Narrative:

Reporter left center frequency, while copilot (PF) monitored center frequency. Due to the cockpit design, 3 buttons must be pushed to (eg copy ATIS) on VHF #2 in addition to actually tuning in the ATIS frequency. If a successful radio transfer is not accomplished (only indicator lights confirm this, there are no audible or fingertip felt clicks), center frequency is lost from the electronic tuning head (VHF #1, #2, and #3 are accessed from the same tuning head). Although this makes for a compact cockpit installation, I feel this is a poor design on this aircraft that will continually cause this type of problem. Airlines will not tolerate the cost of redesign. Callback conversation with reporter revealed the following information: during callback the reporter indicated that the only deviation was a temporary (2 min) interruption of communication with center. There was no altitude, track or other deviation. The reporter contends that the design of the VHF communication tuning system is a major contributor to this and other related occurrences of pilot induced loss of communications. There are 3 VHF communication radios in this type advanced technology large transport, and all 3 are accessed through a common tuning head. There is both an active and standby frequency 'window' for all 3 radios, thus, there exists the potential for confusion as to which communication radio is being served by either the active or standby frequency displays. There is no FAA investigative follow-up in this incident.

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Original NASA ASRS Text

Title: DESIGN OF RADIO COM SELECTOR HEADS IMPLICATED IN FLC LOSS OF COM WITH ARTCC.

Narrative: RPTR LEFT CENTER FREQ, WHILE COPLT (PF) MONITORED CENTER FREQ. DUE TO THE COCKPIT DESIGN, 3 BUTTONS MUST BE PUSHED TO (EG COPY ATIS) ON VHF #2 IN ADDITION TO ACTUALLY TUNING IN THE ATIS FREQ. IF A SUCCESSFUL RADIO TRANSFER IS NOT ACCOMPLISHED (ONLY INDICATOR LIGHTS CONFIRM THIS, THERE ARE NO AUDIBLE OR FINGERTIP FELT CLICKS), CENTER FREQ IS LOST FROM THE ELECTRONIC TUNING HEAD (VHF #1, #2, AND #3 ARE ACCESSED FROM THE SAME TUNING HEAD). ALTHOUGH THIS MAKES FOR A COMPACT COCKPIT INSTALLATION, I FEEL THIS IS A POOR DESIGN ON THIS ACFT THAT WILL CONTINUALLY CAUSE THIS TYPE OF PROBLEM. AIRLINES WILL NOT TOLERATE THE COST OF REDESIGN. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: DURING CALLBACK THE RPTR INDICATED THAT THE ONLY DEV WAS A TEMPORARY (2 MIN) INTERRUPTION OF COM WITH CENTER. THERE WAS NO ALT, TRACK OR OTHER DEV. THE RPTR CONTENDS THAT THE DESIGN OF THE VHF COM TUNING SYS IS A MAJOR CONTRIBUTOR TO THIS AND OTHER RELATED OCCURRENCES OF PLT INDUCED LOSS OF COMS. THERE ARE 3 VHF COM RADIOS IN THIS TYPE ADVANCED TECHNOLOGY LGT, AND ALL 3 ARE ACCESSED THROUGH A COMMON TUNING HEAD. THERE IS BOTH AN ACTIVE AND STANDBY FREQ 'WINDOW' FOR ALL 3 RADIOS, THUS, THERE EXISTS THE POTENTIAL FOR CONFUSION AS TO WHICH COM RADIO IS BEING SERVED BY EITHER THE ACTIVE OR STANDBY FREQ DISPLAYS. THERE IS NO FAA INVESTIGATIVE FOLLOW-UP IN THIS INCIDENT.

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.