SELECT "Retired" FROM table_824 WHERE "Aircraft type" = 'Airspeed Fleet Shadower'
How many Airspeed Fleet Shadower aircraft are retired?
CREATE TABLE table_824 (
    "Aircraft type" text,
    "National Origin" text,
    "1st Flight" real,
    "In Service" text,
    "Retired" text,
    "# built" text
)