Something important to new drone pilots, as well as even seasoned veterans, is the inclusion of return-to-home features.
Return to home may initially be an afterthought in the minds of some drone pilots or even go unnoticed by others.
Regardless, return-to-home is an essential technology, aiding in the safe return of your drone in a variety of conditions and situations.
The Air 3 has the latest in DJI’s return-to-home (RTH) technology. We’ll take an in-depth look at the various return-to-home features and discuss how to set them up in the DJI Fly app. With the proper settings, the Air 3 has an added layer of protection should mid-flight difficulties arise.
To help, we’ve identified and reviewed the best drone courses for beginners and professionals.
What is Return-To-Home (RTH)?
In simple terminology, return-to-home, referred to as RTH, is a function in DJI drones that literally returns the drone to the previously recorded home point, without further input from the drone pilot.
Various events will trigger RTH to engage and autonomously bring the drone home. These are:
- Physically initiating Smart RTH by pressing a button on the remote controller or within the DJI Fly app
- When low battery power is detected
- Loss of control signal between the drone and remote controller and,
- Loss of video signal
The home point of the drone is determined using GNSS or the Global Network Satellite System.
Once the DJI Air 3 receives a strong to moderately strong GPS signal, the home point is locked into that location and can then proceed to launch safely.
If there is not a strong enough satellite link, then the Air 3 will not record a home point. This could be due to various reasons.
A common reason is magnetic or metallic interference in the immediate area, oftentimes caused by manhole covers and the rebar in parking garages.
If this happens, the Air 3 should be moved away from that immediate area.
Once the home point has been recorded, there will be a voice prompt from the DJI Fly app alerting you that the home point has been recorded.
Although you can launch the Air 3 before the home point is recorded, it is not advisable. This is because there could be other factors during flight that will necessitate an automatic RTH.
If the home point is not recorded, your Air 3 might not make it back to your location safely.
Additionally, if you find that you need to update your home point during your flying session, this can easily be done within the DJI fly app, as we’ll discuss at the end of the article.
Air 3 RTH Modes
With newer technology in its drones, like the Air 3, DJI has added more options to its RTH functions, although these might be completely hidden, behind the scenes. We’ll look at all of these.
To get to the accessible RTH options, while on the DJI Fly app Live View screen:
- Step 1: Go into the settings menu in the upper right corner.
- Step 2: Navigate to the SAFTEY tab then go to RTH.
Smart RTH is a mode that can be physically initiated in the following ways:
- Pressing and holding the RTH button on the remote controller, after which it will beep to alert you to the initiation
- Pressing the H on the DJI Fly Live View screen
Smart RTH can also be canceled, mid-flight. Once canceled, control of the Air 3 is regained.
To cancel RTH when initiated:
- Tap X on the Live View screen, or
- Press the RTH button on the remote controller
Augmented Reality (AR)
Something new to the 2023 versions of DJI drones is augmented reality views when RTH has been initiated.
As seen on the screen above, you can now see a virtual H on the Live View screen representing the Air 3 home point, which can be seen in all of the map views.
This is called Show AR Home Point.
Likewise, there is a green path showing what route the Air 3 will take to RTH, called Show AR Return-to-Home route.
When landing there is also a virtual “Air 3” on screen showing where the Air 3 will exactly land. This is called Show AR Aircraft Shadow.
To access, enable, or disable AR options, go to Settings > Safety > AR Settings.
You can then enable and disable the blue sliders.
Smart RTH has variations or subsets to the return-to-home features, depending on the conditions when flying. One such is Advanced RTH.
Advanced RTH is part of the Smart RTH function. When conditions are bright enough for the vision system to “see” where the Air 3 is flying, Advanced RTH will activate.
There are two settings available for Advanced RTH, which can be adjusted when going to Settings > Safety > RTH.
These settings are:
The Optimal Advanced RTH Setting
In this mode, the Air 3 plans the best route for it to get home, regardless of any RTH height options previously input.
It will adjust its height to get above, below, or around any type of obstacle or even transmission signals in the area that could interfere with a successful RTH.
