CREATE TABLE table_19651 ("No. in series" FLOAT, "No. in season" FLOAT, "Title" TEXT, "Directed by" TEXT, "Written by" TEXT, "Original air date" TEXT, "Production code" FLOAT)

On what dates were episodes written by Robert Carlock aired?
SELECT "Original air date" FROM table_19651 WHERE "Written by" = 'Robert Carlock'
SELECT "Original air date" FROM "table_19651" WHERE "Written by" = 'Robert Carlock'