Introduction to Development of a Time-Space Diagram to Assist ATC in Monitoring
Continuous Descent Approaches Continuous Descent Approaches (CDA) have shown to result in considerable reductions of aircraft noise during the approach phase of the flight (Erkelens, 2002). Due to uncertainties in aircraft behaviour, Air Traffic Control (ATC) tends to increase the minimum spacing interval in these approaches, leading to considerable reductions of runway capacity (Clarke, 2000). To enable the application of such procedures in higher traffic volumes, research has advanced in the creation of airborne tools and 4-dimensional prediction algorithms. Little research has addressed the problem of sequencing and merging aircraft in such an ap- proach, however. In this chapter we present the Time-Space Diagram (TSD) display that shows the aircraft along-track distance to the runway versus the time. On this display, the in-trail separation is presented as the horizontal distance between two predictions. It is hy- pothesised that this display will enable the air traffic controller to meter, sequence and merge aircraft flying a CDA at higher traffic volumes. In this chapter, the TSD will be introduced and the effects of various common separation techniques on the predictions of the display are discussed in detail. The display is currently being evaluated by actual air traffic controllers in a simulated traffic scenario to provide an initial validation of the design. Problem statement ATC in CDA procedures According to Annex 11 to the Convention on Civil Aviation (ICAO, 2003), the primary goal of ATC is to provide service for the purpose of safe, orderly and expeditious flow of traffic. In approach control, this task can be described as minimising delays while maintaining suf- ficient separation between the aircraft. During the TDDA, the in-trail distance between two approaching aircraft should therefore reach, but not go below, the minimal distance required. To achieve this, the primary tool common to all approach controllers is the two-dimensional Plan View Display (PVD). This screen shows the, mostly radar-derived, planar positions of the aircraft combined with numeric data on their velocity and altitude. Using this data, the Air Traffic Controller (ATCo) builds a mental model of the traffic scenario, commonly referred to as the “picture” (Nunes & Mogford, 2003). By mentally predicting the trajectories of the aircraft on the screen, the controllers can anticipate on the future spacing and select the ap- propriate actions to adjust spacing if necessary. The certainty of predicting the aircraft future positions depends on the skill of the controller, the behaviour of the aircraft involved and the length of the interval over which the prediction is made (Reynolds et al., 2005). Controller prediction accuracy…
Introduction to Investigating requirements for the design of a 3D weather visualization environment for air traffic controllers
This chapter involves a long-term investigation into the applicability of three-dimensional (3D) interfaces for Air Traffic Control Officers (ATCOs). This investigation is part of collaboration between EUROCONTROL Experimental Centre (EEC) and the Norrköping Visualization and Interaction Studio (NVIS) of Linköping University in which a test-bed was developed in order to evaluate the different features of a 3D interface for ATCOs. This test- bed, known as the 3D-Air Traffic Control (3D-ATC) application, provides controllers with a detailed semi-immersive stereoscopic 3D representation of air traffic. Different aspects of the 3D-ATC application include 3D visualization and interactive resolution of potential conflict between flights (Lange et al., 2006), a voice command interface for visualizing air traffic (Lange et al., 2003), and interactive 3D weather images (Bourgois et al., 2005). Among these various features, the 3D weather visualization was chosen as a first case for carrying out a more accurate users’ study. Weather is considered as one of the major factors contributing to aviation accidents (Spirkovska and Lodha, 2002). As stated by Kauffmann and Pothanun (2000) “weather related accidents comprise 33% of commercial carrier accidents and 27% of General Aviation (GA) accidents”. Moreover, adequate weather information (both for now-cast and forecast information) is often not available to pilots or controllers. The limitation in the way the weather information is represented in current weather displays has been also pointed out in…
Introduction to Time-based Spaced Continuous Descent
Approaches in busy Terminal Manoeuvring Areas Mitigation of aircraft noise for approaching aircraft is an area where considerable improve- ments are still possible through the introduction of noise abatement procedures, such as the Continuous Descent Approach (CDA) (Erkelens, 2000). One of the main issues when imple- menting CDAs is their negative effect on runway throughput, especially during busy oper- ations in daytime. A reduction in landing time intervals might be achieved through precise inter arrival spacing. The combination of aircraft performing the CDA controlled by precise spacing algorithms is seen as one of the solutions to safely increase runway throughput, re- duce delay times for arriving aircraft, and reducing fuel burn, emissions and noise impact (De Gaay Fortman et al., 2007; De Leege et al., 2009; De Prins et al., 2007). The main algorithms used in these researches are all based on the Flap/Gear Scheduler (FGS) developed by Koeslag (2001) and improved by In ‘t Veld et al. (2009). The FGS is evaluated in these researches to investigate the effects of different flight path angles, different types of aircraft, different aircraft weight configurations and different wind conditions on FGS perfor- mance. The FGS is also combined with time and distance based spacing algorithms to ensure proper spacing between aircraft in arrival streams. There are more spacing algorithms developed to control the Time-based Spaced CDA (TSCDA), such as the Thrust Controller (TC) by De Muynck et al. (2008) and the Speed Constraint De- viation controller (SCD), both developed at the National Aerospace Laboratory (NLR). The performances of these three controllers are evaluated in this chapter. Fast-time Monte Carlo Simulations (MCS) are performed using a realistic simulation environment and a realistic sce- nario. The effects of different wind conditions, aircraft weight configuration, arrival stream setup and the position of the aircraft in the arrival stream on the performance of the controllers are also evaluated. In Section 2 the definition of the TSCDA is elaborated by discussing the goals of this concept and by giving the description of the approach used in this research. In Section 3 the working principles of the controllers are discussed. The results of the initial simulations performed to…
Introduction to The potential of some of the innovative operational procedures for increasing the airport landing capacity
