National Aerospace Solutions LLC, Arnold Air Force Base, Tennessee, has been awarded an $185,599,572 cost-plus-award-fee modification (P00139) to contract FA9101-15-C-0500 for test operations and sustainment. This modification adds Option Year Five for test operations, technology development, equipment and facility sustainment, capital improvements and some support services for the Arnold Engineering Development Complex. Work will be performed at Arnold AFB, Tennessee, and is expected to be completed June 30, 2022. No funds are being obligated at the time of award. This modification brings the total cumulative face value of the contract to $1,517,987,024. Air Force Test Center, Arnold AFB, Tennessee, is the contracting activity.