Software and Service Bulletins for pilots
Improvements and new features are available for your Trig product through software updates. These can be carried out by an Approved Trig Dealer, or suitably qualified installer. If you would like advice about the suitability, or need to update your Trig unit, please contact your local Approved Trig Dealer. They will be able to help you and organise the upgrade of your avionics.
The current version of software installed in your Trig product will be shown on the display at initial power up. Software versions run numerically, the higher the number the more recent the release – so the latest software will always include all the features of earlier versions.
The archive folders within the sidebar contains older versions of software. Once you have viewed an archive page, use the Back Button on your browser to return to this page.
Listed below are the current Trig product Software and Hardware versions.
Please note that Trig software versions use the numbering convention <MAJOR>.<MINOR>. The ‘.’ is not a decimal point. For example, version 1.12 is a later version than version 1.9
TT23/23G Transponders
15/07/2026 version 1.5
Under certain interrogation patterns, the TT23/TT23G may occasionally restart and then resume operation. This appears as the unit briefly entering standby mode before returning to normal operation. Software version 1.5 resolves this issue.
TT21 AND TT22 Transponder
17/04/2018 version 2.15
This software improves compatibility the popular IFR6000 transponder test sets.
TC20 Transponder control head
23/06/2025 version 1.16
This software introduces functionality needed to use the internal GPS in the TT23G transponder.
This software also removes the need to set some configuration items when connecting to a TN72.
This software corrects an error in software version 2.15 which may incorrectly configure an installation using the “TN72 SIL = 3” protocol. This version also renames the “Trig ADSB” protocol to “Avi/Trig” in the GPS selection setup menu to help avoid confusion with other protocol names that were similar.
TN70 GPS
10/05/2023 version C1.10-1
A limited number of TN70 GPS Position Source units have been identified by Trig as having been affected by a manufacturing error. This service bulletin allows for specific corrective action, allowing the reconfiguration of the IO communication protocol and the hardware modification status marking of the unit.
TY91 AND TY92 VHF RADIOS
19/10/2025 version 1.16
Software version 1.16 improves the squelch behaviour of the TY91/TY92 family of radios to reduce susceptibility to ambient noise and improves resilience to interference from aircraft equipment and engine RF noise.
TC90 VHF RADIO CONTROL HEAD
14/08/2024 version 1.9
This software fixes a bug that would sometimes cause frequency loading from a 3rd party GPS to fail when connected to dual control systems (systems with two TC90 controllers). This software also fixes an issue where the control head presented a spurious “no radio” warning when the radio continued to work as normal.
TX56 AND TX57 NAV/COM
Software
27/03/2026 Com version 1.3
Com software version 1.3 improves compatibility with 3rd party USB flash drives used for creating or editing
the frequency database.
Hardware
14/04/2024 SUP/TX56/004
Some TX56 family units were built with the volume and frequency knob retaining grub screws insufficiently torqued. Over time the loose grub screws could cause the knobs to feel less secure and could cause the painted line on the volume knob to become misaligned. This service bulletin describes the process of tightening the grub screws to the correct torque.
15/02/2023 SUP/TX56/002
A very limited number of TX56/56A units were shipped with a potentially defective locking cam screw. These units were shipped between 31st October 2022 and 28th November 2022. This hardware service bulletin defines the range of serial numbers affected, indicates the process to identify a defective locking cam screw and provides guidance on the rectification process.
TY96 AND TY97 VHF RADIO
Software
27/03/2026 version 1.11
Software version 1.11 improves compatibility with 3rd party USB flash drives used for creating or editing
the frequency database.
Hardware
14/04/2024 SUP/TY96/014
Some TY96 family units were built with the volume and frequency knob retaining grub screws insufficiently torqued. Over time the loose grub screws could cause the knobs to feel less secure and could cause the painted line on the volume knob to become misaligned. This service bulletin describes the process of tightening the grub screws to the correct torque.
15/02/2023 SUP/TY96/013
A very limited number of TY96A units were shipped with a potentially defective locking cam screw. These units were shipped between 31st October 2022 and 28th November 2022. This hardware service bulletin defines the range of serial numbers affected, indicates the process to identify a defective locking cam screw and provides guidance on the rectification process.
TT31 Transponder
Software
24/09/2018 version 3.18
TT31 software version 3.18 improves performance of Mode S replies to certain interrogations, correcting software versions 3.14, 3.15, 3.16 and 3.17.
Hardware
01/10/2018 SUP/TT31/027
This Hardware Service Bulletin applies to TT31 transponders approved under ETSO authorisation EASA.21O.643 Rev B and EASA.21O.906 Rev A, part number 00220-00-(XX) and part number 00225-00-(XX) which are:
- Serial number from 05767 to 09715;
- Modification Level 6 or below;
- Installed in an orientation which is NOT a conventional aft-facing avionics stack mounting.