CREATE TABLE table_26808178_3 (original_air_date VARCHAR, us_viewers__millions_ VARCHAR)

Which original air date had 0.871 U.S. viewers (millions)?
SELECT original_air_date FROM table_26808178_3 WHERE us_viewers__millions_ = "0.871"
SELECT "original_air_date" FROM "table_26808178_3" WHERE "0.871" = "us_viewers__millions_"