Click on a question below to see the answer. If you have a question about this model that is not answered below, please contact sales@seaerospace.com
What is ADS-B?
Automatic Dependent Surveillance-Broadcast (ADS-B) is a component of the Next-Generation (Next Gen) Air Transportation System. ADS-B is an advanced surveillance technology that combines an aircraft’s positioning source (GPS), aircraft avionics, and a ground infrastructure to create an accurate surveillance interface between the aircraft & aircraft traffic control. ADS-B provides consistent position accuracy regardless of the aircraft’s range from the receiver.
The improved accuracy and update rate of ADS-B is a critical segment of the NextGen infrastructure.
The FAA has determined that it will be necessary for all aircraft operating in specific airspaces to be equipped with ADS-B Out by 2020. A nationwide infrastructure of ground stations is scheduled for completion during 2013.
As of June 2010, only ADS-B Out is being mandated. ADS-B Out provides the ATC with real-time position information. ADS-B In is the aircraft’s ability to receive and display other aircraft broadcasted information as well as the services provided by the ground stations.
ADS-B requires the use of a Positioning Source. As of June 2010, any positioning source is allowed; however, WAAS is the only positioning service that provides the equivalent availability required.
A Broadcast Link is also required for ADS-B functionality. There are two available options: 1090 MHz Extended Squitter (ES) or Universal Access Transceiver (UAT). FL 180 (the lower boundary of Class A airspace) is the ceiling for operating an aircraft equipped with UAT only.
ADS-B will eventually provide weather services, air traffic information, terrain maps and other flight information services for all pilots through satellite based data and ground stations. In accordance with NextGen, ADS-B will provide benefits that address some shortcomings over other, existing surveillance systems.
Some of these benefits include:
Air-to-air surveillance capability
Surveillance in remote areas where radar coverage is unavailable
Real-time traffic information for aircraft not equipped with active traffic systems (ex. TCAS, TAS)
Reduced separation between aircraft due to sharing of flight information between aircraft
Better predictability in departure and arrival times
Ultimately, ADS-B will allow aircraft to fly at safe distances from each another.
Click Here to View the official FAA NextGen Final Rule released on 5/28/10.
You may also View an SEA Summary of the FAA NextGen Final Rule (NOTE: this information has been altered for summary purposes and should be used as Reference Only).
Can the Trig TT21 and TT31, receive NMEA GPS data from any GPS receiver?
Yes, you can connect any NMEA GPS position source to a Trig transponder, and with the correct configuration the transponder will broadcast ADS-B position squitters. However there are limitations with the NMEA data. The NMEA messages do not include Receiver Autonomous Integrity Monitoring (RAIM) information, which means that the position transmitted by the Trig transponder will be indentified as "low quality" on most traffic information systems. Please note that this type of NMEA GPS/transponder configuration will not meet forthcoming FAA ADS-B requirements, but in the end it will be rather beneficial for use in flight tracking and traffic avoidance.
When I powered up my new TT21 transponder for the first time, I received the message "No remote link", then the unit went directly into "setup/test mode". Is this normal?
This is completely normal. The TT21, like most avionics units, needs to be setup and configured upon first use. The pilot’s guide and installation manual provided with the unit provides complete information for the setup and configuration process.
Do the Trig transponders offer Extended Squitter ADS-B out?
As of 2010, Trig TT22 & TT31 transponders include support for Extended Squitter (ES) ADS-B Out. The software in the Trig transponders for the ES ADS-B Out provide all of the required parameters listed in EASA AMC20-24. AMC20-24 is ADS-B airworthiness approval for EASA. This "Acceptable Means of Compliance" spells out the performance requirements of such equipment.
In order to utilize the ADS functions of the Trig transponders, a GPS receiver meeting specific criteria must be interfaced with the transponder. As of 2010, the Freeflight 1201 and NexNav 3101 are the only GPS receivers that can be used with the Trig transponders for this function.
Please visit www.seaerospace.com for continuous updates on the ADS-B discussion and added features to the Trig transponders.
