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In the past couple of years, drones have advanced technologically, making them safer to use and more beginner-friendly.
A few years back, drones were unsafe to fly by a beginner and would require skill. Drones lacked many safety features while the existing ones were in preliminary stages (e.g., return to home).
In a short time, things have changed a lot. However, you must know which drones are safe to use, the safety features behind a drone, and how to proceed in worst-case scenarios.
Therefore, we will cover everything about drone safety features.
Do drones have safety features? What are their role? #
The majority of drones have safety features, but not all of them.
For instance, FPV drones are the riskiest type of drones to fly, not only because they require skill to fly acro, but if you lose signal, the drone can fall out of the sky.
Well, unless it has a GPS rescue module.
DJI drones proved to be one of the safest types you can acquire.
From the drone’s ability to return home to obstacle avoidance sensors and auto-shutoff after a crash, safety features can aid the pilot and avoid damaging the drone even in the foulest scenario.
Sadly, drone safety features are related to price.
Expect cheaper drones to lack avoidance sensors, whereas more expensive drones are packed with all kinds of characteristics.
Most drones should have accelerometers, gyroscopes, magnetometers, barometers, and GPS to help with safety features, real-time positioning, orientation, hovering, maintaining a specific speed, and returning autonomously.
» MORE: DJI Mini 3 Pro: How to Set Up Safety Features (Video)
Does a drone shut off after a crash? #
One of the basic safety features of a drone is the ability to shut itself off after a crash.
A few years ago, this would be nonexistent. If you crashed a drone, propellers would be damaged, motors could keep spinning with overdrawing current, and the battery could have been wrecked, especially if the drone crashed in the water.
This feature is called auto-disarm.
FPV drones lack auto-disarm features, but pilots have set the arming and disarming function on a switch on the remote controller. Therefore, they will always act accordingly if the drone’s motors are stalling and require disarming.
Don’t expect all DJI drones to have such features. DJI does not share this function on the drone specs or in their manual.
I remember when I landed my DJI FPV drone on a sloppy hill, and it rolled back into the valley. The video and motors were instantly cut to avoid damaging any components. Basically, the entire power was cut from the drone.
So, if you have DJI FPV, I can say the drone will auto-disarm on impact.
The same safety feature should cut a drone’s power if you crash it in the water.
This prevents a short circuit on the main board and avoids totally damaging the drone and battery.
Do drone batteries have safety features? #
This really depends on the drone batteries.
For instance, FPV LiPo batteries have no safety features. Even overcharging (overcurrent) can damage the battery and set it on fire.
That’s why dealing with pure LiPo batteries for FPV drones with no safety features is dangerous for an inexperienced pilot.
These are like ticking time bombs if not handled with care. There were many reports of drones starting a fire because of the LiPo battery.
DJI, Autel, and other drone companies took a step further to ensure safe charging and use of drone batteries.
That’s why many DJI batteries have safety features such as overcurrent detection, overvoltage, overcharge, low or high charging temperature, and especially short circuit protection.
However, all these features do not protect the battery from a direct impact where it can catch fire.
If you see your drone battery swallow, that’s another sign the battery is in a dangerous state, and it is time to discharge and dispose of it safely.
» MORE: How to Safely Dispose of LiPo Drone Batteries
An overview of safety features found in today’s drones #
Let’s dig deeper into the safety features you can use in many major drone models.
Obstacle avoidance sensors #
Newer drones have anti-collision sensors to slow down, stop, or go around when approaching dangerously close objects.
The technology behind obstacle avoidance sensors has evolved significantly in the past couple of years.
I remember my first drone, the DJI Mavic Air, had some obstacle avoidance, but keeping the drone safe with high accuracy wasn’t that reliable.
It failed many times to avoid obstacles when flying in a forest.
Nowadays, all newer drones with obstacle avoidance sensors will do incredibly well, from the DJI Mini 3 Pro to the Mavic 3 Pro and Air 3S.
What type of obstacle avoidance sensors exist?
- **Ultrasonic sensors: **Functioning like a bat signal or submarine ultrasonics, these sensors emit a sound at high frequency, whereas afterward, it is received and calculates in real time the travel distance. This way, these sensors can create a map of the surroundings and know accurately how far from the drone is an object.
- **Stereo vision: **These sensors have some kind of 3D sensing ability to perceive an object as humans do. The sensor’s accuracy is based on how many pixels it identifies. More equals better.
- **Infrared obstacle detection sensor: **The sensor will emit infrared lights that will fade in distance. The same sensor will perceive the strength of the IR light, whereas if it’s stronger, it means the drone or sensor is closer to an obstacle. If it fades away, no obstacles are recorded by the sensor in the vicinity.
- **Time of flight sensors: **These are more advanced types of anti-collision sensors made of a lens, interface, sensor, and light source. ToF sensors will capture drastic information from an image and work at a high framerate for real-time obstacle avoidance.
Drones can use other types of sensors, but they may be uncommon.
With the technological advancement of drones, anti-collision sensors are core parts of the drone to create a safer environment and protect drones and others.
A few drones, such as the Mavic 3 series or Air 3, have omnidirectional obstacle avoidance sensors, which means they have complete protection from collisions from any angle.
Such sensors can detect objects from a few meters away to at least 40 to 50 meters.
