Narrative:

On departing pit, our PNF switched ATC departure frequency to our #2 communication. Then later returned the ATC departure frequency to #1 communication receiver. On return to #1 communication, PNF turned volume down by mistake. PF didn't notice the mistake or lack of ATC communications. After a few mins of no ATC communication, an investigation found the volume to be turned down. The communication radio volume knob is very easy to move on this radio when frequencys are changed. In the future this crew will monitor frequency changes more closely and check volume after frequency changes when using this type of communication radio. On return to ATC frequency, controller did not note any major problems. The rest of the flight was uneventful, using greater care to monitor communication volume on frequency changes.

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Original NASA ASRS Text

Title: ACFT EQUIP DESIGN PROB IS CONTRIBUTORY TO TEMPORARY LOSS OF COM FREQ RADIO CONTACT.

Narrative: ON DEPARTING PIT, OUR PNF SWITCHED ATC DEP FREQ TO OUR #2 COM. THEN LATER RETURNED THE ATC DEP FREQ TO #1 COM RECEIVER. ON RETURN TO #1 COM, PNF TURNED VOLUME DOWN BY MISTAKE. PF DIDN'T NOTICE THE MISTAKE OR LACK OF ATC COMS. AFTER A FEW MINS OF NO ATC COM, AN INVESTIGATION FOUND THE VOLUME TO BE TURNED DOWN. THE COM RADIO VOLUME KNOB IS VERY EASY TO MOVE ON THIS RADIO WHEN FREQS ARE CHANGED. IN THE FUTURE THIS CREW WILL MONITOR FREQ CHANGES MORE CLOSELY AND CHK VOLUME AFTER FREQ CHANGES WHEN USING THIS TYPE OF COM RADIO. ON RETURN TO ATC FREQ, CTLR DID NOT NOTE ANY MAJOR PROBS. THE REST OF THE FLT WAS UNEVENTFUL, USING GREATER CARE TO MONITOR COM VOLUME ON FREQ CHANGES.

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.