Introduction

The INAV Fixed Wing Group have produced a model for most transmitters running OpenTX. The aim of the standard INAV FWG OpenTX model is to get new people up in the air quicker. Also, having a base layout, which will make helping easier too. OpenTX is a very powerful operating system, so it’s well worth learning and checking out what else it can do.

Download the Standard Model Here

Click the link below to download the latest version of the INAV Fixed Wing Group OpenTX model pack

Download the OpenTX Model

So, if you’ve been using INAV for some time, and are an advanced pilot. You may wish to check out our Pro OpenTX Model. That may be more suited to you.

Version 2

In this new version of the Standard OpenTX model, a few changes have been made. Particularly, if you have been using the original Standard model, you will notice that the switch positions have changed. If you prefer not to change switch positions, version 1 is still available here. However new switch layout will make switching to the Pro model in the future easier. We have also changed the mechanism behind the arm switch, to make it simpler to reverse. We have also enhanced the multi-function momentary switch.

Transmitters and Versions

These models were built using OpenTX Companion 2.3.10. However, due to the functionality in the models; it should work fine in older and newer versions too.

Supported Transmitters

  • FrSky Horus X10, X10S, X10 Express, and X10S Express
  • FrSky Horus X12S
  • Jumper T12, T12 Pro, T16, T16 Plus, T16 Pro T16 Pro V2, and T18
  • RadioMaster TX16S
  • FrSky Taranis Q-X7, Q-X7S, Q-X7 ACCESS, and Q-X7S ACCESS
  • FrSky Taranis X9D, X9D Plus, X9D Plus SE, X9D Plus 2019, and X9D Plus SE 2019

You will find an appropriately named model in the zip file for your transmitter.

Features

We have worked on the switch layout, specifically to optimise it. It also now closely matches the switch layout of the Pro model. This layout, as well as some additional features, will help get people in the air quicker.

We have tried to cater for all pilots. So, while there may be flight modes that you personally wouldn’t use, others may find them invaluable. We all fly differently, some are in it for speed, others distance, others like to just get up in the sky, relax, and enjoy the view. So with these models, we hope to be able to cover all bases and include as many people as possible.

Switch Layout

The layout above is using a Horus X10S Express. However, the switch names will match to your transmitter. With the exception of the Jumper T12. Specifically on that transmitter, switch G is the arming switch.

Arming

The arming switch now has its own channel. This makes reversal simple (documented below) and also allows you to change flight modes on the bench.

Flight and Navigation Modes

You find the flight and navigation modes on switches SA, SB, and SD. There is a mode order, so that the safest modes will take priority. For example, Return to Home will take priority over every other flight mode. The order is:

  1. Return to Home
  2. Manual
  3. 3D Cruise
  4. Position Hold
  5. Angle – Horizon – Acro

All flight modes have voice confirmation. If not using the flight modes on switches SB and SD, they need to be in the middle position.

Multi-function Momentary switch

You can use the momentary switch SH as a shortcut to perform functions. Firstly, hold the switch in and you will hear options. Then, release the switch on the option you want to use. The beep at the end signifies that no option will be performed.

  • Reset the flight timer
  • Enter the INAV OSD menu*
  • Save the current configuration *

* Requires you to be disarmed

OSDs

The OSD selector is no on the S1 pot. You now have access to 5 different OSD options: default, alt 1, alt 2, alt 3, and off. INAV will select the default OSD automatically during failsafe.

Tuning

You can select servo autotrim and autotune via switch SC. A voice confirmation will let you which mode has been selected. There is reminder beep while you are in servo autotrim or auto tune. Also, there is a mechanism that won’t let you arm in either servo autotrim or autotune modes. There is also a reminder to save the settings after using autotune.

Arming Warning System

A feature we have added is a smart arming system. It will not let you arm the model if the throttle is not low or you are in a tuning mode. The system will also give you voice feedback on any actions that need to be taken. It will also tell you that the system is armed or disarmed.

Flight Timer

We have incorporated a flight timer on the model. It will start the timer once the you arm and raise the throttle. It will continue until you disarm. To reset the timer, hold SH until the first beep, then let go.

Installing on the Transmitter

If you would prefer to see the installation video, it can be found here.

Getting Everything Ready

Before we start, let’s make sure that we have everything we need to get you up and running. If you have installed this OpenTX model before. Please check the change log at the bottom of this document.

OpenTX Companion

The first thing you will need to download and install is OpenTX Companion. This is the software which lets you backup, update, and modify your Transmitter. You may already have this installed because its very useful. But if not, head over to https://www.open-tx.org/downloads.html where they have the latest version of Companion.

