What was found
(CAN) AFTER LANDING AND DURING TAXI, THE LEFT OUTBOARD WHEEL HALF SEPARATED ALONG THE CIRCUMFERENCE. THE WHEEL HAD BEEN INSPECTED AT THE LAST TIRE CHANGE AND WAS OK. NO DAMAGE TO LANDING GEAR AS A RESULT OF SEPARATION. INVESTIGATION AFTER THE INCIDENT REVEALED THAT AN EXISTING CRACK OF 3.5 INCHES LONG SUDDENLY INCREASED LEADING TO THE FRACTURE. AN NDT CHECK AT EVERY TIRE CHANGE IS NOW IN FORCE. PART TC: 355.