What was found
PILOT STOPPED AIRCRAFT ON TAXIWAY DUE VIBRATION FROM NOSE TIRE. MAINTENANCE REPLACED FLAT TIRE. INSPECTION OF TIRE AND TUBE IDENTIFIED A NAIL IN TIRE (UNDETERMINED IF THIS WAS CAUSE OF FAILURE) ADDITIONAL INSPECTION OF TUBE INDICATED POSSIBLE PROBLEM WITH TUBE CONSTRUCTION IN THAT TUBE SHOWS INDICATION OF FAULTY MATERIAL (TUBE TEARS EASILY BY HAND) AND WALL THICKNESS ABOUT HALF OF THAT OF A DIFFERENT TUBE OF THE SAME MFG (AND ABOUT HALF THE WEIGHT). THIS WAS THE LATEST OF A RECENT STRING OF FLAT TIRES FOR UNDETERMINED REASONS. MANUFACTURER NOTIFIED OF FINDINGS. QUESTIONABLE TUBE INDICATED FABRICATION IN EUROPE (HEAVIER TUBE CONSTRUCTED IN CANADA).