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Application of Digital Computers to Air Traffic Control in the United States; Howard J. Kirshner (p. 14): "Radar-oriented tracking and alphanumeric display systems using digital computers are just now emerging as the key data processing tool in air traffic control, although the Great Falls Center, using air defense computer and display facilities, has been in operation since 1963." (p. 15) "Aircraft operations in the United States are conducted under two forms of ATC procedures. The first procedure is called Visual Flight Rules, or VFR, and the second, Instrument Flight Rules, or IFR. ... Under Visual Flight Rules, it is the responsibility of the aircraft's pilot to maintain adequate separation from other aircraft. ... The ground-based ATC system is responsible for providing separation among aircraft flying under IFR, although in clear weather the pilot also has a responsibility to see and avoid other traffic, since not all aircraft in most segments of low-altitude airspace will be under control of the ground system." (p. 16) "At 61 locations having radars and beacons, the computer-based Advanced Radar Terminal System (ARTS) is being deployed." [Editor's note: The article describes in detail the use of computers to analyze and display information that is captured by radar and beacon facilities. The impression is that none of these systems is yet (1972) ready for use but will become available soon.] [ABSTRACT FROM AUTHOR]

Commercial air travel in the United States has grown significantly in the past decade. While the reasons for air traffic delays can vary, the weather is the largest cause of flight cancellations and delays in the United States. Air Traffic Control centers utilize Traffic Management Initiatives such as Ground Stops and Expect Departure Clearance Times (EDCT) to manage traffic into and out of affected airports. Airline dispatchers and pilots monitor EDCTs to adjust flight blocks and flight schedules to reduce the impact on the airline's operating network. The use of time-series data mining can be used to assess and quantify the impact of surface weather variables on EDCTs. A major hub airport in the United States, Charlotte Douglas International Airport, was chosen for the model development and assessment, and Vector Autoregression and Recurrent Neural Network models were developed. While both models were assessed to have demonstrated acceptable performance for the assessment, the Vector Autoregression outperformed the Recurrent Neural Network model. Weather variables up to six hours before the prediction time period were used to develop the proposed lasso regularized Vector Autoregression equation. Precipitation values were assessed to be the most significant predictors for EDCT values by the Vector Autoregression and Recurrent Neural Network models. [ABSTRACT FROM AUTHOR]

The vulnerability of Positioning, Navigation, and Timing (PNT) services derived from Global Navigation Satellite Systems (GNSS) makes having a resilient and accurate Alternative PNT (APNT) based on high‐power terrestrial radio sources necessary. The L‐band is very crowded spectral real estate with GNSS, Distance Measuring Equipment (DME) and Air Traffic Control Beacon System (ATCRBS) signals occupying the band from 900–1600 MHz. Thus, as getting new signal and spectrum for APNT would be difficult, we must leverage existing transmissions and infrastructure. The ∼660 Automatic Dependent Surveillance‐Broadcast (ADS‐B) ground stations in the United States represent significant infrastructure that can be leveraged for APNT. However, as ADS‐B was designed for surveillance, it does not inherently possess features necessary to support APNT goals. This paper describes and demonstrates techniques for using ADS‐B Universal Access Transceiver (UAT) signals for PNT. We develop methods to use all ground UAT signals to provide robust, multi‐frequency pseudoranges. We examine the ranging and positioning performance of the UAT signal on the ground and in flight, to demonstrate its ranging accuracy, and hence the timing and synchronization of the station. We demonstrate and analyze navigation using UAT signals, as well as the intra‐system interference challenges of using multiple UAT stations. [ABSTRACT FROM AUTHOR]

