Narrative:

After being told to expect a visibility approach to ord 27R on a base leg vector of 180 degrees, we experienced a loss of communications with approach control. #2 VHF radio was tried twice with no positive results. As we had not been cleared for approach, the captain elected to turn left to avoid the flow of other traffic. Transponder was set to 7700 to initiate loss of communications identify procedures. At this time the captain recognized the problem as a stuck microphone, and after unplugging the defective microphone, communications were reestablished. Aircraft was landed with no further problems. On ground, microphone was written up and maintenance was notified. The above was what the captain elected to do. Initially, when I saw we were going through the final approach course, captain called approach and it was then apparent loss of radios had occurred. I opted to start a turn to runway and use light signals, but captain said to turn left to 090 degrees to stay out of traffic flow. I did as instructed during this critical phase of flight. WX was VFR. I did as instructed. Turned out well.

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Original NASA ASRS Text

Title: TRACK HEADING DEVIATION AS FLT CREW EXPERIENCES LOSS OF RADIO CONTACT WITH APCH CTL.

Narrative: AFTER BEING TOLD TO EXPECT A VIS APCH TO ORD 27R ON A BASE LEG VECTOR OF 180 DEGS, WE EXPERIENCED A LOSS OF COMS WITH APCH CTL. #2 VHF RADIO WAS TRIED TWICE WITH NO POSITIVE RESULTS. AS WE HAD NOT BEEN CLRED FOR APCH, THE CAPT ELECTED TO TURN LEFT TO AVOID THE FLOW OF OTHER TFC. XPONDER WAS SET TO 7700 TO INITIATE LOSS OF COMS IDENT PROCS. AT THIS TIME THE CAPT RECOGNIZED THE PROB AS A STUCK MIC, AND AFTER UNPLUGGING THE DEFECTIVE MIC, COMS WERE REESTABLISHED. ACFT WAS LANDED WITH NO FURTHER PROBS. ON GND, MIC WAS WRITTEN UP AND MAINT WAS NOTIFIED. THE ABOVE WAS WHAT THE CAPT ELECTED TO DO. INITIALLY, WHEN I SAW WE WERE GOING THROUGH THE FINAL APCH COURSE, CAPT CALLED APCH AND IT WAS THEN APPARENT LOSS OF RADIOS HAD OCCURRED. I OPTED TO START A TURN TO RWY AND USE LIGHT SIGNALS, BUT CAPT SAID TO TURN LEFT TO 090 DEGS TO STAY OUT OF TFC FLOW. I DID AS INSTRUCTED DURING THIS CRITICAL PHASE OF FLT. WX WAS VFR. I DID AS INSTRUCTED. TURNED OUT WELL.

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.