started to buffet (vibrate) the aircraft, warning the pilot, allowing even relatively inexperienced pilots to fly it to
7267-561: The shadow factory plan , to boost British aircraft production capacity under the leadership of Herbert Austin . He was given the task of building nine new factories, and to supplement the British car-manufacturing industry by either adding to overall capacity or increasing the potential for reorganisation to produce aircraft and their engines. In 1938, construction began on the Castle Bromwich Aircraft Factory (CBAF), next to
7436-463: The 162nd Fighter Squadron ( Kapetan Todor Gogić). The IK-3 was then tested against Yugoslav Messerschmitt Bf 109Es in mock dogfights. The evaluation concluded that the IK-3 had several advantages over the Bf 109E; in particular, the Yugoslav aircraft was more manoeuvrable in level flight, enabling it to quickly get behind a pursuing Bf 109E by making tight horizontal turns. In its first year of service, an IK-3
7605-489: The 51st Fighter Group was placed under the 6th Fighter Regiment , which was responsible for the defence of Belgrade. The 51st Fighter Group was further reinforced the day before the invasion began, with the 102nd Fighter Squadron equipped with Bf 109Es. When the invasion began on 6 April, the two IK-3 squadrons had only three serviceable aircraft each. The invasion commenced with a wave of 234 German dive bombers and medium bombers attacking Belgrade. Escorted by 120 fighters,
7774-456: The Air Ministry put forward a plan that its production be stopped after the initial order for 310, after which Supermarine would build Bristol Beaufighters . The managements of Supermarine and Vickers were able to convince the Air Ministry that production problems could be overcome, and a further order was placed for 200 Spitfires on 24 March 1938. The two orders covered the K, L, and N prefix serial numbers. The first production Spitfire came off
7943-583: The Air Ministry released specification F7/30 , calling for a modern fighter capable of a flying speed of 250 mph (400 km/h) to replace the Gloster Gauntlet biplane. R. J. Mitchell designed the Supermarine Type 224 to fill this role in competition with the Blackburn F.3 and Westland F.7/30 and privately funded designs from Gloster. The 224 was an open-cockpit monoplane with bulky gull wings and
8112-706: The Castle Bromwich plant to his ministry. Beaverbrook immediately sent in experienced management staff and workers from Supermarine, and gave control of the factory to Vickers-Armstrongs. Although resolving the problems took time, in June 1940, 10 Mk IIs were built; 23 rolled out in July, 37 in August, and 56 in September. By the time production ended at Castle Bromwich in June 1945, a total of 12,129 Spitfires (921 Mk IIs, 4,489 Mk Vs, 5,665 Mk IXs, and 1,054 Mk XVIs ) had been built, at
8281-546: The Croatian extreme nationalist Ustaše organisation. Because Aleksandar's eldest son, Peter II , was a minor, a regency council of three, specified in Aleksandar's will, took over the new king's royal powers and duties. The council was dominated by the 11-year-old king's first cousin once removed Prince Paul . Prince Paul decided to appoint well-known economist Milan Stojadinović as prime minister in 1935. His solution to solving
8450-508: The Croatian nationalist Ustaše, who were also angered by any settlement short of full independence for a Greater Croatia including all of Bosnia and Herzegovina. Fearing an invasion by the Axis powers , Yugoslavia signed the Tripartite Pact on 25 March 1941, pledging cooperation with the Axis. Massive anti-Axis demonstrations followed in Belgrade . On 27 March, the regime of Prince Paul
8619-541: The Democratic Party. The results left Nikola Pašić in a very strong position as the Democrats had no choice but to ally with the Radicals if they wanted to get their concept of a centralized Yugoslavia through. Pašić was always careful to keep open the option of a deal with the Croatian opposition. The Democrats and the Radicals were not quite strong enough to get the constitution through on their own and they made an alliance with
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#17330854320808788-557: The Democrats began to have doubts about the wisdom of his party's commitment to centralization and opened up negotiations with the opposition. This threatened to provoke a split in his party as his action was opposed by Svetozar Pribićević. It also gave Pašić a pretext to end the coalition. At first the King gave Pašić a mandate to form a coalition with Pribićević's Democrats. However, Pašić offered Pribićević too little for there to be much chance that Pribićević would agree. A purely Radical government
8957-535: The Goshawk led to the adoption of a cooling system which used 100% glycol . The radiators were housed in a new radiator-duct designed by Fredrick Meredith of the Royal Aircraft Establishment (RAE) at Farnborough, Hampshire . This used the cooling air to generate thrust , greatly reducing the net drag produced by the radiators. In turn, the leading-edge structure lost its function as a condenser, but it
9126-424: The IK-3 encouraged the three designers to pursue the idea of a twin-engined fighter, capable of long-range reconnaissance, photographic reconnaissance and operation as a "destroyer" or heavy fighter similar to the Messerschmitt Bf 110 . The concept included both one-seater and two-seater versions. Development of this new aircraft, designated IK-5, was commenced on the back of the success of the IK-3. The VVKJ ordered
9295-545: The King, and legislation could become law with the approval of one of the houses alone if also approved by the King. That same year, Croatian historian and anti-Yugoslavist intellectual Milan Šufflay was assassinated in Zagreb. As a response, Albert Einstein and Heinrich Mann sent an appeal to the International League of Human Rights in Paris condemning the murder, accusing the Yugoslav government. The letter states of
9464-721: The Kingdom of Montenegro. The creation of the state was supported by pan-Slavists and Yugoslav nationalists. For the pan-Slavic movement, all of the South Slav (Yugoslav) people had united into a single state. The creation was also supported by the Allies, who sought to break up the Austro-Hungarian Empire . The newly established Kingdom of Serbs, Croats and Slovenes participated in the Paris Peace Conference with Trumbić as
9633-600: The National Council of the State of Slovenes, Croats and Serbs appointed 28 members to start negotiation with the representatives of the government of the Kingdom of Serbia and Montenegro on creation of a new Yugoslav state, the delegation negotiated directly with regent Alexander Karađorđević . The negotiations would end, with the delegation of the National Council of the State of Slovenes, Croats and Serbs led by Ante Pavelić reading
9802-476: The Provisional Representation and the government. Because the Democratic Party led by Ljubomir Davidović pushed a highly centralized agenda a number of Croatian delegates moved into opposition. However, the radicals themselves were not happy that they had only three ministers to the Democratic Party's 11 and, on 16 August 1919, Protić handed in his resignation. Davidović then formed a coalition with
