What was found
(CAN) AIRCRAFT EQUIPPED WITH EDO59-5250 FLOATS & TAILPLANE MOUNTED AUX.DORSAL FINS PER JOBMASTER STC 305NW.FINS ARE ATTACHED BY BRACKETS. RIBS,LEFT&RIGHT.AN .040"DOUBLER EQUIPPED WITH ANCHOR NUTS REINFORCES THE REAR SPAR.DURING INSP.THE DOUBLERS,SPARS & TAILPLANE SKINS WERE FOUND TO BE SEVERELY CRACKED IN THE AREA AROUND THE ANCHOR NUTS,ON THE LEFT&RIGHT SPAR SECTIONS.IN ADDITION,ONE OF THE TWO FORWARD ATTACHING BRACKETS ON EACH FIN WAS CRACKED.THE POSSIBILITY REAR SPAR CRACKING COULD RESULT IN STRUCTURAL FAILURE OF THE TAILPLANE.