This INAV Fixed Wing setup guide is an overview of the features in configurator that you need to set. We have a “Getting Started with INAV” document. This covers things you need to know about INAV, upfront, before you dive in. If this is your first time reading this document, please go to it now. There are things you should know before working with your flight controller.

This document started from notes that Georgios Ntanas (a group member) made from watching Paweł Spychalski’s videos on INAV. Paweł is an INAV developer and a group member. Thank you also to Leslie Wr (yet another group member) for bringing this document to our attention. To clarify I wanted to modify the document to highlight the sections people seem to struggle with the most. The information about INAV changes from time to time. Please let me (Steve Schlesinger, INAV Fixed Wing Facebook Group admin) know of any changes or things that need addressing. Ultimately, our goal is to get you up and running with INAV as quickly as possible, with the least amount of problems.

Please note that this guide is going over the features of INAV Configurator. It should be used to get your plane ready to fly.

Once you are ready to fly, you should use our tuning guides to get your plane flying great.

We’ll go down each menu item on the left, in order. This guide is based on Paweł’s video. Subsequently there are links to the exact moment he discussed the specific tab. Thus you won’t need to do any searching. In his video he set up a flying wing. A flying wing is a good first plane to build with INAV. His video is based on INAV 2.0 which is now out of date. However, a lot of the information is the same.

Pre-requisites

Importance: Essential
Difficulty: Easy

When you plug your flight controller into the USB, lights will start flashing and hopefully, you’ll get the USB sound notification. We’re going to assume you’ve flashed the board and you can connect.

However, if you can’t do either, make sure that INAV is using the correct COM port. If it shows COM 1, it has likely not detected the correct port, so change this. If you only see COM 1, you probably have a driver issue, so go through the steps on the opening screen of INAV Configurator. Also, if you can’t flash or enter DFU mode, download and run the ImpulceRC Driver Fixer, which will resolve this problem. If you are still struggling, drop a message in the group and folks will walk you through it.

Setup Tab

Importance: Medium
Difficulty: Easy

In the main window of the Setup page, you will see a block which represents the flight controller. In INAV 3.0 onwards, this is now a flying wing. So as you move the flight controller the block on the setup should show your flight controller moving in the same direction. To make this easier to visualise, have the arrow of the flight controller, or nose of the aircraft pointing away from you. Now click the Reset Z axis button. As a result, the flight controller/model and block on screen will now be aligned.

The indicators on the right all need to be green before the plane will arm. If your plane refuses to arm, this screen is a valuable resource in helping to tell you what’s wrong. See our Basic troubleshooting guide for more information. Typing status in the CLI can also help figure out problems.

Calibration Tab

Importance: Essential
Difficulty: Easy

This page is where you teach your flight controller its level position all the different axis. Ideally, don’t have the board in the plane to perform this step. It’s recommended not to calibrate when its in the plane, thought it can still be done. Set the board on a table or other flat surface and record the first position. You’ll find that the first time you click the Calibrate Accelerometer button, it pops up a warning. So, click the button again to record the first position. Then move the flight controller on to the each axis and click the button each time, to record that level. It may be helpful to use a box for the side positions, and the underside of the table for the upside down position. Don’t forget to save and reboot.

A common problem for planes is that true level flight will have the tendency to push the nose down. Therefore, most planes can benefit from a nose up attitude of a few degrees. When you get to your first flight and notice that the plane tends to nose down in the self levelling modes (Angle and Horizon), this is normal. We can correct this with pitch offset on the flight controller during test flights.

Mixer Tab

Importance: High
Difficulty: Easy

This is the page where you tell INAV what control surfaces the plane has. As a result, the flight controller will do the mixing for you. Simply select Aeroplane for the platform. Then select your style of plane from the mixer preset drop down menu. Click save and reboot. Most of the heavy lifting has been done for you with this.

IMPORTANT: Do not do any mixing at all in your transmitter. Center your trim, 0 your expo. THIS IS HIGHLY IMPORTANT! This includes NO mixing if you have a delta, v-tail, or some other custom setups in your radio; you need to change the mix to a standard plane.

