Category: Drone Glossary

Operational volume

In SORA, the area that must be technically "included" for safe operation. It consists of flight geography plus contingency volume.

TMPR (Tactical Mitigation Performance Requirement)

Performance requirements for tactical mitigation measures against air collision risks (e.g., detect-and-avoid, cooperative systems, procedures). The TMPR depends on the residual ARC.

OSO (Operational Safety Objective)

Specific security objective in SORA (e.g., relating to technology, operations, people, organization) that must be fulfilled and verified according to SAIL with a defined integrity and assurance level.

SAIL (Specific Assurance and Integrity Level)

SORA outcome level (I–VI), which is determined from the final GRC and residual ARC. It specifies how robust evidence/OSOs (Operational Safety Objectives) must be implemented and documented.

Residual ARC (residual air risk)

The Air Risk Class (ARC) remaining after applying strategic mitigation measures. Together with the final GRC, it determines the resulting SAIL.

ARC (Air Risk Class)

SORA indicator for air risk (collision risk with manned traffic) within the planned volume of operations. The initial ARC can be reduced through strategic and tactical measures (residual ARC).

GRC (Ground Risk Class)

SORA metric for ground risk—i.e., the risk of a person on the ground being struck by the UAS in the event of loss of control. The starting point is the "intrinsic" GRC, which can be reduced to a "final" GRC through mitigation measures.

ConOps (Concept of Operations)

Structured description of the planned UAS operation (purpose, environment, airspace, procedures, roles, technology, emergency processes). In SORA, the ConOps description forms the basis for all further risk steps.

LUC (Light UAS Operator Certificate)

Optional operator certificate in the Specific Category. Depending on the privileges granted, a LUC may allow certain operations to be approved independently (e.g., without requiring an official operating permit each time).

PDRA (Predefined Risk Assessment)

Predefined risk analysis (AMC to Art. 11 of Regulation 2019/947) for certain types of operations. The operator can apply for approval based on the PDRA without having to create a complete individual SORA from scratch—provided that all framework conditions are met.