9971-596: The Radicals' main Serbian rivals, the Democrats. Stjepan Radić , the head of the Croatian Peasant Party, was imprisoned many times for political reasons. He was released in 1925 and returned to parliament. In the spring of 1928, Radić and Svetozar Pribićević waged a bitter parliamentary battle against the ratification of the Nettuno Convention with Italy. In this they mobilised nationalist opposition in Serbia but provoked
10140-463: The Rolls-Royce Merlin engine at £2,000, followed by the wings at £1,800 a pair, guns and undercarriage, both at £800 each, and the propeller at £350. In 1935, the Air Ministry approached Morris Motors Limited to ask how quickly their Cowley plant could be turned to aircraft production. In 1936, this informal request for major manufacturing facilities was replaced by a formal scheme, known as
10309-712: The Second World War. In the mid-1930s, aviation design teams worldwide began developing a new generation of fighter aircraft. The French Dewoitine D.520 and the German Messerschmitt Bf 109 , for example, were designed to take advantage of new techniques of monocoque construction, and the availability of new, high-powered, liquid-cooled, in-line aero engines. They also had refinements such as retractable undercarriages, fully enclosed cockpits, and low-drag, all-metal wings. These advances had been introduced on civil airliners years before, but were slow to be adopted by
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#173308543208010478-430: The Social Democrats. This government had a majority, but the quorum of the Provisional Representation was half plus one vote. The opposition then began to boycott the parliament. As the government could never guarantee that all of its supporters would turn up, it became impossible to hold a quorate meeting of the parliament. Davidović soon resigned, but as no one else could form a government he again became prime minister. As
10647-543: The Southampton area. To this end, the British government requisitioned the likes of Vincent's Garage in Station Square, Reading , which later specialised in manufacturing Spitfire fuselages, and Anna Valley Motors, Salisbury , which was to become the sole producer of the wing leading-edge fuel tanks for photo-reconnaissance Spitfires. A purpose-built works, specialising in manufacturing fuselages and installing engines,
10816-456: The Spitfire's development through many variants , from the Mk 1 to the Rolls-Royce Griffon-engined Mk 24, using several wing configurations and guns. The original airframe was designed to be powered by a Rolls-Royce Merlin engine producing 1,030 hp (768 kW). It was strong enough and adaptable enough to use increasingly powerful Merlins, and in later marks, Rolls-Royce Griffon engines producing up to 2,340 hp (1,745 kW). As
10985-430: The Spitfire's distinctive elliptical wing (designed by Beverley Shenstone ) with innovative sunken rivets to have the thinnest possible cross-section, achieving a potential top speed greater than that of several contemporary fighter aircraft, including the Hawker Hurricane . Mitchell continued to refine the design until his death in 1937, whereupon his colleague Joseph Smith took over as chief designer. Smith oversaw
11154-503: The UK over the North Sea , and Germany did not have any single-engine fighters with the range to accompany them. To carry out the mission of home defence, the design was intended to allow the Spitfire to climb quickly to intercept enemy bombers. The Spitfire's airframe was complex. The streamlined, semi-monocoque , duralumin-skinned fuselage had a number of compound curves built up over a skeleton of 19 formers , also known as frames. These started from frame number one, immediately behind
11323-501: The VVKJ or in the aeronautical industry. Ljubomir Ilić and Kosta Sivčev went through this program but, when they returned to Yugoslavia, both were employed in administrative work. Frustrated by this, they decided in 1931 to design a replacement for the Czechoslovakian -built Avia BH-33 E biplane fighter in service with the VVKJ. Working in a basement in Belgrade, and later in Ilić's apartment in Novi Sad , they secretly devoted their spare time to work on their design. They originally planned
11492-429: The Yugoslav Muslim Organization (JMO). The Muslim party sought and got concessions over the preservation of Bosnia in its borders and how the land reform would affect Muslim landowners in Bosnia. The Croatian Republican Peasant Party refused to swear allegiance to the King on the grounds that this presumed that Yugoslavia would be a monarchy, something that it contended only the Constituent Assembly could decide. The party
11661-402: The Yugoslav aeronautical industry which had resulted in a mixture of foreign and Yugoslav-made instruments being fitted to the aircraft. The Yugoslav Minister of War approved the acquisition of a further 48 IK-3s to be delivered in 1941–1942. The operational aircraft were allocated to the 51st Independent Fighter Group at Zemun, six each to the 161st Fighter Squadron ( Kapetan Savo Poljanec) and
11830-499: The Yugoslav people as a whole. The Radicals had done no better in that region but this presented them far less of a problem because they had campaigned openly as a Serbian party. The most dramatic gains had been made by the two anti-system parties. The Croatian Republican Peasant Party's leadership had been released from prison only as the election campaign began to get underway. According to Gligorijević, this had helped them more than active campaigning. The Croatian community (that had in
11999-478: The address in front of regent Alexander, who represented his father, King Peter I of Serbia , by which acceptance the kingdom was established. The name of the new Yugoslav state was Kingdom of Serbs, Croats and Slovenes ( Serbo-Croatian : Kraljevina Srba, Hrvata i Slovenaca / Краљевина Срба, Хрвата и Словенаца ; Slovene : Kraljevina Srbov, Hrvatov in Slovencev ) or its abbreviated form Kingdom of SCS ( Kraljevina SHS / Краљевина СХС ). The new kingdom
12168-581: The altered aerodynamics, culminating in those of the Mk 22/24 series, which were 25% larger in area than those of the Mk I. As the Spitfire gained more power and was able to manoeuvre at higher speeds, the possibility that pilots would encounter aileron reversal increased, and the Supermarine design team set about redesigning the wings to counter this. The original wing design had a theoretical aileron reversal speed of 580 mph (500 kn; 930 km/h), which
12337-423: The assembly line in mid-1938 and was flown by Jeffrey Quill on 15 May 1938, almost 24 months after the initial order. The final cost of the first 310 aircraft, after delays and increased programme costs, came to £1,870,242 or £1,533 more per aircraft than originally estimated. A production aircraft cost about £9,500. The most expensive components were the hand-fabricated and finished fuselage at roughly £2,500, then
