National Airspace System

Since the STS-114 mission in August of 2005, the FAA has partnered with NASA to protect aircraft flying in the National Airspace System from the potential hazards associated with a catastrophic failure of a reentering Space Shuttle orbiter, similar to that which occurred during ...

Driven by anticipated increase in satellite deployments and corresponding increase on spacelaunch demand, numerous domestic and international government programs as well as several "start-up" private ventures have been formed to develop launch vehicles that will provide less expensive alternatives to the current fleet, including numerous reusable launch vehicle concepts. The different launch-vehicle concepts are expected to have different operational characteristics, and thus different impact and requirements on the National Airspace System (NAS). This paper describes a set of computer analysis capabilities being developed for the study of air traffic management issues related to the space operations. NASA already has the Future ATM Concepts Evaluation Tool (FACET) for evaluation of advanced technologies on the air traffic over the continental U.S. The computer tool described in this paper builds on FACET to include the capability to model and analyze space-flight operations within the NAS. Specifically, it includes an extensible model database for inclusion of future launch and return vehicle models for simulation and analysis; modeling of new reserved airspace definitions; functionality for analyzing launch/return operations and potential debris fallout; and more powerful visualization capabilities. The computer tool will be instrumental for studying the interaction of air and space traffic with regard to such issues as air traffic control, spaceport operations, airspace environments, automation and decision-support tools, and communication, navigation, and surveillance.

This paper describes a methodology to integrate air transportation demand estimates in the preliminary aircraft design process. The paper describes the adaptation of the Transportation Systems Analysis Model (TSAM) developed by the Air Transportation Systems Laboratory at Virginia Tech for NASA Langley Research Center to predict potential demand of aerospace vehicle concepts. TSAM uses traditional air transportation systems engineering techniques to: 1) predict the number of intercity trips generated in the country based on socio-economic factors, 2) distribute these trips across the country, 3) predict the most likely modes of transportation used to execute these trips, 4) predict flights and trajectories associated with air transportation trips, and 5) predict impacts of the intercity trips generated in the National Airspace System (NAS). The paper includes a case study to estimate the potential demand for advanced tilt-rotor aircraft technology operating in the Northeast Corridor in the United States.

Ο όρος «εναέριος χώρος» χρησιμοποιείται σε αντιδιαστολή και συμπληρωματικά προς τα καθεστώτα κυριαρχίας που έχει ένα κράτος επί των χερσαίων εκτάσεών του, καθώς και της κυριαρχίας ή των κυριαρχικών δικαιωμάτων που έχει σε θαλάσσιους χώρους όπως αυτοί εθιμικά ή τυπικά ορίζονται από το ίδιο ή διεθνείς συμβάσεις, όπως αυτή για το Δίκαιο της Θάλασσας (1982). Στον εναέριο χώρο ισχύουν επάλληλα ή μεμονωμένα τρία διαφορετικά καθεστώτα: α) το καθεστώς του εθνικού εναερίου χώρου, μέσα στον οποίο το κράτος ασκεί κυριαρχία, όπως στο έδαφος του και στην αιγιαλίτιδα, β) το καθεστώς της Περιοχής Πληροφόρησης Πτήσεων (Flight Information Region, FIR), όπου η Ελλάδα και η εκάστοτε χώρα ασκεί συγκεκριμένες διεθνείς αρμοδιότητες εποπτείας και ελέγχου, και γ) το καθεστώς επιχειρησιακού ελέγχου στο Αιγαίο, με βάση το οποίο η Ελλάδα ασκεί ρυθμιστικές αρμοδιότητες στα πλαίσια του ΝΑΤΟ, οι οποίες αμφισβητήθηκαν από την Τουρκία μετά την αποχώρηση της Ελλάδας από το στρατιωτικό σκέλος της Συμμαχίας το 1974. Στο παρόν άρθρο θα εξετάσουμε ποια από αυτά τα καθεστώτα αμφισβητεί τυπικά ή έμπρακτα η Τουρκία και με ποιο τρόπο επιχειρεί να τα μεταβάλλει ή αντικαταστήσει.

