The following is information pertaining to your flight controller. Please refer to this if you have issues with it’s setup. So if you have problems not allowing you to get the plane ready for maiden, or if an issue creeps up after many successful flights. If this doesn’t fix your problem, please see the Further support section at the end.

The flight controller won’t arm

Check the Setup page for pre-arming errors. INAV is wonderful because the red flags clearly tell you where the source of your problems are.

Go into the CLI page and type status hit RETURN. In the last line it should ONLY show CLI. If there is any other errors this is also where to start investigating.

The flight controller arms but motor won’t spin

Check the battery. Is it fully charged?

Do the servos react to stick inputs? 

INAV status display

Check ARM status at the top of the Configutator when connected: Triangle sign needs to be yellow, chute symbol grey and chain symbol blue. If you see these three things, then it is armed. Still no motor reaction? go to next step.

In the Outputs page, check the ESC Protocol on the left side. Set it to STANDARD and Click Save and Reboot. This is, because a lot of linear (plane) ESCs don’t support advanced Protocols like Multishot or DSHOT.

If there is still no reaction, go to Outputs page, flick the switch to agree the security warning and turn throttle up CAREFULLY. It’s best to do this without a prop. If you have a prop it will likely spin.

Still not working? Check your cabling. Test the ESC with a Servo tester or try with another ESC on the FC to exclude a defective ESC or possible defect FC.

I don’t get any GPS Satellites

Attach Battery to the FC and connect to configurator via a USB cable

Is the GPS symbol in the top bar blue? If yes, cabling is fine and you should go outside to test again. However, if it is red, check your cabling first. Switch RX/TX cables on the FC side. Make sure TX on FC is connected to RX on GPS and vice versa.

Got to the GPS page and look for the value for Total messages. If this number is going up, the GPS is working, you should try outside or near a window.

Still no luck? Go to Ports page and check if the GPS is configured to the correctly, to the UART where it is plugged in.

If the port is correct, try different BAUD rates. Default is 115200. Try to lower it step by step and always Save and Reboot.

If you still don’t get any GPS data or you see a red symbol, try another UART. Ddo not use UART 2, that is for receiver only on most common F3 and F4 Flight Controllers.

Still no link to the GPS module? Most likely defective GPS unit or incompatible, try another one. Recommended is a genuine UBLOX M8N or a BN-220.

My Receiver is not reacting at all

Firstly, check for correct binding and connection;see your receivers manual. You will need to confirm a binding light is on. Then go to here.

Is the correct Receiver Port selected in the Ports page? On F3 and F4 it is most likely UART 2; and because of tradition, by default also on most F7 targets. If you’re uncertain, ask in the group. Once that’s ok, go here.

Is the cabling is correct according to the FC manual? Check at least 3 times before you continue! Go here.

Check Receiver Mode in Configuration page: FlySky, FrSky, Spectrum, TBS and most actual receivers need to be set to “Serial based Receiver”. Continue here.

Set the correct Receiver Provider: FlySky – IBUS, FrSky – SBUS, TBS – TBS Crossfire, and so on. Check the receiver manual

Some very tiny micro receivers, especially for FlySky, only support the PPM analogue protocol. PWM is obsolete these days unless you have a very special FC that supports one wire per channel connection. Most current flight controllers (F4 and newer) don’t support this.

Omnibus often has an SBus tab that you need to solder. It’s tiny. It’s next to the UART 1 pins most of the time.

Check the Receiver tab. Is it working? When you move the sticks are you seeing the bars change on the screen? If no sign of inputs, your receiver is defective or you did something wrong such as the cable is in the wrong port on the receiver, or it’s plugged in backwards. If the input is there but strange, we cover this in the next section.

My Receiver shows strange readouts

If there is one channel that jitters the whole time, you’re likely using a FrSky System and this is your your RSSI value. It does depend on your receiver and on your transmitter settings what channel is used for channel RSSI and if it is active at all.

If the channel order is wrong, you will find that moving a stick on your transmitter moves the wrong bar in the Receivers page. So to resolve this, change the Channel order via drop down list and see if one fits. Note: Default on a Taranis is RETA (Rudder, Elevator, Throttle, Aileron). You should change this in the radio to AETR. There is no option for RETA in the INAV drop down list. You could write a channel order for RETA. But, every time you flash the firmware you’ll be doing it again. It’s best to pick AETR, TEAR, or one of the other channel orders in your radio. Then you’ll never have to worry about it again.

If this does not help, reset the plane profile to default on your transmitter. The most common problem is that you set up the transmitter for a flying wing or V-tail. You shouldn’t do any mixing on the transmitter when using INAV. Yes you can fix this, but it’s often faster to go into your radio and set up a new model. Even if you are flying an elevon model, with no rudder; use a default setup with a plane that has Aileron, Elevator, Throttle and Rudder. This seems counter-intuitive. But, when you select a mixer in the mixer page, the flight controller decides how to handle your plane. You will need to get used to the idea that the flight controller, not the radio, does the thinking for you. We also don’t use radio trim once a plane is fully tuned in INAV. 

Still no luck? You can set a manual order. Check what stick axis does move what channel (1-4) on this screen. Then manually write your mapping in the top line.

Aileron, Elevator, Throttle, Rudder, is the default order used by INAV.

Some Pre-Arm Checks fail, what can I do?

UAV is levelled

This should be self explanatory. By Default, the pitch and roll level must not have more than 25° angle, compared to flat level. This is very important for copters but can be changed to 180° for fixed wing to allow easy arming when carrying.

