The United States is preparing to deploy up to six nuclear-capable B-52 bombers to northern Australia, a provocative move experts say is aimed squarely at China. An investigation by Four Corners can reveal Washington is planning to build dedicated facilities for the giant aircraft at Tindal air base, south of Darwin. The US has drawn up detailed plans for what it calls a "squadron operations facility" for use during the Northern Territory dry season, an adjoining maintenance centre and a parking area for "six B-52s". Plans for the Tindal air base expansion include a parking area that can accommodate six…