The common belief that safety in aviation is created through global and regional international aviation organizations is true, however it does not fully convey the core of the problem. The standards and directives shaping the safety system in aviation are important, however these are merely strategic tools for shaping the policy and safety strategies in aviation. The real activity in this area is performed at the very bottom of the aviation structure, directly in an air company, particularly in an airline, that is, by a carrier who provides carriage and cargo services. The reason for initiating research in this area was an attempt to find answers to the following questions: to what extent does safety policy pursued by air companies influence the image of those companies as well as the assessment and safety feeling on the part of the passengers? Is investment in safety profitable from the standpoint of an airline? The above-mentioned problems, presented in a form of a report of the conducted research, constitute the bulk of this article. It should be noted that the fragmentary research undertaken in the course of work over the subject of safety conditioning in airlines may form the basis to plan further research in this area.
KEY WORDS Safety in aviation, safety threat in aviation, emergencies .

ÖZET Halk hareketlerinin başladığı 2011'den bu yana devam eden kaos ortamı, Suriye'yi yoğun bir güç mücadelesi sahasına dönüştürmüştür. Bölge gerek Suriye'deki yerel aktörlerin, gerekse ulusal çıkarlarını maksimize etmeye çalışan bölgesel ve küresel güçlerin mücadele arenası halini almıştır. Çatışmaların artan şiddeti sonucu kitlesel göç dalgaları Türkiye'ye yönelmiş, terörist eylem ve faaliyetler Türkiye'yi de tehdit eder duruma gelmiştir. Suriye ile yaklaşık 900 km'lik kara sınırına sahip olan Türkiye, kendi güvenliğini sağlamak maksadıyla hudut hattındaki savunma tedbirlerini artırmak ve angajman kurallarını değiştirmek durumunda kalmıştır. Alınan tedbirlere rağmen rejim ve terörist örgütler tarafından askerî unsur ve ülke topraklarına yönelik fiili saldırıların meydana gelmesi, Türkiye'yi uluslararası hukukun kendisine verdiği yetki çerçevesinde karşılık vermeye yöneltmiştir. Bu olaylardan birisi de Türk hava sahasını ihlal eden bir Rus SU-24 uçağının düşürülmesi olayıdır. Bu çalışmanın amacı da çoğunlukla askerî, ekonomik ve Türk-Rus ikili ilişkileri ekseninde tartışılan, Türkiye'nin güvenlik politikasına ilişkin bu olayın, uluslararası antlaşmalar ve hukuk boyutuyla ele alınarak incelenmesidir. Bu maksatla konuya ilişkin ikili ve/veya uluslararası antlaşmalar, konvansiyonlar ve Türkiye'nin kendi iç hukuk mevzuatı, eleştirel literatür incelemesi yöntemiyle taranmış ve doğrudan ilişkili bulunan dokümanlar üzerinden betimsel bir yöntemle olay değerlendirilmiştir. Sonuç olarak, Rus uçağına yapılan müdahalenin uluslararası ve ulusal mevzuat çerçevesinde meşru olduğu değerlendirilmiştir. Anahtar Kelimeler: Güvenlik Politikası, Kamu Politikası, Hava Sahası İhlali, Meşru Müdafaa, Angajman Kuralları.

UAVs are part of common lexicon and very soon would be part of daily life. Till the very recent past, they flew in segregated airspace under the control of the military and for military tasks. As they proliferate in the 'civilian' domain, this essay looks at the immense challenges in integrating them in national airspace for unhindered everyday operations, like commercial aviation. As UCAVs mature in the coming years, integrating them would be an even bigger issue.

There are 3,091 counties in TSAM serving as the zones of travel activity in the continental United States. The trip-generation output is made up of two 3091 vectors: one for attractions and the other for productions for each county. Trip distribution fills up the cells between the vectors, creating a person-trip interchange table of demand between the two counties. Mode choice splits the demand between each county by mode of transportation. The mode choice model in TSAM and this paper estimates both the demand by mode between counties and the demand flows in the airport network associated with the counties. This is achieved by embedding an airport choice model in the mode choice model. Hence the model is both a mode choice and a partial trip assignment model. The framework for the process is shown in . The modes of transportation considered in the TSAM model are commercial airline, automobile, SATS, and train. However, the focus in this paper is on the baseline model, which has only automobile and commercial airline modes. The trip assignment in TSAM involves converting the airport-to-airport person trips into aircraft operations, generating flights by using a time-of-day profile, and loading the flights on the National Airspace System to estimate the impact of aircraft operations in the system. The complete travel demand model is fully documented elsewhere (1-3).