Do the Trig transponders offer TIS traffic?
Yes. A Trig software upgrade adds TIS (Traffic Information Service) functionality to any TT21 or TT31 transponder. The traffic upgrade is compatible with any Garmin 396/495/496/695/696 GPS for display of TIS traffic information.
The TIS feature has been ground tested and real-time flight tested by Trig Avionics and Southeast Aerospace personnel.
All new Trig transponders, including TT21, TT22 & TT31, will ship with most recent software already incorporated.
Does SEA offer Shop or Dealer pricing for the Trig TT21 and TT21 transponders?
Yes, Southeast Aerospace offers a flat Shop price and Dealer Quantity Price discounts for both the TT21 and TT22 transponders. Please contact SEA Sales Supervisor, Aprile Blair, for detailed information.
How do I enter my Mode S address into the Trig transponder?
The Mode S Address is a 24 bit number issued to the aircraft by the registration authority for the aircraft. These addresses are usually written as a 6 digit hexadecimal number. You may encounter the address written as an 8 digit octal number as is the case with the FAA aircraft registration website. The Trig TT21, TT22, and TT31 only accept the hexadecimal format. To convert from octal to hex code, you can utilize the Calculator in the Microsoft Accessories folder. Or, there are many online tools to accomplish the conversion as well.
Southeast Aerospace can answer any questions or inquiries relating to the programming of the Trig transponders. Please contact us for assistance.
I need a basic transponder antenna, which one should I buy?
Although some manufacturers call out specific transponder antennas in their installation manuals, almost any transponder antenna can be used with any transponder. Various models are available based on the screw hole pattern desired and the speed & drag considerations based on the aircraft type.
AV-22
CI-101
For smaller general aviation aircraft, Southeast Aerospace recommends the stub type AV-22 or CI-101 antenna.
CI-105
AV-74
For medium to larger aircraft, Southeast Aerospace recommends the blade type CI-105 or AV-74 antenna.
Ultimately, it is the responsibility of the installer or installing agency to determine what antenna is suitable for the aircraft application.
Do the Trig Transponders meet the current ADS-B requirements as stated in the FAA Final Rule released in May 2010?
As of June 2010, the Trig Transponders do not currently meet the FAA's recently updated requirements.
However, in the near future Trig will be releasing several firmware updates for their ADS-B Transponders.
More information will be provided as soon as it becomes available. Transponder issues will be addressed as the FAA ADS-B requirements become more developed.
Southeast Aerospace & Trig Avionics will continue to be vigilant in notifying our customers of ADS-B requirements and solutions as soon as they become available. Customers can be assured that these solutions will be available well before the ADS-B requirements deadline.
What transponder can I use to replace my Terra TRT-250/TRT-250D?
Trig's TT22 Mode S Transponder is an ideal TRT-250/250D replacement. The TT22 compact head design is capable of fitting in the small cutout left by the Terra transponder. Note that a new wiring harness will be needed.
What is the installation procedure for a Trig TT21 or TT22 transponder?
An FAA Form 337 or STC is not required for a TT21/22 transponder installation.
To install a TT21/31 you must have the proper equipment & complete a log book entry noting the installation.
I have my Trig transponder installed & am receiving a signal; however I now hear a "ticking" noise on my radio. What could this be?
The transponder transmissions are causing interference. The most likely reason for this is that your aircraft is not grounded and you have unshielded wiring. Just a small piece of unshielded wiring could cause this problem.
There are two ways to stop the ticking. First off you can create a grounded plane. However, this isn't an ideal solution, since you still have a wiring problem.
The second solution is to find the exposed wire & correct the problem. You should test to find the wire by using only one piece of equipment at a time - if you have 2 radios, listen to each one individually, etc. Next check your headset & your aircraft power wiring. A good way to test your wires for shielding is to wrap aluminum foil on different sections of wiring while trouble shooting.
TT21 Product FAQ
Click on a question below to see the answer. If you have a question about this model that is not answered below,
please contact sales@seaerospace.com
What is ADS-B?
