South Korea's Seoul-Jeju route is the second busiest route in Asia-Pacific as measured in ASKs, and has emerged as a six-way struggle between the incumbent carriers and low-cost upstarts.
Flightglobal's CapStats database shows that in 2012, six domestic South Korean carriers provided 6.7 million seats from Seoul's two airports to Jeju. The route to the holiday destination, which only falls behind the Tokyo Haneda-Sapporo route in terms of ASKs, has grown over 50% since 2005. That was when just two carriers, Korean Air and Asiana, provided 4 million outbound seats.
The first real challenge to Korean Air and Asiana's dominance of the route emerged in 2008, with the entry of low-cost carriers Jeju Air and South Korean unit Jin Air. In 2009, Eastar Jet entered the fray, followed by T'Way Air in 2010. The last carrier to enter the competitive Seoul-Jeju market was another low-cost player, Air Busan, which commenced services in 2011.
By 2012, Capstats shows that budget carriers accounted for 52% of capacity on the route, although Korean Air and Asiana still hold the greatest capacity share. In 2012, Korean Air commanded 27% of outbound capacity on Seoul-Jeju, while Asiana held 21%.
Both carriers cut capacity on Seoul-Jeju between 2005 and 2012. Korean Air reduced its outbound seats on the route by 657,000 - a 26% reduction - while Asiana reduced its seats by 140,000, or 9%.
Although the Korean Air brand is less prevalent on the route than in the past, the carrier's wholly owned subsidiary Jin Air is the dominant LCC on Seoul-Jeju with a 14% share, or 945,000 outbound seats on the route.
FlightMaps Analytics also underlines South Korean carriers' traditional loyalty to US airframer Boeing. In August 2013, Boeing 737 aircraft accounted for 72% of traffic on the route, with Airbus A320 family aircraft providing just 18%. The balance is provided by a mix of widebody aircraft.