CREATE TABLE table_55011 ("Date" CLOB, "Ship" CLOB, "Type" CLOB, "Nationality" CLOB, "Tonnage GRT" FLOAT)

Which Date has a Ship of hallbjorg?
SELECT "Date" FROM table_55011 WHERE "Ship" = 'hallbjorg'
SELECT "Date" FROM "table_55011" WHERE "Ship" = 'hallbjorg'