What was found
SPINNER BULKHEAD DISCOVERED CRACKED AFTER A COMPANY MAINT SAFETY STAND DOWN WHEN OTHERS IN OUR FLEET WERE FOUND CRACKED USING MAGNIFICATION. SINCE THE DISCOVERY ON 4/18/25. THIS ACFT HAS HAD 7 BULKHEAD REPLACEMENTS. AVERAGE TIME BETWEEN BULKHEADS VARIED BETWEEN 50 HRS AND 100 HRS, WITH THE LAST ONE MAKING 200 HRS. WORKING WITH TEXTRON ENGINEERING TO TRY AND FIGURE THIS OUT WHY. FALL OF 2025 WE PURCHASED AN ACES BALANCER & BALANCED THIS ACFT & OUR FLEET. TEXTRON SENT A NEW DESIGNED SPINNER & NEW BULKHEAD THAT IS SAME PART NUMBER TO TEST FOR THEM A MONTH AGO. NO SIGNS OF CRACKS IN FIRST 50 HRS. CHECKED THE VIBRATION, WAS .50 IPS. GOT IT TO .06 IPS & MAY HAVE CONTRIBUTED TO THE LAST BULKHEAD TO 200 HRS. FOR THE TEST WITH TEXTRON, REMOVED THE WEIGHT & IT RETURNED TO A .41IPS. WE HAVE ONE ACFT THAT HAS YET TO HAVE ITS BULKHEAD REPLACED. WHEN CHECKED IT FOR VIBRATION, IT RECORDED AS .05 IPS. AFTER COMPLETING 2 ANNUALS ON 172'S OUTSIDE OUR FLEET AND OLDER MODELS WITH CRACKS, BROUGHT OUR CONVERSATION TO THEM.