Outputs Tab

Importance: High
Difficulty: Easy

Motor and ESC settings

Make sure that Enable motor and servo output is enabled. Select the corresponding ESC protocol and ESC refresh rate for your ESC. You can also change the Servo refresh rate here. In most cases, it should be left at 50Hz. However, digital servos can run faster refresh rates, check with the manufacturer. An important setting in particular to make sure is enabled is Stop motors on low throttle. It’s the setting with the big, red box above it. This will stop propellers spinning when the throttle is low and save fingers.

We can also set the Motor IDLE power[%]. This is the percentage of throttle that the motor will engage. You can set this as low as possible before the motor starts to stutter.

Another option that is here, that most of the time we don’t need to worry about it the Number of motor poles. This is the number of magnets inside the motor. In most cases, the motors we fly with have 14 poles. But some motors, for example inrunners, have a different number of poles.

We can use the Motors section to test our motor is connected and working. With the propeller off and a battery connected, click the switch to Enable motor control. After that you can raise the motor slider to power your motor(s). If the motors spin up, you know they are working. You don’t need to disable all the safety features so that you can arm and use the throttle on your transmitter, this is enough.

Don’t forget to Save and reboot after making your changes.

Calibrating a non-DSHOT ESC

While we’re here, we can calibrate our ESC. This is not necessary for DSHOT. Disconnect your battery, Enable motor outputs, and slider the master throttle to 100%. Now plug in your battery. When the ESC stops playing a little tune, lower the master throttle to all the way down. The ESC will beep, then do the normal startup beeps. Your ESCs are now calibrated.

Servo settings

This video, is for the old Servos page. But a lot of the information still holds true for this section.

This section is where we can adjust the end and mid points of the servo if we need to. There is also the Rate (%) column, which changes the total throw of the servo, like traditional transmitter rates. The part we will use the most is the Reverse column. This is where we reverse servos if need be. For example, if we have a model with elevons or a V-tail; one of the servos will need to be reversed for it to function correctly. Make sure that everything is working correctly in the Receiver page before changing anything here. Don’t forget to Save and reboot after making your changes.

Presets Tab

Importance: High
Difficulty: Easy

Presets are what gives iNav a starting point for the PIDs and other tuning settings. You want to chose a preset of a plane that is similar physical to your plane. Don’t pay too much attention to control surfaces, but more the wingspan and physical size and shape. Chances are you won’t find an exact preset for your plane. But, find something as close as possible. After you select it, click the apply button. You can continue on to the manual process in step 9 if you want to do this manually (Not suggested).

Ports Tab

Importance: High
Difficulty: Medium

This page is where you tell INAV what type of peripherals you are using and where it is connected on your FC. The video does not spend much time here, because the settings will vary depending on your particular setup. If this is new to you, you’ll need to see Appendix 2 for instructions on setting up a receiver (Rx) with your flight controller.

As complex as this may sound, it’s as simple as finding where you physically connected your peripheral, such as a receiver, to your flight controller. In other words, which UART its plugged/soldered to. For a receiver, you would enable Serial RX on the INAV serial port that corresponds with the UART it’s connected to. Click save and reboot when you’re done setting up your devices.

Don’t let the word UART scare you. If you would like an explanation of UARTs, check out this video. The pins or pads you attach your device to, dictate which UART ports you are to using. This is also where you will learn if you need to buy a new radio system. If you’re going to fly with a flight controller, you should have a system that takes advantage of serial-based receivers. Before you buy anything, watch videos and ask questions. FrSky uses OpenTX which has its own learning curve. There are other options in the market. Pick people’s minds in the group. Take your time and research your options. From this point on we’ll assume you have the radio system installed and working.

Configuration Tab

Importance: High
Difficulty: Medium/Hard

At this point, it is assumed your flight controller is working and is installed in your plane. We also assume that all the devices that you want to use with the flight controller are connected and set in the ports page.

Receiver Tab

Importance: High
Difficulty: Easy

In the video, this is shown on the Configuration page. However, this has all now been moved to the Receiver tab.

