▁first ▁across ▁the ▁Stra it ▁of ▁Mess ina ▁( Operation ▁Bay town ) ▁on ▁ 3 ▁September , ▁where ▁ 8 0 th ▁H AA ▁R gt ▁( 1 9 4 ▁and ▁ 2 5 0 ▁H AA ▁B t ys ) ▁provided ▁AA ▁cover ▁from ▁Mess ina , ▁followed ▁on ▁ 9 ▁September ▁by ▁land ings ▁at ▁Sal erno ▁( Operation ▁A val anche ). ▁For ▁' A val anche ', ▁ 2 5 2 ▁H AA ▁B ty ▁was ▁in ▁No ▁ 4 ▁Beach ▁Group ▁under ▁ 1 2 ▁AA ▁B de . ▁This ▁time ▁there ▁was ▁no ▁surprise , ▁and ▁the ▁L ST s ▁and ▁L C Is ▁came ▁under ▁air ▁attack ▁and ▁then ▁heavy ▁art illery ▁fire ▁as ▁they ▁approached ▁the ▁be aches . ▁However , ▁cas ual ties ▁among ▁the ▁AA ▁troops ▁were ▁light ▁and ▁all ▁the ▁bre ach ▁groups ▁land ed ▁successfully : ▁the ▁first ▁H AA ▁guns ▁were ▁in ▁action ▁ 4 – 6 ▁hours ▁after ▁land ings ▁began . ▁O pp osition ▁remained ▁strong , ▁and ▁rein for c ements ▁pou red ▁into ▁a ▁tight ly ▁con str icted ▁beach head ▁while ▁heavy ▁fighting ▁continued ▁nearby . ▁Although ▁early ▁warning ▁and ▁communic ations ▁again ▁proved ▁a ▁problem , ▁the ▁H AA ▁sites ▁were ▁able ▁to ▁use ▁their ▁GL ▁rad ar ▁to ▁fire ▁concentr ations ▁against ▁ra iders . ▁On ▁ 1 7 ▁September ▁the ▁advance ▁from ▁the ▁beach head ▁towards ▁Nap les ▁began : ▁so ▁eager ▁were ▁the ▁AA ▁units ▁that ▁Brig ad ier ▁Mort