SELECT state__class_ FROM table_1847180_3 WHERE date_of_successors_formal_installation = "May 11, 1966"
Apa keadaan (kelas) di mana penerus baru dipasang secara resmi pada 11 Mei 1966?
CREATE TABLE table_1847180_3 (state__class_ VARCHAR, date_of_successors_formal_installation VARCHAR)