What was found
AIRCRAFT OUT OF SERVICE DUE TO C8 S2 CHECK. WHILE CLEANING AREA TECHNICIAN FOUND INBD LE RIB, AT SLAT TRACK 12, CRACKED BETWEEN TWO FASTENER HOLES. R & R SLAT TRACK 12, INBD LE RIB IAW A319 SRM 51-42-11, PAR 6 A, 7 B & 13.D & PRODUCTION DRAWING D57443551.