12506-572: The beginning of a movement for women's suffrage appeared with the creation of the new state. The Social Democrats and the Slovenian People's Party supported women's suffrage but the Radicals opposed it. The Democratic Party was open to the idea but not committed enough to make an issue of it so the proposal fell. Proportional Representation was accepted in principle but the system chosen ( d'Hondt with very small constituencies) favored large parties and parties with strong regional support. The election
12675-450: The bending loads on the main-spar during landing. Ahead of the spar, the thick-skinned leading edge of the wing formed a strong and rigid, D-shaped box, which took most of the wing loads. At the time the wing was designed, this D-shaped leading edge was intended to house steam condensers for the evaporative cooling system intended for the PV-XII. Constant problems with the evaporative system in
12844-412: The best employment for it within the VVKJ, along with tactics to be used in Yugoslav conditions. These pilots observed that the controls were highly sensitive; the only real criticisms related to the visual distortion caused by the curved panels of the canopy . Some pilots believed that the fuselage-mounted armament should be supplemented by two wing-mounted machine guns. The test pilots also had to compare
13013-494: The bombers reached Belgrade at 07:00; they were met by the 51st Fighter Group, minus an IK-3 from the 161st Fighter Squadron that had developed engine trouble after takeoff and was unable to engage. The other five IK-3s were the first to meet the initial bomber wave but they were almost immediately attacked by Bf 109Es of Jagdgeschwader 77 . The pilots of the IK-3s claimed five German aircraft, and one aircraft from each Yugoslav squadron
13182-545: The borders at Postojna and Idrija were effectively undermined by the regent Alexander who preferred "good relations " with Italy. The Yugoslav kingdom bordered Italy and Austria to the northwest at the Rapallo border, Hungary and Romania to the north, Bulgaria to the east, Greece and Albania to the south, and the Adriatic Sea to the west. Almost immediately, it ran into disputes with most of its neighbours. Slovenia
13351-513: The borders of the new Kingdom of Serbs, Croats and Slovenes. Nevertheless, with the Treaty of Rapallo a population of half a million South Slavs, mostly Slovenes, were subjected to forced Italianization until the fall of Fascism in Italy . At the time when Benito Mussolini was willing to modify the Rapallo borders in order to annex the independent state of Rijeka to Italy , Pašić's attempts to correct
13520-602: The canopy to provide better visibility. The instrument layout was improved and the upper rear fuselage behind the pilot's seat was re-shaped. The folding undercarriage leg covers were replaced by single plates. The main changes were the replacement of the engine with a modified version of the Hispano-Suiza 12Y engine made under licence by the Czechoslovak company Avia and the replacement of the Hispano-Suiza HS.404 cannon by
13689-447: The company hangar at Zemun. The first six aircraft were delivered by late March 1940; delivery of the rest of the order was delayed until July due to delays by foreign suppliers. The first production aircraft was delivered to the VVKJ Test Group, where it was confirmed that the production aircraft were free of the faults in the prototype. The Test Group determined that the maximum speed, previously estimated at 540 km/h (340 mph),
13858-402: The company in the Southampton area. Quill devised the standard testing procedures, which with variations for specific aircraft designs operated from 1938. Alex Henshaw , chief test pilot at Castle Bromwich from 1940, was placed in charge of testing all Spitfires built at that factory. He co-ordinated a team of 25 pilots and assessed all Spitfire developments. Between 1940 and 1946, Henshaw flew
14027-452: The country's representative. Since the Allies had lured the Italians into the war with a promise of substantial territorial gains in exchange , which cut off a quarter of Slovene ethnic territory from the remaining three-quarters of Slovenes living in the Kingdom of SCS, Trumbić successfully vouched for the inclusion of most Slavs living in the former Austria-Hungary to be included within
14196-468: The country's three universities in Belgrade , Ljubljana , and Zagreb . Immediately after 1 December proclamation, negotiations between the National Council of Slovenes, Croats and Serbs and the Serbian government resulted in agreement over the new government which was to be headed by Nikola Pašić . However, when this agreement was submitted to the approval of the regent, Alexander Karađorđević, it
14365-567: The court. Pribićević later went into exile, whereas over the course of the 1930s Maček would become the leader of the entire opposition bloc. Immediately after the dictatorship was proclaimed, Croatian deputy Ante Pavelić left for exile from the country. The following years Pavelić worked to establish a revolutionary organization, the Ustaše , allied with the Internal Macedonian Revolutionary Organization (IMRO) against
14534-645: The creation of a united state of Serbs , Croats, and Slovenes to be led by the Serbian House of Karađorđević . In 1916, the Yugoslav Committee started negotiations with the Serbian Government in exile , on which they decided on the creation of the Kingdom of Yugoslavia, declaring the joint Corfu Declaration in 1917, the meetings were held at the Municipal Theatre of Corfu . In November 1918,
14703-402: The domestic market. The commercial potential of Yugoslavia's Adriatic ports went to waste because the nation lacked the capital or technical knowledge to operate a shipping industry. On the other hand, the mining industry was well developed due to the nation's abundance of mineral resources, but since it was primarily owned and operated by foreigners, most production was exported. Yugoslavia was
14872-527: The economic problems left over from the Great Depression was to make trade deals and get closer to Fascist Italy and Nazi Germany . The JRZ had majority support from Slovenes, Bosniaks, and Serbs. The only part missing was the support from Croats. This is why Milan Stojadinović called the JRZ regime a "Three-Legged Chair", Stojadinović wrote in his memoirs: "I called our party the three-legged chair, on which it
15041-476: The election of the Constituent Assembly, a Provisional Representation served as a parliament which was formed by delegates from the various elected bodies that had existed before the creation of the state. A realignment of parties combining several members of the Serbian opposition with political parties from the former Austria-Hungary led to the creation of a new party, The Democratic Party, that dominated
15210-405: The end of each main wing assembly. When the Spitfire took on a role as a high-altitude fighter (Marks VI and VII and some early Mk VIIIs), the standard wing tips were replaced by extended, "pointed" tips which increased the wingspan from 36 ft 10 in (11.23 m) to 40 ft 2 in (12.24 m). The other wing-tip variation, used by several Spitfire variants, was the "clipped" wing;