With the optimal setting chosen, the Air 3 will use the straightest and most direct route to return home, to save on battery power, thus increasing the amount of time the Air 3 can fly.
If it is too dark for the Air 3’s vision sensors to see where it is flying, the Air 3 will default to a variation of Preset mode, with its altitude options, seen below.
The Preset Advanced RTH Setting
In this mode, which can be chosen, just like the Optimal setting, at any time, the Air 3 will return home at the height preset initially.
In my case, for the area I was flying, the Auto RTH Altitude was set 30 feet or so above the highest obstacle at my flying location.
The Auto RTH Height will also be used if the Air 3 is in Optimal Advanced RTH when the lighting conditions are too poor for the Air 3’s vision system to see its way home. This is then called Straight Line RTH.
As the name suggests, the Air 3 will hover in place, rotate to point to the recorded home point, and then fly directly towards the home point at the designated RTH altitude, if lower than the preset altitude.
If higher than the Preset, the Air 3 slowly descends to the preset altitude as it makes its way to the home point.
Because the vision systems cannot scan the area, the Air 3 could collide with obstacles. Because of this, it is imperative to set the RTH altitude higher than the tallest objects around you.
Low Battery RTH
For Low Battery RTH, the Air 3 will calculate if it will be able to return to the home point based on the current distance of the Air 3 from the home point and how fast it is flying.
You can see how much battery is left remaining, in real-time, on the Live View screen.
By pressing the battery percentage/time remaining area, you will be presented with the approximate time RTH will be initiated due to low battery.
Unlike the previous DJI Go 4 app, the DJI Fly app will not allow you to specify the battery depletion level you’d like for RTH to kick in. It is programmed in.
Once the battery has gotten to a point where safe RTH will be impossible shortly, you will be prompted to RTH. You can cancel the auto RTH within 10 seconds of the prompt.
This is useful if the drone is nearby and you can safely fly it back to your location.
If RTH is canceled and the battery is in danger of completely depleting, the Air 3 will immediately land itself, wherever that might be.
Even if in the middle of a lake or tree-lined forest.
If the Air 3 depletes all battery power while trying to land, it will simply fall out of the sky and crash. Because of this, it is advisable to follow RTH prompts due to low battery.
Failsafe RTH actions should be set by all drone pilots, regardless if new to the hobby, seasoned vets, or commercial pilots doing client work.
Failsafe RTH is important because there are various factors, beyond our control, that could cause the Air 3 to lose signal or disconnect from the remote controller mid-flight.
This could happen even if we have hundreds of hours of flight time under our belts.
The Failsafe options are:
- RTH – The Air 3 will come back to the home point regardless of the surroundings.
- Land – The Air 3 will descend and land, even if the signal was lost over water.
- Hover – The Air 3 will stay in one place until it receives input from you. This could be until having traveled to the Air 3s location and established a connection.
These options can be located in Settings > Safety > Advanced Safety Settings.
Manually setting the Home point
With all of this talk about the Air 3 returning to the home point, it is a good idea to talk about the ability to manually set the Air 3 home point as well.
As we have seen in this article, when the Air 3 and remote controller are turned on, and the Air 3 connects to the available satellites, the home point is automatically set.
There are times though when you might want to go in and manually set the home point.
One example of this may be when flying around a park and you’ve been walking around quite a bit while flying, and you’d like the Air 3 to return to your current location when you hit RTH (Return to Home).
Alternatively, perhaps you are on a boat zipping around a lake or in a bay and would like the Air 3 to fly directly to where you are currently sitting stationary on said boat.
Even though hand-catching on a boat takes serious skill, it can and oftentimes is done successfully.
Two different Home Point options can be manually set:
- Set the home point on the map, using the drag method
- Set the home point to where the remote controller is located
You can get to these two settings by going into the main menu, then Settings > Safety > Update Home Point.
For the Map Drag Method, tap the location arrow and then simply drag the map to where you’d like the H (home point) to be:
For the Remote Controller as the home point option, select the icon for the remote controller: