CREATE TABLE table_17356205_1 (original_air_date VARCHAR2, directed_by VARCHAR2)

What is the original air date of the episode directed by Terrence Nightingall?
SELECT original_air_date FROM table_17356205_1 WHERE directed_by = "Terrence Nightingall"
SELECT "original_air_date" FROM "table_17356205_1" WHERE "Terrence Nightingall" = "directed_by"