Blohm & Voss Bv P.202 (Unicraft Models, Resin)

TYPE: Variable-wing fighter. Project


POWER PLANT: Two BMW 003 turbojet engines, rated at 850 kp each

PERFORMANCE: No data available

COMMENT: The Blohm & Voss P 202 was an unusual design study for a variable-geometry turbojet fighter during World War II. It was the first design to incorporate a slewed wing (also known as an oblique or scissor wing) in which one side swept forward and the other back.
During WW II in Germany intensive work has been done in concern of influence back-swept wings on high-speed aircraft. Calculations as well as wind-tunnel tests showed that swept wings could minimize the effects of compressibility as the speed of sound was approached. But sweeping the wings causes problems of its own, especially at the low speeds used for takeoff and landing. A variable-sweep mechanism was one possible solution but it would be complex, heavy and expensive. It also has problems with movement of the centre of lift. Both backwards and forwards sweep were investigated and they proved to have opposite disadvantages. Sweeping one wing forwards and the other back would balance out the aerodynamic problems and a one-piece slewed wing approach would not need such a complex sweep mechanism.
In 1944, with their project Bv P.202 the design team of Blohm & Voss tried to compensate the disadvantage of swept-back wings a low speed by turning a single full-span wing in its yaw axis so that one side sweeps back and the other side sweeps forward. The shoulder mounted wing was shaped as a disc in the mid-wing section. During take-off and landing as well as at lower speed the wing was in rectangular position with all buoyancy forces such as airbrakes and spoilers still effective. At high speeds the whole wing was slewed at 35° that the left wing showed forward and the right wing backward. The wing span was 39.4 ft when unswept and 32.8 ft when fully swept. Because the fuselage was filled with wing-rotation machinery, the landing gear extended down from the wing main spar, and was very long, while the nose gear retracted backwards into the fuselage. The Blohm & Voss Bv P.202 was powered by a pair of BMW 003 turbojets, slung underneath the fuselage center section and exhausting behind the wing. Provision for three forward-firing cannon was made in the nose. Due to the war situation in Germany the project never left the drawing board (Ref.: 18, 24).

Mitsubishi Ki-46-III (Army Type 100 Command Reconnaissance Plane Model 3), (DINAH), (Army Special Attack Unit “Sakura”), (LS-Models)

TYPE: Reconnaissance and fighter aircraft


POWER PLANT: Two Mitsubishi Ha-112-II Army Type 4 radial engines, rated at 1,500 hp each

PERFORMANCE: 404 mph at 19,095 ft

COMMENT: The Mitsubishi Ki-46 was a twin-engine reconnaissance aircraft used by the Imperial Japanese Army in WW II. Its Army  designation was Type 100 Command Reconnaissance Aircraft; the Allied nickname was DINAH.
At the beginning of the conflict the newest versionf of the Ki-46-II were able to performe their missions with almost complete freedom from interception as, without the benefit of ground control radar to guide them, the Allied squadron‘ obsolescent fighters failed to reach the elusive Nipponese aircraft in time.
When the USAAF deployed Lockheed P-38F Lightnings to the Pacific and the RAAF received some  Spitfire Supermarinere Mk.V for the defence of Darwin, the losses suffered by Ki-46-II units began to mount. Fortunately for the Japanese, the Koku Hombu had anticipated this situation and in May 1942 had instructed Mitsubishi to install their new 1,500 hp Ha-112-II engine in an improved version of the aircraft, the Ki-46-III, to increase maximum speed to 404 mph and endurance by one hour. To meet the requirement for increased flight duration, despite the higher fuel consumption of the new engines, it was necessary to redesign the fuel system and add a fuselage fuel tank in front of the pilot with a resultant increase in total capacity from 1,675 litres to 1,895 litres. Provision was also made for a ventral drop tank containing an additional 460 litres. The engine nacelles were also slightly enlarged to accommodate the Ha-112, a development oft he earlier Ha-101 engine fitted with a direct fuel injection system. The landing gear was strengthened to cope with the increased weight and no provision was made for a single flexible machine gun which, though installed on earlier models at the factory, had often been dispensed with in the field. However, the most significant change in external appearance was the redesign oft he foreward fuselage to provide a new canopy over the pilot’s seat without the step between the nose and the top of the fuselage which had characterized the earlier versions of the aircraft.

Completed in December 1942, two Ki-46-III prototypes underwent accelerated flight trials leading to a production order under the designation Army Type 100 Command Reconnaissance Plane Model 3. Both, the Ki-46-II, which remained in production until late in 1944, and the Ki-46-III were built at the Nagoya plant. However, when in December 1944 this plant was severely damaged by an earthquake and suffered further from the pounding inflicted by Boeing B-29 Superfortress’s oft he US 20th Air Force, production was transferred to a new plant at Toyama where only about one hundred machines were built. Late production Ki-46-IIIs coming off the Nagoya and Toyama lines were fitted with individual exhaust stacks providing some thrust augmentation and had sightly better speed and range.
Priority in delivery oft he Ki-46-IIIs was given to units operating in areas where Allied forces had achieved air superiority, but often they operated alongside the older Ki-46-IIs which they never completely supplanted. Once maintenance problems with the fuel injection system of the Ha-112-IIs engines had been solved, the Ki-46-IIIs, benefiting from markedly improved performance between 26,250 ft to 32,810 ft, proved to be a thorn in the Allies‘ side and only the faster climbing fighters under radar controll could successfully intercept the fast Nipponese machines which kept constant watch over the well defended bases as the B-29 airfields in the Marianas. However, as the war drew to its end, the Mitsubishi DINAH was no longer free from interception and losses rose alarmingly.
In total 609 Ki-46-III production aircraft, including fighter conversions were delivered between 1942 and 1945.
The aircraft shown here belongs to the Army Special Attack Unit “Sakura”, Kanoya Base, Kagoshima (Ref.: 1).