Narrative:

Problem arose from placing hand-held microphone back in its stowed position by feel, without looking. The bracket on our -200 series B757 is close to the sidewall. The microphone was placed with the press to talk switch against the sidewall and the opposite portion of the microphone against the aft side of the retaining bracket. The first officer (PNF) left the cockpit and I was anticipating a change over from ZAU to ZOB. The radios also seemed more quiet than normal. When the first officer returned, I asked if he knew the frequency for ZOB as I thought that ZAU forgot to give us the change over and we were now out of range. The first officer looked up some frequencys, tried to get one from lansing approach. I squawked 7600, and used dispatch to get us the ZOB frequency. Dispatch sent 2 messages via ACARS with the frequencys. These frequencys did not seem to work either. The first officer used radio #2 to contact lan approach and made contact. First officer could not raise ZOB on radio #2. I had looked down at the hand-held microphone and noticed the improper placement in the bracket. I had put it back properly and our lost communication/stuck microphone problem went away. Through CRM, 3 persons were involved, and not one recommended to look for a 'stuck microphone.' more technical proficiency about causes of lost communication would probably have been more useful.

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Original NASA ASRS Text

Title: AN ACR B757 FLC HAD A STUCK MIKE EXPERIENCE WHEN THE CAPT PUT HIS HAND-HELD MIKE BACKWARDS IN ITS HOLDING BRACKET THEREBY CONTINUALLY DEPRESSING ITS XMIT BUTTON. THIS CONDITION LASTED QUITE SOME TIME AS THE FLC WENT THROUGH A NUMBER OF XCHKS AND ALTERNATIVE COM PROCS.

Narrative: PROB AROSE FROM PLACING HAND-HELD MIKE BACK IN ITS STOWED POS BY FEEL, WITHOUT LOOKING. THE BRACKET ON OUR -200 SERIES B757 IS CLOSE TO THE SIDEWALL. THE MIKE WAS PLACED WITH THE PRESS TO TALK SWITCH AGAINST THE SIDEWALL AND THE OPPOSITE PORTION OF THE MIKE AGAINST THE AFT SIDE OF THE RETAINING BRACKET. THE FO (PNF) LEFT THE COCKPIT AND I WAS ANTICIPATING A CHANGE OVER FROM ZAU TO ZOB. THE RADIOS ALSO SEEMED MORE QUIET THAN NORMAL. WHEN THE FO RETURNED, I ASKED IF HE KNEW THE FREQ FOR ZOB AS I THOUGHT THAT ZAU FORGOT TO GIVE US THE CHANGE OVER AND WE WERE NOW OUT OF RANGE. THE FO LOOKED UP SOME FREQS, TRIED TO GET ONE FROM LANSING APCH. I SQUAWKED 7600, AND USED DISPATCH TO GET US THE ZOB FREQ. DISPATCH SENT 2 MESSAGES VIA ACARS WITH THE FREQS. THESE FREQS DID NOT SEEM TO WORK EITHER. THE FO USED RADIO #2 TO CONTACT LAN APCH AND MADE CONTACT. FO COULD NOT RAISE ZOB ON RADIO #2. I HAD LOOKED DOWN AT THE HAND-HELD MIKE AND NOTICED THE IMPROPER PLACEMENT IN THE BRACKET. I HAD PUT IT BACK PROPERLY AND OUR LOST COM/STUCK MIKE PROB WENT AWAY. THROUGH CRM, 3 PERSONS WERE INVOLVED, AND NOT ONE RECOMMENDED TO LOOK FOR A 'STUCK MIKE.' MORE TECHNICAL PROFICIENCY ABOUT CAUSES OF LOST COM WOULD PROBABLY HAVE BEEN MORE USEFUL.

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.