Avionics News January 2016 - 27
Aircraft owners with functional audio panels may covet
some of the features available in today's new-generation
While those old units may do the job, they fall short of
providing the benefits available in new-technology audio
panels. Even among today's sport pilots, a new-generation
audio panel holds appeal for the extras available. Those
extras hold particular appeal among pilots and passengers
enthralled by the ability to use their portable devices as much
The variety of options available today is considerable
- many of them a long way from the audio panel's simple
Switch on, switch off
The audio control panel came about to provide a convenient one-box solution to managing audio output from
the prevailing VHF communication and navigation radios
dominant decades ago.
Prior to the advent of the audio control panel, pilots
with multiple radios to manage relied on a scattered array
of switches to switch on or off the audio output of VHF
communications and navigation radios, as well as the audio
received to identify ADF stations - allowing crew and passengers to hear broadcast radio programs from high-power
AM radio stations when flying.
It was an era when the cockpit-communications system
dominant in aircraft cockpits involved shouting at fellow
crew and passengers to be heard above the roar of engines
and props. Intercoms provided the logical step to improve
cockpit communications - and often the intercom involved
throwing a switch to be heard, instead of transmitting on a
The advent of the audio panel brought organization and
centralization to the job of managing audio output from the
sundry radios in the panel, as well as control over the selection of transmitters used to communicate.
A pilot selects which source to listen, and the audio panel
routes those signals into the audio headset channel - or a
cockpit speaker, if so selected. Beyond that basic function,
the audio panel quickly gained ground as the home of other
Audio panel advances over the years included the integration of multiplace intercoms into the box. Audio panels also
became a common home for marker-beacon receivers.
At that point, functionality sort of plateaued. The electronics technology used advanced with the times, but the
functionality changed little until new innovators brought
their own new twists on some old tricks. So began the march
into the 21st century technologies we carry in our phones and
Today, audio panels come in a dizzying variety - different
shapes and form factors, different features.
Audio panels today offer features such as voice-activated
intercoms, digital communications recording, public address
system amplifiers, stereo music players, and phone or satellite radio interfaces. Also big, the pilot-configurable flexibility layered inside the compact boxes, which take up little
panel space - if they even take up panel space.
Some integrated avionics systems make the audio panel
integral to the package and hide out of sight all but the
switches - effectively taking up no additional panel space.
Among today's most sensible, and common features is a
fail-safe mode to assure the pilot of at least one communications-radio connection even should the audio panel itself fail.
But there's no denying that the new features are among the
Continued on following page
THE VARIETY OF OPTIONS AVAILABLE TODAY IS CONSIDERABLE -
MANY OF THEM A LONG WAY FROM THE AUDIO PANEL'S SIMPLE ROOTS.