Passage: Upon graduation from school in 1977, he worked at a radio equipment plant in Chelyabinsk, Russia. In May 1978, Kornienko was called to service in the Soviet Army. He served in the paratrooper forces in Kirovobad, Azerbaidzhan, the USSR. In May 1980, he completed his military service with the rank of a junior sergeant. Kornienko worked for the Moscow Militia from 1980–1986. At the same time he attended the evening Department of Moscow Aviation Institute. Upon graduation in 1987 from the institute, he was qualified as a liquid propellant rocket engines mechanical engineer. He resigned from the Militia in 1986 and entered a mechanical engineering design bureau. During 1986 to 1991 Kornienko worked in the Baikonur Launch Facility as a launch equipment specialist.

Question: What year did Kornienko graduate?
1977