air avionics AIR Traffic Manual

air avionics
AIR Trac
Pilot’s Manual
Document: MAN0070A0002
Version: 4.0
Date: 2020/01/09
Phone: [phone] ·Fax: [phone]
Internet: https://www.air-avionics.com ·Mail: [email protected]

air avionics
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Important
Please read this manual carefully before using the device.
Observe limitations and safety instructions.
This manual is an essential portion of the device and must be kept in a safe place.
Articles Covered
This manual covers the following articles:
•AT-1 ‘‘AIR Trac’’, software version 5 and later.
Revision History
Rev. Date Status Author Changes Approved
1.0 2018/08/29 Release M. Förderer Initial release H. Hoeth
2.0 2018/10/25 Release M. Förderer Secondrelease,variousfunctionsadded. –
2.1 2018/12/21 Release M. Förderer Added details regarding ARINC429 be-
havior while not moving. –
3.0 2019/05/20 Release M. Förderer Added informations regarding the latest
software version 5. –
4.0 2020/01/09 Release M. Förderer Added informations regarding the latest
software versions 7 and 8. –
Product Support
If you have questions, our product support team will be happy to help you. Contact us
via [email protected] or by phone. Please nd details about our hotlines and
availability online at https://www.air-avionics.com
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Contents
Getting Started ·1
Introduction ·1
Safety Instructions and Limitations ·2
Switching On and O ·3
General Theory of Operation ·4
ADS-B In ·4
Replies by 1090 MHz Mode-S Transponders ·4
FLARM ·5
GPS ·5
Collision Warnings ·6
Displaying Trac Information ·8
Dedicated Cockpit Displays of Trac Information ·8
Navigation and Electronic Flight Information Systems ·9
Wireless Connectivity to Tablets and Smartphones ·10
Audio Output and Discrete Switches ·12
Audio Output ·12
Discrete Switches ·14
Flight Recording and Post Flight Analysis ·15
Flight Recording ·15
Flight Data Readout ·15
Post Flight Analysis ·15
Software and Database Updates ·16
Version Identication ·16
Software/Database Loading ·16
System Status ·18
Status LEDs ·18
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Contents
Troubleshooting ·24
My AT-1 does not seem to power up. ·24
I am unable to connect via WiFi, the network is not visible. ·24
Bibliography ·25
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Contents
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Getting Started 1
1.1 Introduction
The AIR Trac (AT-1) by AIR Avionics is a trac/electronic conspicuity system based on
1090 MHz receiving and FLARM transceiving technology.
AT-1 uses 1090 MHz Mode-S transponder replies
1
, 1090 MHz ADS-B broadcasts, and FLARM
broadcasts to determine positions, ight vectors, and threat levels of other air trac. AT-1
broadcasts the own ship’s GPS position via FLARM to other FLARM equipped aircraft or
ground stations.
Additionally AT-1 covers other functions such as obstacle warnings, alert zone warnings,
and ight trajectory logging.
AT-1 is installed remotely. It interfaces to many avionics systems via a wide range of
standardized wire-connected and wireless interfaces. These avionics systems (e.g. cockpit
displays of trac information, electronic ight information systems, or handheld navigators)
display the information AT-1 provides.
As to date, there are no minimum performance specications or technical standard orders
for such trac systems, AT-1 is not certied against an ETSO or TSO standard. Nevertheless,
it is developed in accordance with aviation standards and meets aviation performance
specications. It can be installed into many aircraft using Supplementary Type Certicates
(STC), Minor Change Approvals (MCA), or Standard Change Approvals under CS-STAN.
Device Label
Connector 2 (D-SUB 15HD)
Connector 1 (D-SUB 26HD)
3 Status LED
Static Port
USB Connector
GPS Antenna Connector (QMA)
1090MHz Antenna Connector (rpSMA)
FLARM Antenna Connector A (SMA) FLARM Antenna Connector B (SMA)
WiFi Antenna
Figure 1.1.: AT-1 hardware overview
1AT-1 does not actively interrogate transponders
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1. Getting Started
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1.2 Safety Instructions and Limitations
1.2.1 Safety
AT-1 shall never distract from general practices of safe airmanship. Using AT-1 may impose
signicant workload on the ight crew if not adequately familiar with AT-1 and trained on
its use. In order to use AT-1 eectively, familiarization with the unit’s capabilities, limitations,
and mode of operation is essential.