GPS return to home (failsafe) #
In today’s world, almost every drone (at least decent drones and not toy drones) has a return-to-home feature.
A module is installed on the drone that detects its position via satellite GPS, GLONASS, and Galileo in real-time but may differ from one drone to another.
In concordance with this module, the remote controller has GPS positioning, whereas the drone can accurately calculate the distance between the pilot and itself.
This safety feature has the ability to act on pilot input or independently, depending on the circumstances.
You can press a button on the controller to activate the GPS return-to-home function, and the drone will ascend to a specific height set by the pilot on the drone’s settings, follow a precalculated path, and land on the takeoff point it registered by GPS or to the controller’s location.
However, for the GPS to return home, it must acquire satellites.
A drone can decide to return the drone without any pilot input for a few reasons.
Low battery #
The drone detects the battery won’t be enough for a safe return if you continue flying. This is calculated based on the remaining battery and drone distance and can auto-initialize for the drone to return home safely.
The pilot can override the auto-RTH from the remote controller based on low battery, but it is strongly recommended not to.
In contrast, FPV drones do not have these characteristics. You will have to constantly monitor the voltage level (yes, you won’t have a percentage like with DJI drones) and, based on the pilot’s decision, when it is time to land it.
If you don’t land it, the FPV drone will lose throttle power, and the motors will weaken until it slows down to the point the drone can’t be kept in the air and crash.
Of course, because FPV LiPo batteries won’t have any protection, surely they fall below the minimum functional voltage, and most likely, the battery will be permanently damaged.
» MORE: Does DJI Avata Have Return to Home? (Explained)
Signal loss #
If you fly your drone long-range or deal with interference that will cut the video or radio signal to the drone, it will stop in place and hover.
After a few seconds, if the signal is not restored, the drone will activate the auto-return-to-home function based on the same characteristics as mentioned above.
A precalculated path will persist as the drone continues coming toward you (the takeoff point or pilot controller) and the signal is restored.
You can interrupt this function once you have a strong signal and keep flying the drone if it’s safe to.
» MORE: Do Trees Block Drone Signals? (Explained for Beginners)
DJI and other drone companies have built an incorporated mapping system into the drones to limit or block flights in specific restricted zones.
These virtual fences will block a drone from entering or taking off in such areas, for instance, around an airport or military base, which is against federal laws.
This geofencing system significantly decreases the chance of drones entering an airplane’s path or entering restricted military space.
» MORE: Do DJI Drones Have Geofencing? (And How to Unlock Them)
DJI AirSense #
Yet another drone safety feature that can be found in more expensive or enterprise drones is DJI AirSense.
This is the next step in airspace safety. DJI AirSense is an alert system that uses ADS-B technology for enhanced situational awareness, sending data automatically to nearby aircraft.
This feature reduces the risk of collision between a drone and a manned aircraft because the plane can now see the drone on its radar.
Although this safety technology was recently introduced, we should expect to see it more across more affordable consumer drones in the future.
Beginner mode #
Maintaining altitude, speed, and safety can make it difficult for a beginner to fly a drone for the first time.
That’s why DJI has introduced a beginner mode, which is a fantastic safety feature that limits the speed, altitude, and distance a drone can fly.
The beginner mode can be disabled once the pilot has learned the drone’s basic maneuvers and feels confident he or she can safely fly the drone beyond these beginner mode restrictions.
Safety can be improved with mechanical accessories. Let’s cover a few of them, shall we?
» MORE: 27 Best Drone Accessories (I Can’t Live Without)
Drone parachute #
Although uncommon, a drone can be equipped with a type of parachute that will open if something goes wrong and the drone falls out of the sky.
The drone parachutes slow the fall of a drone to protect others and the drone.
Propeller guards #
Attaching propeller guards is a typical mechanical accessory that will increase the safety of using drones in tight spaces or near people.
These guards will protect the propellers from impact and other objects from being touched by the fast-spinning propellers.
FPV has a subcategory of drones called Cinewhoops, which have enhanced propeller guards called duct guards for safer flights.
While propeller guards can be placed on almost any standard drone (different for each model) and taken off at any time, the duct guards of a Cinewhoop are permanently installed.
In fact, the structure, design, and aerodynamics of a Cinewhoop FPV drone are built around its duct guards.
» MORE: Why Does DJI Avata Have Duct Guards?
Water floaters #
The water floater is another mechanical safety device that can be installed on any drone.
Floaters are fantastic if you often fly a drone above the water, especially above lakes.
If the drone’s battery depletes and it lands on the water, the floaters keep it above the water’s surface.
The drone can either remain completely dry or, if it falls out of the sky, it will stay on the water’s surface and can be recovered instead of sinking to the bottom.
Can you override safety features? #
Some drone safety features can be overridden, and others cannot.
For instance, you can change or disable the entire anti-collision sensors from the drone settings.
It would be ideal not to, but if you want to get the drone through some gaps, the obstacle avoidance sensors usually won’t let you.
Another function you can disable is returning to home if you lose signal to the drone.
You can set the drone to hover instead, which is mostly recommended if you fly indoors, so the drone won’t crash into the ceiling.
As mentioned, you can manually override the auto-return-to-home when the drone is on low battery.
However, other types of safety features, such as short-circuit protection or stopping motors on a crash (if they are stalling), cannot be disabled.
» MORE: Best DJI Alternatives – What Drones Are Better Than DJI?