This paper relates to the evaluation of Retro-Rotary Flywheel Propulsion (RFP) when applied to Air breathing Hybrid Eolic Propulsion (AHEP) systems for aerodynamic flight, and of space-borne direct/dynamic RTR main systems applied to electric-power co-generation systems for outer space travel, through the basic design concept of the US National Space Plane (NASP), also known as X-30.

Hava sahasının uygun şekilde takip, kontrol ve yönetimi uçuş emniyeti ve hava trafiğinin kesintisiz olarak sürmesi için bir zorunluluktur. Günümüzde hızla gelişen havacılık sektörünün aynı hızla gelişmesi durumunda çok yakın gelecekte uygun takip, kontrol ve yönetim sistemlerinin kullanılmaması durumunda uçuş emniyeti olumsuz yönde etkilenecek ve hava taşımacılığı sekteye uğrayacaktır.
Her gün milyonlarca hava aracının gökyüzüne doğru havalanması milyonlarca yolcunun varmak istedikleri yere emniyetli, süratli ve rahat bir şekilde ulaşmak için hava yollarını tercih ettiği anlamına gelmektedir. Hava sahasının takip, kontrol ve yönetiminden sorumlu hava trafik kontrolörlerinin görevi de milyonlarca hava aracının birbirlerine çarpmadan, emniyetli ve en süratli şekilde hedeflerine varmalarını sağlamaktır.
Hava sahası kontrol, takip ve yönetim sistemi aşağıda belirtilen alanları kapsayan bir sistemler bütünüdür, bu bütünlük içerisinde koordinasyon sağlıklı bir sistemin tesis ve idamesi için çok önemlidir. Hava sahasının takip, kontrol ve yönetiminde birbirine entegre olmuş system yaklaşımı esas alınmalı, bileşenlerden herhangi birinin eksik yapılmasının bütün sistemin güvenlik ve etkinliğini olumsuz yönde etkileyeceği unutulmamalıdır.

We present requirements for Super Dense Operations (SDO) in a future Next Generation Air Transportation System (NGATS), targeted at a 2025 timeframe. The requirements emphasize the needs for dynamic weather avoidance maneuvering and Performance-Based Services (PBS) based on Required Navigation Performance (RNP). A Net-Centric Operation (NCO) will provide a mechanism to inform all users of weather forecast information, hazardous weather constraints, and weather avoidance routing requirements. The future Air Traffic Management (ATM) system will move away from static jet route navigation toward a system where routes are defined more dynamically, adjusted during the course of the day as required by traffic demand and the geometry of severe weather constraints. Such a Concept of Operation (ConOps) will be particularly useful for time periods where weather is a major terminal area constraint in the National Airspace System (NAS), making it possible to achieve SDO, reduce traffic delays, and ensure safe operations that would otherwise not be feasible in current day operations. • ATSP-Air Traffic Service Provider • FD-Flight Deck to share information and maintain a common situation awareness of the NAS and its relevant SDO constraints. An NCO system provides a robust, secure, common representation of the ATM state variables and access to data to provide the best shared situational awareness possible between FOCs, FDs, and ATSP, by integrating and distributing sensor, trajectory, command and control, performance, and communications data. SWIM performs the tasks of data collection, data fusion, data cleansing, data security (protecting proprietary and National security information), and timely data distribution through a common messaging protocol. An NCO system is designed to push and pull (publish and subscribe) data (e.g., flight plan objects, 4D trajectories (4DTs), weather data, and NAS status information) utilizing common representations that make collaboration and coordination among disparate types of users and applications possible. SWIM, including standards and protocols, is the first step toward the NAS NCO system providing ground-ground connectivity. The NGATS will include links between aircraft and essential ground services to provide air-ground and air-air connectivity that will facilitate SDO. As a part of SWIM, current and forecasted weather information for the entire NAS will be collected from various sources such as satellite, airbased electronic flight reporting systems (E-PIREPS), the Meteorological Data Collection and Reporting System (MDCRS), Tropospheric Airborne Meteorological Data Reporting (TAMDAR), ground-based Integrated Terminal Weather System (ITWS), Corridor Integrated Weather System (CIWS), etc. Data will be fused, distributed to all ATSP facilities, and made available to all users in the NAS via SWIM to support SDO. SWIM will facilitate and possibly automate queries on this fused database of weather (as well as other) information. The NGATS will exploit this fused weather information in SDO,