We recommend a thorough study of this manual and extensive familiarization on the
ground.
Do not y with AT-1 if you are unfamiliar with its use and limitations
Installations in which AT-1 devices are used may be complex. Familiarization of specic
installation conditions in an aircraft, for example the number, type, and conguration of
connected systems is essential before using AT-1.
AT-1 installations require several forms such as checkout forms and conguration logs
to be lled out by installation personnel. These documents are stored in the aircraft’s
documentation and are a viable resource for pilots who wish to study installation specics
of an AT-1 in an aircraft.
1.2.2 Regulatory Requirements
It is the responsibility of those installing and using this article to determine that the
installation and working conditions are within required standards.
1.2.3 Screen Shots
All screen shots used in this document are current at the time of publication.
Screen shots are intended to provide visual reference only. All information depicted in
screen shots, including software le names, versions, and part numbers, is subject to change
and may not be up to date.
1.2.4 Function Licensing and Software Expiry
Some software features such as FLARM functionality or obstacle databases have expiration
dates and may become unavailable as they expire. Validity is checked regularly. After
the FLARM software has expired, major functions become unusable until the software is
updated.
Ensure that the installed software version is always valid and up to date. Failure to
update the unit regularly will result in reduced functionality and system failures!
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1. Getting Started
1.2.5 Liability
IN NO EVENT WILL AIR AVIONICS BE LIABLE FOR ANY INCIDENTAL, SPECIAL, INDIRECT OR
CONSEQUENTIAL DAMAGES, WHETHER RESULTING FROM THE USE, MISUSE OR INABILITY
TO USE THE PRODUCT OR FROM DEFECTS IN THE PRODUCT.
1.2.6 Limitations
AT-1 is subject to various limitations.
AT-1 does not protect the aircraft from collisions with other air trac or obstacles. It
only serves as an aid to the ight crew and intends to help recognizing threats and thus
increasing situational awareness.
AT-1 is not capable of detecting the entire air trac and all obstacles that may obstruct the
aircraft’s ight path. Only a fraction of the air trac and a fraction of obstacles in some
areas of the world can be detected.
AT-1 does not work all the time. Certain requirements need to be met for AT-1 to work
properly. Examples are up-to-date software or the correct installation of AT-1, its antennas,
and connected systems.
Errors and failures in the device may occur. It is possible that AT-1 fails during operation. It
is possible that AT-1 shows misleading and/or wrong information to connected cockpit
systems and/or to other aircraft. Never absolutely rely on data given by AT-1.
Do not make safety critical decisions based on data from AT-1 alone.
1.3 Switching On and O
1.3.1 Power On
Depending on its installation, AT-1 either switches on automatically if sucient supply
power is present, or is switched on by a connected system, such as a compatible cockpit
display of trac information.
AT-1 requires at least 9V DC to switch on. Booting AT-1 normally takes less than one minute.
Please note that depending on the unit’s installation and connected systems it may take
longer than one minute until full functionality is available.
1.3.2 Power O
AT-1 is either powered o by a connected system, or by taking away supply power. AT-1 can
always be safely switched o by taking away supply power.
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2General Theory of Operation
2.1 ADS-B In
The AT-1 ADS-B In capability allows it to receive trac data through a built in 1090 MHz
Extended Squitter (1090 ES) receiver.
Automatic Dependent Surveillance - Broadcast (ADS-B) is the automatic broadcast of
position reports by aircraft, surface vehicles, and transmitters on xed objects. These
broadcasts contain much more data than just a simple position report, they include: identity
(Flight ID/Tail Number, ICAO registration number, etc), ground track, ground speed, pressure
altitude, indications of equipment capabilities, and emergency status.
AT-1 processes all received ADS-B messages, also those from equipment with no source
integrity or design assurance levels (SIL=0, SDA=0). Therefore, it is also processing
information from ADS-B transmitters with non-certied GPS data sources.
2.2 Replies by 1090 MHz Mode-S Transponders
AT-1 receives and processes replies sent by Mode-S transponders on the 1090 MHz
transponder frequency band.
As AT-1 does not actively interrogate transponders, it is unable to trigger transponder replies
itself. Transponders have to be interrogated by radar stations or active trac systems in
order to transmit such replies that the AT-1 can receive. Additionally, the received replies
must contain altitude reports in order to be processed by AT-1. Transponder replies without
encoded altitude levels are not processed.
Mode-S transponder replies do not contain position reports. Therefore, AT-1 is not capable
of determining the exact position of the replying target. It estimates the target’s distance
using the eld strength of the received signal. These estimations have very limited precision.
Moreover AT-1 determines the target’s precise level and vertical rate by using the altitude
encoded into the transponder reply. Vertical separation is determined using barometric
data from the integrated barometric sensor in the AT-1.
Targets detected using this method are commonly referred to as ‘‘bearingless targets’’, as
their relative bearing is unknown.
The relative bearing (direction) of targets solely detected via Mode-S transponder
replies is unknown and can not be shown to the ight crew.
Mode-A and Mode-C transponder replies are not processed.
While AT-1 can process multiple bearingless targets, most cockpit displays only show the
single most relevant bearingless target to the ight crew in order to minimize confusion
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2. General Theory of Operation
and user interface clutter. Some cockpit displays only show information about the most
relevant bearingless target if a collision threat is detected and a warning is given to the
ight crew. Some display systems only display bearingless targets as a numerical value, for
example: 5 miles / +500ft.
own ship symbol
Traffic target with bearing
and altitude (3D position)
-02
+05
Bearingless traffic target,
only distance and altitude
known. The target can be
anywhere on the dotted
circle.
Figure 2.1.: Illustration of a trac target shown in a 3D position and a bearingless trac
target.
2.3 FLARM
Based on GPS and a pressure sensor, FLARM predicts the short-term future ight path and
continuously broadcasts this to nearby aircraft by means of a digital radio message. FLARM
systems in nearby aircraft receive the radio message and return a similar message with the
same set of data.
FLARM data is sent by aircraft, surface vehicles, or xed obstacles. FLARM broadcasts
contain GPS data, identity, altitude, and several status ags.
Practical experience shows that ADS-B does not provide suciently precise data to warn
about aircraft conducting aerial work or glider trac with its frequent altitude changes and
steep turns. To ensure high alert quality, AT-1 does not use ADS-B data to compute alerts
for targets which also broadcast FLARM data. Instead, it will exclusively rely on the target’s
more precise FLARM data.
2.4 GPS
AT-1 detects the own ship’s 3D position using GPS. The GPS receiver used in AT-1 is an
industry standard COTS GPS receiver. While the GPS receiver delivers high accuracy, low
power consumption, and quick start times, the position integrity is unknown to AT-1. Please
be aware that misleading information failure modes are possible. This means that the GPS
position used may be wrong or of low accuracy without notice to the ight crew.
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2. General Theory of Operation
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2.5 Collision Warnings
2.5.1 Normal Collision Warnings
AT-1 is able to calculate conicting ight patterns and to issue collision warnings. AT-1
warns about obstacles on the ground (cables, masts, etc.) if a current obstacle database is
installed.
Collision warnings are issued depending on the time remaining to a potential collision
(time to ipact), not the geometric distance between aircraft. Warnings are selective, that
means they are only issued if the calculation detects a high probability of a collision.
!
235kt
100kt
110kt
Figure 2.2.: Example of a conicting trac situation. Two closely ying aircraft do not cause
a collision warning from each other, as their trajectories are not estimated to
produce a conict. The trajectory of a third aircraft, that is farther away, however,
will be conicting, therefore a collision warning is issued.
