Narrative:

737-100's communication radios are dual, 2-HEADED with separate volume controls for each head. During approach with fairly late turnover from approach control to tower, first officer got distracted by traffic and was later (3 mi or so) tuning tower frequency on a head that had had the volume bumped to minimum. After switching back to approach control -- too busy to get a word in -- executed a go around and at about that time figured out the problem. A single volume control per 2 radios would eliminate that problem.

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Original NASA ASRS Text

Title: ACR B-737-100, UNABLE TO ESTABLISH RADIO CONTACT WITH TWR ON SHORT FINAL, EXECUTES A GAR.

Narrative: 737-100'S COM RADIOS ARE DUAL, 2-HEADED WITH SEPARATE VOLUME CTLS FOR EACH HEAD. DURING APCH WITH FAIRLY LATE TURNOVER FROM APCH CTL TO TWR, FO GOT DISTRACTED BY TFC AND WAS LATER (3 MI OR SO) TUNING TWR FREQ ON A HEAD THAT HAD HAD THE VOLUME BUMPED TO MINIMUM. AFTER SWITCHING BACK TO APCH CTL -- TOO BUSY TO GET A WORD IN -- EXECUTED A GAR AND AT ABOUT THAT TIME FIGURED OUT THE PROB. A SINGLE VOLUME CTL PER 2 RADIOS WOULD ELIMINATE THAT PROB.

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.