15379-513: The fabric covering of the ailerons "ballooned" at high speeds, adversely affecting the aerodynamics. Replacing the fabric covering with light alloy dramatically improved the ailerons at high speed. During the Battle of Britain, pilots found the Spitfire's ailerons were far too heavy at high speeds, severely restricting lateral manoeuvres such as rolls and high-speed turns, which were still a feature of air-to-air combat. The Spitfire had detachable wing tips which were secured by two mounting points at
15548-567: The final approach and for landing, and the pilot was to retract them before taxiing. The ellipse also served as the design basis for the Spitfire's fin and tailplane assembly, once again exploiting the shape's favourable aerodynamic characteristics. Both the elevators and rudder were shaped so that their centre of mass was shifted forward, reducing control-surface flutter. The longer noses and greater propeller-wash resulting from larger engines in later models necessitated increasingly larger vertical, and later, horizontal tail surfaces to compensate for
15717-434: The first Spitfires were being built in June 1940, the factory was still incomplete, and suffering from personnel problems. The Spitfire's stressed-skin construction required precision engineering skills and techniques that were beyond the capabilities of the local labour force, and some time was required to retrain them. Difficulties arose with management, who ignored Supermarine's tooling and drawings in favour of their own, and
15886-469: The focal points for these workshops: Southampton's Eastleigh Airport; Salisbury and the High Post and Chattis Hill aerodromes; Trowbridge and RAF Keevil ; and Reading's Henley and Aldermaston aerodromes. Completed Spitfires were delivered to the airfields on Commer " Queen Mary " low-loader trailers, there to be fully assembled, tested, then passed on to the RAF. An experimental factory at Newbury
16055-534: The following day all remaining aircraft of the 6th Fighter Regiment, including the remaining IK-3s, were burned by their crews. According to aviation writers Dragan Savić and Boris Ciglić, one serviceable IK-3 was captured by the Germans in April 1941 and it was joined by another by the end of June. Both aircraft were located at Zemun, along with 23 other former VVKJ aircraft in working condition that were destined for service with
16224-428: The four main fuselage longerons to the rest of the airframe. Behind the bulkhead were five U-shaped half-frames which accommodated the fuel tanks and cockpit. The rear fuselage started at the 11th frame, to which the pilot's seat and (later) armour plating were attached, and ended at the 19th, which was mounted at a slight forward angle just forward of the fin. Each of these nine frames was oval, reducing in size towards
16393-493: The fuel tankage dropped to 75 gallons from 94. On 5 March 1936, the prototype ( K5054 ) , fitted with a fine-pitch propeller to give more power for takeoff, took off on its first flight from Eastleigh Aerodrome (later Southampton Airport). At the controls was Captain Joseph "Mutt" Summers , chief test pilot for Vickers, who is quoted as saying, "don't touch anything" on landing. This eight-minute flight came four months after
16562-477: The fuselage, wings, and tailplane was secured by dome-headed rivets, and in critical areas such as the wing forward of the main spar where an uninterrupted airflow was required, with flush rivets. From February 1943 flush riveting was used on the fuselage, affecting all Spitfire variants. In some areas, such as at the rear of the wing and the lower tailplane skins, the top was riveted and the bottom fixed by brass screws which tapped into strips of spruce bolted to
16731-425: The goal of reaching an agreement with the Croatian opposition. Accordingly, on 26 August 1939, Vladko Maček became vice premier of Yugoslavia and an autonomous Banovina of Croatia was established with its own parliament. These changes satisfied neither Serbs, who were concerned with the status of the Serb minority in the new Banovina of Croatia and who wanted more of Bosnia and Herzegovina as Serbian territory, nor
16900-415: The government and of minister Svetozar Pribićević in particular. One of the few laws successfully passed by the Provisional Representation was the electoral law for the constituent assembly. During the negotiations that preceded the foundation of the new state, it had been agreed that voting would be secret and based on universal suffrage. It had not occurred to them that universal might include women until
17069-489: The internal divisions from the 33 oblasts to nine new banovinas on 3 October. This decision was made following a proposal by the British ambassador to better decentralize the country, modeled on Czechoslovakia . A Court for the Protection of the State was soon established to act as the new regime's tool for putting down any dissent. Opposition politicians Vladko Maček and Svetozar Pribićević were arrested under charges by
17238-610: The invasion and was later destroyed by sabotage . The IK-3 design was the basis for the post-war Yugoslav-built Ikarus S-49 fighter. In the late 1920s, the Royal Yugoslav Air Force ( Serbian : Vazduhoplovstvo vojske Kraljevine Jugoslavije , VVKJ) and the Royal Aero Club of Yugoslavia helped send aspiring aeronautical engineers to France to gain knowledge. It was intended that after this advanced training, they would return to Yugoslavia and be offered specialist roles in
17407-632: The later marks, although they were faster than the earlier ones, were also much heavier, so did not handle so well. You did not have such positive control over them. One test of manoeuvrability was to throw her into a flick-roll and see how many times she rolled. With the Mark II or the Mark V one got two-and-a-half flick-rolls, but the Mark IX was heavier and you got only one-and-a-half. With the later and still heavier versions, one got even less. The essence of aircraft design
17576-543: The lead of its neighbors in allowing itself to become a dependent of Nazi Germany . Although Yugoslavia had enacted a compulsory public education policy, it was inaccessible to many peasants in the countryside. Official literacy figures for the population stood at 50%, but it varied widely throughout the country. Less than 10% of Slovenes were illiterate, whereas over 80% of Macedonians and Bosnians could not read or write. Approximately 10% of initial elementary school students went on to attend higher forms of education, at one of
17745-582: The legitimate government. This was established on 2 November following the signing of the Treaty of Vis by Ivan Šubašić (on behalf of the Kingdom) and Josip Broz Tito (on behalf of the Yugoslav Partisans ). Following the assassination of Archduke Franz Ferdinand of Austria by the Bosnian Serb Gavrilo Princip and the outbreak of World War I , Serbia was invaded and occupied by
