XPONENTIAL: Looking ahead to a BVLOS framework

AUVSI’s big XPONENTIAL conference is continuing for another day. We took in an expert panel discussing the challenges – and the promise – of Beyond Visual Line of Sight.

Most of us are familiar by now with the term Beyond Visual Line of Sight. It refers to flying an unmanned aircraft beyond a distance where the pilot can still see it with his (or her) naked eye. Without specific regulatory permission (a waiver, certificate, or other authorization), this kind of flight is not allowed. But it is coming on a wider scale and will at some point be considered routine.

An XPONENTIAL panel of experts discussed how we get there…from here.


Start chatting with someone in the know about where drones are headed, and it won’t be long before you hear the acronym, which is pronounced “Bee-vee-loss.” It’s on the radar because solving the BVLOS issue will eventually open the doors to long-distance drone operations, including the delivery of medicines and other critical supplies, as well as surveillance, infrastructure monitoring, mapping, and more.

But it’s not just a wave of a wand to get there. A lot of people have been examining this issue, trying to come up with a model that – with luck – might be standardized globally. Once that standard arrives, it will unleash the floodgates for many drone service providers, eager for the business opportunities that will be able to commence.

Risk mitigation

Regulators are always walking a fine line, balancing innovation and industry needs against potential risks. Specifically, regulators want to avoid conflict with manned aircraft as well as with people on the ground. Often, they’re looking for redundancy features and other failsafe mechanisms, such as parachutes or detect-and-avoid technologies, that would help to mitigate potential risk.

Plus, of course, there are tons of other things that get layered into any risk assessment process. What are if being flown over? Is it rural or urban? How long is the flight? Will it cross busy roadways? How heavy is the drone and payload…and more.


With that background, you can see it’s a very big topic. But BVLOS is also an issue that regulators and the industry are determined to crack. As Andy Lacher, Director of Aerospace Systems Research Center Noblis put it: “The great unlock is the ability to be able to operate beyond line of sight.” But, he cautioned, “It’s not easy…and standards will be a critical component in enabling the future.”

That’s an important distinction. At the moment, companies and organizations seeking permission for BVLOS flight, as a general rule, need to seek permission from the airspace regulator in the country where the operations will take place. At the moment, these applications are carefully considered on a case-by-case basis. Want to fly a single, short mission in a relatively sparsely operated rural area? Doing so with a stable platform and additional failsafe/redundancy? Odds are, if you’re experienced, you’d likely get permission. But this becomes an entirely different matter if you want to fly a payload over a congested urban area.

That’s why a model that incorporates standards would be useful and why a subcommittee at ASTM International has been trying to come up with suggestions for those standards.


Formerly known as the American Society for Testing and Materials, ASTM is a volunteer body that tackles standards. Wikipedia describes it as “an international standards organization that develops and publishes voluntary consensus technical standards for a wide range of materials, products, systems, and services.”

Many of the standards around today, including best practices in manufacturing the personal protection, originated through ASTM. At least two members of the XPONENTIAL panel are on an ASTM committee (AC 478) that’s preparing a report on a proposed framework for BVLOS flight. The goal is for a set of “robust standards” that will enable BVLOS in the future. As moderator Adam Morrison put it, that committee hopes to create a framework that is “flexible and is modular and can accommodate a rapidly changing industry.”

20 Functions

Morrison, whose day job is the CEO of Streamline Designs, LLC, outlined 20 essential functions related to BVLOS flight. He said the list of 20 is highly condensed from all of the factors the committee has been examining but does cover the key areas. Here’s the slide Morrison presented, which outlines the functions that may be required.

It’s worth noting that the panel used BLOS rather than BVLOS; it helps signify that “Line of Sight” could refer, for example, to the range of radio telemetry or other variables beyond the visual sight of the pilot:

So there are a lot of factors that need to be considered.

“It’s not one thing that makes it hard; it’s all these things that make it hard,” observed Andrew Lacher of Noblis.

The challenge

As noted, the challenge for regulators at the moment is that the people pushing for BVLOS approvals are not in any way “One size fits all.” They’re flying different missions in different regions with different aircraft and risk profiles. A Transport Canada official on the panel said it’s something his agency struggles with at the moment.

“As we get to higher-risk operations, as we get to the more science-fiction: Urban drone delivery, advanced air mobility, air taxis, the understanding of how we can integrate those into the airspace..and manage that risk in a systematic and sustainable fashion has certainly been a difficult hurdle for us to overcome,” said Craig Bloch-Hansen, TC’s Project Manager for RPAS Technical Standards.

Consensus-based approach

The development of standards, it was pointed out, is a “consensus-based” approach. In other words, the end result is shaped by committees in collaboration with regulators.

Key principles guiding the ASTM Committee’s work on BVLOS (or BLOS) strategy…

“Certainly from a regulatory perspective, easier-to-provide solutions that have industry consensus standards – it’s a lot easier for regulators than a one-off solution,” said TC’s Bloch-Hansend.

In other words, it’s better to develop a framework – and hopefully, one that can be embraced internationally – as this issue moves forward. “…With a robust framework…We have a much better platform to quickly adopt new technology and new operations” going forward, explained moderator Adam Morrison.

What’s next?

Well, sometime later this year, the ASTM Committee will release its report, which will hopefully provide a workable framework to continue pushing the needle. Regulators will continue to approve (or deny) BVLOS applications in the short term based on risk assessments and other factors.

But the panel did make it clear: Standards that simplify this process, where every participant understands clear guidelines, will only streamline the process. And it’s only a matter of time before they’re here.

FTC: DroneDJ is reader supported, we may earn income on affiliate links

Subscribe to DroneDJ on YouTube for exclusive videos

Load more...
Show More Comments