A B737-400 WAS DISPATCHED AND OPERATED FOR 3 DAYS IN NON COMPLIANCE WITH THE INCORRECT FLT DATA RECORDER INSTALLED DURING AN ENGINEERING ORDER.

Narrative

ON JUL/SUN/04; ENGINEERING ORDER WAS SCHEDULED BY THE PLANNING DEPT TO BE ACCOMPLISHED ON ACFT X. I WAS ASSIGNED THIS TASK BY MY LEAD. I GOT THE ENGINEERING ORDER AND READ THROUGH IT GLANCING AT THE ACFT EFFECTIVITY NOTED ON THE FIRST PAGE OF THE ENGINEERING ORDER. I SAW ACFT Y; Z; W; XY; AND ASSUMED I HAD THE CORRECT ENGINEERING ORDER. I OVERLOOKED THE FACT THAT ACFT X WAS NOT ON THE LIST OF EFFECTIVE ACFT. THIS ENGINEERING ORDER REPLACES THE ANALOG FLT DATA RECORDER WITH A SOLID STATE UNIT. I INSTALLED THE FDR (FLT DATA RECORDER) PER THE AMM INSTRUCTIONS CALLED FOR IN THE ENGINEERING ORDER THEN COMPLETED THE ENGINEERING ORDER PAPERWORK AND MADE A LOGBOOK ENTRY STATING THE ENGINEERING ORDER WAS ACCOMPLISHED. INFLT; THE FDR 'OFF' LIGHT ILLUMINATED; JUL/SUN/04. AGAIN ON JUL/MON/04; THE 'OFF' LIGHT ILLUMINATED INFLT; THE FDR WAS REPLACED. ON JUL/TUE/04; THE AVIONICS SHOP NOTIFIED MAINT THAT 'AILERON SURFACE POS' PARAMETER WAS MISSING AND DIRECTED THE FDR TO BE PLACED ON MEL 31-2B. THE STATION ASSIGNED TO TROUBLESHOOT THE MISSING PARAMETER WAS HAVING DIFFICULTIES. THIS GOT ENGINEERING INVOLVED WHERE IT WAS DISCOVERED THE FDR CALLED OUT BY THE ENGINEERING ORDER WAS NOT EFFECTIVE FOR THIS ACFT. AT THE TOP OF THE FIRST PAGE OF THE ENGINEERING ORDER WAS A 'NOTE' STATING THE ENGINEERING ORDER WAS NOT TO BE ACCOMPLISHED UNLESS SCHEDULED BY PLANNING OR ACCOMPANIED BY AN ENGINEERING AUTH. I ASSUMED THE PLANNING DEPT WOULDN'T ISSUE THE ENGINEERING ORDER UNLESS IT NEEDED TO BE ACCOMPLISHED. BY NOT CAREFULLY READING THE LIST OF EFFECTIVE ACFT; I MISSED THE FACT THAT ACFT X WAS NOT LISTED TO HAVE THIS ENGINEERING ORDER ACCOMPLISHED.