U.S. National Airspace System modernization began with the publication of the Next Generation Air Transportation System Integrated Plan (NextGen) in 2004 to accommodate forecasted air travel demand increases in the United States. This framework proposed an integrated approach to safety, environmental sustainability, reduced fuel burn, and increased airspace and airport capacity by using automated capabilities. One of these capabilities, the Optimized Profile Descent (OPD) is an automated procedure created to link the en route phase of flight with the terminal area within the context of NextGen goals. This type of automated procedure was developed during the NextGen short phase (2004-2012) for both air traffic control and aircraft but continue to be used in a non-integrated manner. It is the confluence of incompatible automated and manual air traffic management techniques that produce a favorable location for an altitude deviation. The purpose of this study is to determine the effect of air traffic control intervention on altitude deviations reported during optimized profile descent arrival procedures in the U.S. National Airspace System from January 1, 2012 to January 1, 2018. Examination of aviation safety reports from this time period showed that air traffic control intervention did affect altitude deviations, specifically in the areas of aircrew error, communication error, and equipment malfunction or limitation. This analysis also demonstrated the failure of the altitude deviation rate to return to normal historic levels after the introduction of NextGen procedures, making altitude deviation a leading safety indicator for the U.S. National Airspace System. [ABSTRACT FROM AUTHOR]

This note provides a survey of the practice of States on ADIZs. It is found that while some ADIZs are entirely within territorial airspace, most extend beyond the outer limit into the airspace above the EEZs and even the high seas; and in the part beyond territorial airspace, transiting aircraft are prevalently subject to identification. Transiting military aircraft, which most of the time refuse to identify themselves voluntarily by submitting a flight plan or reporting their positions, may nevertheless be identified passively through radar detection, radio communication or close visual check. As most ADIZs are within the claiming State's FIRs, transiting civil aircraft can be identified "unconsciously" through civil air traffic control. Where an ADIZ extends beyond the claiming State's FIRs, most transiting civil aircraft comply with voluntary identification measures, presumably due to the light extra burden incurred. The non-compliant are easy to identify through passive means such as radar detection and radio communication, with the use of close visual check highly unnecessary. [ABSTRACT FROM AUTHOR]

Weather-related delays are among the most common in aviation and are frequently the result of low visibility or cloud ceilings, which cause landing aircraft to be spaced farther apart for safety, reducing the capacity of an airport to land aircraft in a timely fashion. Using 45 years of archived surface observations from 30 of the busiest airports across the United States, the prevalence of low-visibility and low-ceiling conditions is examined, along with the meteorological conditions that support them and the associated trends over time. It is shown that these conditions are becoming less frequent at most locations—for many significantly so—and that this decrease can be seen at all times of day and in all seasons. [ABSTRACT FROM AUTHOR]

The European Union project of Single European Sky initiated a reorganization of European airspace and proposed additional measures for air traffic management to achieve the key objectives of improving efficiency and capacity while at the same time enhancing safety. The concept of multiple remote tower operation is that air traffic controllers (ATCOs) can control several airfields from a distant virtual control centre. The control of multiple airfields can be centralised to a virtual centre permitting the more efficient use of ATCO resources. This research was sponsored by the Single European Sky ATM Research Program and the ATM Operations Division of the Irish Aviation Authority. A safety case was developed for migration of multiple remote tower services to live operations. This research conducted 50 large scale demonstration trials of remote tower operations from single tower operations to multiple tower operations for safety assessment by air navigation safety regulators in 2016. A dedicated team of air traffic controllers and technology experts successfully completed the safety assessment of multiple remote tower operations in real time. The implementation of this innovative technology requires a careful balance between cost-efficiency and the safety of the air traffic control in terms of capacity and human performance. The live trial exercises demonstrated that the air traffic services provided by the remote tower for a single airport and two medium airports by a single ATCO with ‘in sequence’ and ‘simultaneous’ aircraft operation was at least as safe as provided by the local towers at Cork and Shannon aerodromes. No safety occurrence was reported nor did any operational safety issue arise during the conduct of the fifty live trial exercises. [ABSTRACT FROM AUTHOR]

The operation of small unmanned aerial systems (sUAS) in the National Airspace System requires a careful consideration of the operating philosophies to ensure a safe outcome for all users. Small UAS operations are explored while the associated risks and benefits from the operations are reviewed. The operation of sUAS in self-separation airspace is discussed by an examination of the concept of autonomous flight rules (AFR). This includes a presentation of the basic principles of AFR and an explanation of the requirement for a sense-and-avoid system. Current and future uses of sUAS are presented to highlight the benefits from their use. Finally, an overview of the major risks associated with the operation of sUAS is provided in the form of a risk assessment matrix and a hazard/risk process decision chart. Mitigation actions to reduce the risks are also specified along with recommendations for further study. [ABSTRACT FROM AUTHOR]