I’m sure you guessed what we’re setting up on the receiver page right? The video transmitter of course. Only kidding. The first thing to setup on the Receiver page is the type of receiver you’re using. In most cases this will be Serial-based receiver, but some older transmission protocols have also been included. Next set the data protocol for your receiver. This will be specific to the system you are using, for example SBUS, TBS Crossfire, IBUS, etc.

It is then very important to make sure that your radio is sending the correct information to INAV. There should just be a standard plane mix in the transmitter. Nothing fancy, even if your model is a wing or v-tail. We use the bars on the left to make sure everything is working as it should. Make sure that the correct stick movement is controlling the bar for that control movement. You also want to make sure that sticks down or left shows 1000 in the bar, and up or right shows 2000. The centre positions should show 1500, though you don’t need to worry too much about the centre for the throttle. If this sounds a little confusing, this video will help.

Board alignment

Back on the Configuration page, the next thing we may need to change is in the board and sensor alignment section. This is the section where we can correct the pitch of the model to fly straight in Angle mode, hands off. As well as correct for the physical installation of the flight controller.

If the arrow on your flight controller is not pointing towards the front of the model, you will need to correct the board alignment. For example, the most common practice is to rotate the flight controller to make accessing the USB port easier. In this example you would tell INAV the board is rotated on the yaw axis. Depending on the flight controller, it could be 90, 180, or 270 degrees of rotation. Performance won’t suffer because of this, you can even mount it upside down.

One thing to note is that all the alignment adjustments are based on the direction of the arrow on the flight controller. So if your flight controller is rotated 90 or 270 degrees, and you want to correct the pitch for straight and level flight, hands off in Angle mode. You will need to change the roll axis, not the pitch. This video may help you figure out the alignment.

System configuration and sensors

In System configuration, we can change the Gyroscope LPF cutoff frequency and the Flight controller Loop Time. For the LPF cutoff, we want to use as high a number as possible, so start with 256Hz. However, if our model has a lot of vibrations, we may need to reduce this. If you have to go below 40Hz, you should look to fix the physical vibrations on your plane.

The Flight Controller Loop Time should be set as high as possible, without causing too high a CPU Load (see the bottom strip of Configurator). For the most cases, 1kHz is absolutely fine.

If you have connected a device, like a magnetometer. It should appear in the Sensors list. The Barometer and Accelerometer that are built on to your flight controller should also be here. If the have not appeared, set the drop down list option to AUTO, then save and reboot. If they still do not appear, there is an issue. For external sensors, check the wiring. For onboard sensors, check that there is not a conflicting device, for example an OLED screen with the same address as the Barometer.

Battery Voltage and Current Sensor

Most flight controllers that have a VBAT or VCC pad can detect the battery voltage. However, if you have an all-in-one board, like the Matek F405-WING, this is guaranteed, plus you have current sensing too. This will give useful information in the OSD, so you can monitor your flight.

Battery Voltage

In this section, we can set up how our batteries are monitored. The first thing is to make sure that Battery voltage monitoring is enabled. We can then choose how we see the voltage displayed, either as the raw reading from the sensor, or sag compensated. Sag compensated is an estimation of the pack voltage without load.

For Number of cells, leave that as 0, which is automatic. If you find that the number of cells is being incorrectly calculated, you may need to change the Maximum cell voltage for cell count detection setting. 4.3V is fine for most cases, but you may need to increase it if you use hi-volt packs.

The Minimum Cell Voltage, Maximum Cell Voltage, and Warning Cell Voltage are fine for most applications. However, for Hi-volt, you may want to increase the Maximum. Also for LiIon packs, you will want to reduce the Minimum and Warning voltages.

The most important thing, we’re getting to last. That is the Voltage Scale. The manufacturer of your flight controller should give you this scale. With companies like Matek, the scale is easy to find on their web site. Set the scale and save and reboot. Next get a multimeter and measure the pack voltage and compare it to the Battery Voltage shown below the scale. You may need to increase or decrease the scale slightly to get a perfect match. However, I’ve found the Matek scales to be very accurate. If you can’t find a scale for your flight controller, start with 1100 and adjust based on multimeter readings. Don’t forget to save and reboot once you’ve made your changes.

Current Sensor

If you have a current sensor, you can enabled Battery current monitoring. Like with the voltage sensor, your flight controller or PDB manufacturer should have a scale for the current sensor. Enter that and save and reboot. There are two ways to get a more accurate current sensor reading.

The first is not the best way, in fact I would recommend against it with a Matek FC as the base sensor scale will be just as close. However, it just involves flying and charging packs, so easy. There is an explanation and calculator for that on this site.

The second, and most accurate way to calibrate the current sensor, involves powering up your model and taking readings. So please consider all safety precautions before attempting this. This will actually give you a new scale and an offset for that scale. That method can be found here.

Make sure to save and reboot when you’re done.

GPS

There are a few things that we can set for our GPS module on the Configuration page. Firstly, if we have one we need to enabled it, so make sure the switch for GPS for navigation and telemetry is blue.

Next up we have the Protocol. Most GPS modules that we use now will be UBLOX or UBLOX7. If you have a UBLOX GPS, try UBLOX7. It won’t hurt it. To know if it’s ok, you can check in the GPS tab. Under UBLOX the update time will be around 5.0 Hz. With UBLOX7, this will now be around 10.0 Hz, but make sure that everything else on that page is working as expected.

The last thing in the GPS area is Ground Assistance Type. Unless you are constantly travelling to different countries with your models, there’s no reason not to set this. It will give more accurate altitude figures by selecting your location from the list. Once you’re ready, save and reboot.

Other Features

Under Other Features, there are a couple of things we should check are enabled, with a blue switch:

  • Stop motors on low throttle
  • Telemetry output (only if you have a receiver that can send back telemetry)
  • Enable motor and servo output
  • OSD
  • Permanently enable AIRMODE

Save and reboot.

Failsafe tab

The first thing that should be mentioned is do not touch the settings in the Valid Pulse Range Settings box. They should be left standard. However, over in the Settings box, there are a couple of things to look at. The first is Failsafe Kill Switch. We need to make sure that this is off. The next is Guard time, which is a delay before triggering the first stage of failsafe. By default it is set to 5, which is 1/2 a second. This is fine in most cases. Next we’ll look at the failsafe Procedure.

If your plane doesn’t have GPS, just set failsafe Procedure to Land. Make sure that Throttle used while landing is 1000. The lack of a GPS unit means your plane has no idea where it is, so Return To Home isn’t even an option. This is why GPS units are highly recommended. In a Land failsafe, the plane is going down where it lost signal.

Note: The word “land” implies that the plane will drop the landing gear, drop the flaps and setup for a perfect landing. Nope, it just glide in a spiral until it hits the ground. GPS are cheap enough that you should have one on every INAV plane you own.

If your plane has a GPS unit, select RTH (Return To Home). Click Save and Reboot.

There is a lot to RTH, and most of it is set up was using the CLI. But in from 2.6 it is on the Advanced Tuning page. When using the right setup, it works well and it’s amazing. There are a lot of ways to change return to home so that the model returns at a certain altitude, holds it’s the current altitude, or climbs back up to the highest altitude of the flight. We cover this in our Modes guide. You will need to test RTH before you can rely on it. It may not work perfectly on your maiden flight.

Testing Failsafe

Desktop Failsafe Test

At the top of the configurator screen, just left of center, there is a small info panel. The middle icon looks like a parachute and should be grey when your transmitter is switched on. Turn off the transmitter and the parachute should turn red. If this has happened, it’s indicating that Failsafe has activated! Switch the transmitter back on, and the parachute should go grey again. This means that everything has re-bound and you have control.

If this is not the case, failsafe has not been setup correctly on your receiver. Ideally you should use a receiver failsafe mode that sends to the flight controller that it is in a failsafe condition, not put controls in certain positions. For example, on FrSky this setting is NO PULSES or HOLD and Crossfire it is called Cut. You must get the parachute lighting up correctly before progressing further.

