Pilot's Guide to Avionics 2017-2018 - 45
controllers and nearby aircraft.
The FAA has seen an increasing number of
may see a second aircraft displayed very close to
your own position, prompting you to try to avoid an
reports about ADS-B and transponder ground tests
aircraft that isn't there. Mistakenly thinking you need
resulting in test signals being sent into surrounding
to act fast to avoid a collision with an aircraft that
airspace. This could prompt controllers to rapidly
doesn't exist can cause a safety hazard.
direct traffic around false targets or require pilots
The FAA ADS-B Focus Team's highest
to react to resolution advisories issued by TCAS
communications priority is to quickly contact any
equipment or to ADS-B In traffic alerts.
aircraft operator with incorrect ICAO codes (either
The recent increase in improper ground tests has
a single erroneous code or two codes that don't
prompted the FAA's ADS-B Focus Team to publish
match) or the wrong flight identification number. The
a Safety Alert for Operators to emphasize the
agency handles about 200 of these high-priority
importance of following applicable transponder and
cases a month.
ADS-B testing procedures. For more on this, visit
Because ADS-B performance problems can
emerge after initial installation, it is a good idea for
aircraft owners to check performance with PAPR
Aside from antenna-shielding issues, the FAA
says other high-priority ADS-B installation issues
periodically, especially after maintenance or a
software update to an ADS-B system component.
relate to improperly entered codes, including:
An aircraft's FAA-assigned ICAO 24-bit
code is wrong. Some ADS-B units are
requesting and receiving PAPR reports based
changed to the assigned aircraft code at
on feedback from aircraft owners, pilots and
installation or is entered incorrectly, the
An earlier process let users request ADS-B
FAA's ADS-B ground system. If an aircraft's
avionics performance by email, but responses could
N number can't be connected to a particular
take up to a day. Now a user can visit the FAA's
flight, a PAPR request cannot be processed.
portal an hour after a flight, enter data in a few
Two different ICAO codes might be loaded
fields and submit a request in a matter of minutes. A
in error into the Mode S transponder and the
six-page report comes back in about 30 minutes.
UAT on the same aircraft.
The FAA continues to improve the process for
manufactured with a default code. If it isn't
aircraft will not be properly recognized by the
Improving PAPR as ADS-B equipage rises
A PAPR provides an overall assessment of avionics
The flight identification number should match
performance and sufficient detail to determine if your
the aircraft call sign used in air traffic control
equipment complies with ADS-B regulations. It also
communications and the aircraft call sign
flags any issues about the integrity and accuracy of
filed on your flight plan.
your aircraft position reports.
If the transmitted ICAO code doesn't correlate
The FAA estimates that 100,000 to 160,000
to your aircraft's assigned N number, your ADS-B
general aviation aircraft may need to be ADS-B Out
installation is not compliant with the FAA rule.
equipped by the 2020 deadline. About 1,300 new
Ground test equipment will only verify that an ICAO
ADS-B installations occur each month.
code is loaded, not that it is valid for your airframe.
Having different codes in your Mode S
transponder and your UAT will appear on a
Equipping early and validating that your ADS-B
avionics are working properly will prevent any
potential headaches that could arise as the deadline
controller's display as two aircraft in close proximity.
If your aircraft is equipped with ADS-B In, you
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