OpenTX Companion download page

At the top of the page, OpenTX shows the latest stable releases or branches. When we took this screen grab, OpenTX 2.2.3 (2019-01-06) was the latest release; as illustrated with the highlight. Click on the latest branch. The next page has release notes and also any warnings for the release. They are well worth reading. However, the part we are looking for is at the very bottom of the page. There are download links for the SD Card contents and what we’re looking for this time, OpenTX Companion. Download and install the correct version for your computer.

Please follow OpenTX’s guide to install and configure OpenTX Companion. The most important part is to select the correct transmitter and settings you need for the firmware downloads.

INAV Configurator

You will need to download and install the latest version of the INAV Configurator. You can find this at https://github.com/iNavFlight/inav-configurator/releases. The latest version will conveniently be at the top of the page.

INAV Configurator download page

Click on the current release, for example INAV Configurator 2.1.4 here. Then scroll down to find the installation files. Download and install the correct version for your computer.

INAV Fixed Wing Group OpenTX Model

You will need to download the model files from our web site.

OpenTX Options – Global Variables

For this setup to work, an option in OpenTX needs to be present. This is easy thing to check for. Its also easy to fix with a firmware update, if it’s not active. This feature should already be active, but we can check on the Transmitter it’s self before we go any further.

GLOBAL VARIABLES ON THE Q-X7(S)

On your Taranis press the menu button to go to the model select screen. From here press the page button until you reach the Flight Modes page. Press the enter button to edit the flight default mode FM0, then scroll down, where you should see a list of Global Variables.

FrSky Taranis Q-X7 showing global variables

If these variables are present, then you should all set and you can continue with the installation. If not, we need to enable the Global Variables by downloading firmware and installing it on the transmitter. There is an appendix at the end of the document showing this process. So, click here to jump to it.

Global Variables on the Taranis X9D (Plus/SE), Horus X10(S), & Horus X12S

On your transmitter press the menu button to go to the model select screen. From here basically press the page key to cycle through the menu pages. We are looking for a page with the name Global Variables, or GVARS; which should be between the Curves and Logical Switches pages.

FrSky Taranis X9D showing global variables

If this screen is present, then you’re all set and you can continue with the installation. If not, we need to enable the Global Variables by downloading firmware and installing it on the transmitter. There is an appendix at the end of the document showing this process. So, click here to jump to it.

Installing the OpenTX Model on Your Transmitter

Connecting to the Transmitter

To install the files on to your transmitter, you will need the appropriate USB cable to link the transmitter to the computer. Firstly, hold the roll and yaw trims towards the power button and switch the transmitter on. The screen should show the OTX Bootloader. You do not need to select any of the options on the screen. So, plug in the USB cable to the transmitter and the computer.

Installing the Sound Pack

Example of the files on an OpenTX SD Card

Open your system’s file manager, for example Windows Explorer or macOS Finder. You will see two external devices for the Transmitter. One device will have the name of the transmitter, for example Taranis. The other may have the name USB Drive, and will look just like an external drive.

We will be working on the “USB Drive” external disk. If you open it you will see the folders on the transmitter’s SD card. For example, it should look similar to the image shown on the right. Then, enter the SOUNDS folder, you will see folders for the installed languages on your transmitter.

Next, go to the place where you extracted the INAV Fixed Wing Group – OpenTX Standard Model Pack. Find the IFWG OpenTX Sound Pack – Vx.xx zip file. Then extract this file and go in to the IFWG OpenTX Sound Pack – Vx.xx folder. Inside there are folders for different languages packs. In the beginning there will only English (en), but we hope to add more as time goes on. Select the folder of the language that you would like to use and drag that folder into the SOUNDS folder on the SD card. This will then copy the new sounds file to your transmitter. This will not overwrite any existing sound files you may have; for example amber will be safe.

Installing the Model

Backup Radio to File

Open OpenTX Companion. Firstly, make a backup of your current models and settings. To do this click the Backup Radio button on the left side menu, then save the file on your computer.

Next we will access the models that are already on your transmitter. To do this click the Read Models and Settings From Radio button, also on the left side menu. This will open a window containing all your transmitter’s models. You can easily edit models here by double clicking on the model name. The page sequence is basically the same as if you were editing directly on the transmitter.

Read Models and Settings From Radio

Now use the File menu and click the Open… option. Find the models that you downloaded from the INAV Fixed Wing Group. Then load the model that you wish to use into OpenTX Companion.

Now we have a choice where we can create a new model on the transmitter, or overwrite an existing model. To create a new mode, click and hold on the model, drag it to an empty space in your model list, then release. This will copy the model to your transmitters’ list.

Copying a model in OpenTX Companion

To replace an existing model, we add an extra step which should save to from having to rebind to your receiver. Firstly, double click on the model that you would like to replace; this will open the Editing Mode window. There is a section on this page showing the details of your radio setup.

