Avionics News May 2018 - 32

Working with
Dynon, EAA took
the first step of
earning an AML STC
that installed the
Dynon EFIS-D10A
that started with
the Cessna 172.
Photo courtesy of EAA

RISK AND REWARD

Continued from page 31

G5 variant that can replace a directional gyro," he added,
again providing the details of the risk-benefit analysis. The
bonus is that it displays either a traditional DG or an HSI,
the mechanical version of which many aircraft owners
would like to have but cannot afford.
"Modern solid-state equipment is much more reliable
and, hence, safer, and we extended that to the GFC 500,"
a digital STC autopilot that pairs nicely with the G5. Loss
of control is a leading safety concern now, and one benefit
of the autopilot is its Electronic Stability Protection, which
nudges the airplane back into a safe flight envelope.

Photo courtesy of Garmin

Garmin is building its line of STC installations with individual
G5 replacements for the attitude indicator and directional
gyro/HSI, followed by the GFC 500 autopilot that addresses
the risk of loss of control.
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avionics news

may

2018

What separates experimental avionics from their
STC-installable siblings is their verification against
FAA-accepted standards and meeting the airworthiness
requirements that earn them the certification that enables
their legal installation in certificated aircraft. "The way we
view the world, we need to do that product by product,"
Stone said.
The D10A and G5 were the low-hanging STC fruit. The
L3 Aviation Products Trilogy and the Sandia Aerospace
SAI 340 Quattro appear to be competitors in the STC
arena, but both are marketed as electronic replacements for
mechanical standby attitude indicators. That certification
doesn't automatically qualify them as electronic
replacements for primary instruments in Part 23 aircraft.
Sandia introduced the Quattro before the supplemental
type certification of the D10 and G5. "Ours is TSO'd,"
said Sandia President Dennis Schmidt. It recently earned
its eighth TSO certification, adding Instantaneous Vertical
Speed to its capabilities, which eliminates the six- to eightsecond lag inherent in analog vertical speed indicators.
With its certification, the Quattro can be an EFIS backup
or replace a six-pack attitude indicator. The Quattro "is
an unaided solution," said Schmidt, meaning it receives
no outside input like GPS. "When you do a standby, the
purpose is to work when everything fails. If that outside
input fails, you don't have a standby instrument anymore.
That's why the (D10 and G5) are not certified as standbys."
While the Quattro can meet both applications, Sandia
hasn't seen any real growth in the six-pack replacement
market, according to Schmidt. "That market has grown,
there are more people in it, so the pie has to be getting
bigger, but we're not relying on it," he said.
"L3's Trilogy and our other standby instruments,
including the newer ESI-500, cannot be used as a primary
attitude indicator in Part 23 aircraft," said Cathy Gedvilas,
L3 media marketing communication manager. "Their use
is as standby units with existing attitude indicators in the
cockpit, as approved by the FAA under STCs."

Table of Contents for the Digital Edition of Avionics News May 2018