CREATE TABLE table_2818164_5 (no_in_season VARCHAR, original_air_date VARCHAR)

What episoe number in the season originally aired on February 11, 1988?
SELECT no_in_season FROM table_2818164_5 WHERE original_air_date = "February 11, 1988"
SELECT "no_in_season" FROM "table_2818164_5" WHERE "February 11, 1988" = "original_air_date"