SAS achieved what it called the first "four dimensional (4DT) managed revenue flight ever made." The event occurred on Jan. 19 and involved a 737 from Lulea to Stockholm Arlanda. It also marked the first Advanced Continuous Descent Approach into Arlanda. During the flight, the approach controller and tactical supervisor at Arlanda used data link to set up the approach procedure, enabling the 737 "to calculate its optimum trajectory." The ground also assigned a Required Time of Arrival for the runway threshold. After pilots entered the ATC data into the FMS, the aircraft 4DT trajectory was downlinked to the ground, including precise altitudes and times at all waypoints ahead to touchdown. The aircraft met the previously given RTA within 2 sec