Despite continuous efforts by the air transport system operators, regulators, and researchers (academic and consultants), the problem of providing sufficient airport runway capacity to match continuously growing demand safely, efficiently, and effectively has had rather limited success. A[art from growing demand, the specific environmental (mainly noise) constraints at many large airports both in US and Europe have prevented the full utilization of the designed runway capacity. The sharp concentration of atms (air transport movements) (one atm corresponds to one landing or one take off) within the rather short time periods at the hub airports due to operating the hub-and-spoke networks has created sharp peaks causing further already existing imbalance between demand and the available runway capacity. At some other airports one of which is, for example New York La Guardia airport (US), a high demand/capacity imbalance has been created simply because of their attractiveness and not primarily due the type of airline scheduling practice. In addition, specifically in the US, the operation of airports under IMC (Instrument Meteorological Conditions) and VMC (Visual Meteorological Conditions) and the corresponding difference in the ATC (Air Traffic Control) minimum landing distance-based separation rules (IFR – Instrument Flight Rules, and VFR – Visual Flight Rules, respectively) have inherently created instability of the airports’ declared runway landing capacities and consequently their rather high vulnerability to weather conditions. In Europe, such capacity instability caused by weather has also been relatively high, even though the aircraft landings have been carried out exclusively by applying IFR under both IMC and VMC. As well, the shortage of land for expanding the airport runway capacity at many airports has also contributed to the above-mentioned demand/capacity imbalance there…
Introduction to Link Capacity Dimensioning
Model of ATS Ground Voice Network Apart from a number of new technologies which are currently implemented in air traffic control for the exchange of messages the ground/ground (G/G) voice communication is still very significant and is currently irreplaceable. The problem regarding introduction of new technologies that would replace voice communication lies in insufficient development and linking of very expensive ATM (Air Traffic Management) systems that have been already in implementation for a number of years. The best indicator showing this is the implementation of MFC (Multi Frequency Coding) standard which is still being implemented in the majority of Eurocontrol member countries. The introduction of advanced automatic message exchange system in ATM will result in the reduction of voice communication in coordination. It will not be possible, however, to perform the implementation of the new systems that will enable exchange of data essential for the coordination, integrally for all the ATM users, so that voice communication will continue to be implemented either as a basic service or as a backup service. In order to realize the planning and dimensioning of the telecommunication network for G/G voice communication which is to be the basic task of this paper, it is necessary to have all the data on the relevant network parameters that may affect the very operation…
Introduction to Stability of switched stochastic nonlinear systems
Hybrid systems are digital real-time systems which are embedded in analog environment. Analog part of the hybrid system is described with differential equations and discrete part of the hybrid systems is an event driven dynamics which can be described using concept from discrete event systems (Cassandras & Lafortune, 2008) and (Tabuada, 2009). In this paper we will consider the switched systems which can be viewed as higher-level abstraction of hybrid systems (Liberzon, 2003) and (Sun & Ge, 2005).We model each subsystem of a switched system by differential equation. There are two ways for analysis of stability of switched deterministic systems. The first one is a construction of common Lyapunov function. Find the common Lyapunov functions is a difficult task (Narendra & Balakrishnan, 1994). The second one utilizes multiple Lyapunov functions for analysis of switched systems (Branicky, 1998). In this paper we will consider a stability of switched stochastic systems. We assume that (i) there is no jump in the state at switching instants and (ii) there is no Zeno behaviour, i.e. there is finite number of switches on every bounded interval of time. The situation with jump in the state of x at the switching instants is considered in (Guan et. al., 2005) and (Li et al., 2005). In recent years the stochastic hybrid systems become hot research topic. There are a few approaches to the problem. In the stochastic setting we have jump diffusion as the solution of stochastic differential equation driven by Levy process which is a linear combination of time, Brownian motion and pure jump process (Oksendal & Sulem, 2005). Close to deterministic hybrid systems is the concept of Piecewise deterministic …
Introduction to Dynamic Airspace Management
Models and Algorithms Global air transport has been growing for decades and is expected to continue increasing in the future. The development of the air transport system has significantly increased the demands on airspace system resources. During the past several years, the operational concept of Dynamic Airspace Management has been developed to balance the mushrooming demands and limited airspace resources. The Dynamic Airspace Management is an important approach to extend limited airspace re- sources by using them more efficiently and more flexibly. Under the Dynamic Airspace Man- agement paradigm, the national airspace is administrated as a unified resource with tempo- rary utilization clearances assigned to various airspace users on demand and reclaimed at the end of the utilization period. The structure of airspace can be changed as well if needed. The airspace system typically has civil users and military users. In China, for example, most of the airspace is administrated by the military except for a few air routes reserved for civil avi- ation, that resemble a lot of tubes through the airspace. The air transport system is restricted not only by insufficient airport capacities (as in the United States) and sector capacities (as in Europe), but also by the structure and the management policy of air route networks. When there is a temporary increase of the air traffic demands or a decrease of airspace capacities, the civil air traffic controllers usually have to apply for additional routes from the military. In the last two decades, the models and algorithms for Air Traffic Flow Management (ATFM) have been …
Engine Room Bottom Platform Explored
We have been reading a lot about the engine room of the ship and layout of components on various platform. We have also learnt about the engine control room. In this article we will take…
Diagnosing Causes of High EGT in Marine Engines
There are several common reasons for high exhaust temperatures in marine diesel engines, but MOST causes can be attributed to a scavenge fire and/or a defective fuel valve, both of…
