Yak-15 'Pero' - Soviet Air Force, 1946
The daring theft of a pre-production Jumo 004B axial flow turbojet engine from the Messerschmitt test facility at Leipeim airfield by Soviet spies in June 1943 enabled the Soviet Union to quickly catch-up with this new technology and before the year was out a team at 26 GAZ, headed by Klimov, were producing copies of the Jumo 004B as the RD-10 for a variety of planned Soviet tactical aircraft including a new single-seat jet fighter designed by the Yakovlev OKB. To save time, Yakovlev based the new design on their successful Yak-3 piston-engined fighter with the RD-10 jet engine mounted underneath the forward fuselage with the jet exhaust exiting underneath the centre fuselage protected by a steel heatshield. The wings and tail were largely unchanged and a useful armanent of two 23mm Nudelman-Suranov NS-23 cannon was added to the new nose section. Designated as the Yak-15 the new aircraft made a successful first flight in April 1944.
However, the successful repelling of the Allied invasion by German forces in June 1944 allowed Germany to bolster their eastern front and slow down the Soviet advance to a crawl and especially during the harsh winter of 1944-45. This delay allowed Germany to deploy more and more advanced weapons and whilst the Me-262's remained largely in the west the radical Blohm & Voss P.170 three-engined 'Schnellbomber' was particularly effective on the eastern front. In February, 1945 the Yak-15 entered service with the 437th Fighter Aviation Regiment at Vodogon in the Novgorod Oblast and finally gave the Soviet Air Force the ability to intercept the P.170 nuisance raiders.