AN UNINTENTIONAL ROOF FALL WAS DISCOVERED ON 2 NW MAINS @ 7:30AM DURING AIR COURSE EXAMINATION. THE ROOF FALL MEASURED 5'HIGH X 18'WIDE X 25'LONG. MINE PROPS WERE SET FLOOR TO ROOF & AREA DANGERED OFF. THE FALL IS LOCATED DIRECTLY ACROSS SPAD #3047 (#6 ENTRY) IN THE #7 ENTRY. ESCAPEWAY WAS NOT AFFECTED.