What is Beyond Visual Line of Sight?
Beyond Visual Line of Sight (BVLOS) refers to the operation of an unmanned aircraft system (UAS) when it is beyond the operator’s direct line of sight. In scenarios where a drone is out of the pilot’s visual range and there are no trained observers maintaining visual contact, it is classified as BVLOS.
The practical range for BVLOS operations varies based on factors such as the aircraft's size, prevailing weather conditions, and potential obstacles to line of sight like buildings and trees. Despite these variables, some regulatory bodies have established specific distance thresholds - for example, a distance exceeding 500 meters may fall under BVLOS regulations and these flights are likely subject to additional operational restrictions to ensure safety.
Regulatory Requirements in the United States
In the United States, the Federal Aviation Administration (FAA) mandates that drones must remain within the visual line of sight of either the pilot or a trained observer who is in communication with the pilot. Exceptions to this rule require special waivers.
In June 2016, the FAA issued Part 107 of Title 14 of the Code of Federal Regulations (14 CFR Part 107), the final rule for “Operation and Certification of Small Unmanned Aircraft Systems.”, 1 Part 107 set forth requirements for routine operation of small uncrewed aircraft (UA) in the National Airspace System (NAS), but did not include requirements for UAS design, manufacturing, or production. Instead, it limited small UA operations to certain areas (e.g., at or below 400 feet in Class G airspace) and conditions (e.g., operations within visual line-of-sight (VLOS)), with the intent to prevent UA from interfering with other aircraft in flight or posing an undue hazard to people or property on the ground. This rule was a critical step toward normalizing low-risk VLOS small UAS operations in the United States. – from the Final Report issued by the Unmanned Aircraft Systems Beyond Visual Line of Sight Aviation Rulemaking Committee
To operate a BVLOS program, applicants must secure a waiver by demonstrating that their UAS operations will not compromise safety. This typically involves pre-programming the aircraft, integrating detect-and-avoid technologies, and/or implementing safety measures such as geo-fencing and engaging the Low Altitude Authorization and Notification Capability (LAANC) process.
Why Apply for a BVLOS Waiver?
BVLOS operations offer significant advantages over line-of-sight activity by expanding the distance in which a drone can travel. Flying BVLOS offers unique benefits for certain types of security and operational activities:
Public Safety
BVLOS flights enable law enforcement and emergency responders to monitor and respond to security threats remotely. Research from the Electronic Frontier Foundation (EFF) indicates that nearly 1,500 police departments in the U.S. utilize drones, including for BVLOS operations.
Critical Infrastructure
Remote piloting of drones to assist in surveillance for security or maintenance provides regular monitoring of infrastructure systems from a central hub and with minimal staff allocation. Ground-based or airborne radar can help agencies achieve BVLOS.
Scientific Research
Organizations such as the National Oceanic and Atmospheric Administration (NOAA) leverage BVLOS flights to collect atmospheric and climate data at high altitudes, over vast ocean expanses, or near the edge of space.
Delivery Services
BVLOS capabilities allow for the efficient delivery of packages without the need for human drivers to physically transport goods.
Ensuring Safety During BVLOS Operations
Maintaining safety in BVLOS operations is paramount. Radar technology plays a critical role in ensuring safe operation by tracking the aircraft from a distance, monitoring surrounding airspace, and preventing collisions. Airports have long utilized ground-based detect-and-avoid systems incorporating radar. More recently, the FAA has begun approving BVLOS waivers for UAS equipped with integrated radar systems and other safety measures, such as AATI’s AiRanger with integrated EchoFlight radar.