Run-time Calibration

This is the boot-up calibration and self-test of all sensors. Especially for the Gyro that is calibrated to zero on every boot. To get that checked, do not touch the plane/copter after plugging in the battery, for a few seconds, until you here the 3 beeps via buzzer or at least wait 5s without touching. It is possible for something to get corrupted in the firmware of your flight controller. If this warning never goes away, no matter what you do, it’s time to flash the firmware again.

CPU Load

If the CPU load is too high to keep the loop time constant or it is fluctuation too much because of sensor issues, this will inform you. Lower CPU load by lowering loop frequency or disable unnecessary sensors. The ARM processor in the Micro-controller is far too strong for your flight controller. The amount of processing required is far too simple for it. If you see this error and lowering the loop frequency doesn’t fix it, yes, re-flash the firmware.

Navigation is safe

This pertains to any GPS related issues. No fix- You’re indoors you may not see satellites. You need to see six of them, at least. GPS communication errors and so on.

Compass Calibrated

Invalid Compass readings, calibrate it correctly. Be Careful: NEVER 100% trust this check! Better to do one calibration more than one too few and lose your plane in RTH. Or just don’t use it if you have issues. It is not needed on planes.

Accelerometer calibrated

Self explanatory. Do it outside of the plane and as precise as possible. You will never need to do again if you save your calibration values from CLI.

Settings Validated

If you update to a new version, this could be triggered if some parameters have changed or settings become invalid. Check CLI “STATUS” to see if there is an issue or reflash and reconfigure from scratch.

Hardware health

Any Sensor is configured but not available or has bad readings. Check CLI “STATUS” for details.

Further assistance

INAV has a fairly steep learning curve. We all get stuck once in a while. There are a three things you should check before asking for help:

Are you using old and potentially damaged parts?

A lot of quad guys have tons of parts sitting around from crashed quads. This helps to keep the cost of the hobby down which is a good thing. Before you start installing these parts, set up the receiver, speed controller, motor and servos and make certain that they are all working. If you plan on flying a fixed wing you really need to own a servo tester. They are usually less than $10. Sometimes servos are bad from the factory. You need to check the full movement of the servo and insure they are smooth. Broken teeth in the servo gear are fairly common in plastic gear servos. Some of the Hitec servos have replacement parts. Most don’t. When they fail, and you really aren’t in a position to fix them you simply throw them away. Cut off the servo wires before you do, you can use them.

The motors often have bearings that can be replaced, there are good videos on how to do this. Since most motors are cheap these days not many people are rewinding the coils anymore. They are also disposable.

Speed controllers sometimes burn out. Some people have been known to fix them. If this is your thing, go for it. Otherwise, they are usually disposable as well.

GPS units sometimes die in a crash or go bad due to bad wiring, throw them away if they fail.

When you get into a build, please fully check out your hardware before contacting others for help. Also check your wiring. Sometimes when tying down cables the wires get pulled and shorted.

What version of the configurator are you using? 

INAV has different versions of the configurator. You need to be using the same version of the configurator as the firmware. At least to the first sub-version. For example, if you have firmware 2.4.0; you must use a configurator that starts with 2.4, usually the latest version in that group. The most current version can be found here.

Even if you can log into your flight controller without issue on an older version, you should still update to the latest version. Sometimes there are configuration issues that have been addressed in the newest configurator. One other thing, when you flash INAV, be certain that you reboot your PC and try and plug your USB cable into the back of the computer. Do a full chip erase. The stand alone (not the Chrome extension) program is often the newest configurator. You will need to launch this program from your computer, not Chrome.

See if you can find your issue here:

Note about Clone Flight Controllers

We often steer people away from large, expensive planes for their first builds. We have a list of suggested first build planes because they can withstand a bit of abuse as you are figuring things out. INAV has a list of supported boards. There is a list of supported boards that the people at INAV have tested and have found to work. The ones they have links to are boards they have tested and have faith in. When you click through and buy from their vendor, INAV gets a piece of the sale. You are helping to support INAV.

There are many clones in the market. Clones are iffy. Some are okay, many are not. Very often the issue is that the 5v BEC will fail if it’s built into the board. You are running clones boards at your own risk. If you are getting strange problems, take a moment and go to the vendor page of the flight controller you purchased. They will list the legitimate vendors. Go back to where you purchased your board, read the ad again. If it says “Raceday (or whatever) Matek F405 Wing, you have purchased a clone. One of our members lost a $400 plane, because his 2 month old clone F405-Wing board lost it’s +5V. He had no control as it crashed into the ground. His plane weighed 7 pounds. He’s lucky he didn’t injure anybody create property damage.

Asking the community for help – INAV Fixed Wing Group

When you ask for help please provide the following information

  1. What flight controller you’re using? Is it a clone?
  2. Which plane it’s going in?
  3. What version of INAV are you running?
  4. What version of INAV Configurator are you using? It’s in the top left corner.
  5. Have you checked all the parts before installing them to ensure they work?
  6. Have you checked your solder connections under high power magnification?
  7. You have followed the setup guide for INAV Fixed Wing?

When you describe your problem, be specific.

Example of a bad question

Help, my motor won’t spin?

Example of a good question

My motor won’t spin. I have an F405-Wing, it’s going in a Mini Drak. I am running INAV 2.1 and my INAV configurator is 2.1.4. I’ve checked all the parts before installing them and they worked. I have triple checked my soldering and I have built other INAV planes before. But, I did check the guide to make sure I didn’t overlook anything. I have enabled the servos and motor and have looked in the troubleshooting guide. I’d appreciate any help.

Often, someone who can help you will read the top post but will lose interest. Its quicker to reply if we don’t have to get all this information out of you, and the thread is 20 replies of information finding. So, the best thing you can do to get help is to be specific about your problem at the top of the post.

What if we can’t help you?

Go here and file a support ticket.