To support the need for increased flexibility and capacity in the future National Airspace System, NASA is pursuing an approach that distributes air traffic separation and management tasks to both airborne and ground-based systems. Details of the distributed operations and the benefits and technical challenges of such a system are discussed. Technology requirements and research issues are outlined, and NASA's approach for establishing concept feasibility, which includes development of the airborne automation necessary to support the concept, is described.

Author: Abkin, Michael H., ATAC Gilgur, Alexander, ATAC Bobick, John C., ATAC Hansman, R. John, MIT Reynolds, Tom G., MIT Vigeant-Langlois, Laurence, MIT Hansen, Mark, UCB Gosling, Geoffrey D., UCB Baumgardner, William F., UCB ... Publication Info: Research ...

The National Airspace System (NAS) is a large and complex system with thousands of interrelated components: administration, control centers, airports, airlines, aircraft, passengers, etc. The complexity of the NAS creates many difficulties in management and control. One of the most pressing problems is flight delay. Delay creates high cost to airlines, complaints from passengers, and difficulties for airport operations. As demand on the system increases, the delay problem becomes more and more prominent. For this reason, it is essential for the Federal Aviation Administration to understand the causes of delay and to find ways to reduce delay. Major contributing factors to delay are congestion at the origin airport, weather, increasing demand, and air traffic management (ATM) decisions such as the Ground Delay Programs (GDP). Delay is an inherently stochastic phenomenon. Even if all known causal factors could be accounted for, macro-level national airspace system (NAS) delays could not be predicted with certainty from micro-level aircraft information. This paper presents a stochastic model that uses Bayesian Networks (BNs) to model the relationships among different components of aircraft delay and the causal factors that affect delays. A case study on delays of departure flights from Chicago O'Hare international airport (ORD) to Hartsfield-Jackson Atlanta International Airport (ATL) reveals how local and system level environmental and human-caused factors combine to affect components of delay, and how these components contribute to the final arrival delay at the destination airport.

NASA and the Federal Aviation Administration (FAA) have designed and developed an automation tool known as the Traffic Management Advisor (TMA). The TMA is a time-based strategic planning tool that provides Traffic Management Coordinators (TMCs) and En Route Air Traffic Controllers the ability to efficiently optimize the capacity of a demand-impacted airport. The TMA consists of trajectory prediction, constraint-based runway scheduling, traffic flow visualization and controller advisories. The TMA was used and operationally evaluated for thirty-nine rush traffic periods during a one month period in the Summer of 1996 at the Fort Worth Air Route Traffic Control Center (ARTCC). The evaluations included all shifts of air traffic operations as well as periods of inclement weather. Performance data were collected for engineering and human factor analysis and compared with similar operations without the TMA. The engineering data indicate that the operations with the TMA show a one to two minute per aircraft delay reduction during rush periods. The human factor data indicate a perceived reduction in en route controller workload as well as an increase in job satisfaction. Upon completion of the evaluation, the TMA has continued to be a primary traffic management tool of daily operations at the Fort Worth ARTCC.

NASA and the Federal Aviation Administration (FAA) have designed and developed an automation tool known as the Traffic Management Advisor (TMA). The TMA is a time-based strategic planning tool that provides Traffic Management Coordinators (TMCs) and En Route Air Traffic Controllers the ability to efficiently optimize the capacity of a demand-impacted airport. The TMA consists of trajectory prediction, constraint-based runway scheduling, traffic flow visualization and controller advisories. The TMA was used and operationally evaluated for thirty-nine rush traffic periods during a one month period in the Summer of 1996 at the Fort Worth Air Route Traffic Control Center (ARTCC). The evaluations included all shifts of air traffic operations as well as periods of inclement weather. Performance data were collected for engineering and human factor analysis and compared with similar operations without the TMA. The engineering data indicate that the operations with the TMA show a one to two minute per aircraft delay reduction during rush periods. The human factor data indicate a perceived reduction in en route controller workload as well as an increase in job satisfaction. Upon completion of the evaluation, the TMA has continued to be a primary traffic management tool of daily operations at the Fort Worth ARTCC.