17914-465: The life of Radić hung in the balance. The opposition now completely withdrew from parliament, declaring that they would not return to a parliament in which several of their representatives had been killed, and insisting on new elections. On 1 August, at a meeting in Zagreb, they renounced 1 December Declaration of 1920. They demanded that the negotiations for unification should begin from scratch. On 8 August Stjepan Radić died. On 6 January 1929, using as
18083-571: The limits of its performance. This washout was first featured in the wing of the Type 224, and became a consistent feature in subsequent designs leading to the Spitfire. The complex wing design, especially the precision required to manufacture the vital spar and leading-edge structures, caused some major delays in the production of the Spitfire at first. The problems increased when the work was put out to subcontractors, most of whom had never dealt with metal-structured, high-speed aircraft. By June 1939, most of these problems had been resolved, and production
18252-466: The lower ribs. The removable wing tips were made up of duralumin-skinned spruce formers. At first, the ailerons, elevators, and rudder were fabric-covered, but once combat experience showed that fabric-covered ailerons were impossible to use at high speeds a light alloy replaced the fabric, enhancing control throughout the speed range. In 1934, Mitchell and the design staff decided to use a semi-elliptical wing shape to solve two conflicting requirements;
18421-451: The maiden flight of the contemporary Hurricane. K5054 was fitted with a new propeller, and Summers flew the aircraft on 10 March 1936; during this flight, the undercarriage was retracted for the first time. After the fourth flight, a new engine was fitted, and Summers left the test flying to his assistants, Jeffrey Quill and George Pickering. They soon discovered that the Spitfire was a very capable aircraft, but not perfect. The rudder
18590-416: The main factor had been the pilot's handling of the highly sensitive controls. The loss of the prototype and some changes in the construction of the production model delayed the fulfilment of the contract. Further tests were conducted on the wing and it was found to withstand a g-force of 14. Modifications were made for the production model, including the use of flat plexiglass panels in the windscreen and
18759-527: The main spar, preventing the wings from twisting. Mitchell has sometimes been accused of copying the wing shape of the Günter brothers -designed Heinkel He 70 , which first flew in 1932, but as Beverley Shenstone , the aerodynamicist on Mitchell's team, explained: "Our wing was much thinner and had quite a different section to that of the Heinkel. In any case, it would have been simply asking for trouble to have copied
18928-410: The market for them to collapse as global demand contracted heavily and the situation for export-oriented farmers further deteriorated when nations everywhere started to erect trade barriers. Italy was a major trading partner of Yugoslavia in the initial years after World War I, but ties fell off after Benito Mussolini came to power in 1922. In the grim economic situation of the 1930s, Yugoslavia followed
19097-457: The military, who favoured the biplane's simplicity and manoeuvrability. Mitchell's design aims were to create a well-balanced, high-performance fighter aircraft capable of fully exploiting the power of the Merlin engine, while being relatively easy to fly. At the time, with France as an ally , and Germany thought to be the most likely future opponent, no enemy fighters were expected to appear over Great Britain. German bombers would have to fly to
19266-403: The necessary strength. But near the root the wing had to be thick enough to accommodate the retracted undercarriages and the guns ... Mitchell was an intensely practical man ... The ellipse was simply the shape that allowed us the thinnest possible wing with room inside to carry the necessary structure and the things we wanted to cram in. And it looked nice. The wing section used was from
19435-513: The need for radical land reform. A disagreement over electoral law finally led the Democratic Party to vote against the government in Parliament and the government was defeated. Though this meeting had not been quorate, Vesnić used this as a pretext to resign. His resignation had the intended effect: the Radical Party agreed to accept the need for centralization, and the Democratic Party agreed to drop its insistence on land reform. Vesnić again headed
19604-542: The new Croatian Peasant Party leader Vladko Maček. Despite these measures, opposition to the dictatorship continued, with Croats calling for a solution to what was called the "Croatian question". On 9 October 1934, the king was assassinated in Marseille , France, by Bulgarian Veličko Kerin (also known by his revolutionary pseudonym Vlado Chernozemski ), an activist of IMRO, in a conspiracy with Yugoslav exiles and radical members of banned political parties in cooperation with
19773-464: The new government. The Croatian Community and the Slovenian People's Party were however not happy with the Radicals' acceptance of centralization. Neither was Stojan Protić, and he withdrew from the government on this issue. In September 1920 a peasant revolt broke out in Croatia, the immediate cause of which was the branding of the peasants' cattle. The Croatian community blamed the centralizing policies of
19942-547: The new wing could give an increase in speed of 55 mph (48 kn; 89 km/h) over the Spitfire Mk 21. The new wing was initially fitted to a Spitfire Mk XIV. Later, a new fuselage was designed, with the new fighter becoming the Supermarine Spiteful . The Rolls Royce engine's designers deliberately chose a carburettor for the Merlin engine: Sir Stanley Hooker explained in his autobiography that "the Germans paid
20111-439: The next month, other raids were mounted, until, on 26 September 1940, both factories were destroyed, with 92 people killed and a large number injured. Most of the casualties were experienced aircraft-production workers. Fortunately for the future of the Spitfire, many of the production jigs and machine tools had already been relocated by 20 September, and steps were being taken to disperse production to small facilities throughout
20280-510: The opposition continued their boycott, the government decided it had no alternative but to rule by decree. This was denounced by the opposition who began to style themselves as the Parliamentary Community. Davidović realized that the situation was untenable and asked the King to hold immediate elections for the Constituent Assembly. When the King refused, he felt he had no alternative but to resign. The Parliamentary Community now formed
20449-512: The performance of the IK-3 with the Hawker Fury (a biplane), Heinkel He 112 , Morane-Saulnier M.S. 405 and Hawker Hurricane. They concluded that the IK-3 most closely matched the Morane-Saulnier; the Yugoslav aircraft was 40 km/h (25 mph) faster. In November 1938, the VVKJ placed an order with Rogožarski for 12 aircraft. On 19 January 1939, test pilot Kapetan Milan Pokorni put
