Some 1,100 troops and 90 aircraft from both sides were mobilized for the semiannual Freedom Flag exercise, which runs through May 2, according to the Air Force, Yonhap news agency reported.
Among the assets mobilized for the two-week drills were the South's F-35A, F-15K and KF-16 fighter jets, as well as the US F-16 and F-35 B fighters and MQ-1 and MQ-9 drones.
Over the next two weeks, troops will take part in key air operations training programs, such as air interdiction, defensive counter air, combat search and rescue and close air support exercises.
For the first time, stealth fighter jets, such as the F-35, will take on the role of "red air" enemy forces to help enhance pilots' practical combat capabilities, the Air Force said.
Freedom Flag was launched last year to replace regular large-scale air exercises between the allies -- Korea Flying Training in the first half of the year and Vigilant Defense in the second half.