The scary things that can happen if you fly a drone over 400 ft

in the drone community, there is a lot of talk of the 400-foot rule. The 400-foot rule is because you can only fly your drone in uncontrolled airspace below 400 feet above the ground in America. However, depending on your local regulations and the flight rules in your country, you may fly above 400 feet without breaking any particular rules or regulations.

If you fly over 400 feet, you risk getting caught and being fined or prosecuted. The cruising speed of manned aircraft is approximately 500 feet, so you risk collision by going any higher than this limit. You could also lose contact with the drone at high altitudes.

Also, there are logistical reasons for staying under 400 foot including staying in line of sight and making sure your drone does not lose signal at higher altitudes.

Many drones can fly much higher than 400 feet, and the drone is unlikely to stop you from flying above this limit. Compliance with this rule is up to the pilot, and it can be hard to find a drone pilot and prove beyond all reasonable doubt that they were flying too high.

Can you fly a drone higher than 400 ft?

Many commercial drones can easily fly higher than 400 feet. Drones do not actively stop you from flying above this limit unless you have a maximum altitude level set.

Here are some of the highest flights that have been achieved and posted on YouTube.

Drone and linkHighest flight
Parrot AR drone473 m, 1000 feet
Self-made drone33,000 feet
First-person view drone3000 m
DJI Mavic Pro Platinum8000 m
DJI Mavic Pro8200 feet, 2500 m

The height of the drone flight is recorded relative to its takeoff location. That means that your absolute height above sea level may be much greater than 400 feet, but the drone will measure its altitude in terms of its location above ground level.

This reason is also another way that you can fly 400 feet above sea level. However, you should never fly 400 feet above ground level for the reasons we will discuss below.

Do drones stop you from flying higher than 400ft?

On my DJI drone, you can set the maximum altitude to help you comply with the 400-foot rule. If you try to fly beyond the maximum altitude set in the software drone will warn you, and it will not respond to any further instructions from the joystick to gain altitude.

On the DJI system, the maximum altitude is set at 120 m or 400 feet. The DJI system will allow you to change the maximum height to 500 m. This change will prompt a confirmation box that will require you to accept all responsibilities related to the change of altitude limit.

Other drone brands also allow you to change the upper limit. For example, Autel drones can go up to 800 m.

This limit is measured against the altitude of the takeoff location, which is always assumed to be ground level. Therefore, the figure you see on your display will be the height relative to your takeoff altitude. This height may be much greater than 400 feet if you have taken off in a high altitude area.

Should you fly a drone higher than 400 ft

Just because you can fly at altitudes greater than 400 feet, it doesn’t mean that you should be flying at this height.

The cruising altitude of manned aircraft can be as low as 500 feet. The 100-foot difference between a manned aircraft and a drone limit is enough to provide a buffer to avoid a collision.

Some people who are professional drone pilots may be required to fly the drone at heights of greater than 400 feet. In this instance, they will have to contact the appropriate governing bodies to provide a flight path and flight plan to be aware of drones flying in the area.

Hobby drone pilots do not often perform this level of planning, so you should fly below 400 feet.

Even though the airspace is relatively quiet and the chances of running into an aircraft are incredibly low, a collision between a small aircraft and a drone could be fatal for the pilot and passengers.

I can assure you that nothing above 400 feet is particularly interesting or worth the risk for hobby drone pilots.

Besides the risk of crashing into an aircraft, some other risks associated with flying your drone too high are shown below.

What are the risks of flying your drone too high?

Here are all of the things that can happen if you fly your drone above 400 feet.

Crash into an aircraft

The lowest but most catastrophic risk comes from the collision of your drone with a manned aircraft. Whether or not it is an aeroplane, helicopter, or other aircraft.

Even though the chances of coming into contact with a manned aircraft is relatively low, the potential outcome of the collision could be catastrophic.

Many jurisdictions dictate that you should land as soon as possible if there is an aircraft in the area. I have been flying my drone several times, and I have heard a helicopter or aircraft in the distance. There is always a thought in the back of my mind that it will be alright and I should continue my flight. However, the reality of a potential collision is real and could be fatal.

It is this reality that always forces me to return to my takeoff location.

It is unlikely that a drone would take down a large commercial aircraft, but smaller single-propeller aircraft can easily become damaged. These are the sorts of aircraft which a drone is most likely to encounter at lower altitudes because they are often used for sightseeing and joyride adventures.

Getting caught

It is possible that if you fly your drone too high, you could get caught breaking the law, and you may face criminal prosecution.

Many countries take the breaking of aviation law very seriously because of the potentially catastrophic outcome of a collision.

Getting caught will rely on a law enforcement officer to track your drone and confirm that you were flying above the 400 feet limit.

The thing about flying a drone is that it is very difficult to identify the pilot of a drone until it lands.

Can you get caught flying a drone too high?

There is no current way for law enforcement officers or the FAA to monitor if a drone has been above the altitude limit. They must also identify the pilot, which can be relatively tricky to do.

Drone pilots can fly their drone a significant distance away from the remote control, and a law enforcement officer may not identify who is flying a drone if there are many people around.

Given that it is hard for any law enforcement officers to know exactly what height you have been flying your drone without specialised equipment and that it is hard to track down a drone pilot who is knowingly breaking the law, it is unlikely that you will get caught flying a drone too high.

