What was found
WHILE A/C WAS IN FOR HEAVY CHECK FOUND LT WHEEL WELL FWD BULKHEAD (RIB 52) WEB REPAIR DOUBLER CRACKED. MX REMOVED, FABRICATED, AND INSTALLED NEW RIB IAW EMB 170/175 SRM 51-40-03, AND ETD 2012-170/004153 CRACK LENGTH .75" TOP CENTER OF DOUBLER. A/C REMAINS IN CMH FOR HEAVY CHECK COMPLETION.