The Petlyakov Pe-2 (Петляков Пе-2) was a Soviet twin-engine dive bomber used during World War II. One of the outstanding tactical attack aircraft of the war, it also proved successful as a heavy fighter, as a night fighter (Pe-3 variant) and as a reconnaissance aircraft. The Pe-2 was, numerically, the most important Soviet bomber of World War II, at their peak comprising 75% of the Soviet twin-engine bomber force. The Soviets manufactured Pe-2s in greater numbers (11,430 built) during the war than any other twin-engine combat aircraft except for the German Junkers Ju 88 and the British Vickers Wellington. Several communist air forces flew the type after the war, when it became known by the NATO reporting name Buck.
In 1937, Vladimir Petlyakov was the leader of the Heavy Aircraft Brigade at the Tupolev OKB responsible for the development of the ANT-42 four-engined long-range bomber (which would eventually enter service as the TB-7/Pe-8). However, that same year saw the start of Stalin's Great Purge, and none were spared suspicion; Andrei Tupolev, the head of the OKB, was coerced into signing a "confession" in October 1937 that he had formed an anti-Soviet group that included Petlyakov, and both men along with many others were arrested.
Too valuable to be simply executed, unlike many others arrested during the Great Purge, Petlyakov and other weapons designers were instead sent to sharashkas, special prisons run by the NKVD where such valuable prisoners could continue their work under close scrutiny. In 1938, Petlyakov was tasked with leading the first Special Technical Department (STO — SpetsTekhOd'yel) for aviation that also included other future well-known designers such as Vladimir Myasishchev, a colleague of Petlyakov's at the Tupolev OKB.
Because the Russian word for "100" (сотка — "sotka") sounds somewhat like the pronunciation of "STO", the STO was later renamed KB-100, and there Petlyakov proposed the development of a twin-engine interceptor against high-altitude long-range bombers, particularly those being developed in Germany such as the Junkers Ju 86P and Henschel Hs 130.