Flying Field Failsafe Ground Test

In this next step, we can not only verify that failsafe being detected, but that the procedure we have chosen is being activated too. Please remove your props! When your model is set up and powered on, arm it and apply about 1/4 throttle. Now run with the model and transmitter away from the place where you armed. You need to be at least 50 metres/165 feet away from the home point (where you armed). Now, switch off the transmitter.

If the failsafe procedure is set to land, the motor should stop.

If the failsafe procedure is set to RTH, which should be 99% of INAV builds. The aircraft should try to climb. So the throttle should raise and the control surfaces should move to pitch up, or turn, depending on your RTH settings.

In either case, switch your transmitter back on and clear any messages on your transmitter. Move the roll/pitch stick to see if you have regained control.

In-Flight Testing

The final, optional, stage of testing is to switch off your transmitter in flight. Please only do this once you have tuned your plane and it is flying stably in automated flight modes. See our tuning masterclass to get your plane flying great.

Do not do this if you have set the failsafe procedure to land.
Do not do this if you have not configured and fully tested your Return To Home procedures.

Before trying this, it would be a good idea to familiarise yourself with what is going to happen during this test. The last thing you want to do is panic.

  • So, what we are going to do is take off or launch your model and fly at least 50m away from the home point.
  • It would be a good idea to get plenty of altitude here, like 100m/330ft.
  • It would also be good to have some speed, so in the worst case scenario, something goes wrong, and the motor stops; we have plenty of momentum to glide until we can regain control.
  • Keep in your mind the procedure to re-arm, we shouldn’t need it. But remember disarm, lower the throttle, arm, raise the throttle.

Now we know what to expect, we can carry out this test. It should go without saying that you need to put your props back on for this. Launch, get in position, take a deep breath, and switch off the transmitter. If all is well, the model will fly back to the home position and start loitering above you. If the previous two tests were successful, there is no reason why this would not be the case. Switch the transmitter back on, bring it in to land, and have a well deserved sigh of relief/change your pants.

If it doesn’t, switch the transmitter back on and re-establish a connection with the model. If you don’t get control back straight away, look at the system messages on your OSD and do as asked to regain control. You will need to investigate why RTH failed to activate. Asking in the group can help with this.

PID Tuning

Importance: Low/Medium
Difficulty: Medium/High

This section is by far the place where you can make your plane your own. Most of the flying issues with INAV can be fixed here. But, you’ve got to know what you’re doing. We included the section where Paweł talks about PID/PIFF tuning in his video. If you’d like to follow along with him, do so at your own risk. If you’re new, you’re better off using a preset.

One of the reasons why we picked up a dot com for the group is so that we can easily share help and advice in one easy to find place. We do have other guides written by Marc Hoffman such at the INAV Tuning Masterclass that you’ll find to be really helpful.

Modes Tab

Importance: High
Difficulty: Low/Medium

Frankly, this is a subject that is too broad to cover in this document. We have a modes guide that covers this in more detail. The most important thing is to understand what each mode does before you assign a switch to it. It’s really in your best interest to start with the basics and then add more modes over time.

If you don’t have a working GPS, some modes won’t appear. This isn’t very well documented. For example, if you want to see NAV RTH and NAV Cruise modes, you’ll need to have your GPS setup. The key modes you’ll want to get started with are: Arm, Angle, Acro (no mode selected), Manual, and Nav RTH

NOTE: On this site we have OpenTX based transmitter models. We have a complete build with modes already set up. This is a great system for getting started quickly.

Now there are a few very good options for OpenTX radios that are reasonably priced. FrSky Taranis, Horus, and RadioMaster’s line of OpenTX transmitters along with some others. The OpenTX platform is fairly difficult to get started with. The group models that Darren Lines made for OpenTX makes it surprisingly simple. They’re nicely setup, logical, and a lot of us are using them. We put in a lot of time and effort to get this build right. They’re free and it may just push you into the OpenTX platform. Without a doubt, nearly all the most useful modes are setup.

If you want to use another radio platform, watch the video link and give it a go.

