Яковлев Як-9: Советский истребитель Второй мировой войны

Fighter aircraft

The Yakovlev Yak 9 (Яковлев Як 9; NATO reporting name: Frank) is a single engine, single seat multipurpose fighter aircraft used by the Soviet Union and its allies during World War II and the early Cold War. It was a development of the robust and successful Yak 7B fighter, which was based in turn on the tandem seat advanced trainer known as the Yak 7UTI. The Yak 9 started arriving in Soviet fighter regiments in late 1942 and played a major role in retaking air superiority from the Luftwaffe's new Focke Wulf Fw 190 and fighters during the grand Battle of Kursk in summer 1943. The Yak 9 had a cut down rear fuselage with an unobscured canopy. Its lighter metal structure allowed for an increased fuel load and armament over previous models built from wood. The Yak 9 was manoeuvrable at high speeds when flying at low and medium altitudes and was also easy to control, qualities that allowed it to be one of most produced Soviet fighters of World War II. It was produced in different variants including the Yak 9T with the cannon and the "large calibre" Yak 9K with a cannon firing through the propeller hub, which was used for antitank duty and as a potent aircraft destroyer, the fighter bomber Yak 9B with an internal bomb bay behind the cockpit for up to worth of bombs, the long range Yak 9D and the Yak 9DD with additional wing fuel tanks to escort bombers over Eastern Europe, and the Yak 9U with a more powerful engine and improved aerodynamics. The Yak 9 remained in production from 1942 to 1948, with 16,769 built (14,579 during the war). After World War II, the Yak 9 would also be used by the North Korean Air Force during the Korean War.

The Yak 9 represented further development of the successful Yakovlev Yak 7 fighter, a production version of the lightened Yak 7DI, taking full advantage of the combat experience with its predecessor. Greater availability of duralumin allowed for lighter construction which in turn permitted a number of modifications to the basic design. Yak 9 variants used two different wings, five different engines, six different fuel tank configurations and seven different armament setups.

During December 1943, the new airframe (Yak 9U) was able to use the M 107A engine, which was more powerful than the previous VK 105PF. The engine installation was new and included individual faired exhaust pipes. The oil cooler intake was moved from beneath the nose to the port wing root as well as an enlarged radiator bath being moved further aft under the fuselage. The supercharger intake was centered on the top decking of the engine cowling. The rear antenna cable was moved inside a lengthened rear canopy which provided the pilot with a better view to the rear, while the rear fuselage was cut down and the horizontal tail surfaces were slightly reduced in size. The wings and fuselage structure were made of metal which was then skinned with Bakelite. The Yak 9U was typically armed with a ShVAK cannon firing through the hollow propeller shaft, and two Berenzin UB machine guns. State trials were carried out from January to April 1944 and revealed that the Yak 9U had a better top speed compared to fighters in service on the Eastern front at Unlike the I 185 the Yak 9U was stable and easy to fly. However, the M 107A engine inherited the problems of the VK 105PF and was prone to overheating, oil leaks, loss of engine pressure during climbs, spark plugs constantly burning out, and intense vibrations which would fatigue assembly bolts leading to a short engine life. These defects forced the first production batches starting during April 1944  to be powered by the more reliable M 105 PF 3 engine. Further changes were made, like increasing the fuel capacity to and in order to re balance the aircraft, the wings were moved forward and the aircraft's Vlsh 107LO propeller being replaced with the older VISH 105S. A total production of 1,134 aircraft were constructed by December 1944. However, at the beginning of the German invasion of the Soviet Union Yak 9's performed poorly against the Luftwaffe because of a lack of training, although by the Battle of Stalingrad they began to perform better. After the Battle of Smolensk, in the second half of 1943, the famed Free French Normandie Niémen unit became a Groupe and was equipped with the Yak 9. The first unit to use the Yak 9U, between 25 October and 25 December 1944, was 163. IAP. Pilots were ordered not to use the engine at combat speed since this reduced its life to two or three flights only. Nevertheless, in the course of 398 sorties, the unit claimed 27 Focke Wulf Fw 190As and one Bf 109G 2, for the loss of two Yaks in dogfights, one to flak and four in accidents. The Yak 9U contributed greatly toward the Soviets gaining air superiority, and the Germans learned to avoid the Yaks “without antenna mast”. A large formation of the Yak 9DD version was transferred to Bari (the capital of Apulia, in Italy) to help Yugoslav partisans in the Balkans. One of the top scoring Yak 9 pilots was First Lieutenant A. I. Vybornov. Flying a type T (equipped with a 37mm NS 37 cannon in the nose) he achieved 19 air victories, plus nine shared and was awarded the Gold Star Medal of the Hero of the Soviet Union in June 1945. At the end of the war, on 22 March 1945, Lieutenant L. I. Sivko from 812th IAP achieved an air victory against a Messerschmitt Me 262 jet fighter, but he was killed soon afterward by another Me 262, probably piloted by Franz Schall, a top scoring Me 262 pilot. Fighter units with this aircraft suffered lower losses than average. Of 2,550 Yak 9s manufactured up the end of 1943, only 383 were lost in combat.

At the beginning of the Cold War, Yak 9 fighters began buzzing American, British, and French flights in the air corridors to West Berlin. During the Berlin Blockade, Yak 9 fighters interfered with the U. S. Air Force Royal Air Force airlift. During 1949, the Soviet Union provided surplus Yak 9P (VK 107) aircraft to some satellite states in the Soviet bloc to help them rebuild their air forces following the West Berlin blockade. A section of the aircraft's operating manual was accidentally omitted from the translation from Russian into some languages: before starting the Yak 9, it was necessary to hand crank a small cockpit mounted oil pump 25 times to provide initial lubrication to the Klimov V12 engine, unlike World War II German and Western fighters equipped with forced closed cycle lubrication systems. Skipping this unusual but vital step resulted in frequent engine seizures during the takeoff roll and initial climb, causing several fatalities during 1950.