Frustated Projects

Great stuff here!

The Arado Ar 240 design was carefully planned. World War 2 was a time when technological advancements and improvements especially in the war machinery were made. War machineries such as airplanes needed to be upgraded and improved regularly to have the upper hand in the war. Such an upgrade was done in 1938, when the RLM or the German War Ministry decided to replace the already obsolete Messerschmitt BF 110 Zerstorer, which was a two-man crew, twin engine heavy fighter. In response to this needed change, two aircraft firms namely; the Arado Aircraft Firm and the Messerschmitt Aircraft Firm – decided to take on the task. Since the Messerschmitt Firm has more experienced in the manufacturing of the heavy fighter aircrafts, their new design was accepted and the new Messerschmitt Me 210 was immediately launched into service during the war. The design created by the Arado firm was considered to be more complicated however since it showed exceptional performance and capabilities, the RLM decided to order prototypes for the design which was to be known as the Arado Ar 240.

The Arado Ar 240 was a WW2 German aircraft that followed the traditional design of a twin-engine plane which has the capability of becoming a good heavy fighter and an excellent dive bomber plane because of the introduction of a dive braking system. The engines of this WW2 aircraft were located away from the fuselage and in the middle of the monoplane wing assembly. The Ar 240 can accommodate a two-man crew (pilot and navigator/gunner) inside a fully-pressurized cockpit. The Ar 240's armaments included two barbettes (containing 2x7.92mm MG81 machine guns) which were attached to the fuselage and were controlled remotely by the navigator-gunner. Another two 7.92mm MG17 machine guns were also installed in a fixed position which can be controlled by the pilot. This WW2 German aircraft can also carry a total bomb-load of 3,968 pounds. The first Ar 240 prototype first became airborne in 1940. There were a total of 14 planes of this designed produced during the war.

The Seversky XP-41 was a fighter aircraft built in the United States in 1939. A single prototype was modified from the last production Seversky P-35 by adding a new streamlined canopy, a Wright R-1830-19 engine with a two-speed supercharger, and revised landing gear. XP-41 first flew in March 1939. The aircraft was developed in parallel with the P-43 Lancer, and work was stopped when the USAAC showed a preference for the latter.

The Wibault system of metal airframe construction, with which Vickers had gained experience in building the Type 121 Wibault Scout, was utilised for a low-powered shipboard fighter to Specification 17/25. Submitted to the Air Ministry on 15 December 1925, this type, to be named Vireo, was awarded a one-aircraft contract. Intended to use either wheel or float undercarriage, and suitable for launching from a catapult, the Vireo was powered by a 230hp supercharged Armstrong Siddeley Lynx IV seven-cylinder radial air-cooled engine and had provision for two wing-mounted 7.7mm machine guns firing outside the propeller disc. The structural design of the Vireo followed closely that of the Type 121, with the airframe virtually entirely covered by corrugated metal skinning. Flown early in March 1928 - flight testing having been delayed by extensive aerodynamic and structural tests undertaken at the Royal Aircraft Establishment - the Vireo was evaluated at Martlesham Heath in April and deck trials then took place aboard HMS Furious on 12 July. The Vireo was fitted with a twin-float undercarriage, but, in the event, seaplane trials that were to have taken place at the MAEE, Felixstowe, were not proceeded with. The speed performance of the Vireo was inevitably poor owing to the combination of low engine power and high drag resulting from the corrugated surfaces, and it suffered extremely unpleasant stalling characteristics. In consequence, development was terminated.

The all metal Letov Š 50 was designed to a specification for a short-range reconnaissance bomber by a team of engineers under the supervision of Aloisem Šmolíkem. Lacking experience in construction metal aircraft, Letov sought and found assistance from Avia. In 1937 a full-size wooden mock-up was demonstrated at the Paris Air Show. The crew of three was seated in fully enclosed cockpits, The navigator-bombardier sat in the forward fuselage with improved glazing, the pilot sat above the wing, and the gunner operated the double 0.312 in (7.92 mm) machinegun in turret on top of the fuselage. A third 0.312 in (7.92 mm) machinegun was fitted in the left wing. A bomb load of up to 1,323 lb (600 kg) could be carried. The aircraft was powered by two 420 hp Avia Rk-17 nine-cylinder radial engines driving two-bladed fixed pitch propellers.

First flight was scheduled for early 1938, but it took till September before test pilot Kovanda took it to the air for the first time, from November it was test pilot Jezek who flew the aircraft. Performance of the Letov Š 50 proved to be modest, the top speed did not exceed 190 mph (305 kmh). Test flying was briefly suspended in March 1939, when after Czechoslovakia became occupied by Germany and the subsequent control takeover of the country's highly developed arms industry.

The aircraft was finished in a camouflage scheme and Czechoslovakian markings and flown again under German control, subsequently it was given the German registration D-OPCO and displayed at Brussels in German markings, whereafter it was transferred to the Rechlin test center. In 1940 it was severely demaged in a test flight and returned to the factory at Letnany, Prague, for repairs. However, this did not materialize and the sole example of the Letov Š 50 was scrapped.

great pictures, anybody know why the Arado had open spinners ?

