COMPOSITE FLT CTLS FOR B737-300; B757-200 AND B767 ACFT ARE NOT BEING REPAIRED CORRECTLY PER THE MANUFACTURER'S STRUCTURAL REPAIR MANUAL.

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ROUGHLY 1/3 OF THE SHOP'S WORK OF REPAIRING ALUMINUM FLT CTLS IS REWORK. USUALLY; THE NEW REPAIR HAS DELAMINATED ON THE TRAILING EDGE. HAVING REMOVED BOTH ORIGINAL; MANUFACTURED HONEYCOMB SKINS AND OUR OWN REPAIRED ONES; I KNOW THE DIFFERENCE IS ENORMOUS. PEELING APART ORIGINAL SKIN REQUIRES WHAT LOOKS LIKE A GIANT SARDINE CAN KEY AND THE SKIN (.016 ALUMINUM) TEARS -- INDICATING THE BOND IS STRONGER THAN THE METAL AFTER +/-20 YRS. AGAIN; OUR REPAIRS NEED ONLY THE EFFORT A PAIR OF PLIERS CAN PRODUCE. ALSO; THE REPAIRS MAY HAVE ONLY BEEN IN SVC FOR 1-2 YRS BEFORE DELAMINATING. MY FEAR IS THAT AN AILERON OR SPOILER MAY PEEL APART INFLT. THIS PROB/SIT IS CAUSED BY NOT FOLLOWING PUBLISHED REPAIR PROCS. IN THIS CASE; EG; B737-300 MANUAL; BOEING MAKES IT CLR CURVED SURFACES ARE NOT TO BE REPAIRED USING VACUUM PRESSURE ONLY FOR BONDING. LCL MGMNT CLAIMS THIS STEP DOES NOT APPLY; CITING 'STANDARD ENGLISH PRACTICE.' PROTESTS THAT THE STRUCTURAL REPAIR MANUAL INTRODUCTION OUTLINES A DIFFERENT METHOD; IE; PRECURSOR (1; 2; 3 ETC) IS A 'MAJOR ACTION STEP' ARE IGNORED. THUS; WE DON'T HAVE AN AUTOCLAVE TO REPAIR THE FLT CTLS TO ORIGINAL STRENGTH. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE REWORK BEING DONE IN THE SHOP IS NOT BEING DONE ACCORDING TO THE STRUCTURAL REPAIR MANUAL. THE RPTR SAID THE CTL SURFACES ARE COMING BACK TO THE SHOP AFTER ONLY 1-2 YRS IN SVC BECAUSE OF THE FAILURE OF THE CARBON FIBER/EPOXY TO METAL BOND. THE RPTR STATED THE FAILURE IS CAUSED BY WATER OR MOISTURE REMAINING IN THE FLT CTL AFTER THE REPAIR AND POOR METAL SURFACE BONDING. THE RPTR SAID SOME REPAIRS ARE ACCOMPLISHED 3-4 TIMES TO GET A GOOD SURFACE BOND. THE RPTR SAID THAT AFTER A REPAIR IS MADE AN ULTRASONIC CHK IS MADE TO CHK THE CARBON FIBER/EPOXY BOND TO METAL AND IF THE CHK FAILS; THE CTL IS TORN OPEN TO REWORK. THE RPTR STATES THE STRUCTURAL REPAIR MANUAL REQUIRES THE REPAIRED PART BE PLACED IN AN AUTOCLAVE TO CURE UNDER HEAT AND HIGH PRESSURE INSURING A MOISTURE FREE CTL AND PERMANENT BONDING. THE RPTR STATED THE ACR DOES NOT OWN OR OPERATE AN AUTOCLAVE.