Hanisch had a long and successful international career competing for East Germany. He medalled in three consecutive editions of the European Athletics Championships, in Helsinki 1971, Rome 1974 and Prague 1978. His only Olympic appearance was the 1980 Summer Olympics held in Moscow, Soviet Union; there too, Hanisch was successful, winning the javelin bronze medal with a throw of 86.72 metres. However, gold in major meets eluded Hanisch. His most notable victory was in the 1979 IAAF World Cup in Montreal, Canada, when he brought the East German team the full points with a throw of 86.48.