Automatic Dependent Surveillance-Broadcast (ADS-B) is a component of the Next-Generation (Next Gen) Air Transportation System. ADS-B is an advanced surveillance technology that combines an aircraft’s positioning source (GPS), aircraft avionics, and a ground infrastructure to create an accurate surveillance interface between the aircraft & aircraft traffic control. ADS-B provides consistent position accuracy regardless of the aircraft’s range from the receiver.
The improved accuracy and update rate of ADS-B is a critical segment of the NextGen infrastructure.
The FAA has determined that it will be necessary for all aircraft operating in specific airspaces to be equipped with ADS-B Out by 2020. A nationwide infrastructure of ground stations is scheduled for completion during 2013.
As of June 2010, only ADS-B Out is being mandated. ADS-B Out provides the ATC with real-time position information. ADS-B In is the aircraft’s ability to receive and display other aircraft broadcasted information as well as the services provided by the ground stations.
ADS-B requires the use of a Positioning Source. As of June 2010, any positioning source is allowed; however, WAAS is the only positioning service that provides the equivalent availability required.
A Broadcast Link is also required for ADS-B functionality. There are two available options: 1090 MHz Extended Squitter (ES) or Universal Access Transceiver (UAT). FL 180 (the lower boundary of Class A airspace) is the ceiling for operating an aircraft equipped with UAT only.
ADS-B will eventually provide weather services, air traffic information, terrain maps and other flight information services for all pilots through satellite based data and ground stations. In accordance with NextGen, ADS-B will provide benefits that address some shortcomings over other, existing surveillance systems.
Some of these benefits include:
Air-to-air surveillance capability
Surveillance in remote areas where radar coverage is unavailable
Real-time traffic information for aircraft not equipped with active traffic systems (ex. TCAS, TAS)
Reduced separation between aircraft due to sharing of flight information between aircraft
Better predictability in departure and arrival times
Ultimately, ADS-B will allow aircraft to fly at safe distances from each another.
Click Here to View the official FAA NextGen Final Rule released on 5/28/10.
You may also View an SEA Summary of the FAA NextGen Final Rule (NOTE: this information has been altered for summary purposes and should be used as Reference Only).
Can the Trig TT21 and TT31, receive NMEA GPS data from any GPS receiver?
Yes, you can connect any NMEA GPS position source to a Trig transponder, and with the correct configuration the transponder will broadcast ADS-B position squitters. However there are limitations with the NMEA data. The NMEA messages do not include Receiver Autonomous Integrity Monitoring (RAIM) information, which means that the position transmitted by the Trig transponder will be indentified as "low quality" on most traffic information systems. Please note that this type of NMEA GPS/transponder configuration will not meet forthcoming FAA ADS-B requirements, but in the end it will be rather beneficial for use in flight tracking and traffic avoidance.
When I powered up my new TT21 transponder for the first time, I received the message "No remote link", then the unit went directly into "setup/test mode". Is this normal?
This is completely normal. The TT21, like most avionics units, needs to be setup and configured upon first use. The pilot’s guide and installation manual provided with the unit provides complete information for the setup and configuration process.
Do the Trig transponders offer Extended Squitter ADS-B out?
As of 2010, Trig TT22 & TT31 transponders include support for Extended Squitter (ES) ADS-B Out. The software in the Trig transponders for the ES ADS-B Out provide all of the required parameters listed in EASA AMC20-24. AMC20-24 is ADS-B airworthiness approval for EASA. This "Acceptable Means of Compliance" spells out the performance requirements of such equipment.
In order to utilize the ADS functions of the Trig transponders, a GPS receiver meeting specific criteria must be interfaced with the transponder. As of 2010, the Freeflight 1201 and NexNav 3101 are the only GPS receivers that can be used with the Trig transponders for this function.
Please visit www.seaerospace.com for continuous updates on the ADS-B discussion and added features to the Trig transponders.
Do the Trig transponders offer TIS traffic?
