Last, a division of QinetiQ North America's Technology Solutions Group, says the add-on armor contract is the 330th Contracting Aircraft Sustainment Wing at Robins Air Force Base in Georgia. The deal is for $16.3 million.

Officials say the add-on armor offers additional protection to the aircraft's crucial flight systems and to aircrews as the C-5s operate increasingly in combat zones like Afghanistan and Iraq. The latest Air Force contract adds to Last's already long history of supplying armor for fixed-wing aircraft supporting the Air Force's C-130s and C-17s with add-on armor.

"The Last Armor team's hard work and dedication was vital to the C-5 in supporting its urgent and compelling need to provide armor to the entire C-5 fleet," Thomas Chester, Robins AFB program manager, said in a statement. "This effort will provide protection, survivability of crew and aircraft, and allow for operation of aircraft in critical locations."