Narrative:

I work in a heavy maintenance shop (hmv) at the air carrier maintenance base. In hangar X we do repairs on landing gear, which is composed of high strength steel. Air carrier manual specifies a process for corrosion removal involving 4-5 steps (i.e., roto peen, cad plating, etc). Both management and engineering told us that if we grit blast the parts with aluminum oxide, we could go ahead and prime and paint. This was their interpretation. We asked for and were never given written confirmation on this, and were later told that we were correct. While this was happening, a few non-routine write-ups were processed and accomplished without following the steps in the manual. The parts were then installed on a B737-300 with no corrective action taken. Callback conversation with reporter revealed the following information: the reporter stated that he was working in a hmv. The mechanics who went to the school on the corrosion removal process were under the impression that after grit blast treatment which generates heat on high strength steel, that a series of inspections must occur to assure the high strength steel has retained its strength: a magnetic particle inspection, a surface temperature etch, roto pining and cadmium plating. By unwritten interpretation these processes are not being accomplished. This landing gear corrosion inspection occurs on the fourth 'C' check or in the sixth yr and the related landing gear assembly has a service life of 8 yrs. So the parts will be discarded anyway in 2 yrs. The reporter suggests a letter of clarification but is unable to get anything in writing.

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Original NASA ASRS Text

Title: LNDG GEAR ASSEMBLY INSTALLED ON ACFT THAT WAS INSPECTED AND PREPARED FOR PAINTING INADEQUATELY.

Narrative: I WORK IN A HVY MAINT SHOP (HMV) AT THE ACR MAINT BASE. IN HANGAR X WE DO REPAIRS ON LNDG GEAR, WHICH IS COMPOSED OF HIGH STRENGTH STEEL. ACR MANUAL SPECIFIES A PROCESS FOR CORROSION REMOVAL INVOLVING 4-5 STEPS (I.E., ROTO PEEN, CAD PLATING, ETC). BOTH MGMNT AND ENGINEERING TOLD US THAT IF WE GRIT BLAST THE PARTS WITH ALUMINUM OXIDE, WE COULD GO AHEAD AND PRIME AND PAINT. THIS WAS THEIR INTERP. WE ASKED FOR AND WERE NEVER GIVEN WRITTEN CONFIRMATION ON THIS, AND WERE LATER TOLD THAT WE WERE CORRECT. WHILE THIS WAS HAPPENING, A FEW NON-ROUTINE WRITE-UPS WERE PROCESSED AND ACCOMPLISHED WITHOUT FOLLOWING THE STEPS IN THE MANUAL. THE PARTS WERE THEN INSTALLED ON A B737-300 WITH NO CORRECTIVE ACTION TAKEN. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THAT HE WAS WORKING IN A HMV. THE MECHANICS WHO WENT TO THE SCHOOL ON THE CORROSION REMOVAL PROCESS WERE UNDER THE IMPRESSION THAT AFTER GRIT BLAST TREATMENT WHICH GENERATES HEAT ON HIGH STRENGTH STEEL, THAT A SERIES OF INSPECTIONS MUST OCCUR TO ASSURE THE HIGH STRENGTH STEEL HAS RETAINED ITS STRENGTH: A MAGNETIC PARTICLE INSPECTION, A SURFACE TEMP ETCH, ROTO PINING AND CADMIUM PLATING. BY UNWRITTEN INTERP THESE PROCESSES ARE NOT BEING ACCOMPLISHED. THIS LNDG GEAR CORROSION INSPECTION OCCURS ON THE FOURTH 'C' CHK OR IN THE SIXTH YR AND THE RELATED LNDG GEAR ASSEMBLY HAS A SVC LIFE OF 8 YRS. SO THE PARTS WILL BE DISCARDED ANYWAY IN 2 YRS. THE RPTR SUGGESTS A LETTER OF CLARIFICATION BUT IS UNABLE TO GET ANYTHING IN WRITING.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.