Pilot's Guide to Avionics 2014-2015 - 73

being detected by air traffic control radar to ADS-B In
equipped aircraft . The TIS-B service is provided within a
15-nautical mile radius, up to 3,500 feet above or below
the receiving ADS-B In aircraft's position .
A general aviation aircraft equipped with ADS-B
In can also receive position data directly from
other aircraft broadcasting on the same
ADS-B Out frequency . ADS-R (automatic
dependent surveillance-rebroadcast)
relays position information broadcast by
ADS-B avionics on the 1090 MHz ES
link to aircraft receiving data on the 978
MHz UAT link and vice versa . The ADSR service is provided within a 15-nautical
mile radius and plus or minus 5,000 feet of
airspace volume relative to the receiving aircraft's
position .
Many avionics repair shops contacted by the Federal
Aviation Administration for this article have already installed ADS-B equipment on a dozen or more aircraft to
meet the agency's 2020 equipage mandate . The FAA
wants to assist them and aircraft owners with guidance on
how to complete installations correctly . Proper adherence
to certain technical details is essential .
There are about 150,000 unequipped aircraft that need
to have ADS-B Out installed . Based on this, the FAA and
repair shops are recommending that aircraft owners begin
accomplishing installations as soon as possible . This will
help aircraft owners avoid being caught in the expected
rush of activity leading up to the 2020 deadline .
When aircraft are equipped with ADS-B Out, controllers
are provided with increased position updates and without
need for interrogation by ground-based radar systems .
"One of the things I tell people is that right now there
may be no hurry, but they shouldn't let the ADS-B installation go past 2016," said John DenDekker, general manager for Carpenter Avionics at Smyrna Airport in Smyrna,
Tennessee . "The last three years of installations before
the mandate will be crazy . Waiting until then means a pilot
can't take advantage of ADS-B In services, which are being broadcast to aircraft today ."
Transponder-equipped aircraft that fly in controlled
airspace today will need ADS-B Out when the mandate
takes effect in 2020 . That's far enough away that many
ADS-B installations can be done now when aircraft are in
for other work .
"If we are doing installation work on an aircraft, ADSB is just an add-on right now," said Chuck Gallagher,
manager of Cincinnati Avionics at the Clermont County

Airport in Batavia, Ohio . "If the aircraft is opened up for
other avionics work, ADS-B is not a hard sell ."
Gallagher also expressed concern that general aviation
aircraft owners will wait until the last minute to add ADSB, and by then there may not be enough capacity
at U .S . repair shops to equip them all by the
deadline .
Repair shop operators say aircraft
owners and operators may be delaying
because they are confused about what to
do . But the experience of early adopters
is helping the general aviation community
understand how to proceed .
To make installation easier to understand,
the FAA Flight Standards Service's Aircraft
Maintenance Division is providing a list of frequently asked questions and a checklist to guide repair
shops:
*

ADS-B Transmitters and
Position Sources.
(See ADS-B Essentials, Part 2.)
This list of frequently asked questions explains
that ADS-B transmitters must be compatible
with installed GPS position sources . The transmitters and position sources cannot be mixed
and matched . They must be installed in approved pairings detailed in a list of equipment
on this FAQ that meets FAA certification requirements . This list is current as of April 2014 .

ADS-B Avionics Installation Guidance.
(See ADS-B Essentials, Part 3.)
This checklist provides guidance on the installation of approved ADS-B Out avionics on aircraft with a standard airworthiness certificate
as well as the installation of uncertified ADS-B
Out avionics on aircraft with an experimental
airworthiness certificate . The checklist also covers common problems involved in such installations and briefly explains how to deal with them .
It discusses how to install both a 1090 MHz ES
and a UAT system on the same aircraft . When
properly configured, these systems allow pilots to
take full advantage of available ADS-B broadcast
services and capabilities at all altitudes .

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Pilot's Guide to Avionics 2014-2015

Table of Contents for the Digital Edition of Pilot's Guide to Avionics 2014-2015