OSD Tab

Importance: Medium
Difficulty: Low/Medium

As you can tell, there are many things you can put on your OSD screen. But, how much do you really need? It’s easy to flip on everything, but the screens do get crowded. Thankfully you can now have a default plus 3 different OSD screens! You need to go back to the “Modes” tab to set up changing screens with switches or knobs.

It’s time for a little free advice. If this is your first OSD experience, just use the default OSD without using the alternative OSD screens. It’s basic and simple, but it will get you where you need to go. There are probably 100 different options for OSD screen functions.

Steve’s OSD setup

I will explain how I have mine setup. It’s with the three screens.

OSD #1. Trash Burrito Screen

The screen is basically filled with fonts. I have the name of the plane, the number of satellites, and a ton of PID info on this screen. It is undeniably full of information. But, I only use this screen for arming the plane. Once it’s armed, I don’t need most of these values. I record all my flights on my goggles and dump them onto a huge hard drive in folders based on the plane. As start to record I get the name of the plane, when I arm I get the date. I also have all my PIDs listed. This comes in handy as you play with PIDS. You can specifically go back and see how a plane has changed by seeing which values you’ve changed.

OSD #2. My primary flying mode

Over time I’ve added more stuff to this screen. I want to numbers to show me how much the plane is pitching and rolling. But all I really need to know is how high up I am, how far away I am, how much power I’m consuming, and how to get back.

OSD #3. The simple one

This is a more simplified screen with an artificial horizon and as little as possible on the screen. I prefer to fly without the artificial horizon.

In updating this document, Marc Hoffman has suggested that there is a setting where you can have the OSD go back to the default OSD when you go into Failsafe. This would be the fourth OSD screen. I am going to try it out. This would be a good time to flash the number of satellites, craft name, GPS coordinates direction to home and perhaps an artificial horizon. Keep it simple and basic and make it look different so that you know right away you’re in failsafe. The CLI command for this is:

set osd_failsafe_switch_layout = on
save

LED Tab

Importance: Low
Difficulty: Low/Medium

If you are using an LED strip, you first need to enable that function from the configuration page and Save and Reboot. Then go to the LED tab and set up your programmable LED strip according to your liking. Click Save and Reboot.

LED’s are something that we picked up from our drone brothers. Because if they’re flying line of sight they use them to know what their orientation is. Additionally, they are use for bling at races. If you do a lot of flying at dusk or dawn this may be useful, although more for showing off if flying FPV. The LEDs need to be the WS2812 addressable type. There are LED’s with beepers that are generally inexpensive and not too difficult to install. This is something you can check into as you get deeper into INAV. One idea from our moderator Jason is to set the LED to come on when the plane is armed.

There is actually a lot to LEDs. It’s a bit of a learning curve because they can be programmed. You may want to watch a YouTube video to learn more.

CLI Tab

Importance: Medium
Difficulty: Medium/High

In the link, Paweł gave some advice about changing the I term. Use it at your own discretion.

The CLI page is the command line interface for INAV. It is used to set some commands that are not in the main configurator interface. It’s also useful for getting information. To illustrate I’ll go over a few commands that you may find useful. Don’t worry, if you set a value incorrectly, because you will get a warning and the value won’t save.

version

Displays the version and target of INAV on the flight controller. If you have an old version of INAV on a flight controller, INAV configurator may dump you into CLI. Type “Version” and hit return. This will at very least let you know which target to flash. Also the version will help you find the steps needed to update to the latest release.

status

Shows the current status of the flight controller; including if you have any errors preventing you from arming. There is a page on GitHub to clarify the errors, and enable you to fix them.

dump

This is the full list of settings for INAV. Therefore you can use this to back up and restore all the settings on your flight controller.

diff

This is similar to dump, but it only list the settings you’ve changed. You can also use diff all which gets the changes you’ve made and profiles.

defaults

Whenever I flash a flight controller the first thing I do is go into CLI and type this. It’s a hard reset back to the default settings. Sometimes there is residual garbage on a flight controller from a previous flash. This clears that out.

The full list of CLI Commands can be found here.

