On 21 September 1953 a disenchanted North Korean pilot made a decision that changed his life and American history. Lt No (pronounced ro) Kum Suk was through with the North Korean government and determined to make a break for freedom. Lt. No was a fighter company commander in the second Regiment of the North Korean People's Air Force. He thought about defection number of times before, yet could not do it until his unit moved south to Sunan Airfield outside of Pyongyang after the war was over. He normally flew MiG-15bis Red 408, but on that he flew a MiG-15bis with the tactical number Red 2057. His regular aircraft had not arrived at Sunan yet. Number 2057 was normally flown in combat by a pilot named Kim Dea-Soon. It had been one of the first MiGs smuggled by rail back into North Korea from Manchuria after the cease-fire and re-assembled. The "2057" was a recently painted North Korean number, replacing its original Soviet tactical number. The fact that 2057 was a "bis" model, or advanced model of the MiG15, made it more desirable for the Americans. Its VK-1 engine had 1,000 lbs more thrust than the RD-45 engine of the earlier version, and had hydraulic ailerons. It was a real catch for the Air Technical Intelligence Center to get an updated version of this jet.

During his escape, Lt No purposely allowed another pilot to take off first. This was the first flight from Sunan since the war ended, and it was quite an honor. The other pilot readily accepted. Lt No hoped the first pilot would take his time and it would divert attention from his planned escape. He flew as second aircraft in the flight of three. Near the end of his flight, No broke to the south instead of landing in Sunan. It took only about thirteen minutes to make a straight approach. He made a downwind landing with F-86s landing on the same runway, scaring the pilot to death. He parked alongside an F-86 sitting alert on the ramp. He jumped down and began shaking hands. Although he did not know it at the time, the US offered $100,000 to the first pilot to fly a MiG-15 to the south. He found out at a news conference. The MiG was partially disassembled by Air Tactical Intelligence Center at Kimpo and flown in a C-124 to Kadena AB, Okinawa to be test-flown. PROJECT ZETA began. The USAF removed the North Korean markings and replaced them with small USAF markings. The US pilots did 11 test flights, and pushed the MiG probably harder that the Russians ever tested it. Test engineers had to modify some of the instrumentation, yet found the MiG very easy to work on.