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Modernizing communication systems is crucial for the future of aviation, and the $L$-band Digital Aeronautical Communications System (LDACS) in Air-Ground (A/G) and Air-Air (A/A) modes is being developed by European and American organizations to meet this need. In this study, we explore possible channel access schemes for aeronautical ad-hoc networks. We propose Multi-Channel Self-Organized TDMA (MCSOTDMA), a novel variant of randomized, reservation-based slotted ALOHA for LDACS A/A. In particular, we prove that it can achieve an optimal delay by following the $\frac{1}{e}$-rule of traditional slotted ALOHA's throughput. This new variant allows users to distributively converge towards an optimal channel access strategy with no a-priori knowledge of their neighborhood. It scales to any number of users and always guarantees a freely chosen, average packet collision probability. We evaluate the performance on the busiest oceanic airspace, and compare it to medium access schemes used in maritime and other aeronautical networks. We demonstrate that arbitrary collision rates can be achieved at the cost of proportional packet delay, establish communication links with deterministic performance, and implement broadcast voice messaging among pilots. We provide access to the simulator and a protocol specification under open licenses, in line with the principles of open science.

This work discusses different approaches for the cooperation between humans as a supervisor and multiple unmanned vehicles (UVs). We evaluated the most promising approach experimentally with expert pilots of the German Air Force. The co-agency of humans and highly automated unmanned systems (i.e., human autonomy teaming, HAT) is described by the use of a design and description language for HAT design patterns. This design language is used to differentiate control modes for tasking, teaming, and swarming of UVs. The different control modes are then combined in a planner agent (PA) design pattern that further enables the UV guidance on scalable delegation levels from a single individual up to a team. The desired system behavior and interaction concept of the PA for these scalable delegation levels is then transferred to the domain of manned-unmanned teaming in fighter aircraft missions. To demonstrate the applicability of the system, we implemented the concept into our fast-jet simulator of the Institute of Flight Systems (IFS) and conducted an experimental campaign with expert pilots. The results of the experiment showed (1) task delegation with the PA design pattern is faster and reduces the error potential; (2) scalable delegation levels enable a pilot and situation-specific task delegation; (3) the delegation of teams is faster and reduces the error potential; however, in some situations, deeper access through the scalable delegation levels is needed; (4) the concept is intuitive and the transparency and trust in UVs and swarms were very high; and (5) the pilots could imagine operating such systems in the future. Overall speaking the presented PA design pattern is suited for the guidance of UVs and the scalable delegation levels are beneficial.

Let Xbe a nonempty space. In the family of all topologies on Xwe can consider different kinds of relations. We examine almost semi-correspondence which is between known relations of similarity and semi-correspondence. We study this relation in the family of density-type topologies.