What was found
IMPACT DAMAGE FOUND IN C CHANNEL AFT OF F19. REMOVED DAMAGED C CHANNEL AND INTERCOSTALS AT F18 AND F19 THAT WERE MODIFIED TO ACCEPT A PREVIOUS REPAIR TO OLD C CHANNEL. FABRICATED NEW INTERCOSTALS FOR F18 AND F19. ALL NEW PARTS WERE ACID ETCHED, ALODINED AND PRIMED WITH 511K011 SUPER KOROPON BEFORE INSTALLATION. INSTALLED NEW INTERCOSTALS AND C CHANNEL AS REQUIRED. C CHANNEL WAS INSTALLED. CONTINUED AIRWORTHINESS WILL BE MAINTAINED IAW CURRENT INSPECTION PROGRAM OR AIRCRAFT MANUFACTURERS INSPECTION PROGRAM. WEIGHT & BALANCE CHANGE WAS CONSIDERED NEGLIGIBLE.