Narrative:

On 5/tue/00 I was assigned to repitch the power port wiring. I work on a light C check of the B757 fleet. The sidewalls are pulled for other maintenance, exposing the power port harnesses. I observed that the harnesses were not spiral wrapped near the power port boxes or where the harness goes across each aircraft frame, nor were boxes grounded. This same situation happened on a previous aircraft and it was determined that the grounds would be added later on a separate eco. It was also determined that the harnesses would be spiral wrapped at the frames and near the boxes. Also where they come thru the sidewall panel. On aircraft xyz, management changed its mind and told us the spiral wrapping would be put off for yet another separate eco. Eco #wxxx, wyyy, wabc were all red lined to eliminate spiral wrapping of harnesses. I view this as an unsafe condition that the company is aware of, yet we as mechanics are told to let it slide because they determined it is not unsafe. Callback conversation with reporter revealed the following information: the reporter stated several unsafe conditions exist with the seat computer power port wiring harness and power port boxes. The reporter said the power port boxes supply approximately 20 seats with dc power and is mounted to a frame between the sidewall panels and the fuselage skin. The reporter said the box has 3 phase 115/120 volts AC power input and the seat dc supply wiring snakes between the frames and sidewalls with no spiral wrap protection for the wiring insulation. The reporter stated the power port box, input AC harness and output dc harnesses are not grounded to aircraft structure. The reporter said all of these discrepancies were reported to management as not in compliance with the maintenance manual electrical procedures. The circuit breakers for this system are located in the electrical and electronics compartment and not accessible to the crew in flight.

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Original NASA ASRS Text

Title: A B757-200 DURING MAINT THE CABIN SIDEWALLS WERE REMOVED EXPOSING THE SEAT PWR PORT WIRING HARNESSES WHICH WERE IN NON COMPLIANCE WITH THE MAINT MANUAL ELECTRICAL PROCEDURES.

Narrative: ON 5/TUE/00 I WAS ASSIGNED TO REPITCH THE PWR PORT WIRING. I WORK ON A LIGHT C CHECK OF THE B757 FLEET. THE SIDEWALLS ARE PULLED FOR OTHER MAINT, EXPOSING THE PWR PORT HARNESSES. I OBSERVED THAT THE HARNESSES WERE NOT SPIRAL WRAPPED NEAR THE PWR PORT BOXES OR WHERE THE HARNESS GOES ACROSS EACH ACFT FRAME, NOR WERE BOXES GROUNDED. THIS SAME SITUATION HAPPENED ON A PREVIOUS ACFT AND IT WAS DETERMINED THAT THE GROUNDS WOULD BE ADDED LATER ON A SEPARATE ECO. IT WAS ALSO DETERMINED THAT THE HARNESSES WOULD BE SPIRAL WRAPPED AT THE FRAMES AND NEAR THE BOXES. ALSO WHERE THEY COME THRU THE SIDEWALL PANEL. ON ACFT XYZ, MGMNT CHANGED ITS MIND AND TOLD US THE SPIRAL WRAPPING WOULD BE PUT OFF FOR YET ANOTHER SEPARATE ECO. ECO #WXXX, WYYY, WABC WERE ALL RED LINED TO ELIMINATE SPIRAL WRAPPING OF HARNESSES. I VIEW THIS AS AN UNSAFE CONDITION THAT THE COMPANY IS AWARE OF, YET WE AS MECHANICS ARE TOLD TO LET IT SLIDE BECAUSE THEY DETERMINED IT IS NOT UNSAFE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED SEVERAL UNSAFE CONDITIONS EXIST WITH THE SEAT COMPUTER PWR PORT WIRING HARNESS AND PWR PORT BOXES. THE RPTR SAID THE PWR PORT BOXES SUPPLY APPROX 20 SEATS WITH DC PWR AND IS MOUNTED TO A FRAME BTWN THE SIDEWALL PANELS AND THE FUSELAGE SKIN. THE RPTR SAID THE BOX HAS 3 PHASE 115/120 VOLTS AC PWR INPUT AND THE SEAT DC SUPPLY WIRING SNAKES BTWN THE FRAMES AND SIDEWALLS WITH NO SPIRAL WRAP PROTECTION FOR THE WIRING INSULATION. THE RPTR STATED THE PWR PORT BOX, INPUT AC HARNESS AND OUTPUT DC HARNESSES ARE NOT GROUNDED TO ACFT STRUCTURE. THE RPTR SAID ALL OF THESE DISCREPANCIES WERE REPORTED TO MGMNT AS NOT IN COMPLIANCE WITH THE MAINT MANUAL ELECTRICAL PROCEDURES. THE CIRCUIT BREAKERS FOR THIS SYSTEM ARE LOCATED IN THE ELECTRICAL AND ELECTRONICS COMPARTMENT AND NOT ACCESSIBLE TO THE CREW IN FLT.

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.