Oct. 20, 2015 AF Reserve stands up B-1 unit at Dyess The 489th Bomb Group was reactivated as an Air Force Reserve unit during a ceremony here Oct. 17.The 307th Bomb Wing's newly reactivated 489th BG, which encompasses more than 250 Airmen across the 345th Bomb Squadron, 489th Maintenance Squadron and the 489th Aerospace Medical Flight, will be working