combat unk was the unk bombing Attack ( gdb ) operation Military_operation of the vietnam war by the united states air force using Using bomb directing centrals and by the united states marine corps using Using course directing centrals ( `` unk and unk ground radars '' ) .

combat unk was the unk bombing Attack ( gdb ) operation Military_operation of the vietnam war by the united states air force using Using bomb directing centrals and by the united states marine corps using Using course directing centrals ( `` unk and unk ground radars '' ) .