A Study on Countermeasures to Prevent Unstable Approach to Improve Aviation Safety

항공안전도 향상을 위한 불안정 접근 방지대책

  • 전제형 (AirBusan 안전보안실) ;
  • 송제환 (AirBusan 안전보안실) ;
  • 정창재 (AirBusan 안전보안실) ;
  • 임세훈 (산림항공본부 항공기획팀) ;
  • 송병흠 (한국항공대학교 대학원 항공운항관리학과)
  • Received : 2018.04.10
  • Accepted : 2018.09.15
  • Published : 2018.09.30


Aviation industry is growing rapidly, and this growth is expected to continue. However, aircraft accident rate is still high, and 65 percent of accidents occur during landing phase due to unstable approach. Therefore, this research analyzed causes and countermeasures of unstable approach. In order to derive countermeasures, this study selected P International Airport as an example case. In addition, this research analyzed A airline's FOQA data, regional Standard Operating Procedures, and 5 years of environmental factors to identified correlation of those contributing factors. In conclusion, his research concluded following results. First of all, because of P International Airport's geological features, pilots are required to conduct Circling Approach, and this advanced maneuver increases workload at the final stage of flight. Secondarily, meteorological factors such as crosswind, seasonal rain front, local visibility contributes unstable approach. Lastly, these geological and meteorological factors are interrelated, and this uncommon environment can decrease circumstantial judgement ability of pilots and jeopardize aviation safety. As a consequence, it is recommended to reinforce the Crew Resource Management and Threat & Error Management systems so that pilots can perceive identical safety target.


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