[3] Approximately two months after the end of hostilities, he defected to South Korea in a MiG-15 aircraft, and was subsequently granted political asylum in the United States.

No's support for Imperial Japan waned and he became pro-Western, though he had to hide these views due to the dangers of being recognized in northern Korea at the time.

[6] However, No had to keep his anti-Communist views hidden, due to the danger of what would happen if North Korean authorities had found out about them.

At the naval academy, No won the favor of his history professor who later helped No in the pilot selection test.

[7] On the morning of September 21, 1953, No flew his Mikoyan-Gurevich MiG-15 from Sunan just outside Pyongyang to Kimpo Air Base in South Korea.

[10] During the flight, he was not chased by North Korean aircraft (as he was too far away), nor was he interdicted by American air or ground forces;[10] U.S. radar near Kimpo had been shut down temporarily that morning for routine maintenance.

[10] Another American pilot, Captain Jim Sutton, who was circling the airport, said that if No had tried to land in the right direction, he would have been spotted and shot down.

[10] No taxied the MiG into a free parking spot between two Sabre jets, got out of the plane and began tearing up a picture of Kim Il Sung that was placed in the cockpits of North Korean aircraft, and then threw up his arms in surrender at approaching airbase security guards.

[14] One of the pilots and a friend in his squadron, O Kuk-ryol, became a General and was considered by some the second most powerful man in North Korea.

[4][15] A biography of No by Blaine Harden was published in 2015 as The Great Leader and the Fighter Pilot: The True Story of the Tyrant Who Created North Korea and The Young Lieutenant Who Stole His Way to Freedom.