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Drone Specific Category

The Specific Category is the second category according to the classification made in the European UAS regulations. If we compare it with the Open Category, the Specific Category offers us a total paradigm shift that allows operators to carry out operations with very diverse UAS.


It has been created to give drone operators options to do all kinds of operations. It is very broad, since it allows us to carry out low-risk operations (such as flying a drone of > 25 kg in an unpopulated area) or high-risk operations (such as the BVLOS flight of an aircraft in a populated environment).


Depending on the risk of the operation to be carried out, the Specific Category does not offer pre-established requirements that are suitable for all operations. Each UAS Operator has to generate its own operational scenarios. This is fundamentally different from the Open Category.


Now, if we do not have predefined requirements or limits, how should we proceed to prepare for a flight?

Risk Assessment

Any operation that we want to carry out will be subject to a prior risk analysis using the Methodology SORA (Specific Operations Risk Assessment), which will allow us to assess the risk in all phases of the flight and determine what mitigations must be applied to achieve the safety objectives.


Through a SORA, you can obtain a value called SAIL (Specific Assurance Integrity Level) resulting from the combination of ground risk (GRC), air risk (ARC), and its corresponding mitigations applied. Depending on the SAIL index obtained, the operation will be considered more or less risky:


  • Low Risk (SAIL I and II)
  • Medium Risk (SAIL III and IV)
  • High Risk (SAIL V and VI)

Low Risk Operations (SAIL I & II)

Standard Scenarios (STS)

In the lowest risk zone, we find the operations that fit into the Standard Scenarios (known as STS).


The STS are types of operations that have been previously defined by EASA in the appendices of the regulation.


The definition of an STS includes several aspects, such as operational limits (safety distances, flight height, documentation, etc.), training requirements for the Operator’s personnel, requirements for the UAS that must be used, among others.


EASA has established that only C5 & C6 drones will be able to fly in these scenarios. In order for the Operator to carry out flights within the STS scenarios, it will be enough to count with STS Operations Manuals and make an operational declaration (no response or approval needed).


If the intended operation has not been previously generated by EASA in the form of STS, the Operational Authorisation procedure must be carried out (and await its approval) applying and justifying the mitigation measures resulting from the SORA study.

Predefined Risk Assessment (PDRA)

The PDRAs are documents published by EASA that facilitate the Specific Operation Risk Assessment (SORA). This way, UAS Operators only have to carry out the necessary documentation to satisfy the security objectives that are indicated.


Over time, a PDRAs can become standardized in such a way that they can turn into Standard Scenarios.

Specific Operation Risk Assessment (SORA)

If there is no Standard Scenario or PDRA that suits the needs of our operations, we must carry out a risk assessment using the SORA methodology.

Medium Risk Operations (SAIL III & IV)

Operational Authorisation

In this case, the complete work must be carried out to obtain the Operational Authorization. If the result of the SORA (after applying the mitigations) results in a SAIL III or SAIL IV, we will need an Operational Authorisation. At this point, the Competent Authorities will indicate to the operator the possibility of needing to carry out a Design Verification Aircraft.

Design Verification Process

If the level of robustness of any of the OSOs linked with the design is medium (i.e. SAIL III and IV), the national competent authority should require the Design Verification Process of the whole aircraft, or one of the subsystems. Specially if this helps mitigate the risk and reduce the SAIL number by 1 or 2.


This evaluation is a separate procedure through which you will certify that the aircraft meets the necessary specifications to be able to operate safely in the requested scenarios.

High Risk Operations (SAIL V & VI)

When the result of the SORA gives us a SAIL V or SAIL VI after applying the mitigations, we will be obliged to carry out an aircraft certification process according to the Airworthiness standards described in document PART21.


Regardless of the risk of the Operation, for flying in Specific Category, you will need an airspace pre-coordination and a final coordination with all the relevant authorities most of the times.

2 Responses

  1. Thank you for the fruitful briefing on the SPEC flight. According to regulation 847, for the LUC, the operator needs to have an SMS for organizational management. However, the criteria determined in this document (as well as AMC and GM) are clearly taken from manned aviation and do not fit unmanned operations. Do you have any information, workshop output, or any work that indicates what the SMS requirements might be for drone flights, whether VLOS or BVLOS?

  2. Thanks for your comment Selcuk. The answer to this is too long to explain it here. If you wish, fill up the contact form and let’s have a call!

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