OpenTX Companion - Radio selection

What we need to do is take a note of the settings used by the radio, in particular the receiver number. Next click and hold on the model, drag it over the model you want to replace, then let go. OpenTX Companion will ask you if you want to replace an existing model. Click yes. Double click on the model again, only this time you will be setting the radio settings back, based on the notes you previously took. This should mean that you will not need to rebind the model to your transmitter.

After either of these methods, you can now double click on the model and rename it to something meaningful to you. Finally, upload the models back on to your transmitter. Click the Write Models and Settings To Radio button, this will pop up a dialogue box, where you would then click Write to TX.

Once the writing has completed, you can unplug the USB cable and switch off your transmitter. The next time you power it on, the model will be ready for you to use.

You will need to edit the model to set up your receiver settings. By default, the Standard version is configured to use a D16 type receiver (which includes X4R, R-XSR, S6R, etc). It is set to 8 channels, to keep the transmissions in a single frame. The Pan and Tilt version is also set to D16 type receivers; but has been set to use 12 channels, which is the maximum for the L9R. The failsafe has already been set to No Pulses, which is the recommended setting for INAV. You will need to bind with your model’s receiver. 

If using the R9 system or Crossfire, you will need to disable the internal module and setup your external module. Don’t forget to set the R9 failsafe to Hold or No Pulses or the Crossfire failsafe to Cut.

Reversing the arm switch

To reverse the arm switch, on the transmitter, enter the model menu. Page through until you reach INPUTS. Find input 5, Arm. Then long press the enter button and choose Edit. Find the Weight and reverse it. For example 100 would become -100. Exit out of the edit screen back to inputs. Then long press the page button to go backwards through the menu, until you reach the setup page. Scroll down until you find the switch warnings. Reverse the position of the switch warning for switch SF. Exit, and you’re done.

The Schlesinger Mod – Using a pot for Servo Autotrim and Auto-tune

The CEO of INAV Fixed Wing Group Inc, Steve Schlesinger, was pretty instrumental in the creation of the group’s first OpenTX model; Standard Model v1. One of the features that he really liked was having Servo Autotrim and Auto-tune on a pot instead of a switch. With version 2, the switches were aligned as much as possible with the pro model. This is for an easier upgrade path as pilots become more accustomed to iNav; and confident in their tuning abilities. But, we decided to add an option to move the tuning back to the pot. Maybe this will help people move from version 1 of the Standard OpenTX model, to this version. So, here’s how to make the change.

If using Companion, just go to the Inputs tab. If you’re on your transmitter, press the Menu button to enter the model menu. Then Page through to the INPUTS page. In the list, you will find Input 7 (I7), called Tun. This is the tuning input.

IFWG Standard OpenTX model v2 - Schlesinger mod - Switch SC

In Companion, double click on the input I7. Or, on your transmitter, jog down until you’re on I7. Then long press the Enter button (scroll wheel) and a menu will appear. Select Edit from this menu.

IFWG Standard OpenTX model v2 - Schlesinger mod - Pot S2

Find the Source. In Companion, click the drop down arrow and find S2. Select S2, then click OK. On the transmitter, click the Enter button on the Source, then turn the S2 pot. Click the Enter button again to set the new input source. Then click the Return button to exit all menus.

The S2 pot will now control Servo Autotrim and Auto-tune. If you wish to change it back at any point. Just repeat the above process, but select SC as the input source.

Setting up INAV

The final stage is to set up the modes in INAV. Connect your model via USB and open INAV Configurator. Click the Connect button and go to the bottom option in the menu on the left, CLI. You simply need to copy and paste the code below in to the CLI and press enter. INAV Configurator will save and reboot and you should be good to go. Please not that this is only going to set up the flight modes and enabled the default OSD on Failsafe, you should set everything else up before doing this step.

CLI commands

set osd_failsafe_switch_layout = ON
aux 0 0 0 900 1500
aux 1 1 1 1275 1375
aux 2 2 1 1450 1550
aux 3 3 1 1100 1200
aux 4 11 1 950 1050
aux 5 10 1 1950 2075
aux 6 45 1 1100 1200
aux 7 12 1 1800 1900
aux 8 37 2 900 1300
aux 9 21 2 1700 2100
aux 10 19 3 1800 2100
aux 11 42 3 1200 1400
aux 12 43 3 1400 1600
aux 13 44 3 1600 1800
aux 14 0 0 900 900
aux 15 0 0 900 900
aux 16 0 0 900 900
aux 17 0 0 900 900
aux 18 0 0 900 900
aux 19 0 0 900 900
save

Flight Modes Layout

Once rebooted, your flight modes should look like the graphic below. Unused modes have been graphically removed; but the order is the same.

The setup of the flight modes, and model installation is now complete. You will still need to set up the rest of INAV correctly before flying your model.

