ACFT EQUIP PROB. BORESCOPE PLUG MISSING. RPTR MECH; UNFAMILIAR WITH ACFT TYPE; WAS ASSIGNED JOB OF INSTALLING BORESCOPE PLUGS. RPTR SAYS THAT THE NUMBER OF PLUGS HE INSTALLED COINCIDED WITH THE AMOUNT SHOWN ON THE JOB CARD. AFTER ACFT WAS IN FLT THEY HAD INTERMITTENT FIRE WARNINGS AND ON POST FLT INSPECTION A BORESCOPE PLUG MISSING.

Narrative

I AM A MECH AT AN AIRLINES AT THE Y FACILITY. ON JUN/TUE/96 I WAS GIVEN JOB TO INSTALL THE BORESCOPE PLUGS ON THE #4 ENG ON A B747-400 ACFT NOSE. I NORMALLY DO NOT WORK ON B747'S AND I AM NOT VERY FAMILIAR WITH THEM. I AM CURRENTLY ASSIGNED TO A B757 DOCK. THIS PARTICULAR DAY I WAS WORKING OVERTIME AND HAD BEEN ASSIGNED TO A B747 DOCK THAT WAS LOW ON MANPOWER. ON THE NIGHT OF JUN/THU/96; I WAS OFF FROM WORK BUT RECEIVED A PHONE CALL AT HOME. I WAS TOLD THAT THE ACFT ON RTE TO XXX EXPERIENCED INTERMITTENT FIRE WARNING LIGHTS; THEY DID NOT HAVE TO SHUT DOWN THE ENG. UPON INSPECTION ON THE GND THEY DISCOVERED 1 BORESCOPE PLUG MISSING. I DO RECALL PERFORMING THE JOB ALTHOUGH OFF HAND I CANNOT RECALL EVERY PLUG THAT I PUT IN. THERE WERE SEVERAL OF THEM TO BE INSTALLED; I DID INSTALL EVERY BORESCOPE PLUG I FOUND TO HAVE BEEN TAKEN OUT; I PUT ANTI-SEIZE ON THE THREADS; I TORQUED THEM; AND I SAFETY WIRED THEM. AFTER I INSTALLED THEM; I COUNTED THE ONES I PUT IN AND THAT NUMBER DID COINCIDE WITH THE AMOUNT CALLED OUT IN THE JOB CARD. WHEN I WAS THROUGH I WENT OVER THE ENG TO SEE IF THERE WAS ANYTHING I MISSED; WHEN I WAS SATISFIED THAT THERE WASN'T; I SIGNED IT OFF.