Warnings are issued with dierent threat levels depending on their severity. In trac
displays and the audio output, dierent threat levels are reproduced dierently in order to
inform the ight crew about the threat level and urgency of the warning.
1. The rst warning is typically issued between 19 and 25 seconds before the calculated
potential collision with an aircraft or an obstacle (time to impact).
2. The second warning is issued 14 to 18 seconds in advance.
3. The third warning 6 to 8 seconds in advance.
Warnings are sustained as long as the threat remains. Depending on changes in the
prediction, the threat level is downgraded or the warning is ceased entirely.
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2. General Theory of Operation
2.5.2 Protection Volumes
In addition to calculated threat levels, several ‘‘protection volumes’’ can be dened in the
system conguration of the AT-1. Up to four dierent volumes can be congured, each of
which has dierent priorities.
If a target enters a protection volume, a predened threat level is assigned to this target,
independent from its calculated threat level and, therefore, also independent from the
estimated time to impact. Protection volume horizontal and vertical sizes as well as their
threat levels can be selected freely by the installer.
In the default setup, only one protection volume is congured in a rather small size.
We strongly recommend this setting as the calculated trac warnings based on ight
patterns are way better for almost any standard application. Multiple protection
volumes are only used in very special applications like towing banners/drones/probes
or in helicopters who regularly perform winching operations.
Depending on the protection volume setup, AT-1 may stop working entirely, stop to
provide collision warnings, or issue nuisance alarms. Do never change the respective
conguration parameters unless you know exactly what you are doing and why.
!
!
Outer protection volume
Inner protection volume
Figure 2.3.: Example of a setup with four protection volumes. A threat level is adssigned to
the target inside of protection volume 1 (white background) although it would
not receive a threat level based on its ight pattern (no collision course).
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3Displaying Trac Information
At least one cockpit system displaying trac is required. AT-1 allows to connect multiple
trac displays simultaneously.
Trac displays typically show a two-dimensional (top-down) view of trac that is detected
by the AT-1 system. Target position, bearing, distance, relative altitude, and vertical trend
can be depicted on the trac display, depending on type of display and target data
availability.
3.1 Dedicated Cockpit Displays of Trac Information
AT-1 is compatible to a broad range of dedicated cockpit displays of trac information
(CDTI).
Depending on the type and capabilities of the used CDTI, not all functions of AT-1
may be supported. Please refer to the CDTI’s documentation for details.
While many navigation systems or electronic ight information systems display trac
information and warnings, it is recommended to use at least one dedicated CDTI. Experience
and human factors research have shown that using a dedicated CDTI improves the trac
situational awareness of the ight crew compared to integrated multi-function systems
alone.
AT-1 has been designed to work with the AIR Avionics AIR Trac Display line of products
(ATD-XX). AIR Trac Displays oer comprehensive functionality and amongst others are
capable of conguring the system conguration parameters of the AT-1.
Figure 3.1.: The AIR Trac Display product family as an example for cockpit displays of
trac information (CDTI).
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3. Displaying Trac Information
The data interfaces from the AT-1 to the CDTI are congured during the installation
process. For detailed information on available interfaces, compatible CDTI systems, and
their conguration, please consult the AT-1 Installation Manual [1].
3.2 Navigation and Electronic Flight Information Systems
AT-1 is compatible to most navigation systems (portable and panel mount) and electronic
ight information systems (EFIS).
Depending on the type and capabilities of the used EFIS, not all functions of AT-1
may be supported. Please refer to the EFIS documentation for details. Some EFIS
systems do not support AT-1 status display. If only using an EFIS system to display
trac, please ensure AT-1 operates correctly, for example by monitoring the unit’s
status LED.
Some EFIS systems are not capable of displaying bearingless targets at all, some are
not capable of displaying other targets while a bearingless target is displayed.
The data interfaces from the AT-1 to the EFIS system are congured during the installation
process. For detailed information on available interfaces, compatible EFIS, and their
conguration, please consult the AT-1 Installation Manual [1].
