The Civil Aviation Authority in the United Kingdom’s has just released a policy giving the greenlight for drone flights beyond the visual line of sight (BVLOS) in certain airspace, which the aviation regulator has called atypical air environments.

This policy has paved the way for longer automated flights in drone operations that include infrastructure inspections; wind turbine maintenance, off shore drone operations; and site monitoring missions with drone nests.

An atypical air environment can be considered a volume of airspace where operators can reasonably anticipate there to be a reduced number of conventionally piloted aircraft due to the proximity of ground infrastructure, the CAA said.  

However, as the CAA has indicated, there is no clearly defined airspace that can be identified as atypical air environment for once and all times.

“There is no single definition for an AAE (atypical air environment) however, it can be considered as a volume of airspace within which it can be reasonably anticipated that there will be a greatly reduced number of conventionally piloted aircraft due to the close proximity of specific ground infrastructure,” the policy reads in part, adding that drone service providers have to justify in their applications why the areas they wish to work their drones in should qualify for atypical air environment status.

“An AAE is not a separate airspace classification but can exist within any class of airspace. Operations within an AAE must adhere to all rules which apply to UAS within that airspace classification, including any applicable restrictions.”

It would help though, for drone operators and service providers to understand that a typical atypical air environment is one where the likelihood of an unmanned aircraft coming into contact with other conventional aircraft is between none and extremely low.

According to the CAA, typical areas ore one that fall within 30 metres (100ft) of any building or structure; within fifteen metres (50ft) of a permanent linear structure (such as a railway, road, or powerline); and within the confines of private property at a height not exceeding fifteen metres (50ft); for instance; an industrial site where security personnel can use a drone for perimeter inspections.

“Operating an Unmanned Aircraft (UA) within an AAE reduces the likelihood of a mid-air collision (MAC) between an UA and other conventionally piloted aircraft. This is particularly useful when operating BVLOS outside of segregated airspace without a detect & avoid (DAA) capability.”

Drones have been flying beyond visual line of sight in the UK for the past few years; mostly on medical delivery missions; however, these flights were primarily trials under strict restrictions. 

“As the potential for drone applications continues to expand, our new policy paves the way for new ways drones will improve everyday life,” said Sophie O’Sullivan, Director of Future of Flight at the UK Civil Aviation Authority. “It not only enhances the operational capabilities of drones, but also promises widespread societal benefits across different sectors.” 

The regulator’s new rules include activities where drones can remain at low heights close to infrastructure or near buildings where there is little or no potential for any other aircraft to be operating, the announcement continued.  

The CAA reckons its new policy allows for quick and relatively low-cost inspections of power lines for damage, maintenance checks on wind turbines, and to use drones, known as “flying guard dogs”, to ensure the safety of construction sites.  

“This innovation will help National Grid fulfil its commitment to providing clean, fair, and affordable energy to its customers, while undertaking the immense task of enabling the energy transition,” said John McKenna, CEO of sees.ai, a company focused on the development of autonomous flight systems. 

The regulator reiterated that it remained aware that military, emergency services and infrastructure owners all operate aircraft in close proximity to areas that could be considered as an AAE and can land without permission in the course of their tasking. The general aviation community may also operate from any suitable area of land across the UK, including unlicensed aerodromes, without the need to notify their activity or to be electronically conspicuous.

Which is why – before carrying out a AAE flight and only after a successful safety risk assessment approved by the CAA – drone operators will be required to

• Submit a NOTAM of their intended flight
• Co-ordinate their activity with other users of airspace local to their operations – for example local helicopter emergency medical services, national police air services, model flying and gliding clubs as well as unlicensed airfields
• Be equipped with an ADS-B transmitter and receiver or transceiver utilising 978 MHz/UAT
• When operating in controlled airspace, to notify the relevant Air Traffic Control (ATC) service provider prior to conducting an operation and comply with any conditions specified by the ATC unit
• Be equipped with high intensity anti-collision lighting

These safety mitigations ensure the risk of a mid-air collision of a manned aircraft with a drone flying AAE operations remain extremely small

“However, the CAA emphasises the responsibilities required by the pilot in command of any aircraft to check NOTAMs before every flight, as well as ensuring that if your aircraft is equipped with any form of electronic conspicuity it is turned on and enabled during flight.”