Los Angeles to Seoul: what the LAX to ICN corridor looks like

Departure
Los Angeles International Airport, Los Angeles, the United States
Arrival
Incheon International Airport, Seoul, South Korea
Great-circle distance
9,627 km (5,198 nm)
Typical airborne time
11h 42m
Usual cruise levels
FL320 to FL410
Initial track
northwest bound

Route overview

The LAX to ICN sector connects Los Angeles International Airport in Los Angeles, the United States, with Incheon International Airport in Seoul, South Korea. Measured along the great circle the two airports are 9,627 km apart, roughly 5,198 nautical miles, which is close to 11h 42m in the air before winds and routing are taken into account. The initial track is northwest bound, and the middle of the route sits in subtropical latitudes.

The East Asian jet stream

Along the way the track passes over the open Atlantic and the open Pacific. The East Asian jet stream dominates the winds along this track. Its core is narrow and its position moves day to day, which is why dispatchers replan the route each cycle. Clear air turbulence sits at the edges of that core, and the WAFS forecast shows where it is expected before the flight departs.

Cruise altitudes on this sector

Ultra long sectors begin cruise lower, often near FL320 because of the fuel load, and finish two or three step climbs higher, up to FL400 or FL410. Choice of level matters because turbulence is layered: a change of two or three thousand feet often puts the aircraft into calmer air, and that is one of the first adjustments a crew will request.

Seasonal pattern

The East Asian jet stream peaks in winter and weakens through the summer, so late summer and early autumn sectors are usually the smoothest on this corridor.

Flying this route with less worry

It is worth remembering that turbulence of the kind found on the LAX to ICN track is uncomfortable and entirely within what the aircraft is built for. Wings are designed to flex, the flight is planned around the forecast, and the crew adjusts level or track when it helps. The live forecast above shows the current picture for this corridor so there are fewer surprises on the day.