. ▁Under ▁their ▁secret ▁plan , ▁the ▁V PN ▁deployed ▁the ▁ 1 2 6 th ▁Battalion , ▁a ▁naval ▁special ▁forces ▁unit ▁of ▁about ▁ 1 7 0 ▁personnel , ▁to ▁join ▁the ▁V iet ▁Cong ▁ 4 7 1 st ▁Battalion ▁of ▁Military ▁Zone ▁ 5 . ▁They ▁were ▁supported ▁by ▁three ▁transport ▁ships ▁namely ▁the ▁T 6 7 3 , ▁T 6 7 4 ▁and ▁T 6 7 5 ▁along ▁with ▁ 6 0 ▁experienced ▁sail ors ▁and ▁techn icians ▁from ▁the ▁ 1 2 5 th ▁Naval ▁Transport ▁Brigade . ▁The ▁North ▁Vietnam ese ▁operation ▁would ▁commence ▁at ▁ 1 2 . 0 0   am ▁on ▁April ▁ 9 , ▁ 1 9 7 5 , ▁to ▁co inci de ▁with ▁the ▁North ▁Vietnam ese ▁ground ▁attack ▁on ▁X u ân ▁L ộ c ▁and ▁to ▁take ▁advantage ▁of ▁low ▁t ide ▁to ▁land ▁the ▁special ▁forces ▁on ▁the ▁South ▁Vietnam ese - occup ied ▁sections ▁of ▁the ▁Spr at ly ▁Islands . ▁To ▁maintain ▁the ▁secre cy ▁of ▁their ▁operation , ▁the ▁North ▁Vietnam ese ▁Navy ▁kept ▁their ▁radio ▁communic ations ▁to ▁a ▁minimum ▁in ▁the ▁days ▁leading ▁up ▁to ▁the ▁attack . ▁ ▁South ▁Vietnam ▁Un like ▁their ▁North ▁Vietnam ese ▁counter parts , ▁South ▁Vietnam ▁possessed ▁a ▁large ▁naval ▁force ▁with ▁a ▁strong ▁fleet ▁of ▁ships . ▁Hence ▁the ▁Republic ▁of ▁Vietnam ▁Navy ▁( R V N ), ▁commanded ▁by ▁Vice ▁Admir al ▁Ch ung ▁T ấ n ▁C ang , ▁were ▁able ▁to ▁maintain