ABSTRACT:
Delaying aircraft on ground is one of the most used strategies when an imbalance between planned demand and actual capacity arises, either at an airport or in an airspace sector. This paper focuses on a new strategy consisting in delaying aircraft from their nominal cruise speed to the minimum fuel consumption speed. Therefore, trip times are increased and air traffic management delay can be partially performed in the air. For these flights, fuel consumption is reduced and consequently, their environmental impact. Based on data from ground delay programs at San Francisco International airport during 2006, this paper quantifies the impact that such a strategy would have had if applied to all delayed flights. Results show that for the majority of flights, the 5% to 15% of the initially assigned delay could have been absorbed in the air, leading to fuel savings in the order of 4% to 7% for each individual flight, if compared with the nominal situation.

ABSTRACT:
Air Traffic Flow Management (ATFM) regulations, such as ground holdings, are often cancelled before their initially
planned ending time. This early cancellation leads to an unnecessary ground delay and a misuse of airport or airspace resources. In previous publications, the authors have suggested a speed reduction strategy aiming at splitting the assigned ATFM delay between ground delay and airborne delay. If the aircraft flies at the minimum speed that gives the same fuel consumption as initially planned, the airline can maximise the airborne delay without any extra fuel consumption. If the regulation is cancelled before it was initially planned, the aircraft already airborne will be in a better position to recover part of the delay without incurring in additional fuel costs. In this paper, this speed reduction strategy has been simulated with the FACET tool for a whole day of flights inbound San Francisco airport (California). For each flight in the data set, it has been computed the maximum amount of airborne delay that can be performed. Moreover, the amount of delay that can be recovered has been also computed as a function of the time the regulation is cancelled. Preliminary results show, at first glance, a linear relationship between this cancellation time and the delay recovery which encourages as future work, to develop a parametric model of this delay recovery.

ABSTRACT:
This paper focuses on several aspects of the UASATM interaction that have not been previously addressed: separation assurance, contingency reaction and lost link procedures; as well as the evaluation of the trade-off between automated and autonomous UAS operations. These aspects will definitely determine the effectiveness of the UAS integration performing the aforementioned surveillance missions. Our research intents to investigate such relationships and how current ADS-B or future technology may support them. Beyond the conceptual perspective,
a simulation environment is being developed to provide functional and quantitative measures to the study of the UAS–
ATM interaction. UAS operations are modeled and reproduced in great detail through a wide set of real-time simulations. UAS behavior is being coupled with an ATC simulation environment that will allow to explore the UAS behavior to contingencies, conflicting traffic and ATC requests in real time.

ABSTRACT:
An Unmanned Aerial Vehicle (UAV) is a low-cost non-piloted airplane designed to operate in D-cube (Dangerous-Dirty-Dull) situations. Many types of UAVs exist today; however with the advent of UAV’s civil applications, the class of mini/micro UAVs is emerging as a valid option in a commercial scenario. This type of UAV shares limitations with most computer embedded systems: limited space, limited power resources, increasing computation requirements, complexity of the applications, time to market requirements, etc. These stringent requirements are highlighted in civil applications. In this case, the same platform should be able to implement a large variety of missions with little reconfiguration time and overhead if it must be economically viable.

The main thesis of this research is a middleware-based architecture specially suited to operate as a flexible payload and mission controller in a UAV. The system is composed of a number of low-cost computing devices connected by a network. The functionality of the system is divided in reusable services that can be distributed over the different nodes of the network. A middleware manages the lifecycle and the communication between services, operating the global system as a Distributed Embedded System. The communication primitives are mainly publish-subscribe based, however two-way synchronous communication, i.e remote procedure calls are also available for the services.

Additional efforts have been placed in some specifics of the UAV avionics domain, in special the interoperation with unreliable and high-latency point-to-point networks. The system not only comprises the hardware onboard the airframe, it can be extended to several UAVs and the ground control station. This problematic is managed by special nodes called Communication Gateways that act as transparent proxies for the services located away. A lot of research has been done in the area of avionics middleware; however it is mainly focused on the control domain and in the real-time operation of the middleware. Our proposal differs in that we address the implementation of easily adaptable and reconfigurable unmanned missions in low-cost and low-resources hardware. The proposed middleware architecture offers simplicity, adaptability, network transparency and a high-level vision that eases the development of this sort of missions.
 

ABSTRACT:
Nowadays, when de demand exceeds the capacity of a given sector (or airport) a ground delay programm is issued. Hence, a set of take-off slots are allocated to the affected aircraft. Based in future 4D trajectories, where a time constraint can be applied at each way-point, we propose a technique to (partially) absorb the imposed delay in the air, by flying slower than the initially planned cruize speed. We will present a cost assessment of this concept, considering fuel but also the cost of delays. This technique may be used strategically by the operators to minimize their operating costs

ABSTRACT:
The optimisation of aircraft noise abatement procedures involves several conflicting factors, including several noise  sensitive locations and aircraft operating costs. This paper presents some strategies that aim at better assessing these compromises when optimising site-specific noise abatement departure procedures that take into account the actual populated areas, their type and distribution, the hour of the day where the trajectory is supposed to be flown and the aircraft type. A special emphasis is given to the fairness of the trajectory with regards to the populated areas exposed to noise. In this context, a noise annoyance deviation index is proposed as optimisation objective. Moreover a multi-objective optimisation strategy, employing goal, lexicographic-egalitarian and hierarchical optimisation techniques is presented. An illustrative example is given with the design of the East departures at Girona airport, Catalonia (Spain). Results point out how the noise annoyance impact of current operational procedures can be significantly reduced by the optimised trajectories and show, as well, an important dependency on the type of aircraft and the hour of the day.

ABSTRACT:
Technology evolution in the field of Unmanned Aircraft Systems (UAS) will affect the Air Traffic Management (ATM) performance regarding to new military and civil applications. UAS, as new airspace users, will represent new challenges and opportunities to design the ATM system of the future. The goal of this future ATM network is to keep intact (or improve) the network in terms
of security, safety, capacity and efficiency level.

On the other hand, most UAS are, at present, designed for military purposes and very few civil applications have been developed mainly because the lack of a regulation basis concerning their certification, airworthiness and operations. Therefore, UAS operations have always been solutions highly dependent on the mission to be accomplished and on the scenario of flight. The generalized development of UAS applications is still limited by the absence of systems that support the development of the actual operations. Moreover, the systematic development of UAS missions leads to many other operational risks that need to be addressed. All this elements may delay, increase the risk and cost in the implementation of a new UAS application.

ABSTRACT:
Selecting the right autopilot to be integrated in a given UAS to develop a certain mission is a complex task because none of them are mutually compatible. Moving from one autopilot to another may imply redesign form scratch all the remaining avionics in the UAS.

This paper presents the Virtual Autopilot System (VAS), an intermediate subsystem added to the UAS platform to abstract the autopilot from the mission and payload controller in a UAS.

The VAS is a system that on one side interacts with the selected autopilot and therefore needs to be adapted to its peculiarities. On the other side, interacts with all the architecture offering standardized information of the autopilot, and consuming mission and payload orders.