Evolution of flight-rule concepts, separation management service concepts and airspace classification.  Research should cover, individually and collectively, the role of the separator and the mode of separation provision; the need for and possible updates to or renewal of the airspace classification system; the definition and potential renewal of flight rules for manned and unmanned aircraft; and a potential review/qualification of the need for visual flight rules (VFR) flights to remain in visual meteorological conditions, including the need to remain clear of cloud, given the existence of advanced electronic systems that replace and/or augment the performance of the human eye. The research must assess the impact on all current airspace users, including main airlines, business aviation, general aviation, sports aviation and military aviation, as well as considering the impact on new entrants.

• Use of advanced meteorological information and capabilities (R&I need: advanced separation management (U-space integration and new separation modes). 
• Enhanced arrival/departure runway occupancy time. The scope includes enhancing runway occupancy time calculation, through efficient runway turn-off and a combination of existing optimised braking-to-vacate solutions, at pre-selected runway exits, and new applications to assist the flight crew in achieving efficient turn-off to the point where the aircraft has left the protected area of the runway. The research should address potential on-board applications to assist the flight crew of a departing aircraft to achieve more efficient (fast, accurate, reliable and safe) line-up and take-off (R&I need: runway use optimisation through integrated use of arrival and departure TBS tools);
• Optimised and resilient runway throughput. This element investigates how to enhance MET resilience in low-visibility conditions and during thunderstorms, and considers the need for parallel or near-parallel instrument runway separations in the light of advanced technology and surveillance capabilities integrated with coupled AMAN / departure management (DMAN) and TBS toolkits for both arrivals and departures (R&I need: runway use optimisation through integrated use of arrival and departure TBS tools).
• Adaptation of ground and airborne safety nets to new separation modes. This element covers advanced separation management that will require close conformance monitoring of the negotiated and authorised flight trajectories throughout the execution phase, so that operations are not disturbed by unnecessary resolution advisories, in particular if lower separation minima are introduced/considered.
• TBO machine-to-machine flight deck to ATC negotiation. This element covers machine-to-machine negotiation-based conflict resolution. The development of mechanisms and tools for creating negotiation-based resolutions at conflict resolution and collision avoidance levels (e.g. what-if extended projected profile (EPP)-based tools, or ATC offering a choice to the FMS of two potential cruising levels) will be addressed.
• Space-based multilateration. This element covers space-based multilateration through ranging by satellites already used for space-based VHF or ADS-B systems, with preference given to those used for space-based ADS-B, as this could serve to cross-check the GNSS position acquired through ADS-B (in the same way that Mode S radar has a double check).
• Arbitrary levels. This research is aimed at enabling aircraft to fly at any arbitrary flight level, as optimised by aircraft performance, weight and atmospheric conditions. Even/odd cruise level assignment should be based on traffic supply, rather than on the semi-circular rule (also known as the hemispheric rule).
• Additional extended AMAN capabilities. The scope includes investigating AMAN capabilities, focusing on the transfer of the predicted arrival holding times from the TMA to the upstream airspace to reduce holding, the use of ML for the refinement of AMAN algorithms, etc. (R&I need: intelligent queue management).
• Enhanced departure queue management. This element covers enhancing departure queue management through further automation and exchange of highly accurate trajectory information between all actors (i.e. airports, ANSPs and aircraft operators).
• Data-sharing between airport collaborative decision-making (A-CDM) parties, arrival and departure managers, and TBS tools. This element focuses on data-sharing between A-CDM parties, arrival and departure managers, and TBS tools, to allow the dynamic optimisation of runway use based on prevailing operational needs (R&I need: runway use optimisation through integrated use of arrival and departure TBS tools).
• Digital coupled AMAN–DMAN function. This element is about enhancing coupled AMAN–DMAN functions using ML and AI techniques identify the most appropriate departing aircraft to make use of an arrival gap. This information is to be shared with airport systems to ensure that the departing aircraft is loaded in a timely manner and taxies to the right place at the right time to be ready to take off (R&I need: runway use optimisation through integrated use of arrival and departure TBS tools).
• Improved visual separation procedures for the aerodrome circuit. This element is about reviewing current minimum separation standards/procedures in the airport environment, to meet a minimum acceptable safety level (i.e. moving away from pre-determined separation standards). The research should look at improved visual separation procedures for the aerodrome circuit, for example using a combination of surveillance and system support, targeting busy airports with high VFR traffic, in particular those that need to integrate IFR and VFR traffic (e.g. Charleroi airport).
• Application of physiological measurements to ATCOs. The aim is to research the application of physiological measurements to ATCOs (e.g. measuring brain waves to assess the level of attention, using speech recognition combined with physiological measurements to monitor stress, correlation of eye-movement patterns with the occurrence of events that are potentially safety relevant).
• Trajectory broker in all phases of ATFM operation. This element covers the trajectory broker layer, including research on how to make better use of available capacity in all phases of ATFM operation (long-term, medium-term, short-term and execution phases) and in all areas (airport, TMA, en route), addressing technical aspects but also considering the necessary regulatory/organisational changes.