150714-N-BX824-049 TIMOR SEA The Ticonderoga-class guided-missile cruiser USS Antietam fires its Mk 45 5-inch gun during a towed drone unit live-fire exercise in support of Talisman Sabre 2015. TS 15 is a biennial exercise that provides an invaluable opportunity for nearly 30,000 U.S. and Australian Defence Forces to conduct operations in a combined, joint and interagency environment that will increase both countries' ability to plan and execute a full range of operations from combat missions to humanitarian assistance efforts.