It is not until something serious happens that there is enough motivation for officers to track you down.

You can get away with a warning for any drone infringements you are caught committing most of the time.

Remaining polite with any requests from officials and apologising, and removing your drone from the air is the best way to avoid any hassle while flying. This advice is particularly true even if you think you are in the right.

Losing signal

If you fly your drone above 400 feet, it is also possible that you can lose your drones signal.

Even though drone manufacturers state that the drones can fly anywhere between four and 10 km away from a controller, the real distance depends on many other environmental factors.

Losing drone signal is a common issue when flying a drone, and I have discussed it in my YouTube video below.

There are a few things that can happen if your drone goes out of range this includes:

  • return to home – modern drones will automatically return to home if they lose connection with the remote control. Check out any of the YouTube videos above for an example.
  • Hover and hold altitude – this is where the drone loses complete connection with the remote control. It simply hovers where it lost signal and will hold its altitude until it gets to 10% of battery, and it will automatically land.
  • Crash land – if your drone runs out of range and tries to return home along a dangerous path, it could crash into something on the way home. Alternatively, it may simply run out of battery and crash land without doing a controlled descent.

High unpredictable winds

As you fly your drone higher, the opportunity to encounter unpredictable wind patterns increases.

If you fly your drone above 400 feet, strong winds could likely disrupt your flight and blow your drone off course.

The likelihood of your drone being blown off course increases if you have a small drone with limited power output potential. Small drones such as the DJI Mavic mini are more likely to be affected by high winds.

Because the maximum altitude is recorded relative to the ground level, the real altitude you are flying relative to sea level may be significantly higher than expected.

If you want to know more about the best drones for high winds, you should check out my other article – where I go through everything you need to know.

Best drone high winds

I have collated the top speeds and maximum wind resistances of the best drones currently available on the market in the table below. This table includes consumer-level drones and professional drones, which Hollywood films used to film their amazing footage.

DroneMaximum speedWind resistance
Mavic Mini13 m/s8 m/s
Mini 216 m/s10.5 m/s
Mavic Air 219m/s10.5 m/s
Mavic Pro Platinum18 m/s10 m/s *
Mavic Air19 m/s10.5
Parrot Anafi1514
DJI inspire2510
DJI Phantom 4 Pro V2.02010
DJI Phantom 4 RTK3118*
DJI Matrice 300 RTX2315
Autel Evo 2 Pro2017 -20 m/s (Force 8)

*calculated 2/3 maximum speed

Colder temperatures

The various metals and composites used in a drone construction respond differently to temperatures because of their specific heat capacity. If the temperature of the surroundings drops dramatically, the metallic parts of the drone will also reduce in temperature quickly.

If this corresponds with a high humidity area, a significant amount of moisture can collect on the drone surface and the surface of the electronic components.

Humidity changes significantly as you fly higher. The relative humidity can become greater as you gain altitude because you enter areas where clouds form. But, in general, it becomes less as you ascend to higher altitudes. Most of the water vapour is at lower altitudes.

The relative humidity is about 78% near the earth’s surface and about 44% at 4.2 km up.

Temperature also plays a huge role in determining relative humidity. The colder the air, the less the air can hold onto moisture, so higher humidity results.

As you are flying your drone higher and higher through varying humidity, you run the risk of having water condensate on the electronic components of the drone as well as on the inside lens and camera.

Flyaways

Flying your drone above 400 feet means that you are unlikely to be able to maintain a direct line of sight throughout its entire flight.

Drones get incredibly difficult to see if they are flown above the 400 feet limit.

It is very easy to get confused and disorientated if you cannot see the drone in the air. In many jurisdictions, the rules stipulate that you should fly a drone in line of sight, ensuring that you have complete control of the drone.

Flying out of the line of sight is tricky, particularly if you are using goggles to fly. For many drone flyers, goggles are not a requirement of flight, and so a line of sight is easy to achieve at all times.

I think there isn’t a drone flyer who hasn’t been tempted to fly behind something or just slightly out of the line of sight. I know that sometimes trees get in the way of my drone flying plan. However, you should minimise how often you fly your drone out of the line of sight, and that full significantly decrease the likelihood of a flyaway.

The good thing about having a line of sight at all times means that even if your camera feed gets interrupted, you can still fly the drone toward yourself.

Summary

In this article, we have gone over everything to answer the question: What happens if you fly a drone over 400 ft?

There is often nothing stopping a drone pilot from flying over 400 feet other than the laws and regulations that need to be self-imposed while flying your drone.

The chances of coming into contact with an aircraft are low, but the outcome is incredibly dangerous, and therefore the risk is high.

Besides aircraft collision, you will likely lose your drone’s direct line of sight. Higher winds and humidity could impact your drone, and you may also lose contact with the drone due to interference or other communication issues.

Be safe while flying your drone, and I highly recommend you stick to all local laws and regulations for the drone’s well-being and avoid any criminal prosecution, which can stay on your record for a very long time.

The Author

Dr Andrew Stapleton is a writer and YouTuber with a PhD in science. He has written and/or produced videos for Science Alert, COSMOS magazine, and Australia's Science Channel among others. Andy started droneflyingpro.com to share his love and the research of all things drone! He has been a drone pilot for many years and has flown many types of drone. His favorite is still the DJI Mavic Air for the portability and functionality packed into a small and portable drone!