Mathias Rust Square was jokingly referred to by Muscovites as Sheremetyevo-3 (Sheremetyevo-1 and -2 being the two terminals at Moscow's main international airport). At the end of 1987, the police radio code used by law enforcement officers in Moscow was allegedly updated to include a code for an aircraft landing. Shortly after the incident, SubLogic, the original publishers of the "Flight Simulator" franchise, issued a scenery disk that expanded the original program's coverage area to include the Eastern Bloc. A challenge in the expansion pack was to land in Red Square as Rust had just done. Following the 20th anniversary of his
Mathias Rust air traffic control that he was going to Stockholm, and took off at 12:21 p.m. Immediately after his final communication with traffic control he turned his plane to the east near Nummela. Air traffic controllers tried to contact him as he was moving around the busy Helsinki–Moscow route, but Rust turned off all his communications equipment. Rust disappeared from the Finnish air traffic radar near Espoo. Control personnel presumed an emergency and a rescue effort was organized, including a Finnish Border Guard patrol boat. They found an oil patch near Sipoo where Rust disappeared from radar, and performed an underwater