20618-399: The propeller unit, to the tail unit attachment frame. The first four frames supported the glycol header tank and engine cowlings. Frame five, to which the engine bearers were secured, supported the weight of the engine and its accessories. This was a strengthened double frame which also incorporated the fireproof bulkhead, and in later versions of the Spitfire, the oil tank. This frame also tied
20787-510: The prototype for the RAF. He had been given orders to fly the aircraft and then to make his report to the Air Ministry on landing. Edwardes-Jones' report was positive; his only request was that the Spitfire be equipped with an undercarriage position indicator. A week later, on 3 June 1936, the Air Ministry placed an order for 310 Spitfires, at a cost of £ 1,395,000. before the A&;AEE had issued any formal report. Interim reports were later issued on
20956-431: The prototype into a steep dive. When he reached 400 m (1,300 ft), the windscreen detached from the aircraft; Pokorni pulled up hard and the strain broke off half of the starboard wing. The aircraft crashed, and Pokorni was killed. An inquiry determined that modifications to the windscreen had contributed to the accident. Engineers recalculated the stress factors on the airframe and they were found to be safe, and
21125-404: The radiator under the starboard wing was halved in size and the intercooler radiator housed alongside. Under the port wing, a new radiator fairing housed a square oil cooler alongside of the other half-radiator unit. The two radiator flaps were now operated automatically by a thermostat . Another wing feature was its washout . The trailing edge of the wing twisted slightly upward along its span,
21294-432: The rated altitude of one or both supercharger blowers. Then I would make a careful check of the power output from the engine, calibrated for height and temperature ... If all appeared satisfactory, I would then put her into a dive at full power and 3,000 rpm, and trim her to fly hands and feet off at 460 mph (740 km/h) IAS (Indicated Air Speed). Personally, I never cleared a Spitfire unless I had carried out
21463-458: The remaining IK-3s were scrambled with the rest of the 51st Fighter Group but the IK-3 pilots claimed no victories. A joint claim was made during the third German attack at 14:00, a twin-engined bomber by Gogić and another pilot from the 162nd Fighter Squadron. The following day, the IK-3 pilots made five or six sorties against German bomber formations and their fighter escorts, and claimed three bombers between them. At 17:00, Milislav Semiz attacked
21632-528: The same time removing bomb carry requirement and reducing fuel capacity. Mitchell foresaw no problem adding the guns and welcomed the reduction which would reduce weight. A specification for an eight gun fighter, F5/34 had come from a recommendation by Squadron Leader Ralph Sorley of the Operational Requirements section at the Air Ministry. In the redesign the change was made from Vickers machine guns to .303 in (7.7 mm) Brownings) , and
21801-667: The same year, prior to the country being invaded by the Axis powers . In April 1941, the country was occupied and partitioned by the Axis powers . A royal government-in-exile , recognized by the United Kingdom and, later, by all the Allies , was established in London . In 1944, after pressure from the British Prime Minister Winston Churchill , the King recognized the government of Democratic Federal Yugoslavia as
21970-533: The same year, the Kingdom of Montenegro also proclaimed its unification with Serbia, whereas the regions of Kosovo and Vardar Macedonia had become parts of Serbia prior to the unification. The state was ruled by the Serbian dynasty of Karađorđević , which previously ruled the Kingdom of Serbia under Peter I from 1903 (after the May Coup ) onward. Peter I became the first king of Yugoslavia until his death in 1921. He
22139-535: The similarities between the Cyrillic " З " (Z) and the Arabic numeral "3", and the aircraft became known as the IK-3. The aircraft was to be powered by a Hispano-Suiza 12Y 29 engine, generating 980 hp (730 kW) at an altitude of 5,000 m (16,000 ft). The designers favoured manoeuvrability over speed, trying to find a compromise between the German and British concepts of a modern monoplane fighter. The design had
22308-460: The south were especially poor, living in a hilly, infertile region. No large estates existed except in the north, and all of those were owned by foreigners. Indeed, one of the first actions undertaken by the new Yugoslav state in 1919 was to break up the estates and dispose of foreign, and in particular Hungarian landowners. Nearly 40% of the rural population was surplus (i.e., excess people not needed to maintain current production levels), and despite
22477-488: The standard wing tips were replaced by wooden fairings which reduced the span by 3 ft 6 in (1.07 m). The wing tips used spruce formers for most of the internal structure with a light alloy skin attached using brass screws. The light alloy split flaps at the trailing edge of the wing were also pneumatically operated via a finger lever on the instrument panel. Only two positions were available; fully up or fully down (85°). Flaps were normally lowered only during
22646-400: The state. In 1931, Alexander decreed a new Constitution which made executive power the gift of the King. Elections were to be by universal male suffrage. The provision for a secret ballot was dropped, and pressure on public employees to vote for the governing party was to be a feature of all elections held under Alexander's constitution. Further, half the upper house was directly appointed by
22815-408: The surviving aircraft of the 6th Fighter Regiment were concentrated. Poor weather made operations impossible until 11 April, when Semiz shot down a Bf 110 that had strafed the airfield. Later that day, Gogić and another IK-3 pilot claimed one Junkers Ju 87 'Stuka' dive bomber each during a patrol. That night, German troops approached within 15 km (9.3 mi) of the airfield at Veliki Radinci and
22984-430: The tail, and incorporated several lightening holes to reduce their weight as much as possible without weakening them. The U-shaped frame 20 was the last frame of the fuselage proper and the frame to which the tail unit was attached. Frames 21, 22 and 23 formed the fin; frame 22 incorporated the tailwheel opening and frame 23 was the rudder post. Before being attached to the main fuselage, the tail unit frames were held in
23153-452: The theoretical aileron reversal speed was increased to 825 mph (717 kn; 1,328 km/h). Alongside the redesigned wing, Supermarine also experimented with the original wing, raising the leading edge by 1 inch (25 mm), with the hope of improving pilot view and reducing drag. This wing was tested on a modified F Mk 21, also called the F Mk 23, (sometimes referred to as "Valiant" rather than "Spitfire"). The increase in performance