3.2.1 Special behavior of EFIS systems requiring an aircraft heading to
show trac targets
Some EFIS systems and some data interfaces require a current heading to be transmitted
by the AT-1 to display trac targets. This especially applies to all EFIS systems that use the
ARINC429 data interface like, for example, GARMIN GTN or GNS.
Without a movement of the own aircraft, the AT-1 is unable to determine the own
aircraft’s current heading.
Therefore, while sitting on the ground or while hovering with groundspeed zero, only the
closest trac target is shown. This target is shown as a bearingless target (distance and
vertical separation only, no bearing).
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3. Displaying Trac Information
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own aircraft is moving,
own heading available
Other traffic target
with bearing and
altitude (3D position)
+05
+05
own aircraft is not moving,
own heading not available
?
Other traffic target , bearingless,
only distance and altitude known
Figure 3.2.: Left: A trac target is shown as a 3D position when aircraft movement is present
and, therefore, the own aircraft heading is known. Right: Aircraft does not move,
the own aircraft heading is unknown, therefore, a trac target is shown as a
bearingless target (distance and altitude only). Some EFIS systems only display
bearingless targets as a numerical value, for example: 5 miles / +500ft.
Depending on the AT-1 system conguration, the output of trac target data can be
suppressed without movement. In this case, if no trac data is transmitted over the
ARINC429 interface the trac interface status "STANDBY" is shown on the EFIS system.
3.3 Wireless Connectivity to Tablets and Smartphones
AT-1 has an integrated WiFi Interface. This interface allows the direct connection of devices
with WiFi capabilities such as personal computers, smartphones or tablets (in this manual,
these are referred to as ‘‘personal devices’’).
The AT-1 can be congured over the AT-1 conguration webpage via WiFi. For details, please consult
the AT-1 Installation Manual [1].
AT-1 oers an in-ight WiFi data connection that is compatible with a wide range of aviation
apps and allows these apps to display trac data from the AT-1. In addition to trac
information and warnings, AT-1 also shares the current GPS position and the accurate
barometric altitude with connected apps.
3.3.1 List of Tested Apps
The following Apps have been tested and are considered compatible with AT-1. Other Apps
may be compatible as well. If you are using an app not covered in the list below, please
consult the app manufacturer for details on compatibility.
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3. Displaying Trac Information
App Make Remarks
iGlide/iPilot AIR Avionics –
SkyDemon SkyDemon –
AirNav Pro XAMPLE –
Runways HD AIRBOX –
SkyMap SkyMap –
FlyMap Stau –
EasyVFR PocketFMS –
Foreight FOREFLIGHT Please select the GDL90 data protocol
3.3.2 Establishing a Connection
In order to establish a wireless network connection with the AT-1, please follow these steps:
1. Open the WiFi conguration page in your personal device. Normally you can nd
this page in the settings/system preferences app of your personal device.
2. SelecttheAIRTracWiFinetworkandestablishaconnection. Thenetworkname/SSID
will be ‘‘AIR-Trac-’’ followed by the last two digits of the serial number of the AT-1.
3. Enter the network password. The password is the full serial number as printed below
the bar code on the sticker on the device, for example AT1-00003.
If establishing a connection is not possible, please ensure the WiFi interface in AT-1 has been activated
during installation. Depending on its setup, the WiFi interface might only work for 15 minutes after
power-on. In this case, please open the AT-1 conguration webpage directly after switching the
device on and change the setup for the WiFi interface to be permanently active. For details, please
consult the AT-1 installation manual [1].
P/N: AT-1-(00000)
ADS-B 1090-in, Flarm 868/915 MHz in/out
RTCA DO-160G:
D1ZBAB[UFF1]XXXXXXZBBBAC[TT]M[A2XXX]XXAX
9-32 V DC
*AT1-00003*
Figure 3.3.: AT-1 serial number sticker
3.3.3 Using Data in an App
In order to use data from the AT-1 in an app, in most cases the connection has to be activated
in the app. For details, please consult the app’s documentation.