Autolaunch

As the model comes, autolaunch is not set up. This is because people prefer to use it in different ways. Some like a switch, others prefer it permanently enabled, while others don’t use it at all.

Unfortunately, the FrSky Taranis Q-X7 and Jumper T12 are at the limits of the available switches. So if you would like to use autolaunch, we recommend permanently enabling it. It can be disabled by by moving the pitch or roll after arming.

If you would like to add a switch for autolaunch, just follow these instructions.

Adding the switch on the transmitter

In this example, we will set up switch SG for autolaunch. First enter the model menu, then press the page button until you get to the mixer screen. Scroll down to CH9 and press enter. Give the mix the name Launch. Then scroll down to Source. Click enter and move the SG switch, then confirm with enter. You can then return out to the home screen.

Adding the switch in iNav

Next open iNav configurator, connect to the flight controller, and go to the modes page. Scroll down until you find NAV LAUNCH. Click the Add Range button and select CH9 from the drop down list. Move the switch in to the position where you would like launch to be active. Then move the range slider so that it is above the blue switch marker. Click save.

Autolaunch is now set up. You will need to configure the launch parameters for your model before you try to use it. Check out our guide for this.

Updating the Firmware to Enable Global Variables

Switch off your transmitter, then hold the yaw and roll trims toward the power button, then switch on the power. The OTX Bootloader menu should now be on the screen. Now take a USB cable and plug the transmitter in to your computer.

Launch OpenTX Companion. The first thing we should do is take a backup of your transmitter, just in case anything goes wrong. Click on the Backup Radio to File button, and save the transmitters data somewhere safe on your computer.

Once that is complete, click on the Read Models and Settings From Radio button in the left side menu. A list of the models on your transmitter will appear, but it will also copy the settings over.

OpenTX Companion settings

Now click on the Settings gear button in the top menu. A window which allows you to choose which optional features are on your transmitter will appear. The feature we are looking for is nogvars. We must make sure that this box is unchecked. Below is an image showing how the highlighted nogvars option should look. Please note that my Radio Type is a FrSky Taranis X9D+, you should have your correct radio type here.

OpenTX Companion - Make sure that nogvars is not enabled

Next, we need to download the OpenTX firmware.

OpenTX Companion - Download firmware

Click on the Download button, then choose Download Firmware. Save the file on your computer; perhaps in an OpenTX firmware folder so that you can find it later.

Once the download is complete; you will be get a question asking if you would like to install the firmware now. Choose yes, and Companion will show another confirmation box, where you can also change your start screen. Click Write to TX and the update will start.

OpenTX Companion - Write the firmware now?
OpenTX Companion - Flash firmware

Once the update has completed, unplug the USB cable, and switch of the transmitter. When you switch the
transmitter back on, you should now be able to find the Global Variables page in the menu. To jump back to
the main document, click here.

Customising this model

If you are looking to customise this model, this page may help you.

Change log

V2.01

3rd January 2020

Bug fix – Enabling servo autotrim or auto-tune forced the pitch to 100%. This bug effected all transmitters except for the X9D.

To implement this fix manually, go to the Special Functions and find SF37. The switch needs to be changed from L34 to L39.

Addition – A text file called INAV Fixed Wing Group – Standard v2 logic.txt has been added to the zip file. This details what the logical switches do, just in case you are curious and what to see what’s happening under the hood.

v2.00

20th December 2020

This is a new major release of the OpenTX model. The following has changed:

  • New switch layout.
  • Converted to unified sound pack. There are also additional sounds that you can use, for example with camera switching, Pan & Tilt, and more. See the text file in the sound pack for details.
  • Simplified arm switch reversal.
  • Added save reminder after using autotune.
  • Enhanced the multi-function momentary switch.
  • Added separate model files for the Jumper T12, T16, and T18, and the RadioMaster TX16S.

If you are upgrading from the old standard model, and no longer wish to use it. You can safely remove the sound files that begin with i_. To do this, follow the manual to copy the sound pack over, up until the point where you can access the “USB Drive” and find the SOUNDS folder. Enter that SOUNDS folder, then the EN folder inside it. I there you will find the 15 files beginning with i_, which you can delete. From this version on, all of our OpenTX models will use the same sound packs.

v1.02

29th September 2019

  • Modified package to resolve compatibility issues.
  • There are now separate model files for the X9D, Q-X7, and Horus.
  • Renamed pack from Taranis to OpenTx.

If you have installed this pack before; please delete all 15 sounds beginning with i_ from your transmitter before continuing. To do this, follow the manual to copy the sound pack over, up until the point where you can access the “USB Drive” and find the SOUNDS folder. Enter that SOUNDS folder, then the EN folder inside it. I there you will find the 15 files beginning with i_, which you can delete.

v1.01

21st April 2019

  • Minor update to the manual

v1.00

18th April 2019

  • Initial release