What was found
(CAN) BOTH CAPTAIN AND FIRST OFFICERS SEATS WERE FOUND TO HAVE BROKEN CROSS BRACES AT THE BASE OF THE SEAT. A FLEET CAMPAIGN OF ALL THE OTHER AIRCRAFT WITH THE SAME PARTS SHOWED NO CRACKED OR BROKEN. THE MANUFACTURER NO LONGER MAKES THE SAME PART WHICH HAS HOLES BORED IN IT. THE NEW PART DOES NOT HAVE HOLES WHICH WAS WHERE IT CRACKED AND BROKEN. TUBE/WELD BASE ASSEMBLY REPLACED ON BOTH SEATS AND AIRCRAFT RETURNED TO SERVICE.