San Francisco to Tokyo: what the SFO to NRT corridor looks like
- Departure
- San Francisco International Airport, San Francisco, the United States
- Arrival
- Tokyo Narita International Airport, Tokyo, Japan
- Great-circle distance
- 8,227 km (4,442 nm)
- Typical airborne time
- 10h 04m
- Usual cruise levels
- FL340 to FL400
- Initial track
- northwest bound
Route overview
San Francisco International Airport (SFO) in San Francisco, the United States, to Tokyo Narita International Airport (NRT) in Tokyo, Japan, is a great-circle distance of 8,227 km, about 4,442 nautical miles. At typical jet cruise speeds, and with an allowance for climb, descent and approach, that works out to roughly 10h 04m of airborne time. The great-circle track leaves San Francisco northwest bound and spends most of the flight in subtropical air.
The East Asian jet stream
Along the way the track passes over the open Atlantic and the open Pacific. This corridor lies under one of the strongest sustained upper winds on the planet, the East Asian jet stream. Eastbound flights ride it and arrive earlier, westbound flights are routed around the core to avoid the headwind. The turbulence here is clear air turbulence generated at the jet boundary, and it is a well mapped, well forecast feature of the region.
Cruise altitudes on this sector
Long haul crews normally start cruise around FL340, then step climb toward FL380 or FL400 as the aircraft burns off fuel and can hold a higher level. 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
Turbulence on this corridor is a comfort issue rather than a safety one. Airliners are certified to handle loads well beyond anything the atmosphere produces here, crews are trained for it, and the seat belt sign is the tool that keeps the cabin settled. What this page adds is knowing in advance: the map and Calmness Score above use current WAFS forecast data for SFO to NRT, so you can see what to expect before you board.