This paper presents a concept for improving National Airspace System (NAS) operations through the adoption of a flexible combination of time-based traffic flow management, trajectoryorientation, and airborne separation assistance elements. Time-based traffic flow management on a NAS-wide and local level assures that local airspace areas are not overloaded at any given time. Trajectory-based operations are used to plan and execute conflict free flight paths for upcoming flight segments. Together, these operations put flight crews in a position to utilize Airborne Separation Assistance Systems (ASAS) to deal with local separation issues, if instructed or permitted by the controller to do so.

Many service enterprise systems such as the airport departure systems are typical multistage multi- variable systems with non-linear complex interactions between stages. These systems function over a wide range of operating conditions and are subject to random disturbances, which further enhance the non-linear characteristics. Also, there are many uncertain factors which often makes it is dicult to describe the process

This paper presents an aided dead reckoning navigation system based on the fusion of inexpensive inertial, air data and magnetic sensors aided by a skeletal network of radio-navigation aids. In the future National Airspace System of the United States–in which GPS is slated to be the primary means of navigation alongside a very small skeletal network of existing ground based radio-navigation aids–an inexpensive backup method of navigation will be required for General Aviation users. This backup method of navigation will allow users to successfully deal with scenarios where intentional or unintentional radio-magnetic interference renders GPS unusable in a given geographic area. The navigator presented in this paper is intended to be that backup navigation system for General Aviation aircraft. Dead reckoning navigators mechanized using the classical inertial navigation techniques have traditionally been the solution to providing an alternate means of navigation that is mostly self-cont...

Trajectory-Based Operations is a NextGen initiative that seeks to increase the effective-capacity of the National Airspace System by adding flexibility to the 4-D trajectories as flights traverse airspace. More flexible trajectories can minimize the airlines operating costs (i.e., distance flown), shift the geography of Air Traffic Control (ATC) workload (i.e., sectors used), shift the time-intensity of ATC workload (i.e., flights counts per sector), and reduce congestion in the destination airports.

Many service enterprise systems such as the airport departure systems are typical multistage multi- variable systems with non-linear complex interactions between stages. These systems function over a wide range of operating conditions and are subject to random disturbances, which further enhance the non-linear characteristics. Also, there are many uncertain factors which often makes it is dicult to describe the process

Making greater use of smaller airports is one way that has been proposed to increase the capacity of the National Airspace System. A major difficulty is that many small airports do not have control towers, and thus capacity is severely limited during poor visibility. We consider a proposed system in which airplanes self-separate, so they are able to land at higher capacities without a control tower. Before such a system is implemented, it must first be shown to be safe. Safety is a difficult metric to measure and predict, because accidents are so rare. Even computer simulation can be slow because of the long time to observe accidents. One methodology that has been successful in assessing aviation safety through simulation is TOPAZ (Traffic Organizer and Perturbation AnalyZer). In this paper, we apply the methodology to assess the safety of the proposed non-towered system. In particular, we estimate the probability of collisions on the runway in poor visibility.

A comprehensive look at the different aspects of Beijing's ADIZ in the East-China Sea, including the motivations behind the move, the reaction by different countries (including Taiwan and Russia), the origins and evolution of ADIZs in international law, and the underlying conflicts between China and other nations. The paper also provides an overview of ADIZs in international law, indluding their origins and evolution. The connections between EEZs and ADIZs are also noted, together with Chinese perspectives on International Law.

The National Airspace System (NAS) is an important and a vast resource. Efficient management of airspace capacity is important to ensure safe and systematic operation of the NAS eventually resulting in maximum benefit to the stakeholders. Dynamic Airspace Configuration (DAC) is one of the NextGen Concept of Operations (ConOps) that aims at efficient allocation of airspace as a capacity management technique.

