Getting started with INAV Fixed wing is an overview guide. It will give you a good idea of what’s ahead when starting in INAV. Please feel free to ask questions in the Facebook group if you you need more answers, once you’ve got to the end of this guide.
- What you will need
- Watch and learn
What you will need
Price range $2 – $320, $80 is a good ballpark figure
There are at least a few hundred different planes for sale at any time. One way or another the majority of them will work with INAV. Some are better choices than others when you are new to INAV. A group favorite FPV plane is the Sonicmodel AR Wing. RMRC sell this model as the Recruit. You will want the AR Wing and not the Mini AR. There are many others that can work. If you happen to have an old Teksumo or Popwing, those can work well. Your first plane will probably see some abuse as you figure things out. Don’t let this get you down, we’ve all been there.
The price range is as low as $2 for 2 sheets of Dollar Tree foam and scratch build plans from places like FliteTest. The Drak from RiteWing is $320, just for the foam kit. You can still pay much more for an RC plane than $320. But realistically, There are many great RC plane options for less than $100
Price Range $25-$75, expect to pay around $45
For the most up-to-date list of supported flight controllers for INAV, download the most recent version of the INAV configurator. Look in the Firmware Flasher section. You do not need to have a board plugged for this.
If the flight controller you’re looking for isn’t listed, it will not work with INAV.
The exception to this is if it’s a clone flight controller. If the seller list an INAV target, it should work. However, the reliability of these clone flight controllers is debatable. A group favorite is the Matek F405-WING. It’s a good first flight controller for people just starting out. If you’re not a fan of soldering, the Furious FPV F35 may be a good route to go for a first build. However, you will really want to learn how to solder to progress well in this hobby.
Other good alternatives are the Matek F405-STD or F722-STD, paired with a Matek FCHUB-W fixed wing PDB. Be careful with Matek, there are fake Matek flight controllers for sale. To make sure you are getting a genuine Matek flight controller, visit their web site for approved vendors. You should avoid clone flight controllers and difficult build ones for your first flight controller. You also want a minimum of an F4 flight controller. Older flight controllers from crashed quads aren’t suggested.
Power Distribution Board (PDB)
The Power Distribution Board does exactly what it says; it distributes power. It used to be that you needed to buy a separate PDB to go with your flight controllers. But these days, a lot of flight controllers are all-in-one units, which have a PDB already. In particular the Matek WING and WSE series.
PDBs divide the power up in to separate rails, to power devices with different needs. Some of these rails will used Battery Eliminator Circuits, or BECs to control the voltage. We’ll take a look at some of the different rails now.
VCC or VBAT
This is the full power from your battery pack. When you start a flight with a charged 3S pack, for example, you’ll have 12.6 volts of power. This Voltage will deplete as you use the energy from the pack. On most PDBs these days, a current sensor will measure the current draw over the main battery input. VBAT will be delivered to any components that need it, for example the ESCs.
5 Volt rail
A lot of your devices will be running on 5 Volts, so the 5V rail is pretty important. It will power you receiver, GPS module, LEDs, buzzer, OLED screen, some FPV cameras, plus many more devices. Some PDBs also power the servos from the 5V rail. We will cover servos below, but pay particular attention to the part on Amp draw.
On PDBs designed for fixed wing models, you will find a separate servo rail. This may be fixed at 5 Volts, or selectable up to 7.2 Volts for HiVolt servos. Selecting a higher voltage increases the torque of the servo and the speed. But, make sure to check the specifications of the servos before changing this. Most mini servos that we recommend can happily run on 6V.
You need to be mindful of the servos when choosing your BEC. It is highly important that the BEC has enough overhead to easily cope with the servos that you install in your model. Most models that we fly use mini servos. They’re commonly known as 9 gram servos, even though the weight can vary. With mini servos, you should allow a minimum of 0.75A per servo. so a BEC with a constant current on the servo rail of 3A could run 4 servos. However, if the 5V rail is also powering other things, not just servos, you should deduct 1.5A from the rail rating to cover the other devices.
When you look at the voltage range of a video transmitter, it will list something like 7v to 27v. So, you can just plug in VCC, right? Yes and no. Yes, you can, it will work. No, because we try to get as close as possible to the lower voltage. This means that there will be less energy loss, as the VTx lowers the voltage to power its internal components. Some PDBs have a 9V, some have 10V and some have only 12V. Some you can set the voltage that you want to use.
Price range $10 to $40
The first and most often asked question is “Do you need a compass?” No, a compass is essential on a multirotor. But planes pretty much always fly forward, and thus a compass isn’t necessary. If you have the financial resources the Matek GPS is a great GPS. A group favorite for a cheap GPS is the Beitian BN-220 GPS module. You can find it for under $15, works well with UBLOX7, and supports both GLONASS and Galileo satellites systems. Setup in a good position on your plane this unit can usually find six satellites in under 30 seconds, around a second on hot starts. Many of us in the group use them and can answer questions you may have.