23322-768: The third least industrialized nation in Eastern Europe after Bulgaria and Albania . Yugoslavia was typical of Eastern European nations in that it borrowed large sums of money from the West during the 1920s. When the Great Depression began in 1929, the Western lenders called in their debts, which could not be paid back. Some of the money was lost to graft, although most was used by farmers to improve production and export potential. Agricultural exports, however, were always an unstable prospect as their export earnings were heavily reliant on volatile world market prices. The Great Depression caused
23491-419: The time of the Axis invasion, and the only prototype to be fitted with a non-production engine was deliberately destroyed by factory personnel during the invasion, along with the incomplete production aircraft. Development of a dual-control two-seat trainer variant of the IK-3 had commenced but pressure on the design team had delayed the completion of the project when the invasion intervened. The development of
23660-581: The two IK-3s. "The IK-3s put up a valiant resistance against the Luftwaffe," wrote William Green , "scoring a number of 'kills' before they were finally destroyed in combat." Aviation writers Šime Oštrić and Čedomir Janić credit the IK-3 pilots with 11 victories, Semiz being the most successful, with four victories. Data from Oštrić & Janić General characteristics Performance Armament Related development Aircraft of comparable role, configuration, and era Related lists Kingdom of Yugoslavia The Kingdom of Yugoslavia
23829-405: The wing needed to be thin to avoid creating too much drag , but it had to be thick enough to house the retractable undercarriage, armament, and ammunition. An elliptical planform is the most efficient aerodynamic shape for an untwisted wing, leading to the lowest amount of induced drag . The ellipse was skewed so that the centre of pressure, which occurs at the quarter- chord position, aligned with
23998-402: The workforce continually threatened strikes or "slow downs" until their demands for higher wages were met. In spite of promises that the factory would be producing 60 per week starting in April, by May 1940, Castle Bromwich had not yet built its first Spitfire. On 17 May, Minister of Aircraft Production Lord Beaverbrook telephoned Lord Nuffield and manoeuvred him into handing over control of
24167-540: Was 527 km/h (327 mph), at an altitude of 5,400 m (17,700 ft). By July 1940, a further series of 25 IK-3s had commenced construction at the Rogožarski factory. A shortage of engines was a major obstacle to mass production and development of the IK-3, so tests were conducted with more powerful engines, including the Daimler-Benz DB 601 , Rolls-Royce Merlin II and Hispano-Suiza 12Y51. The tests were incomplete at
24336-544: Was a country in Southeast and Central Europe that existed from 1918 until 1941. From 1918 to 1929, it was officially called the Kingdom of Serbs, Croats, and Slovenes , but the term " Yugoslavia " ( lit. ' Land of the South Slavs ' ) was its colloquial name due to its origins. The official name of the state was changed to "Kingdom of Yugoslavia" by King Alexander I on 3 October 1929. The preliminary kingdom
24505-461: Was built at Star Road, Caversham in Reading. The drawing office in which all Spitfire designs were drafted was moved to Hursley Park , near Winchester . This site also had an aircraft assembly hangar where many prototype and experimental Spitfires were assembled, but since it had no associated aerodrome, no Spitfires ever flew from Hursley. Four towns and their satellite airfields were chosen to be
24674-566: Was difficult to determine, since it had been an integral part of Austria for 400 years. The Vojvodina region was disputed with Hungary, Macedonia with Bulgaria, Rijeka with Italy. A plebiscite was also held in the Province of Carinthia , which opted to remain in Austria. Austrians had formed a majority in this region although numbers reflected that some Slovenes did vote for Carinthia to become part of Austria. The Dalmatian port city of Zadar and
24843-461: Was formed in 1918 by the merger of the provisional State of Slovenes, Croats and Serbs (itself formed from territories of the former Austria-Hungary , encompassing today's Bosnia and Herzegovina and most of today's Croatia and Slovenia ) and Banat, Bačka and Baranja (that had been part of the Kingdom of Hungary within Austria-Hungary) with the formerly independent Kingdom of Serbia . In
25012-473: Was formed with a mandate to hold elections. The Radicals made gains at the expense of the Democrats but elsewhere there were gains by Radić's Peasant's Party. Serb politicians around Radic regarded Serbia as the standard bearer of Yugoslav unity, as the state of Piedmont had been for Italy, or Prussia for the German Empire ; a kind of " Greater Serbia ". Over the following years, Croatian resistance against
25181-402: Was held on 28 November 1920. When the votes were counted the Democratic Party had won the most seats, more than the Radicals – but only just. For a party that had been so dominant in the Provisional Representation, that amounted to a defeat. Further it had done rather badly in all former Austria-Hungarian areas. That undercut the party's belief that its centralization policy represented the will of
25350-519: Was later adapted to house integral fuel tanks of various sizes — a feature patented by Vickers-Supermarine in 1938. The airflow through the main radiator was controlled by pneumatic exit flaps. In early marks of the Spitfire (Mk I to Mk VI), the single flap was operated manually using a lever to the left of the pilot's seat. When the two-stage Merlin was introduced in the Spitfire Mk IX , the radiators were split to make room for an intercooler radiator;
25519-497: Was later named the "Merlin". In November 1934, Mitchell, with the backing of Supermarine's owner Vickers-Armstrong , started detailed design work on this refined version of the Type 300. On 1 December 1934, the Air Ministry issued contract AM 361140/34, providing £10,000 for the construction of Mitchell's improved Type 300 design. In April 1935 Ralph Sorley spoke to Mitchell about the new specification F10/35 which called for armament of at least six and preferably eight guns while at
25688-516: Was lost when one of the squadron commanders, Kapetan Anton Ercigoj, was making a mock attack on a Potez 25 over the confluence of the Sava and Danube rivers. After passing below the Potez, he went into a climb with the intention of performing a loop. His rate of climb was too steep and the aircraft fell into a spin at low altitude and hit the water. Before the Axis invasion of Yugoslavia in early April 1941,
25857-434: Was lost. Poljanec had claimed a twin-engined bomber and a Bf 109E; when he returned to Zemun in his badly damaged aircraft, he was strafed by a Messerschmitt Bf 110, which further damaged his aircraft and wounded him. After this encounter, only three IK-3s were serviceable, including the one that had developed engine difficulties prior to the first German wave. A second wave of German aircraft arrived over Belgrade at 10:00 and