Please ensure that the AT-1 WiFi interface has been congured to the correct data protocol.
The factory setting (FLARM protocol) works for all apps besides FOREFLIGHT. If using
FOREFLIGHT, please in the AT-1 conguration webpage, set the protocol for the WiFi
Interface to ‘‘GDL90’’.
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4Audio Output and Discrete Switches
4.1 Audio Output
AT-1 features an audio output that can be interfaced to the aircraft’s audio system. The
audio output can be set up to generate beep tones or voice messages.
Before using AT-1 in combination with a connected audio interface, please familiarize
yourself with the installation conditions. For detailed informations on the interface, wiring,
and compatibility, please consult the AT-1 Installation Manual [1].
4.1.1 Beep Tones
The audio output generates beep tones with a base frequency of 3300Hz. The intensity of
the beeps is increased if a trac or obstacle warning becomes more urgent. The following
table describes which tones are generated:
Situation Beep Pattern
Shortly after device power-on Short single test beep (1s)
Info Alert (Aircraft is received for the rst time) Short single beep (0,15s)
Warning (target lower than own aircraft) Double beep (normal beep followed
by lower frequency beep)
Warning (target higher than own aircraft) Double beep (normal beep followed
by higher frequency beep)
4.1.2 Voice Messages
The voice output generates spoken messages with a natural male voice. The following
table describes which messages are generated:
Situation Message Example
Device power-on AIR Trac + SOFTWAREVERSION ‘‘AIR TRAFFIC SIX’’
Warning TONE + DIRECTION + AZIMUTH + TARGET BEEP ‘‘10 O’CLOCK ABOVE GLIDER’’
Urgent Warning TONE + DIRECTION + AZIMUTH WOOTWOOT ‘‘10 O’CLOCK ABOVE’’
System message COMPONENT + STATUS ‘‘GPS FAULT’’
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4. Audio Output and Discrete Switches
10 O'Clock
11 O'Clock
9 O'Clock
8 O'Clock
HIGH
LOW
ABOVE
BELOW
-14°
-45°
14°
45°
7 O'Clock
6 O'Clock
5 O'Clock
4 O'Clock
3 O'Clock
2 O'Clock
1 O'Clock
AHEAD
Figure 4.1.: Direction and azimuth indications in voice warning messages.
Voice messages can be acknowledged by pushing an optional VOICE ACK button, or by
pushing the inner knob pushbutton on a connected AIR Trac Display (ATD).
When acknowledging a trac or obstacle warning message, all voice warning messages,
generated by the specic target, are supressed for ve minutes.
Up to 10 system voice messages can be acknowledged once and will then be suppressed
until the AT-1 is restarted.
4.1.3 Volume Control
The volume of the AT-1 audio output is typically controlled in the aircraft’s audio panel. In
this case the output volume is pre-adjusted once in the AT-1 system conguration during
installation and is then controlled in-ight via the aircraft audio panel’s controls.
The output volume can also be controlled by means of an external volume control rotary
knob that is directly connected to the AT-1. When adjusting the volume by using this knob,
an info beep indicating the current volume is played while turning the knob.
Please consult the aircraft’s documentation for details on the specic installation.
Audio messages can be very distracting to the ight crew and signicantly increase
crew workload. Always familiarize yourself with the specic installation conditions
and ensure the volume level is appropriate before each ight.
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4. Audio Output and Discrete Switches
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4.2 Discrete Switches
AT-1 features discrete inputs that can optionally be used together with switches/buttons in
the airframe or panel. Depending on the specic installation, the following functions can
be triggered using switches:
•MUTE – The AT-1 audio output can be muted.
•
NO ALARMS – Trac warnings issued over the AT-1 data interfaces can be suppressed.
•ON GND – In this case, the switch sets the aircraft’s ight state as on-the-ground.
•
APPROACH MODE – In approach mode, the warning sensitivity is reduced. This mode
can be used during IFR approaches or during formation ying.
•
VOICE ACK – Acknowledges a voice message for 5 minutes, e.g. a trac warning from
a specic trac target.
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