If you spend a lot of money on a new drone, you certainly want to test its limits, yet at the same time, you want to make sure not to go out of range.
But to prevent that, we need to know what happens when a drone goes out of range.
When a drone goes out of range, one of 3 things can happen: return to home, hover on the spot, fly away, or land on the spot. Most GPS drones (DJI) are set to return home automatically when they lose signal.
Drone failsafe is a technology implemented in the drone that helps when you lose control of the drone or are low on battery.
These are the types of failsafe implemented in drones:
The simplest way to find out what your drone does when it loses signal is to do the following:
If you see it raise in the air, don't panic, it will go to a certain height and then return back to your spot. This is a good opportunity to see if you can regain the signal if you turn the controller back on.
All GPS drones have the return to home option. The GPS sets a return to home point after the takeoff, and it can return to it by pressing a button or as a failsafe.
Most drones raise to a certain altitude first before moving back home, to avoid any obstacles in their way. Check out my top drones with the return to home feature here.
The accuracy of most return to home flights is between 1 and 5 meters, and it can be influenced by the number of satellites connected and bottom optical sensors.
To select a drone with a more precise return to home, make sure it has more than the standard GPS satellites and the Russian or European satellite system (GLONASS and GALILEO).
Let's say you're in the critical moment when you notice that you already can't see your drone anymore. What can you do then?
After you lose a drone out of sight, you need to check the camera feed and joystick responsiveness. Press the return to home button if there is one, or move with the controller in the general direction it last flew at to try and find it.
Sometimes you might be able to reconnect the controller to the drone while it's still in the air.
Try to adjust the antennas a bit or move yourself to a better vantage point where you have no obstructions between you and the UAV.
Drones that fly away are usually the cheaper toy drone ones, but why do they do that instead of hovering on the spot or landing?
Drones fly away after losing signal because the last control input before the signal was lost remains active. Another reason for flyaways is a drone carried away by the wind, as it doesn't have a return to home option.
There are also cases of GPS drones flying away from people, but from my experience, the usual culprits are cheap drones $200 and below. Toy drones especially tend to lose signal quite quickly since they are already limited to 50-100 meters at best.
You can prevent bad accidents most of the time by finding the telltale signs of starting to lose connection to your drone, so how can you tell you're losing the drone signal?
Before losing the drone signal entirely, you can see the image feed lagging, the controls are less responsive and artifacts appearing in the image. Most drones also have a signal gauge with 3 bars that reaches the smallest bar when you're close to losing the signal.
While this signal loss can be quite fast, most of the time, it's not instant, as long as no big obstacle like a tree or a building is suddenly between you and the drone. If you notice that the signal strength indicator gets to a dangerous level, don't keep flying further even if the drone's specs would allow it in theory.
Many things can block drone signals in real-life scenarios, including wifi, buildings, trees, or simply a lousy antenna angle.
Most drones lose video signal long before you lose the ability to control them. The video is transmitted in 5.8 GHz, which is a higher frequency and makes it harder to penetrate long distances. The controller signal is in 2.4 GHz, making it able to go longer distances.
DJI Drones can alternate between 2.4 GHz and 5.8 GHz signals while in flight, so they usually have a similar range for both video and controller, which is why you usually lose them both together.
What if you have a drone that returns home, but you want to regain control of it as soon as possible, even before it lands?
Some drones (DJI ones included) will regain the signal entirely after they get back in range from a return to home flight. You can then take control of them and stop the return to home altogether.
Regaining the signal is especially useful when there's a building between you and the drone that exceeds the return to home height.
If the DJI Mini 2 loses its signal, it will raise itself to a preset altitude and automatically return to the home point it initially launched from.
With modern long-range drones, you usually have more range than battery life to complete the entire trip back and forth, so what happens in that case?
When a drone runs out of battery, it will slowly descent and lose power gradually or force an automatic return home. Of course, you will be warned by the beeping controller long before that happens.
Toy drones that don't have a GPS will warn you by beeping the controller when they reach around 20% battery and slowly descending on the spot if you ignore the warnings. You can still control the drone direction even as it's descending, so you can land it in a safer spot.
Modern GPS drones like DJI quadcopters have an advanced system that can detect how much battery you need for returning to the initial spot. So the farther you go, the sooner that warning will be met, making sure you always have enough battery to return home.
The US and many other countries limit all drone fliers to keep every flight in their line of sight, which is usually way below any modern drone range.
This means that by following this line of sight rule, you almost guarantee you're not going to lose signal and risk losing your drone.
There's a common misconception that drones don't come back when in sport mode, and since I tested that with almost every DJI drone and a few others, I can say it's not something you should worry about.
Drones will return to home while in sport mode and sometimes change by themselves in P mode (normal mode) to conserve battery on the way back.
A big influence to drone signal range that many people don't consider is weather, not necessarily a bad one. Things like fog, flying above clouds, and even air pressure can influence your drone range.
One reason you're getting a weaker signal when in a bigger city compared to the countryside is a large amount of wifi interference. This can more than half the maximum range of your drone.
Objects between you and the drone
Expect to completely lose signal if you fly your drone behind a mountain and considerably decrease the range if there are buildings and trees between you and the drone. That's why the range decreases even more in the city, as there are a lot of buildings between. Always try to get a high vantage point like a hill and keep as much space between you and the drone as possible.
Controller antennas not tilted properly
If you have tiltable antennas, make sure you have them oriented to maximize the drone signal. If they're long antennas, keep them perpendicular to the direction of the drone. Make sure to kee the controller towards the direction the drone flew at.
If you want to track your drone after it goes out of range, you need to install a GPS drone tracker on it that works with a phone app.
Make sure you keep your drone in line of sight in the first place and you won't have to worry about losing signal, but if you do it's good to know that most modern drones have failsafe modes for when they go out of range.