Another heavy fighter/bomber based on the SM.88 was the SM.92. The SM.92 did away with the mid-wing crew nacelle. The crew of two sat in the left fuselage only. Two DB 605 engines were fitted. Armament consisted of three 20 mm MG 151 cannon, two in the mid-wing and one in the right fuselage, and three 12.7 mm machine guns, one under each engine, and one remotely-controlled in the tail. A bombload of up to 2,000 kg (4,400 lb) could be carried under the inner wing, and 160 kg (350 lb) bombs were carried under the outer wings.

The maximum speed was increased, but still did not meet that required. It had a complex and advanced structure which contributed to difficulties in producing a working prototype. The prototype MM.531 flew for the first time in October 1943 and logged over 21 hours of flight time. In March 1944 it was mistaken for a P-38 Lightning and attacked by a Macchi C.205. The aircraft survived by performing evasive manoeuvres, but it was so badly damaged that it was grounded for months. The SM.92 was destroyed by Allied bombing in 1944.

Acceptance that the concept of the I-180 was outmoded coupled with the prospect of the availability of powerful 18-cylinder radial engines led the Polikarpov OKB to design the I-185 within an extraordinarily short period of time (25 January to 10 March 1940). Intended for the 1,750hp Shvetsov M-90 engine, the I-185 was of mixed construction, having a wooden monocoque fuselage mated with metal wings featuring automatic leadingedge slats a la Bf 109. Armament consisted of twin 12.7mm and twin 7.62mm guns, all fuselage-mounted. Development delays with the M-90 - which, by December 1940, was cleared only for restricted flight testing - resulted in dismantling of the first prototype unflown, this having been known as Samolet (Aircraft) R. A second prototype. Samolet RM, was completed with a Shvetsov M-81 18-cylinder two-row radial and a ducted propeller spinner. This was flown on 11 January 1941, but the M-81 was found to develop insufficient power and was replaced by the Shvetsov M-71 of 1,900hp in May 1941. A third prototype, Samolet I, was completed with a 14-cylinder Shvetsov M-82 engine rated at 1,330hp (later 1,400hp), the fuselage being lengthened for CG reasons from 7.68m to 8.10m, and fuselage-mounted armament being changed to three 20mm cannon. State Acceptance Tests were conducted successfully between 13 April and 5 July 1942. A fourth prototype reverted to the M-71 engine and this underwent operational evaluation on the Kalinin Front alongside Samolet I. A redesigned wing (of single- in place of two-spar construction) was featured by this aircraft, which was tested with both the four-machine gun and three-cannon armament arrangements. A pre-production prototype, the so-called I-185 Etalon (Standard), was flown on 10 June 1942. Regarded as the forerunner of the intended production derivative, the I-186, this standardised on the M-71 engine and three-cannon armament, and had a similarly lengthened fuselage to that of Samolet I. State Acceptance Testing was conducted between November 1942 and January 1943, the NIl VVS evaluation reports describing the I-185 Etalon as "superior to all contemporary fighters." In the event, it was found impracticable to manufacture the M-71 in large numbers and airframe production capacity was unavailable.

The J8M took to the air for its first powered flight on 7 July 1945, with Lieutenant Commander Toyohiko Inuzuka at the controls; Inuzuka successfully jettisoned the dolly upon becoming airborne and began to gain speed, climbing skywards at a 45 degree angle. At an altitude of 1,300 ft, the engine stopped abruptly and the J8M1 stalled. Inuzuka managed to glide the aircraft back, but clipped a small building at the edge of the airfield while trying to land, causing the aircraft to burst into flames. Inuzuka died the next day. While Mitsubishi and naval technicians sought to find the cause of the accident, all future flights were grounded. The engine cutout had occurred because the angle of climb, coupled with the fuel tanks being half-filled for this first flight, caused a shifting of the fuel, which in turn caused an auto cutout device to activate because of an air lock in the fuel line

rochie said:

great pictures, anybody know why the Arado had open spinners ?

Click to expand...

I think it had something to do with engine cooling.

More interesting stuff, keep it coming!

On the XP-41 I believe it was a Pratt&Whitney R-1830-19, not Wright and the engine had a two stage supercharger not two speed. This was a predecessor of the engine used in the Wildcat.

many books and web sites seem to get it wrong.

Many thanks for the effort you are putting into this thread.

The aircraft flew for the first time on 1 April 1940. Engine cooling problems arose in the initial flights, resulting in modification to the oil cooling ducts. Further modifications were made to the prototype including reduction in the height of the cockpit canopy, revising the armament installation to four 0.5 in (12.7 mm) machine guns in place of the cannon, redesign of the engine nacelles, adding spinners to the propellers, and extending the fuselage forward of the wing. These changes were completed on 15 July 1941. Additional changes were needed after further flight tests that were not completed until 15 January 1942. In the meantime, Grumman began work on a more advanced twin-engine shipboard fighter, the XF7F-1, and further testing with the XF5F-1 supported the development of the newer design. The prototype continued to be used in various tests, although plagued by various landing gear problems, until it was struck from the list of active aircraft after it made a belly landing on 11 December 1944.

The first flight of the unique Kyushu J7W Shinden (magnificent lightning), a canard-configuration single-seat fighter, was made on 3 August 1945, but the end of World War II later that month brought an end to development and production plans. Designed by a team under the leadership of Captain Masaoki Tsuruno of the Imperial Japanese Navy, the configuration of this aircraft had been effectively confirmed by the flight testing of three specially designed and built MXY6 gliders. The construction of two J7W1 prototypes followed, these each having a slender fuselage and mounting in a mid-position on the nose a short-span foreplane incorporating elevators at the trailing edge. The rear-mounted cantilever monoplane wing was set low on the fuselage, had moderately swept leading edges and conventional ailerons with, just inboard of these on each wing, a fin and rudder extending above and below the trailing edge. The landing gear was of retractable tricycle type; the pilot was accommodated in an enclosed cockpit, directly above the leading edge of the wing; and power was provided by a 1588kW Mitsubishi MK9D radial engine, mounted in the rear fuselage to drive a six-blade pusher propeller. By the end of the war the second prototype had been completed but not flown.

More pics

The SM.91 might be called the Italian P-38 as it was a twin-engined, twin-boom long-range escort fighter, but it differed from its American counterpart in having a crew of two. Designed in 1941 and competing with the Caproni Ca 380 Corsaro (also a twin-boom design) for production orders, the SM.91 flew for the first time on March 10, 1943, powered by 1475 h.p. Daimler-Benz DB 605A-l twelve-cylinder inverted vee engines. Only one prototype was finished. One of the few all-metal Savoia-Marchetti aircraft, it mounted three forward-firing 20-mm. Mauser MG 151 cannon in the central nacelle and two similar weapons in the wing roots. Four 220-lb. or 353-lb. bombs or a single 1100-lb. bomb (or 218-gal. drop-tank) could be carried externally on racks below the wings and central nacelle. Empty and loaded weights were 14,110 lb. and 19,600 lb. Maximum speed was 363 m.p.h. at 22,960 ft., cruising speed 320 m.p.h., service ceiling 36,090 ft., and range 994 miles. Climb to 19,680 ft. required 8 min. 30 sec. Dimensions were: span 64 ft. 7 1/2 in., length 43 ft. 5 3/4 in., height 12 ft. 7 1/2 in., and wing area 449.5 sq. ft.

In August 1917, the Sopwith Aviation Company started design of a two-seat fighter reconnaissance aircraft intended to replace the Bristol F.2 Fighter, and received permission to build prototypes of the Sopwith FR.2. It was intended to power the FR.2 with a 200 hp (149 kW) Hispano-Suiza 8 water-cooled V-8 engine, but the Hispano was in great demand, and it was decided to switch to the new Clerget 11, an eleven-cylinder rotary engine, a change which led to the prospective design being redesignated 2FR.2. The Bulldog was a compact single-bay biplane resembling the first prototype Sopwith Snipe single-seat fighter. The pilot sat under the upper wing, with his head and shoulders protruding through a large gap in the centre section, while the observer's cockpit was aft of the trailing edge of the upper wing. Armament was two synchronised Vickers machine guns in a hump ahead of the pilot, while the observer/gunner was provided with two Lewis guns, one on a telescopic mounting forward of the observer's cockpit, and the second on a pillar mounting to give rearward defence.

The first prototype appeared early in 1918, but it was overweight and handled poorly. It was quickly rebuilt with much larger two-bay wings, which improved the handling, but the prototype's performance remained disappointing, not even matching that of the aircraft it was intended to replace. The poor performance was in part due to the Clerget engine's failure to provide the expected power, producing only 200 hp (149 kW) instead of the expected 260 hp (194 kW). The second prototype was fitted with a 360 hp (267 kW) ABC Dragonfly radial engine, becoming the Bulldog Mk.II, with the first prototype becoming the Bulldog Mk.I. However, although the Dragonfly gave much more power than the Clerget, it was hopelessly unreliable, with one test pilot stating that "... I never remember being able to get all cylinders to fire at the same time" and "I don't remember that we got a single successful performance with the engine." Work on a third prototype was abandoned because of the failure of the first two aircraft, although the second prototype continued in use until at least March 1919 carrying out test flights in futile attempts to solve the problems of the Dragonfly.

The SK V6 experimental twin-boom light monoplane illustrated here was eventually adapted as the SK SL6 to /light test the control surface arrangement of 8lohm and Voss's proposed "Arrow Wing".

The only bomber Breguet 460 Vultur was a prototype low-wing medium bomber with two Gnome-Rhône 14N engines of 950 ch. that rejected for production. This prototype was flown to Barcelona on November 20, 1936 and remained in Catalonia within the group Night Flight 11. Did not last long, until it crashed or was shot down by ground fire on March 7, 1937. It was probably the best plane camouflaged his time, rain boots units undoubtedly inspired his cryptic scheme, then some fashion. Neither was wearing or other distinguishing number, only the red stripes and the republican flag in the drift.

Interesting stuff!