Incheon International Airport is becoming a hub in the Northeast Asia region since its opening in 2001. Along with an increasing volume of air traffic, demands for airspace are also increasing significantly. In particular, air traffic delays have been growing rapidly due to an increasing volume of air traffic, specially flying to Europe through China. And therefore, there should be an alternative protocol to prevent flight delays. The main purpose of this study is to review current West Sea Airways of G597/Y64 which contains highly potential problems and to evaluate the efficacy of double-tracked airways in the west sea area.