CREATE TABLE table_24399615_8 (airdate VARCHAR, cable_rank VARCHAR, viewers VARCHAR)

When 656000 is the amount of viewers and n/a is the cable rank what is the airdate?
SELECT airdate FROM table_24399615_8 WHERE cable_rank = "N/A" AND viewers = 656000
SELECT "airdate" FROM "table_24399615_8" WHERE "N/A" = "cable_rank" AND "viewers" = 656000