AN SMA HELI IS DEVELOPING LAMINATION CRACKS IN IT'S ROTOR BLADES AT A FASTER RATE THAN THE MAINT SUPVR FEELS IS SAFE.

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BLADE ROTATION LAMINATES SHOWED SIGNS OF CRACKING/BREAKAGE. THIS CONDITION IS SOMEWHAT NORMAL AND WELL-ADDRESSED BY MANUFACTURER. SOME CRACKING IS ALLOWED. ALTHOUGH LAMINATES WERE STILL WITHIN PUBLISHED LIMITS; IT SEEMED TO ME THAT THEY WERE RAPIDLY APCHING AN UNSERVICABLE CONDITION. I WAS CONCERNED THAT DUE TO THE SPD AT WHICH THESE CRACKS WERE OCCURRING THAT WE MIGHT NOT SEE THE PART GO FROM MERELY 'UNSERVICABLE' TO 'DANGEROUS.' AFTER NUMEROUS DISCUSSIONS WITH MGMNT AND MANUFACTURER REPRESENTATIVES; I CAME TO THE CONCLUSION THAT MY CONCERN IS LARGELY UNWARRANTED. HOWEVER; SOME DOUBT REMAINS AS TO THE SAFETY OF OPERATING A PART THAT IS APCHING ON SVCABILITY FASTER THAN GENERALLY EXPECTED. SOLUTION: MANUFACTURER SHOULD INCLUDE SOME CRITERIA IN INSPECTION MANUAL FOR RATE OF DETERIORATION; NOT JUST AMOUNT OF DETERIORATION; IE; ONE CRACK PER 100 HRS; ETC. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO. THE RPTR; A AND P MECH WITH INSPECTION AUTHORIZATION; STATES THAT HE HAS FILED AN MMIR (MAINT MALFUNCTION INFO RPT) WITH THE FAA REGARDING THE RATE OF DETERIORATION OF THE BLADES ON THE HELI FOR WHICH HE IS RESPONSIBLE. HIS COMPANY HAS ONLY ONE OF THIS TYPE OF HELI; BUT HE HAS HEARD THROUGH THE GRAPEVINE THAT OTHER OPERATORS ARE HAVING SIMILAR PROBLEMS.