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Gagarin's selection for the Vostok programme was overseen by the Central Flight Medical Commission led by Major General Konstantin Fyodorovich Borodin of the Soviet Army Medical Service. He underwent physical and psychological testing conducted at Central Aviation Scientific-Research Hospital, in Moscow, commanded by Colonel A.S. Usanov, a member of the commission. The commission also included Colonel Yevgeniy Anatoliyevich Karpov, who later commanded the training centre, Colonel Vladimir Ivanovich Yazdovskiy, the head physician for Gagarin's flight, and Major-General Aleksandr Nikolayevich Babiychuk, a physician flag officer on the Soviet Air Force General Staff to the Commander in Chief of the Air Force. The commission limited their selection to pilots between 25 and 30 years old. The chief engineer of the programme Sergei Korolev also specified that candidates, to fit in the limited space in the Vostok capsule, should weigh less than and be no taller than ; Gagarin was tall.