Narrative:

On arrival at aircraft, mechanic was working on first officer communication control panel. After liftoff, unable to receive or transmit to ord. Squawked communication failure on transponder, maintained VFR on top and turned on course. Also attempted to listen on VOR. Relief pilot removed first officer's radio control panel and communication was restored to captain's side. ATC advised that communication failure was well done but squawk should have been 7600 versus 7500. Called company and suggested swapping second observer's panel for failed unit. After checking out the part numbers, company maintenance approved the swap. System restored to normal. Flight continued to destination.

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Original NASA ASRS Text

Title: LOST COMS RADIO FAILURE.

Narrative: ON ARR AT ACFT, MECH WAS WORKING ON FO COM CTL PANEL. AFTER LIFTOFF, UNABLE TO RECEIVE OR XMIT TO ORD. SQUAWKED COM FAILURE ON XPONDER, MAINTAINED VFR ON TOP AND TURNED ON COURSE. ALSO ATTEMPTED TO LISTEN ON VOR. RELIEF PLT REMOVED FO'S RADIO CTL PANEL AND COM WAS RESTORED TO CAPT'S SIDE. ATC ADVISED THAT COM FAILURE WAS WELL DONE BUT SQUAWK SHOULD HAVE BEEN 7600 VERSUS 7500. CALLED COMPANY AND SUGGESTED SWAPPING SECOND OBSERVER'S PANEL FOR FAILED UNIT. AFTER CHKING OUT THE PART NUMBERS, COMPANY MAINT APPROVED THE SWAP. SYS RESTORED TO NORMAL. FLT CONTINUED TO DEST.

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.