How does the Trig TT31 compare to the Bendix/King KT-76C?
The Trig TT31 Mode S Transponder is a cost-effective replacement for the Bendix/King KT-76C, especially since it is a direct replacement for KT-76A, KT-78A and KT-76C transponders with no installation changes.
For quick reference, please review the outline comparison of the KT-76C vs. TT31:
FEATURE
KT-76C
TT31
ADS-B Capable
No
Yes, 1090ES
Altitude Monitor
No
Yes
Current Draw (14V)
1.6 Amps
.63 Amps
Flight ID Display
No
Yes
GPS Input
No
Yes
Mode S
No
Yes, Level 2
Power
200 watts
240 watts
Solid State
No, PA Tube
Yes
Timer
No
Yes
TSO
C74c
C112
Warranty
2 Years
2 Years
Weight
2.4 lbs.
2.8 lbs.
Should a new transponder certification be performed if simply replacing an existing transponder?
Yes, anytime a transponder is removed or replaced an altitude correlation between what the transponder is reporting and what is displayed on the altimeter needs to be performed. This is outlined in FAA CFR Part 91.413. This regulation indicates that following any installation or maintenance of a transponder where data correspondence error could be introduced, the integrated system has been tested, inspected, and found to comply with paragraph (c), appendix E. Furthermore, these references indicate that an integration test between the altitude reporting equipment and transponder system must be conducted.
For complete information, please refer to these FAA regulations or contact Southeast Aerospace Tech Support team at shop@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).
Why is the KT-79 not an ideal choice for a new transponder installation?
The KT-79 is a basic digital Mode C transponder. Due to its age, components for the transmitter assembly are no longer available from Honeywell. Therefore, due to inevitable reliability and warranty issues, the KT-79 is not an ideal choice for a transponder installation. SEA offers many transponders available in the same price range with more features to consider.
SEA suggests the Trig TT31. The TT31 is a Mode S level 2 datalink transponder with extended squitter, which also supports growing ADS-B technology, available in the same price range as the KT-79.
KT-79
Trig TT31
Does Southeast Aerospace offer "Shop" pricing for the TT31 Mode S Transponder?
Yes, SEA does offer a "shop" price for the TT31 to certified repair stations that meet the following criteria:
Per FAA Part 91.413 (ATC transponder tests and inspections), after any installation or maintenance on an ATC transponder, the integrated system must be tested, inspected, and found to comply with specific performance standards. In addition, Section 7 of the TT31 installation manual indicates that a post installation check should be carried out to verify correct Mode S address programming. A Mode S test set is required for this testing.
For proper certification, these sets must be conducted by a certified repair station with a Class III radio rating or limited rating appropriate to the test being performed.
In order to receive the Shop price for the TT31 transponder interested parties must submit a Repair Station license and Operation Specifications certificate to Southeast Aerospace.
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.
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.
Will the Trig TT31 transponder interface with the Garmin GNS430/530 series units for ADS-B functionality?
Configuration and programming of the TT31 transponder is simple. Hold down the FUNC button while switching on the transponder and the setup system will run. The setup includes the following configurations items: Mode S Address, VFR Squawk Code, VFR Flight ID, Aircraft Maximum Airspeed, Aircraft Category, Squat switch source, if installed, GPS position source, if installed, ADS-B parameters, Audio Output Volume, LCD Dimming Settings.
All programming is performed using the right hand knob and the ENT, BACK, FUNC buttons.
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.
TT31 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
How does the Trig TT31 compare to the Bendix/King KT-76C?
The Trig TT31 Mode S Transponder is a cost-effective replacement for the Bendix/King KT-76C, especially since it is a direct replacement for KT-76A, KT-78A and KT-76C transponders with no installation changes.
For quick reference, please review the outline comparison of the KT-76C vs. TT31:
FEATURE
KT-76C
TT31
ADS-B Capable
No
Yes, 1090ES
Altitude Monitor
No
Yes
Current Draw (14V)
1.6 Amps
.63 Amps
Flight ID Display
No
Yes
GPS Input
No
Yes
Mode S
No
Yes, Level 2
Power
200 watts
240 watts
Solid State
No, PA Tube
Yes
Timer
No
Yes
TSO
C74c
C112
Warranty
2 Years
2 Years
Weight
2.4 lbs.
2.8 lbs.
Should a new transponder certification be performed if simply replacing an existing transponder?
Yes, anytime a transponder is removed or replaced an altitude correlation between what the transponder is reporting and what is displayed on the altimeter needs to be performed. This is outlined in FAA CFR Part 91.413. This regulation indicates that following any installation or maintenance of a transponder where data correspondence error could be introduced, the integrated system has been tested, inspected, and found to comply with paragraph (c), appendix E. Furthermore, these references indicate that an integration test between the altitude reporting equipment and transponder system must be conducted.
For complete information, please refer to these FAA regulations or contact Southeast Aerospace Tech Support team at shop@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).
Why is the KT-79 not an ideal choice for a new transponder installation?
The KT-79 is a basic digital Mode C transponder. Due to its age, components for the transmitter assembly are no longer available from Honeywell. Therefore, due to inevitable reliability and warranty issues, the KT-79 is not an ideal choice for a transponder installation. SEA offers many transponders available in the same price range with more features to consider.
SEA suggests the Trig TT31. The TT31 is a Mode S level 2 datalink transponder with extended squitter, which also supports growing ADS-B technology, available in the same price range as the KT-79.
KT-79
Trig TT31
Does Southeast Aerospace offer "Shop" pricing for the TT31 Mode S Transponder?
Yes, SEA does offer a "shop" price for the TT31 to certified repair stations that meet the following criteria:
Per FAA Part 91.413 (ATC transponder tests and inspections), after any installation or maintenance on an ATC transponder, the integrated system must be tested, inspected, and found to comply with specific performance standards. In addition, Section 7 of the TT31 installation manual indicates that a post installation check should be carried out to verify correct Mode S address programming. A Mode S test set is required for this testing.
For proper certification, these sets must be conducted by a certified repair station with a Class III radio rating or limited rating appropriate to the test being performed.
In order to receive the Shop price for the TT31 transponder interested parties must submit a Repair Station license and Operation Specifications certificate to Southeast Aerospace.
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.
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.
Will the Trig TT31 transponder interface with the Garmin GNS430/530 series units for ADS-B functionality?
Configuration and programming of the TT31 transponder is simple. Hold down the FUNC button while switching on the transponder and the setup system will run. The setup includes the following configurations items: Mode S Address, VFR Squawk Code, VFR Flight ID, Aircraft Maximum Airspeed, Aircraft Category, Squat switch source, if installed, GPS position source, if installed, ADS-B parameters, Audio Output Volume, LCD Dimming Settings.
All programming is performed using the right hand knob and the ENT, BACK, FUNC buttons.
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.
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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