Abbreviation for Advanced Air Mobility – a collective term for new, mostly highly digitized air transport concepts (manned and unmanned aircraft), e.g., eVTOL air taxis and automated cargo drones, including the necessary infrastructure and operating procedures.

A U‑Space service is a service provided in designated U‑Space airspace to support safe and efficient UAS operations. The EU regulation specifies mandatory U‑Space services such as network identification, geo‑awareness, traffic information, and UAS flight authorization, which are offered by certified U‑Space service providers (USSPs).

SORA 2.5 (Specific Operations Risk Assessment) is the risk-based methodology developed by JARUS for assessing and deriving safety requirements for UAS operations in the "specific" category. EASA has integrated SORA 2.5 into AMC/GM to VO (EU) 2019/947 (ED Decision 2025/018/R).

"HX" indicates airspace that is temporarily effective (not permanently active). Before entering, the status should be checked, e.g., via FIS/INFO/TWR/ATIS; without checking the status, the airspace should be treated as active, and standby listening is also required.

Airspace class G: Uncontrolled airspace according to SERA; IFR and VFR are generally permitted, there is no ATC control service and no separation; flights receive flight information service (FIS) where possible or on request. For IFR outside controlled airspace, the requirements of SERA.5025 apply (e.g., radio communication is only mandatory in areas/routes specified by the authorities). In Germany, airspace G generally extends from the ground to 2,500 ft AGL, unless interrupted by other airspaces; IFR in airspace G is generally not permitted nationally and is only permitted in strictly defined, published procedures/routes.

Airspace Class F (Advisory Airspace): IFR and VFR are permitted; participating IFR flights receive an Air Traffic Advisory Service, all flights can receive Flight Information Service (FIS); ATC clearance is not required (radio communication mandatory for participating IFR).

Airspace Class E: IFR and VFR are permitted; ATC service and separation only for IFR (IFR separated from IFR). VFR does not normally receive ATC service, traffic information "as far as practical"; IFR requires clearance and radio communication, VFR not mandatory.

Airspace Class D: IFR and VFR are permitted; ATC service for all. IFR is separated from IFR and receives traffic information on VFR; VFR receives traffic information on all flights; clearance and radio communication are required.

Airspace Class C: IFR and VFR are permitted; ATC service for all. IFR is separated from IFR and VFR; VFR is separated from IFR and receives traffic information (and, upon request, avoidance advice); clearance and radio communication are required.

Airspace Class B: IFR and VFR are permitted; all flights receive ATC service, are separated from each other, and require clearance; continuous radio communication is required.