On 18 March 2016 at night and with visibility just above the minimum permitted for landing with thick fog patches present, an Airbus A319 entered the runway at Cheongju contrary to its clearance as a Boeing 737-800 was landing on it as cleared. Only when the 737 crew saw the other aircraft ahead when still at high speed were they able to initiate an immediate lateral deviation and avoid a collision by creating a 3 metre separation between the two aircraft. The Investigation found that the A319 had exceeded its clearance and remained on the Ground frequency but noted poor controller phraseology.