The existing lighting system was too bright, making it difficult for boom operators to observe the refueling process.
The U.S. will seek reimbursement for $331 million from Saudi Arabia and the United Arab Emirates.
The Saudi-led coalition striking Houthi rebels in Yemen is losing roughly one to two tankers worth of U.S. fuel per day.
A KC-135 damaged by Tropical Storm Maria in the Pacific last month will be out of commission until at least October.
The Air Force is still inspecting its KC-10 fleet weeks after one of the aircraft experienced slide-raft deployment issues.
Gen. Joseph Votel said working with Saudi Arabia has proven successful even as the civil war in Yemen has continued on.
The refueling effort, which was approved last week, is intended as a show of support for the Gulf Cooperation Council states.
Marine Corps aircraft crews are conducting refueling training in southern New Mexico.
The 380th Air Expeditionary Wing's fuel farm offloaded 255 million gallons of fuel in 2016 for the refueling of U.S...