May 1, 2000
Buying
with Bower
New Avionics: A World of Options
by Ron Bower
I AM OFTEN ASKED QUESTIONS related to avionics by people who want to buy a
helicopter: What should I buy? What is new? What components should I keep from
a used helicopter?
Avionics technology is still on the move. Much of it centers on GPS. In
1991, I flew a Bell JetRanger across the
Now, the plethora of GPS choices include color
maps, seemingly endless databases, displays for weather information, radar,
TCAS depiction, and checklists. A recently announced Honeywell display even has
a video input capability.
The new Garmin 430 units combine VHF nav and comm radios with the GPS
unit, saving weight and panel space. As size and weight decrease, display
screen dimensions for the mapping function continue to increase. In addition,
prices are falling as computing power is on the rise.
For VFR-only helicopters, ADFs have little value.
Most ADF switches I see are in the antenna position rather than in the ADF
position, which suggests how they are really used today. As the VOR/ILS system
fades, filling the panel with dual VHF nav radios is
becoming a waste of weight and space.
Likewise, DMEs have lost their value. These
line-of-sight VHF nav radios always had limited value
for low-flying helicopters, anyway, due to range limitations caused by the
earth’s curvature.
Buyers may be better off by budgeting for a "clean sheet" approach
and getting the panel the way they want it.
New-panel tips
Here are a few tips that you might want to incorporate if you are redoing a
panel:
• Move the units you look at or touch the most to the top of the stack. This
is more important for GPS receivers, particularly those with mapping features.
I like having GPS equipment mounted on top of the console in more of a
"head-up display" presentation (though such installations will need
additional approval).
• Consider dual GPS systems the way you once considered dual nav/comm systems. Use one unit for normal navigation and
one to scan the route ahead for airports, obstacles or airspace restrictions.
• Consider cyclic-mounted switches for frequency paging on comms, or idents on transponders.
Many cyclic grips have switches that aren’t being used.
• Intercom systems and audio panels have vastly improved as well, with pilot
or crew isolation and voice activation now common. If you or your passengers
need background entertainment, consider a tape or CD AM/FM unit that can be
piped into the intercom.
Typically, automotive units are used; therefore, 12-volt converters that
step down the voltage from 24 volts are required. If you install one of these
12-volt converters, consider some additional 12-volt lighter-plug outlets to
charge cell phones, run video cameras, power handheld scanners or business
radios, or even run laptop computers.
Cell phones are FCC-legal if installed "for ground use only" and
can also be piped into headsets. If you use handheld scanners or other radio
receivers in your flying, consider installing "aux" input jacks on
the intercom/audio panel so you can hear those transmissions in your headsets.
If the helicopter doesn’t have a radio master switch already, put one in—it
will save you money from wearing out the breaker switches in many radios.
However, put your intercom on the battery bus, not the radio master. This will
allow you to communicate easily with your passengers through your headsets
anytime you have the battery on, from before the blades start turning until
after they have stopped.
If you have your panel reworked, consider a few other items—maybe a
fuel-flow analyzer (tied into your GPS) that tells you how much fuel you will
have remaining at the destination. You can also install a "generator
fail" caution light, or at least a digital voltage meter like a Davtron five-function unit, which can tell you how the
battery or electrical system is doing.
IFR equipment
For IFR-certified helicopters, the differential GPS (DGPS) system will
radically alter GPS panel equipment and autopilot interfaces in the coming
years.
Nick Lappos of Sikorsky Aircraft has performed
flight tests using experimental helicopter DGPS approaches in conjunction with
Honeywell, Raytheon and the FAA. Lappos is convinced,
and I agree wholeheartedly, that we have only seen the tip of the iceberg in
making navigation safer through GPS technology. Ground proximity or terrain
avoidance warnings could be done easily by combining existing databases with
the accuracy of modern GPS systems.
By the way, putting together an electronic emergency survival kit is not a
bad idea. On cross-country flights, I carry my cell phone, a handheld GPS,
handheld VHF comm transceiver, paper map, and a
compass. If I plan to fly over harsh or isolated terrain, I carry a handheld
emergency locator transmitter, since ELTs are not
FAA-mandated for helicopters.
* * *
In a recent column answering a reader’s question about autohover,
I stated that I knew of no civilian helicopter autopilots that had such
capability. Alain Laflamme from
Both the