Yes. A Trig software upgrade adds TIS (Traffic Information Service) functionality to any TT21 or TT31 transponder. The traffic upgrade is compatible with any Garmin 396/495/496/695/696 GPS for display of TIS traffic information.
The TIS feature has been ground tested and real-time flight tested by Trig Avionics and Southeast Aerospace personnel.
All new Trig transponders, including TT21, TT22 & TT31, will ship with most recent software already incorporated.
Does SEA offer Shop or Dealer pricing for the Trig TT21 and TT21 transponders?
Yes, Southeast Aerospace offers a flat Shop price and Dealer Quantity Price discounts for both the TT21 and TT22 transponders. Please contact SEA Sales Supervisor, Aprile Blair, for detailed information.
How do I enter my Mode S address into the Trig transponder?
The Mode S Address is a 24 bit number issued to the aircraft by the registration authority for the aircraft. These addresses are usually written as a 6 digit hexadecimal number. You may encounter the address written as an 8 digit octal number as is the case with the FAA aircraft registration website. The Trig TT21, TT22, and TT31 only accept the hexadecimal format. To convert from octal to hex code, you can utilize the Calculator in the Microsoft Accessories folder. Or, there are many online tools to accomplish the conversion as well.
Southeast Aerospace can answer any questions or inquiries relating to the programming of the Trig transponders. Please contact us for assistance.
I need a basic transponder antenna, which one should I buy?
Although some manufacturers call out specific transponder antennas in their installation manuals, almost any transponder antenna can be used with any transponder. Various models are available based on the screw hole pattern desired and the speed & drag considerations based on the aircraft type.
AV-22
CI-101
For smaller general aviation aircraft, Southeast Aerospace recommends the stub type AV-22 or CI-101 antenna.
CI-105
AV-74
For medium to larger aircraft, Southeast Aerospace recommends the blade type CI-105 or AV-74 antenna.
Ultimately, it is the responsibility of the installer or installing agency to determine what antenna is suitable for the aircraft application.
Do the Trig Transponders meet the current ADS-B requirements as stated in the FAA Final Rule released in May 2010?
As of June 2010, the Trig Transponders do not currently meet the FAA's recently updated requirements.
However, in the near future Trig will be releasing several firmware updates for their ADS-B Transponders.
More information will be provided as soon as it becomes available. Transponder issues will be addressed as the FAA ADS-B requirements become more developed.
Southeast Aerospace & Trig Avionics will continue to be vigilant in notifying our customers of ADS-B requirements and solutions as soon as they become available. Customers can be assured that these solutions will be available well before the ADS-B requirements deadline.
What transponder can I use to replace my Terra TRT-250/TRT-250D?
Trig's TT22 Mode S Transponder is an ideal TRT-250/250D replacement. The TT22 compact head design is capable of fitting in the small cutout left by the Terra transponder. Note that a new wiring harness will be needed.
What is the installation procedure for a Trig TT21 or TT22 transponder?
An FAA Form 337 or STC is not required for a TT21/22 transponder installation.
To install a TT21/31 you must have the proper equipment & complete a log book entry noting the installation.
I have my Trig transponder installed & am receiving a signal; however I now hear a "ticking" noise on my radio. What could this be?
The transponder transmissions are causing interference. The most likely reason for this is that your aircraft is not grounded and you have unshielded wiring. Just a small piece of unshielded wiring could cause this problem.
There are two ways to stop the ticking. First off you can create a grounded plane. However, this isn't an ideal solution, since you still have a wiring problem.
The second solution is to find the exposed wire & correct the problem. You should test to find the wire by using only one piece of equipment at a time - if you have 2 radios, listen to each one individually, etc. Next check your headset & your aircraft power wiring. A good way to test your wires for shielding is to wrap aluminum foil on different sections of wiring while trouble shooting.
REPAIR
No repair or service price information available for this item online. Please contact our Service Department for a Repair Quote on this item.
Item is not available for over-the-counter(OTC) sale and must be installed by Southeast Aerospace.
If you are interested in an installation quotation, please click here.
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