You should open up the dump file in a text editor like Notepad and look at it. At first it’s all overwhelming. After a while, you’ll start to notice that some of the values you changed in the configuration tabs are listed in this file. For example

set failsafe_procedure = RTH

We’ve mentioned in the Failsafe tab that you can turn on RTH if you have a GPS. Furthermore if you just copy this text and paste it in to the CLI and type save, it will set this for you. What’s more, you can come up with a list of commands to use for every new build. As a result, you can save time with a copy and paste of all your standard settings.

GPS Tab

Importance: Medium
Difficulty: Medium

GPS setup can be tricky the first time around. But, the newer GPS modules and latest firmware releases have made it easier. It’s actually quite simple in theory.

There are four wires on a GPS. Power, ground, TX, and RX. Some modules also have an SDA and SLC wire. But they’re for the compass, and we don’t need to worry about those. The GPS RX wire goes to a TX port on your flight controller. Likewise, the TX from your GPS goes to the matching RX port on your flight controller. The little clue that they will give you is that the board will say something like TX3 and RX3. The 3 means you are using UART 3. In the Ports tab you simply enable the GPS peripheral for the GPS on UART 3; then click Save and reboot.

Here are the notes from Paweł’s video on GPS: M8N series GPS are highly recommended. He suggests the BN-880 or the BN-220 (My favorite GPS) and the Matek modules.

After the physical wiring up of the GPS, you still need to set it up in the configurator. Earlier we covered this in the Configuration section. But, here’s a quick recap.

  • In the ports page, find the UART that you have connected the GPS to. In the sensors column, select GPS from the drop down list. The standard baud rate of 115200 is usually fine. Save and Reboot.
  • In the Configuration page, go to the GPS section.
    • Enable GPS for navigation and telemetry.
    • Check the spec of your GPS module, and select the correct protocol. In most cases this will be UBLOX7 or UBLOX.
    • Enable Galileo satellites. Worst case, this does nothing. Best case, you have access to more satellites.
    • Select your region for the Ground Assistance Type.
  • Save and Reboot.

To see if GPS is working properly. Check for the blue icon on the top of the page. Then go to the GPS tab and check to see that the Total messages count is rising. If both of these are ok, the GPS is working. You may not be getting satellites because of your location.

Advanced Tuning Tab

Importance: Medium
Difficulty: Medium/High

Do not change anything in Position Estimator
Do not change anything in Multirotor Navigation Settings

Fixed Wing Navigation Settings

In the Fixed Wing Navigation Settings are some parameters that we will want to take a look at.

Throttle

The Cruise, Min., and Max. throttle settings will depend on your aircraft. The Min. and Max. throttle levels are the limits that the flight controller can go up or down to. For most, the default values are fine. The cruise throttle however, will need to be set with testing. You should put the throttle percentage on the OSD and fly in Angle mode. It needs to be set so that you can fly and bank stably, but slowly. You also want to have a ground speed higher than your average wind conditions. Take your throttle percentage × 10, then + 1000. For example, if you were cruising at 32% throttle, the value to put in the Cruise throttle field would be 1320.

The Pitch to throttle ratio is how INAV applies the throttle when in automated modes. Lower it if you see the craft is applying too much throttle when climbing. Likewise, increase if it doesn’t apply enough throttle while climbing, causing a stall. Consider tailwinds and headwinds for this setting. Usually, leaving this as-is will be ok for most planes that aren’t severely under-powered.

Angles

Max. bank angle [degrees] is used by all autonomous flight modes when turning. By default it is set to 20. Due to that setting, the model will make very wide turns. So you should increase it to 30-45, depending on your model.

The Max. Climb angle [degrees] can be changed, depending on the model. By default it is 20 degrees. But smaller wings or models with a good power to weight ratio can have a higher value. Be sure your craft can climb at the angle you have set, at the Max. throttle you have set in all conditions.

The Max. Dive angle [degrees] should be left at the default value of 15.

Loiter radius is preset to 5000 cm. This is 50 metres, meaning the total diameter of the circles will be 100 m. You can change this if you want a tighter radius but remember your wing might or might not be able to make a tight radius. Change the bank angle to be able to achieve a tighter radius. Large models may need a larger radius.