Civilian applications of Unmanned Aerial Vehicles (UAV) have rapidly been expanding recently. Thanks to military development many civil UAVs come via the defense sector. Although numerous UAVs can perform civilian tasks, the regulations imposed by FAA in the national airspace system and military equivalent agencies in restricted airspace need to be closely considered and followed in order to make progress in civilian applications.

This paper describes the approach for creating a prototype modeling and simulation syste m that captures the interactions between key participants within the National Airspace System. The current operational paradigm for the National Airspace System has nearly reached its limits and cannot accommodate the projected increases in air travel dema nd. As a result, systems -engineering practices are being used to develop and evaluate candidate operational concepts for air traffic control. As these new concepts are considered, it is imperative that adequate and credible models are available to: 1) perf orm conceptual trade evaluations covering many issues and metrics; 2) provide detailed evaluations from many viewpoints of changes to the system prior to their implementation; and 3) conduct real -time and non -real -time analyses of system -wide performance. It is planned that an effective modeling and simulation capability , known as the Airspace Concept Evaluation System, will be achieve...

This paper presents a concept for improving National Airspace System (NAS) operations through the adoption of a flexible combination of time-based traffic flow management, trajectoryorientation, and airborne separation assistance elements. Time-based traffic flow management on a NAS-wide and local level assures that local airspace areas are not overloaded at any given time. Trajectory-based operations are used to plan and execute conflict free flight paths for upcoming flight segments. Together, these operations put flight crews in a position to utilize Airborne Separation Assistance Systems (ASAS) to deal with local separation issues, if instructed or permitted by the controller to do so. The concept outlined here is derived from a broad ATM research base, along with first-hand experience and results gathered from within the framework of Distributed Air/Ground-Traffic Management (DAG-TM) research conducted over the last three years. The unique NAS traffic flow management concept proposed here draws on several existing concepts, by combining and modifying them to leverage on their particular strengths. This paper addresses the tools and technologies required and/or desirable for near-term implementation and examines the longer-term implications.

This paper describes the approach for creating a prototype modeling and simulation syste m that captures the interactions between key participants within the National Airspace System. The current operational paradigm for the National Airspace System has nearly reached its limits and cannot accommodate the projected increases in air travel dema nd. As a result, systems -engineering practices are being used

The National Airspace System (NAS) is the air traffic management system that supports flight operations around the United States. It is an example of an engineered complex system, in that it is composed of mechanical components (i.e. flights), human decision making through organizations (air transportation service providers and flight controllers), and the information flow that supports these decisions. The thesis of this paper is that representation of the NAS with all its interrelated components-mechanics, human decision making, and information flow-is a large effort involving multidisciplinary and "out-of-the-box" thinking, and thus constitutes a Grand Challenge for the modeling and simulation community.

Civilian applications of Unmanned Aerial Vehicles (UAV) have rapidly been expanding recently. Thanks to military development many civil UAVs come via the defense sector. Although numerous UAVs can perform civilian tasks, the regulations imposed by FAA in the national airspace system and military equivalent agencies in restricted airspace need to be closely considered and followed in order to make progress in civilian applications.

The NASA STI Program Office is operated by Langley Research Center, the lead center for NASA's scientific and technical information. The NASA STI Program Office provides access to the NASA STI Database, the largest collection of aeronautical and space science STI in the world. ...

The aggregate flow model is used to determine how to distribute predeparture delays among air traffic control Centers and across time to optimally satisfy constraints on airspace capacity and departure rates. To do so, a quadratic cost on cumulative departure delays is introduced, resulting in an optimization problem that can be quickly solved using convex optimization tools. Simulations using the model demonstrate the behavior of the National Airspace System (NAS) when implementing optimal departure delays for a particular constraint scenario. These results show that capacity-constrained air traffic control Centers suffer the highest delays. Three approaches for increasing the equity of the distribution of delays across the NAS are investigated. The first involves setting an upper bound on the Gini coefficient, a quasi-convex measure of inequality. Another is to make delays in some Centers more costly than in others. The last approach is to put an upper bound on the delay per departure for each Center. Simulation results demonstrate that bounding delay per departure effectively reduces the delays for the constrained Center. Enforcing an upper bound on the Gini coefficient and increasing the weight on delays in some Centers may impose large delays on other Centers when reducing the delays in the constrained Center.