SORA 2.5 assessment: calculated from the text, step by step

A SORA is demonstrated, not filled in

In the specific category, outside a standard scenario, the operator applies for an authorisation. To obtain it, they assess the risk of their operation with SORA, a method published by JARUS. The authority does not judge good intentions: it checks every level claimed, table by table.

Since 30 September 2025, EASA has applied SORA 2.5 as an acceptable means of compliance with Article 11 of Regulation (EU) 2019/947. SORA 2.0 remains in force during the transition, under another name (AMC1bis). The two versions do not give the same result.

A gap you can measure

Take a drone under one metre, in visual line of sight, over a city, at 120 m, in class G airspace, with two mitigations ticked. Waypoint360's old simplified method gave SAIL I. SORA 2.5 gives SAIL IV. Three levels apart: that is the difference between an operation that is easy to authorise and one that demands solid evidence.

This finding is what led us to rebuild the calculation from the text, table by table.

The ten steps, in the order of the text

The screen and the PDF follow the steps of SORA 2.5, in the same order:

1. Documentation of the operation: volumes, ground risk buffer, adjacent area.
2. Intrinsic ground risk: the characteristic dimension and maximum speed of the aircraft, crossed with the population density overflown.
3. Ground risk mitigations: M1(A) sheltering, M1(B) operational restrictions, M1(C) ground observation, M2 impact effects, each according to its robustness.
4. Initial air risk: the decision tree of the text (atypical airspace, aerodrome, altitude, airspace class, urban area).
5. Residual air risk, when a reduction is justified.
6. Tactical requirements (TMPR), according to the residual ARC; visual line of sight stands in for them.
7. SAIL, read from the table that crosses ground risk and air risk.
8. Containment: adjacent area, assemblies of people within one kilometre, required robustness.
9. Safety objectives: the 17 OSOs of SORA 2.5, each with the robustness your SAIL requires.
10. Safety portfolio, assembled from the previous steps.

The emergency response plan (ERP) comes on top. Since SORA 2.5, it no longer lowers the ground risk: it is part of what the operator demonstrates.

Every figure cites its paragraph

Each step on the screen and each section of the PDF carry the same reference: “Step 2, intrinsic ground risk, SORA 2.5 §4.2, Table 2”. The authority, or you yourself, can check a figure down to the paragraph. At the next revision of the text, we also know which step to review.

The engine, the screen and the PDF read the same list of steps. None of the three writes its own, so they cannot contradict each other.

A calculation without AI

Ground risk, air risk, SAIL, containment and the robustness of each OSO are calculated by functions that read the tables of the text. The tests replay these tables in full: every cell of the ground risk table, every cell of the SAIL table, every branch of the air risk tree.

AI only proposes the written parts: the description of the operation and the emergency response plan. It decides no level.

The EASA edition, or the JARUS one

The tables are identical in both texts. EASA has nevertheless made a few changes, two of which alter a calculation:

• the 250 g rule, which gives the lowest ground risk to an aircraft of 250 g or less flying at no more than 25 m/s, does not apply over an assembly of people;
• OSO #04 (design to an airworthiness standard) requires a higher robustness from SAIL IV.

The EASA edition is offered by default. You can choose the JARUS one, for example for an authority outside the Union.

Population density, guided input

The population density overflown is the hardest figure to establish. You choose the closest descriptor (remote, sparsely populated, rural, residential, urban, very dense), then adjust the value if you have a population map. Dimension and speed come from the drone's record when it holds them.

What is not available yet

• The detailed criteria of Annex E, OSO by OSO.
• PDRAs: EASA has not yet adapted them to SORA 2.5.
• Population density read directly from an official map.

Sources

• Easy Access Rules for Unmanned Aircraft Systems, EASA: AMC1 Article 11 (SORA 2.5) and AMC1bis Article 11 (SORA 2.0).
• ED Decision 2025/018/R, EASA, 15 September 2025, and its explanatory note.
• JARUS, SORA 2.5, document JAR_doc_25 and its annexes, on jarus-rpas.org, Publications section.
• Implementing Regulation (EU) 2019/947, Article 11.