As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE LONGERON THAT CONNECTS THE LEFT FUSELAGE SIDEWALL AND BELLY HAS 1 SPOT OF CORROSION BETWEEN FRAMES 3 AND 4, APPROXIMATE STATION 4100. THE LONGERON IS 3.2MM THICK,AND IS FORMED AS AN ANGLE. THE CORROSION DAMAGE EXTENDS AT LEAST HALFWAY INTO THE BEAM (IN THICKNESS) AND GOES INTO THE BEND RADIUS. THE CORROSION IS ABOUT 1/2" IN DIAMETER. I WILL SEND A DRAWING AND 2 PICTURES. NOTE; FRAME 3 IS AT STATION 3950.