rd ▁Special ▁Oper ations ▁Squadron ▁were ▁transferred ▁to ▁the ▁R V NA F ▁at ▁the ▁base . ▁ ▁American ▁use ▁▁ 8 th ▁Field ▁Hospital ▁and ▁ 5 7 th ▁Medical ▁Det achment ▁( Hel ic opter ▁Am bul ance ) ▁( H U - 1 A ▁I ro qu ois ) ▁both ▁arrived ▁during ▁April ▁ 1 9 6 2 . ▁▁ 4 9 8 th ▁Medical ▁Company ▁( A ir ▁Am bul ance ) ▁with ▁U H - 1 D s ▁from ▁September ▁ 1 9 6 5 . ▁ ▁From ▁ 1 9 6 7 ▁the ▁ 5 7 1 st ▁Medical ▁Det achment ▁( Hel ic opter ▁Am bul ance ) ▁and ▁the ▁ 2 5 4 th ▁Medical ▁Det achment ▁( Hel ic opter ▁Am bul ance ) ▁both ▁with ▁U H - 1 D s ▁were ▁deployed ▁here . {[ rp | 1 3 9 }} ▁ ▁The ▁US AF ▁Det achment ▁ 1 2 , ▁Th ir teenth ▁Air ▁Force ▁had ▁been ▁supporting ▁R V NA F ▁operations ▁at ▁N ha ▁Tr ang ▁since ▁February ▁ 1 9 6 2 ▁and ▁in ▁May ▁ 1 9 6 2 ▁they ▁were ▁designated ▁the ▁ 6 2 2 3 rd ▁Air ▁Base ▁Squadron ▁and ▁on ▁ 7 ▁June ▁it ▁was ▁assigned ▁to ▁the ▁ 2 nd ▁Advanced ▁E ch el on ▁( 2 d ▁AD V ON ). ▁ ▁In ▁September ▁ 1 9 6 2 ▁the ▁ 2 3 rd ▁Special ▁Air ▁War fare ▁Det achment ▁equ