GREAT FALLS, Mont. (AP) — The first of 20 F-15 fighter jets assigned to the Montana Air National Guard has left Great Falls for Fresno, Calif., as the 120th Fighter Wing begins changing its mission.

Col. Pete Hronek says one fighter left Tuesday, four more are scheduled to leave over the next few weeks and seven more will move in September. The final eight will move around October.

Equipment related to the F-15s is also being moved to California.

MANG also is preparing for eight C-130 cargo planes that are expected to start arriving this fall.

Hronek tells the Associated Press that an environmental assessment needs to be completed, crew members need training and some construction needs to be done.

The mission change is expected to cost MANG 45 full-time jobs and 35 part-time jobs.