CREATE TABLE table_15779 ("Week" FLOAT, "Date" CLOB, "Opponent" CLOB, "Result" CLOB, "Game site" CLOB, "Record" CLOB, "Attendance" CLOB)

On what date was the crowd size of 71,789?
SELECT "Date" FROM table_15779 WHERE "Attendance" = '71,789'
SELECT "Date" FROM "table_15779" WHERE "Attendance" = '71,789'