Air transportation is essential for society, and it is increasing gradually due to its importance. To improve the airspace operation, new technologies are under development, such as Unmanned Aircraft Systems (UAS). In fact, in the past few years, there has been a growth in UAS numbers in segregated airspace. However, there is an interest in integrating these aircraft into the National Airspace System (NAS). The UAS is vital to different industries due to its advantages brought to the airspace (e.g., efficiency). Conversely, the relationship between UAS and Air Traffic Control (ATC) needs to be well-defined due to the impacts on ATC capacity these aircraft may present. Throughout the years, this impact may be lower than it is nowadays because the current lack of familiarity in this relationship contributes to higher workload levels. Thereupon, the primary goal of this research is to present a comprehensive review of the advancements in the integration of UAS in the National Airspace System (NAS) from different perspectives. We consider the challenges regarding simulation, final approach, and optimization of problems related to the interoperability of such systems in the airspace. Finally, we identify several open challenges in the field based on the existing state-of-the-art proposals.

In the Looney Tunes show, the Roadrunner character is infamous for his speedy escapes from his arch nemesis, Wild. Now, a team of drone experts who named themselves after the fast-running cartoon character have lived up to the name, setting a new record for long-distance drone delivery. Team Roadrunner managed to fly a fixed-wing drone 97 miles (156km) over Texas this week, using cellular connectivity. Team Roadrunner used a combination of a mobile command and control, a visual observer team and stationary visual observers equipped with radios to fly the UAV. The drone launched from a central Texas location, and flew a pre-planned route through the National Airspace System. It landed and delivered its four pound (1.8 kilogram) package in Austin.