EVLOS (Extended visual line of sight)

Extended visual line of sight (EVLOS) is a term used to describe a concept used in the aviation industry. It is used to refer to the visual line of sight between an operator and an unmanned aerial vehicle (UAV) or drone that is beyond the line of sight (BLOS). In other words, EVLOS allows the operator to fly the drone beyond their visual range, which is typically around 500 meters, by utilizing additional visual aids.

EVLOS is an important concept because it expands the range and capabilities of unmanned aerial systems, making them useful for a wide range of applications such as search and rescue, surveillance, inspection, and delivery services. It is important to note, however, that EVLOS comes with some limitations and regulations that operators must adhere to in order to ensure safety and compliance.

To understand how EVLOS works, it is important to first understand what is meant by line of sight (LOS) and beyond line of sight (BLOS). LOS refers to the direct visual line between an operator and a UAV, while BLOS refers to any point beyond this line where the operator cannot see the drone directly.

In the case of EVLOS, the operator is allowed to fly the drone beyond their visual range by using additional visual aids such as binoculars, telescopes, or cameras with zoom lenses. These aids allow the operator to maintain a clear line of sight with the drone even if it is flying at a significant distance.

There are several different types of EVLOS systems that operators can use depending on their specific needs and requirements. One example is the use of ground-based cameras or sensors to monitor the drone's flight path and provide real-time feedback to the operator. This type of system is particularly useful for applications such as surveillance or inspection where a high degree of accuracy and precision is required.

Another type of EVLOS system is the use of airborne relays or repeaters, which allow the operator to extend the range of their drone by transmitting and receiving signals from a nearby aircraft or ground-based station. This type of system is particularly useful for applications such as search and rescue or disaster response where the drone may need to cover a large area over an extended period of time.

Regardless of the type of EVLOS system used, operators must adhere to certain regulations and guidelines in order to ensure safety and compliance. These regulations typically include requirements for training and certification, as well as specific operating procedures and safety measures.

One of the key challenges associated with EVLOS is ensuring that the operator maintains a clear line of sight with the drone at all times. This is particularly important in situations where the drone may be flying in congested or urban environments, where there is a higher risk of collision or other safety hazards.

To address these challenges, many countries have developed specific regulations and guidelines for EVLOS operations. These regulations typically require operators to maintain a certain distance from people and property, and to have a clear line of sight with the drone at all times. In addition, operators may be required to obtain special permits or authorizations in order to fly their drones in certain areas or under certain conditions.

Overall, EVLOS is an important concept that has the potential to greatly expand the range and capabilities of unmanned aerial systems. However, it is important for operators to understand the limitations and regulations associated with EVLOS in order to ensure safe and compliant operations. Another challenge associated with EVLOS is the potential for communication disruptions or signal interference. In some cases, the use of airborne relays or repeaters can help to mitigate these risks, but operators must still be prepared to handle potential disruptions and take appropriate action to ensure the safe operation of their drone.

In addition to these technical challenges, there are also legal and regulatory considerations that operators must be aware of when using EVLOS. In many countries, the use of drones for commercial purposes is regulated by government agencies such as the Federal Aviation Administration (FAA) in the United States or the Civil Aviation Authority (CAA) in the United Kingdom. These agencies typically require operators to obtain special permits or authorizations in order to fly their drones beyond the visual line of sight.

In some cases, operators may also need to obtain additional insurance coverage to protect against liability in the event of an accident or other incident. This can be particularly important for commercial operators who may be using drones in high-risk environments or for applications that involve sensitive or confidential information.

Despite these challenges, EVLOS has the potential to revolutionize the way that unmanned aerial systems are used in a wide range of applications. By extending the range and capabilities of drones, EVLOS can enable operators to cover larger areas, collect more detailed data, and perform tasks that would otherwise be impossible or impractical.

Some of the most promising applications for EVLOS include search and rescue, disaster response, and delivery services. For example, drones equipped with high-resolution cameras and other sensors can be used to search for missing persons or survey disaster zones for damage and hazards. In addition, drones can be used to deliver essential supplies such as food, water, and medical supplies to remote or inaccessible areas.

In conclusion, EVLOS is an important concept that has the potential to greatly expand the range and capabilities of unmanned aerial systems. While there are certainly technical, legal, and regulatory challenges associated with EVLOS, these can be managed with careful planning, training, and compliance with applicable regulations and guidelines. As the use of drones continues to grow in a wide range of applications, EVLOS is likely to play an increasingly important role in enabling safe and effective operations.