The GPS unit plays an important role. If you can lock in quickly and have it remain locked in, you should be fine. Avoid the older hockey puck style GPS units. They work great. But the large plastic case makes them overbearing. You can remove the module from the case, but they can still be quite large. My two cents? When you’re starting out you don’t need a high end GPS. As long as you find six satellites and keeps locked in you should be fine.
$12-$100, Expect to pay less than $35
Here’s yet another learning experience. The cheap ones actually work, and though they are too slow for quad pilots they tend to work okay for relaxed FPV flying. As you move up in price the image quality does improve and the latency improves. You shouldn’t buy the cheapest thing you can find, and you don’t need the most expensive camera you can find. Something in the middle should be good when you’re first starting. If you’re going to be doing proximity flying in shaded and bright light environments you will want a camera that can handle the transition between light and shade quickly. This is having wide dynamic range. If you’re flying high you can get by with cheaper FPV cameras.
Most cameras come with mounting brackets. But for most kits you don’t need them; the camera just slots in to place. There are also different sizes of camera: Full, Micro, Mini, and Nano. Micros and nanos tend to be very small and some can be delicate. If you’re not building a sub 250g plane, stick with minis.
There are many great video reviews online that go over the image quality of most of the cameras you may be looking at. Lenses come in different physical sizes, and are described by their thread size, such as M12 or M8. These are not interchangeable. However, you can choose different fields of view. A lot of companies give this in millimeters. But, the millimeter sizing varies depending on the camera, so it’s best to find the field of view in degrees on the spec sheet. As a rough rule of thumb, 1.8mm is very wide angle and 2.5mm is a bit more normal field of view.
Video Transmitter (VTx)
Price range $15 to $75, Ballpark under $30
The VTx is an essential part of the flight experience. Though your goal may be long-range FPV. We strongly, and I mean strongly suggest that you stick with a first setup that keeps you within 1km when you’re new. You will need to have a lot of things figured out before you endeavor in long-range FPV flights. A good 5.8 GHz, 600 mW VTx is relatively inexpensive.
Most VTxs are pretty similar in the connections and how they function. But the main thing that you need to be aware of is the connector to the antenna. There are four types that we use in FPV at the moment: SMA, RP-SMA, MMCX, and U.Fl. Ideally go online to learn more about these connectors. Pay special attention to the RP-SMA and SMA connections. They look very similar. But if you don’t keep to the same type of connector, your antenna and VTx won’t actually be connected to each other. This can hoverheat and damage your VTx.
If you are going to be flying with a group of other pilots, they may have some good advice as for work for them. Some of the cheaper VTxs work fine but have limited bands. Some groups may have pre-assigned bands for members and they will be very specific about what channels they want you to use. This may limit your choices to the more expensive VTxs. If you’re flying alone, the world is your oyster.
$50 to $700, expect to pay around $300
You will need something to watch your live video from your plane’s VTX. You can watch from a small monitor or for a better experience, watch from a pair of goggles. Goggles cost anywhere from $50 to $700. DJI has a new line of digital goggles that is receiving rave reviews. They are well over $500. Currently they have no competition in this space. But that will change. The DJI goggles work with INAV, but not with a full-featured OSD like INAV offers.
If I were starting up right now, knowing what I know. I would buy the best pair of analog goggles I can find for under $200. Use them for two years, and then see what’s available when I’m dying to upgrade. Avoid the under $100 pair of goggles. If you go this route, at least get one with diversity. Another thing to note is that with some goggles, like FatSharks, you will also need a Video Receiver, or VRx. This goes in a bay in the side of the goggles. Again, pick a diversity VRx. The best around at the moment is the RapidFIRE module from ImmersionRC. But, you can get some good VRxs for much less. The Eachine Pro58 is a pretty good module, but works better with updated firmware to Achilles. But, that can be a fiddly solder job.
The single most important components in your FPV system are your antennae. You will want something better than the ones that came with the VTx and goggles. There are a couple of things that we need to discuss about antennae that are pretty important. So lets crack on.
There are two types of polarisation on antennae that we can find on RC models. Linear and circular. We don’t need to go deep in to science here. But you need to understand that if you mix the two types, you will suffer a loss in signal strength.
But basically, for linear polarisation, imaging the radio waves travelling along a path from the transmitter to the receiver. They are standing bolt, upright from start to finish. However, with circular polarisation, the radio waves are also spun along the axis of the path. Most of the time with FPV, we use circular polarised antennae.
Circular polarised direction
You may have noticed on circular polarised antennae the letters RHCP or LHCP. These stand for Right Hand Circular Polarised and Left Hand Circular Polarised respectively. This is the direction that the antenna spins the radio signal It doesn’t matter which direction you choose; there are no advantages to either over the other. But, you must choose the same direction for all your antennae. If a lot of your friends fly with RHCP, maybe pick all LHCP antennae for yourself, and you may have a cleaner image.
