Throughout the Cold War the USSR flew Tokyo Express flights nearby Japan . From 1967 to 1987 , Soviet aircraft had violated Japanese airspace 20 times . On September 6 , 1976 Soviet pilot Viktor Belenko had flown his MiG-25 to Hokkaido in order to defect to the United States . Japanese radar had been unable to adequately track him , and the F-4EJ fighters of the 302nd Tactical Fighter Squadron launched from Chitose Air Base had been unable to intercept him . This was a major embarrassment and led to changes in the Japanese air defense system
defect to the United States
Defection of Viktor Belenko
1987 Okinawan Tu-16 airspace violation