RTH and Landing Settings

The RTH altitude mode sets how the model will come back to you. You need to set this based on your environment. For a generally good setting, At least is a good choice. The modes are:

  • Current: The model will fly back at the current altitude.
  • Extra: The model will fly back at the current altitude, plus the height entered int the RTH altitude [cm] box.
  • Fixed: The model will always fly back at the altitude entered in the RTH altitude [cm] box.
  • Max: The model will return back at the highest altitude recorded so far in the flight.
  • At least: The model will return back at it’s current altitude; or the altitude set in RTH altitude [cm] if it is higher than the current altitude.
  • At least, linear descent: This will use the same technique as At least. Only it will, if it is higher than the RTH altitude [cm], it will slowly descend to reach RTH altitude [cm] when it arrives at home.

The RTH Altitude [cm] can be set as you like. But, make sure to take your environment into consideration. The default is 1000cm (10m), which is pretty low. Certainly low enough to end up stuck in trees. You could err on the side of caution and set it to 12000cm (120m). That will clear most things.

There is one setting that was missing in configurator is the RTH home altitude [cm]. This is now present from iNav 2.6. This setting allows you to set the altitude that the model will loiter down to when it reaches home. Say for example, you’re flying in the mountains, of course following the laws of your country. But, because of this you use the Max RTH mode, and you are quite high. This setting will mean the once the model reaches home, it will safely loiter down to the set home altitude. The example below would set the home altitude to 50m. Again, this is set in centimetres.

Climb before RTH is another flying environment question. If you’re flying in tight spaces, you will want this turned off. But if you’re in open spaces, you can have it on. Either way, you may have a situation where this setting may get you in trouble. My personal take is to have it switched off. It does mean that the model will be flying away from you still, until the RTH altitude is reached. But, I can’t imagine me flying at something that the model may crash into. But, there could be things to the side. This one is a personal call; you know where you fly better than we do.

These settings however, are simple: Climb regardless of position sensor should be disabled. Tail first should also be disabled.

Land after RTH depends on what you want and your environment.

  • Always: will descend slowly in circles with intent to land, every time you go into RTH. Make sure where you are flying there is enough space to do so. The plane will land (crash gently) into the ground.
  • Only on failsafe: will do the above, but only when there is a failsafe state. For example, if you fly out of transmitter range or your transmitter runs out of battery or you have a radio problem. In this mode the plane will not land if you enabled RTH on a switch.
  • Never: will never try to land the craft after it comes home. It will fly in circles above until the battery dies.

Only on failsafe is recommended and has saved many planes when people had radio problems. If you decide to use Only on failsafe, Leave Vertical landing speed at 200, change Min. vertical landing speed at altitude to 1500cm or 1000cm (15m or 10m). This is the height at which the plane will cut the motor and basically try to land softly. Leave all other numbers below as is.

Navigation Modes

Importance: Medium
Difficulty: Medium/High

We return to the modes page to set up the navigation modes. You will not see these modes if you don’t have a GPS unit enabled. The most useful automated flight modes are generally NAV CRUISE, NAV POSHOLD, and NAV RTH.

NAV CRUISE keeps the model flying in the same direction. It is even more useful to add NAV ALTHOLD on the same switch position to enable 3D CRUISE. This will keep the plane flying until you decide to change course.

NAV POSHOLD is what people generally refer to as loiter. This keeps the aircraft circling around the spot where it was switched on.

NAV RTH is used to bring the model back home on demand. However, some people incorrectly use the FAILSAFE mode for this. That is an improper use of that navigation mode. The FAILSAFE mode should only be used to activate failsafe, specifically with transmitters/receivers that can only set channel positions in a failsafe situation.

Another mode that you could add is NAV LAUNCH. As mentioned before, this mode assists with launching the model. NAV LAUNCH can also be permanently enabled on the Configuration page. Check out our How to setup NAV LAUNCH correctly guide for more details.

After you are done don’t forget to click save and reboot.

For more info on all the modes, go to the iNav website at https://github.com/iNavFlight/inav/wiki/Flight-modes