The final thing we need to look at is signal direction. You may have heard the terms omni and patch in relation to antennae. This is referring to the signal direction. An omni, or omnidirectional, antenna sends out a signal in all directions, like a big doughnut. So with an omni, you could fly behind yourself and have just as good a video feed and in front.
The problem with antennas, is they only have so much signal. So if its firing out in all directions, it has so much range. That’s where patch antennae come in. A patch narrows the spread of the signal, known as the beam width, to get more distance.
There are lots of other things about antennae that we could discuss. But, that could be an article all on its own. when first starting out, these basic principals will help you pick the right antennae for you. You will need to pick an omni antenna for your aircraft, and for the goggles you will need an omni and a patch.
$5 to $200
There is a lot to learn about motors. The more you know, the more you’ll enjoy the hobby. Painting the broad strokes, you need a motor that can deliver enough grams of thrust to push your plane. Motors that barely deliver enough thrust make for a boring flying experience. If you can easily exceed the required grams of thrust you’ll probably enjoy your plane a lot more. You have to worry about the weight of the motor and how it affects CG.
Motors have naming conventions like 2205 and 2826. They also have mentions of KV in the specs, propeller sizes and pitches that work best with various motors. And then there are divisions of motors based on quality. The Racerstar BR2212 is $5 and looks similar to the Sunnysky X2212 V3. The Sunnysky costs a little over 4x more. However, the SunnySky is a much better motor with better bearings. If it’s a plane you’re going to fly a lot, the extra $16 is money well spent. If you’re just starting and feel you need to watch your budget, the Racerstar motors are fine.
(ESC) $10-$70, expect to pay around $20
If you come to us from the traditional RC plane world. You probably know Electronic Speed Controllers like Turnigy Plush. These have the Battery Eliminator Circuit that dish out the 5 volts to run your servos and receiver. They were fine with conventional planes. But as we have more equipment on board now, we should use a dedicated PDB. Remember we spent time learning about PDBs earlier. You can still use the Plush style ESCs on INAV planes, if you eliminate the 5V coming from the BEC.
Many of us now use the BLHeli style speed controllers, that are designed for multirotors. They are pure ESCs, without the BEC. There are 16bit and 32 bit versions. Using your flight controller, you can get into your ESC’s settings. This allows you to do things like reverse the motor direction, add a brake, change the timing, and update firmware really easily. The BLHeli and BLHeli_32 Suites offers a lot of interesting tools to super fine-tune your motor. Another great thing that came along with BLHeli_32 ESCs is telemetry. There is a small wire that can attach to a spare UART Rx pad. INAV can get some real time specs from your motor including RPM and ESC temperature. The BLHeli ESCs are small in comparison to traditional ESCs. In most applications, this is fine. But, if you are going to be pushing the ESC, adding a heat sink and making sure they are in good airflow is not a bad idea.
$2 to $30
Propellers are to a plane is like wine to a meal. You can get by with two-buck-Chuck on a Tuesday night, but for special occasions, you’ll go all out. Being a connoisseur of propellers can upgrade your flying experience. They are something cheap you can experiment with. Propellers are specified by size and pitch. You need ones that work best with your motor and battery combo. Everybody has to burn up at least one motor when they are new, because they drove a prop that is too large for it. Hell, some members are not so new, but still burn motors because they want to push the limits. This is a learning curve. Often the Gemfan APC style props will get you by. But, there are much better ones, including the genuine APC props that so many copy.
Transmitters and Receivers
You can fly INAV with quite a few different systems. We’ve had good luck with FlySky, which is the cheapest way we know of to get a transmitter and receiver working with INAV.
Most of us in the group use some form of OpenTX system. This is an open source firmware for RC transmitters; most commonly found in FrSky, Jumper, and RadioLink transmitters. This is yet another learning curve, but, at least for this, we have help. We have a group OpenTX model which has done nearly all the heavy lifting for you.
There are also great add on modules for long-range FPV such as FrSky’s R9 module and TBS Crossfire. But when you’re first starting, stick with the simple 2.4 GHz. Chances are you’ll may need to go find your plane from time to time, it’s easier to do when it’s closer to you.
Watch and learn
One of the best ways getting up and running with INAV is to do a lot of homework upfront. Sometimes just watching what people say and what they’ve been up to will give you many new ideas. Though you may have a plane for INAV before starting in the group. You should be open to using another plane as your first INAV plane. You can always get back to the plane you currently have. We have no financial interest in the plane you buy, but we do want to make sure you succeed.
The Search Tool
One of the strongest tools we have in the group is the search tool in Facebook. Type the name of a plane you’re interested in and there will most likely be dozens of posts. Often times people will list certain specs which may give you some ideas as how to setup your plane. Even if the post is very old, if you have questions, write a reply in the post. This is the same for problems. If you have a problem, search for that too as there is a good change you’ll find an answer.
Asking for help
Our group strives to help members who are looking to start with INAV, as fast as possible. We love questions. But, there is a skill in asking questions. You want to give as much information as possible in the question so that we know what you’re talking about. Feel free to write it in a language you are comfortable in using, and we’ll translate it and answer it.