26026-401: Was made up of the formerly independent kingdoms of Serbia and Montenegro ( Montenegro having been absorbed into Serbia the previous month ), and of a substantial amount of territory that was formerly part of Austria-Hungary, the State of Slovenes, Croats and Serbs. The main states which formed the new Kingdom were the State of Slovenes, Croats and Serbs; Vojvodina ; and the Kingdom of Serbia with
26195-533: Was minimal and this experiment was abandoned. Supermarine developed a new laminar-flow wing based on new aerofoil profiles developed by the National Advisory Committee for Aeronautics in the United States, with the objective of reducing drag and improving performance. These laminar-flow airfoils were the Supermarine 371-I used at the root and the 371-II used at the tip. Supermarine estimated that
26364-484: Was no longer held up by a lack of wings. All the main flight controls were originally metal structures with fabric covering. Designers and pilots felt that having ailerons which required a degree of effort to move at high speed would avoid unintended aileron reversal, throwing the aircraft around and potentially pulling the wings off. Air combat was also felt to take place at relatively low speeds and high-speed manoeuvring would be physically impossible. Flight tests showed
26533-585: Was not in any real position to help. Regardless of this, on 6 April 1941, the Axis powers launched the invasion of Yugoslavia and quickly conquered it. The royal family, including Prince Paul, escaped abroad and were kept under house arrest in British Kenya . Supermarine Spitfire The Supermarine Spitfire is a British single-seat fighter aircraft used by the Royal Air Force and other Allied countries before, during, and after World War II . It
26702-574: Was oversensitive, and the top speed was just 330 mph (528 km/h), little faster than Sydney Camm 's new Merlin-powered Hurricane. A new and better-shaped, two-bladed, wooden propeller allowed the Spitfire to reach 348 mph (557 km/h) in level flight in mid-May, when Summers flew K5054 to RAF Martlesham Heath and handed the aircraft over to Squadron Leader Anderson of the Aeroplane & Armament Experimental Establishment (A&AEE). Here, Flight Lieutenant Humphrey Edwardes-Jones took over
26871-472: Was overthrown by a military coup d'état with British support. The 17-year-old Peter II was declared to be of age and placed in power. General Dušan Simović became his Prime Minister. Yugoslavia withdrew its support for the Axis de facto without formally renouncing the Tripartite Pact. Although the new rulers opposed Nazi Germany , they also feared that if Germany attacked Yugoslavia, the United Kingdom
27040-725: Was possible to sit when necessary, although a chair with four legs is far more stable" - the fourth leg being the Croats, whose support was mostly behind the HSS. Prince Paul did not like this at first, but let him continue as long as it fixed the economy. Paul was concerned with rising tensions in Europe, especially with the Anschluss and the Munich Agreement Therefore, Paul ousted Milan Stojadinović replacing him with Dragiša Cvetković for being
27209-419: Was rejected, producing the new state's first governmental crisis. Many regarded this rejection as a violation of parliamentary principles, but the matter was resolved when the regent suggested replacing Pašić with Stojan Protić , a leading member of Pašić's Radical Party. The National Council and the Serbian government agreed and the new government came into existence on 20 December 1918. In this period before
27378-451: Was somewhat lower than that of some contemporary fighters. The Royal Aircraft Establishment noted that, at 400 mph (350 kn; 640 km/h) indicated airspeed , roughly 65% of aileron effectiveness was lost due to wing twist. The new wing of the Spitfire F Mk 21 and its successors was designed to help alleviate this problem. Its stiffness was increased by 47%, and a new aileron design using piano hinges and geared trim tabs meant
27547-605: Was succeeded by his son Alexander I , who had been regent for his father. He was known as "Alexander the Unifier" and he renamed the kingdom "Yugoslavia" in 1929. He was assassinated in Marseille by Vlado Chernozemski , a member of the Internal Macedonian Revolutionary Organization (IMRO), during his visit to France in 1934. The crown passed to his 11-year-old son, Peter . Alexander's cousin Paul ruled as Prince regent until 1941, when Peter II came of age. The royal family flew to London
27716-463: Was the only British fighter produced continuously throughout the war. The Spitfire remains popular among enthusiasts. Around 70 remain airworthy , and many more are static exhibits in aviation museums throughout the world. The Spitfire was designed as a short-range, high-performance interceptor aircraft by R. J. Mitchell , chief designer at Supermarine Aviation Works, which operated as a subsidiary of Vickers-Armstrong from 1928. Mitchell developed
27885-445: Was the subject of a Luftwaffe daylight raid, but the bombs missed their target and hit a nearby school. All production aircraft were flight tested before delivery. During the Second World War, Jeffrey Quill was Vickers Supermarine's chief test pilot, in charge of flight testing all aircraft types built by Vickers Supermarine. He oversaw a group of 10 to 12 pilots responsible for testing all developmental and production Spitfires built by
28054-419: Was to subcontract the work. Although outside contractors were supposed to be involved in manufacturing many important Spitfire components, especially the wings, Vickers-Armstrongs (the parent company) was reluctant to see the Spitfire being manufactured by outside concerns, and was slow to release the necessary blueprints and subcomponents. As a result of the delays in getting the Spitfire into full production,
28223-491: Was unable to muster a quorum. Hence the Parliamentary Community, now in government, was forced to rule by decree. For the Parliamentary Community to thus violate the basic principle around which they had formed put them in an extremely difficult position. In April 1920, widespread worker unrest and a railway strike broke out. According to Gligorijević, this put pressure on the two main parties to settle their differences. After successful negotiations, Protić resigned to make way for
28392-458: Was unable to take its seats. Most of the opposition though initially taking their seats declared boycotts as time went so that there were few votes against. However, the constitution decided against 1918 agreement between the State of Slovenes, Croats and Serbs and the Kingdom of Serbia , which stated that a 66% majority that 50% plus one vote would be needed to pass, irrespective of how many voted against. Only last minute concessions to Džemijet ,
28561-520: Was used in the European , Mediterranean , Pacific , and South-East Asian theatres. Much loved by its pilots, the Spitfire operated in several roles, including interceptor, photo-reconnaissance, fighter-bomber, and trainer, and it continued to do so until the 1950s. The Seafire was an aircraft carrier–based adaptation of the Spitfire, used in the Fleet Air Arm from 1942 until the mid-1950s. In 1931,
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