
Rules explained
When to use a flight termination system
Drone operations are divided into two categories: Open and Specific. The Open category is for smaller drones flying within visual line-of-sight and below 120 m. Operations in this category do not require authorization from the authorities. If any of the limitations of the Open category are exceeded, the operation is a Specific operation. This does require authorization, which is based on a risk assessment made by the drone operator. The assessment is done to demonstrate that the operation is sufficiently safe. This includes describing the method used for avoiding a flyaway, also known as containment measure.

​Let us take a look at this risk assessment.
SORA
The SORA (Specific Operations Risk Assessment) is a guide for making a risk assessment developed by JARUS (Joint Authority for Rule-making for Unmanned Systems), a global non-government organization with a mix of industry experts and aviation. The SORA contains ten steps, one of which is detailing compliance with the requirement for containment. SORA 2.0 was published in 2019, and containment is addressed in step #9. This was followed by an updated version 2.5 in 2024, where it is step #8.
In the EU, SORA 2.0 was implemented as a regulation by EASA in 2019 as part of Regulation (EU) 2019/947. Consequently, the SORA 2.0 containment requirement is legally binding in Europe. Outside the EU, most other countries have not (yet) implemented the SORA as a regulation. Nonetheless, many of these countries use the SORA as the primary guideline for higher-risk operations, often as de facto regulation.
Containment
Let's look at this illustration of an operational volume from the SORA to understand the containment requirement that applies to all specific category operations.

The operational volume is composed of two parts. The flight geography is where the operation is intended to take place. The contingency volume allows for a temporary breach of the flight geography in case of minor problems, such as using a wrong flight plan or pilot distraction. The SORA containment requirement states that the operator must always be able to stop the drone from leaving the operational volume. This can only realistically be done with a flight termination system.
During any operation, a drone can experience all sorts of malfunctions. Most of these will end the flight quickly, such as engine, battery, or structural failure. However, a small subset of malfunctions will not result in a crash. For instance, if there is a partial malfunction in the autopilot, causing the command and control part to be lost, but the stabilization of the aircraft is still operational. In this case, the drone keeps flying without any control from the remote operator. This is called loss of control or, colloquial, a flyaway.
The operational volume is surrounded by the ground risk buffer where it is permissible to crash the drone. This allows the operator time to activate the flight termination system in case of a flyaway and still be within an authorized area. The size of the ground risk buffer must be determined before the flight and should be wide enough to ensure that a terminated flight will impact the ground inside it.
So, let’s summarize what we now know
To obtain flight permission for Specific operations, the containment requirements in SORA and EU regulations must be met, essentially meaning being able to terminate the flight. Often, a flyaway is the result of malfunctioning avionics, and therefore, the flight termination system must be reliable and entirely independent of autopilot, radio link, ground station, etc., which brings us to the last part: Quality,
Why use a high-quality flight termination system?
The SORA 2.0 containment requirement is written relatively short and without much guidance, so it can be challenging to understand and apply to a given operation. The requirement is also very rigorous in terms of quality of design and implementation, to the point where most operators cannot comply. The SORA 2.5 containment requirement is more elaborate but still requires rigorous documentation. Our Beyond system is designed to meet these stringent requirements. And to make it easy for operators, we provide documentation and recommendations for operational procedures and arguments for compliance, ready to use in the operator’s manual.
MoC 2511
In the EU, EASA has provided an “alternative” by issuing an MoC (method of compliance) called "MOC Light-UAS.2511". It is essentially a step-by-step methodology for having a compliant flight termination system, which, unlike the SORA, has no quality assurance and relies solely on verification tests for compliance. The idea is to make it easier for specific operations to meet the containment requirement. However, it only applies to lower-risk operations; aircraft below 3 m and up to SAIL II.
As a company dedicated to drone safety, we believe that when operating drones that could pose a risk to third parties, we have not only a legal but also a moral obligation to hold ourselves to the highest safety standards. We also believe that over the following years, we will see more companies than ours designing and selling flight termination systems that meet the SORA standards, helping to make them available for everyone everywhere, and that, in time, hopefully, this higher safety standard will apply for all specific operations all over the world.