What was found
POST FLIGHT TAXI TO TIEDOWN, LEFT TIRE WENT FLAT. DURING REPLACEMENT, TIRE SHOWED NO SIGNS OF DAMAGE. TUBE HAD A SMALL TEAR. CUTTING THE TUBE OPEN SHOWED 2 LINES OF MARKS/THIN SPOTS ON THE INSIDE. THESE LINES ARE ON APPROX EACH SIDEWALL, OPPOSITE THE VALVE STEM, GOING APPROX 33 PERCENT OF THE WAY AROUND THE INSIDE OF THE TUBE. THESE LINES BOTH BY TOUCH AND VISIBLY ARE A THIN SPOT IN THE RUBBER. THE SMALL TEAR WAS FOUND IN THE CENTER OF ONE OF THESE THIN AREAS. CUT OPEN AN 5.00-5 STA TUBE FROM A PREVIOUS TIRE THAT HAD BEEN FLAT SPOTTED AND IT ALSO HAD THE SAME LINES. THEN TOOK A NEW, NEVER USED, TUBE (302-246-401) (G15/6.00-6) AND CUT IT OPEN. IT ALSO HAD THE SAME 2 LINES/THIN SPOTS.