21. Upon her return, she concentrated increasingly upon honing her antisubmarine warfare ( ASW ) capability. 22. Antisubmarine warfare capabilities received the greatest emphasis as she received a helicopter flight and hangar deck.23. On 23 March, the ship departed for Chinhae and conducted antisubmarine warfare training en route. 24. She got underway on 17 November 1980 to take part in Atlantic Antisubmarine Warfare Exercise 2 81. 25. The first operational battlefield UAV developed by the US military was for antisubmarine warfare ( ASW ). 26. This tour of duty also saw her engaged in various antisubmarine warfare exercises with the Philippine Navy. 27. She remained in Philippine waters into June, varying convoy and patrol duties with antisubmarine warfare exercises. 28. After the Pearl Harbor Attack, the 23d engaged in antisubmarine warfare against German U-boats. 29. Hunter-killer antisubmarine warfare ( ASW ) training prepared the ships to return to the Mediterranean. 30. The targets suddenly turned toward " Tautog " and were recognized as an antisubmarine warfare team.
