The location of the jet stream is extremely important for aviation. Commercial use of the jet stream began on November 18, 1952, when Pan Am flew from Tokyo to Honolulu at an altitude of 7,600 metres (25,000 ft). It cut the trip time by over one-third, from 18 to 11.5 hours.[28] Not only does it cut time off the flight, it also nets fuel savings for the airline industry.[29] Within North America, the time needed to fly east across the continent can be decreased by about 30 minutes if an airplane can fly with the jet stream, or increased by more than that amount if it must fly west against it.