Avionics News June 2017 - 30

ADS-B REBATE HELPS OPERATORS EQUIP
Continued from page 29

"The three most serious errors that we regularly see are
transmission of a wrong ICAO code, an incorrect flight identification or call sign, and dual Out boxes using different ICAO
codes," Marks said.
ADS-B has an FAA-assigned 24-bit ICAO code. This code is
different from the flight identification, which should match the
aircraft's N-number. The installation technician must enter this
information to comply with the rule, and glitches do occur. One
of the ADS-B Focus Team's highest priorities is to promptly
contact any aircraft owner with incorrect ICAO codes or flight
identification. The FAA handles about 200 of these cases per
month. Call sign mismatch is a related issue for aircraft using a
call sign instead of an N-number. This issue does not arise for the
vast majority of general aviation operators, but requires allowing
call sign entry for those affected.
The third issue is a twist of technology. When the ADS-B

explained. "Also, if your aircraft is equipped with ADS-B In,
you may see a second aircraft displayed very close to your
own position, prompting you to try to avoid an aircraft that
isn't there."
The ADS-B Focus Team also is working on a reporting
issue called air/ground determination. The FAA has detected
ADS-B-equipped aircraft reporting in airborne mode while
taxiing or stationary. This problem stems from issues with the
ADS-B avionics that make the actual air/ground determination
and relay that information to the FAA's ADS-B system. The
FAA is working with avionics manufacturers to better understand the issue and determine how to resolve it.

Final Steps
"We emphasize making sure your installation is compliant
with the rule before signing off on work, because many aircraft
equipped with ADS-B are operating with some type of unresolved problem," Marks said.
One way to make sure everything is good is to make
certain your installer uses ground-based testing
equipment. This equipment will detect most
issues, but the ultimate test is to fly an aircraft in
ADS-B rule airspace and request a performance
report. The FAA will provide a performance
report for free, usually within 30 minutes of
a flight. You can request your report at www.
adsbperformance.faa.gov/PAPRRequest.aspx.
The performance report will tell you what, if
anything, needs to be corrected. That will help
you figure out who needs to fix it. In most cases,
the answer is your avionics shop. ICAO codes
and Flight ID are set by the installer, and any
conflict between 1090/978 MHz outputs should
also be corrected by the installer.
An air/ground determination failure is more
complicated. Inspection by an installer is a good
first step, but the culprit could also be an issue
with the avionics. If the installer verifies that
This graphic generally depicts the airspace where ADS-B Out will be required by rule.
everything else is correct, you will need to go
For more information, visit www.faa.gov/nextgen/equipadsb/airspace.
to the equipment manufacturer. If this source is
unable to resolve the situation, please contact the
rule was first proposed, the idea was that aircraft would have
FAA via email at 9-AWA-AFS-300-ADSB-AvionicsCheck@
to equip with either a Mode S transponder (operating on 1090
faa.gov to request a review. This communication should include
MHz) or a Universal Access Transceiver or UAT (operating
"PAPR Review Request - Air/Ground Failure" in the subject
on 978 MHz). Both meet the requirement for an ADS-B transline, and you need to attach a copy of your performance report
mitter. To ensure that an aircraft is seen in all airspace - even
in the body of the message.
outside of FAA ADS-B coverage - some aircraft owners are
The FAA has prepared a user's guide to help operators
equipping with both device types. This approach can result in
understand what the ADS-B Performance Report means.
a "dual Out" problem.
The guide - available at www.adsbperformance.faa.gov/
"If the ICAO code in your Mode S transponder - reporting
PAPRUsersGuide.pdf - explains what each section of the report
to the ground on 1090 MHz - and your UAT avionics - reportis measuring. The performance report or the opportunity to gening on 978 MHz - are different, your aircraft may appear on a
erate one is a sound means to verify correct completion of the
controller's display as two aircraft in close proximity," Marks
installation work. q
30

avionics news

june

2017

http://adsbperformance.faa.gov/PAPRRequest.aspx http://adsbperformance.faa.gov/PAPRRequest.aspx http://www.faa.gov/nextgen/equipadsb/airspace http://adsbperformance.faa.gov/PAPRUsersGuide.pdf http://adsbperformance.faa.gov/PAPRUsersGuide.pdf

Table of Contents for the Digital Edition of Avionics News June 2017