CREATE TABLE table_74809 ("Year" FLOAT, "Driver" TEXT, "Nation of citizenship" TEXT, "Racing series" TEXT, "Type of vehicle" TEXT)

What year has the vehicle of open wheel and a racing series of formula one with a Nation of citizenship in Germany.
SELECT "Year" FROM table_74809 WHERE "Type of vehicle" = 'open wheel' AND "Racing series" = 'formula one' AND "Nation of citizenship" = 'germany'
SELECT "Year" FROM "table_74809" WHERE "Nation of citizenship" = 'germany' AND "Racing series" = 'formula one' AND "Type of vehicle" = 'open wheel'