Autor Thema: What if? Lavochkin La-7bis (ASCC 'Finch') Korean People's Army Air Force (조선인민군 공군), 1950  (Gelesen 2563 mal)

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Offline dizzyfugu

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    • FlickR - Mecha, Anime-Charaktere, anderes...
Ganz subtil...



Some background:
The Lavochkin La-7 (Russian: Лавочкин Ла-7) was a piston-engine Soviet fighter developed during World War II by the Lavochkin Design Bureau (OKB). It was a development and refinement of the Lavochkin La-5, and the last in a family of aircraft that had begun with the LaGG-1 in 1938.

By 1943, the La-5 had become a mainstay of the Soviet Air Forces, yet both its head designer, Semyon Lavochkin, as well as the engineers at the Central Aerohydrodynamics Institute (Russian: TsAGI), felt that it could be improved upon. TsAGI refined earlier studies of aerodynamic improvements to the La-5 airframe in mid-1943 and modified La-5FN to evaluate the changes between December 1943 and February 1944 and proved to have exceptional performance.






Using the same engine as the standard La-5FN the modified aircraft had a top speed of 684 kilometers per hour (425 mph) at a height of 6,150 meters (20,180 ft), some 64 kilometers per hour (40 mph) faster than the production La-5FN. It took 5.2 minutes to climb to 5,000 meters (16,404 ft). Main change was the use of more lighter but stronger metal wing spars to save weight.

The La-5, as well as its predecessors, had been built mostly of wood to conserve strategic materials such as aircraft alloys. With Soviet strategists now confident that supplies of these alloys were unlikely to become a problem, Lavochkin was now able to replace some wooden parts with alloy components.
Combat trials began in mid-September 1944 and were generally very positive.






However four aircraft were lost to engine failures and the engines suffered from numerous lesser problems, despite its satisfactory service in the La-5FN. One cause was the lower position of the engine air intakes in the wing roots of the La-7 which caused the engine to ingest sand and dust. One batch of flawed wings was built and caused six accidents, four of them fatal, in October which caused the fighter to be grounded until the cause was determined to be a defect in the wing spar.

Production of the first aircraft fitted with three B-20 cannon began in January 1945 when 74 were delivered. More than 2000 La-7 aircraft were delivered before the war's end, and a total of 5753 aircraft until production ceded in 1946.






Still, the basic concept had more development potential, and as soon as March 1945 work on further improvements for the La-7 started, while in parallel a new type was under development - the La-9, which would enter prototype stage in 1946. An interim type was needed - and this became the La-7bis. It was based on the proven La-7, but already incorporated crucial elements of the future La-9, e. g. its laminar flow wing shape as well as an increased share of light alloy in the construction.






Overall, the La-7bis was tailored to higher operation altitudes than the standard La-7 and was intended to intercept high flying bombers and reconnaissance aircraft like the Ju 388. Therefore the interim type incorporated many small refinements and changes, most notably a bigger wing and fin area, a four-bladed propeller and a pair of new 23 mm Nudelman-Suranov NS-23 cannons which considerably improved firepower and weapon range.






The La-7bis was built in parallel to the standard La-7, but only at Zavod Nr. 99 in Ulan-Ude, where 433 aircraft were built until 1946. Only a few La-7bis reached the front units during WWII in time, and in Soviet service the type was quickly superseded by the La-9. Many aircraft were used in flying schools and training regiments, though, or quickly handed over to allies like China and Korea.

With these operators the La-7bis actively took part in the Korean War and remained in service until the mid-Sixties, when piston fighters were finally replaced by the highly successful MiG-15.








Even though a sub version of the La-7, the type received the separate Air Standardization Coordinating Committee (ASCC) code "Finch" as it was initially mistaken as a new Lavochkin type.









General characteristics:
    Crew: 1
    Length: 8.89 m (29 ft 1 1/2 in)
    Wingspan: 10,16 m (33 ft 3 in)
    Height: 2.41 m (7 ft 11 in)
    Wing area: 19.59 m2 (210.2 sq ft)
    Gross weight: 3,315 kg (7,308 lb)

Powerplant:
    1× Shvetsov ASh-82FN air-cooled 14 cylinder radial engine with a two-stage supercharger and
    fuel injection, 1.380 kW (1.850 hp), driving a 4-bladed VISh-110V propeller

Performance:
    Maximum speed: 680 km/h (422 mph; 367 kn) at 6.000 meters (19.685 ft)
    Range: 665 km (413 mi; 359 nmi)
    Service ceiling: 11.500 m (37.667 ft)
    Rate of climb: 17.25 m/s (3.410 ft/min)
    Time to altitude: 4.8 minutes to 5.000 meters (16.404 ft)

Armament:
    2 × 23 mm Nudelman-Suranov NS-23 cannons, 150 RPG, plus 200 kg (440 lb) of bombs



Entstanden ist dieser Umbau aus einer "übriggebliebene" Hobby Boss La-7, für die ich keine echte Verwendung hatte - aber ich war schon länger scharf auf eine spätere La-9 oder -11. Daher also: selber gebaut, auch wenn es eine fiktive Interims-Version der La-7 geworden ist.

Man sieht es nicht direkt, aber alle Flächen sind verändert:
- Flügelaußenteile einer Matchbox P-51D
- Höhenruder einer Heller P-51D
- Seitenruderoberteil einer Academy Fw190A/F

Dazu wurde der vierblättrige Propeller aus Schrott gescratcht und ein Pilot eingesetzt. Auch die Ölkühler wurden, statt Wanne unter dem Rumpf, in die Tragflächenvorderkanten verlegt (bei der La-11 später in die Motorhaube integriert).




Der Anstrich ist fast authentisch, basiert auf einer echten, nordkoreanischen La-11, nur dass ich die Unterseite hellblau bemalt habe, das Vorbild war vermutlich auch unten hellgrau (wie die Oberseite).








Wie gesagt, sehr subtil - man muss selbst als Kenner der Materie dreimal hingucken um zu sehen, dass bzw. was da nicht alles nicht stimmt!  :police:

« Letzte Änderung: 16. Juni 2017, 11:01:48 von dizzyfugu »