What was found
THE OPERATOR HAS A FLEET, SIX, OF THESE AIRCRAFT. A PROBLEM HAD DEVELOPED CONCERNING THE CARBURETOR HEAT AIRBOX. THE COVER IS ATTACHED WITH A PAIR OF SCREWS ON ONE SIDE AND A TONGUE AND SLOT ARRANGEMENT ON THE OTHER. THE SLOTS WEAR OUT AT AN ALARMING RATE CAUSING THAT PART OF THE BOX ASSY TO DEPART THE AIRCRAFT. IN A SHORT TIME, THE CLAMPS HOLDING THE AIRBOX BREAK AND AIR BOX FALLS TO BOTTOM OF COWL. NEW PART BREAKS IN ABOUT 100 HOURS OR LESS.