Flight on-time performance is one of the most important issues in the National Airspace System, a very complex and dynamic system. To avoid negative impacts to the aviation industry, the Federal Aviation Administration has set a long-term objective of understanding and mitigating flight delays. Building an effective and accurate prediction model of flight-delay incidents will help airport executives make the best decisions in delay scenarios. This article utilized two advanced prediction methods to predict the probability of a flight-delay incident--data mining using the decision tree and data mining using Bayesian inference. Prediction models were built using flight on-time performance data collected from different sources. The results indicated important airport-related factors and their effects on the flight on-time performance. [ABSTRACT FROM AUTHOR]

We propose a robust optimization approach to minimize total propagated delay in the aircraft routing problem. Instead of minimizing the expected total propagated delay by assuming that flight leg delays follow specific probability distributions, our model minimizes the maximal possible total propagated delay when flight leg delays lie in a prespecified uncertainty set. We develop exact and tractable solution approaches for our robust model. The major contribution of our model is that it allows us to explicitly model and handle correlation in flight leg delays (e.g., because of weather or various air traffic management initiatives) that existing approaches cannot efficiently incorporate. Using both historical delay data and simulated data, we evaluate the performance of our model and benchmark against the state-of-the-research stochastic approach. In most of the cases, we observe that our model outperforms the existing approach in lowering the mean, reducing volatility, and mitigating extreme values of total propagated delay. In the cases where a deficit in one of the three criteria exists, gains in the other two criteria usually offset this disadvantage. These results suggest that robust optimization approaches can provide promising results for the aircraft routing problem. [ABSTRACT FROM AUTHOR]

Optimized profile descent (OPD) is an arrival procedure for the Next Generation Air Transportation System, which has been demonstrated to effectively decrease noise, emissions, and fuel costs. Implementation of OPD operations requires effective metering policies because of the increased role of uncertainty in aircraft trajectories during descent. While optimal sequencing and spacing of OPD flights have been studied in the literature, any potential savings resulting from possible changes in metering point configurations have not been addressed. In this paper, we develop models to further increase the value of OPD operations over conventional arrival procedures by optimizing metering point configurations, which include identification of the optimal number and locations of metering points to use during OPD. We derive an algorithmic framework based on implementations of a stochastic dynamic programming model and a nonlinear stochastic integer program to identify best metering point configurations where resulting computational difficulties are addressed through convex approximation and Lagrangian decomposition procedures. We also describe numerical results based on actual traffic information at major U.S. airports, which indicate that the total potential savings in the top 10 major airports could be up to $22 million a year if the proposed policies are implemented. [ABSTRACT FROM AUTHOR]

The article discusses how local governments can help protect the safety of manned flight in the vicinity of airports in the U.S. Topic discussed include manned flight conflicts in the National Airspace System (NAS) near airports; regulation defined Federal Aviation Administration (FAA) concerning unmanned aerial system (UAS).

The Department of Defense and Department of Homeland Security use many threat detection systems, such as air cargo screeners and counter-im provised-explosive-device systems. Threat detection systems that perform well during testing are not always well received by the system operators, however. Some systems may frequently "cry wolf," generating false alarms when true threats are not present. As a result, operators lose faith in the systems--ignoring them or even turning them off and taking the chance that a true threat will not appear. This article reviews statistical concepts to reconcile the performance metrics that summarize a developer's view of a system during testing with the metrics that describe an operator's view of the system during real-world missions. Program managers can still make use of systems that "cry wolf" by arranging them into a tiered system that, overall, exhibits better performance than each individual system alone. [ABSTRACT FROM AUTHOR]

The article focuses on the issues surrounding accidents in commercial space, and discusses steps taken by the U.S. in addressing the same. Topics discussed include enactment of Commercial Space Launch Competitiveness Act in 2015 for addressing commercial exploration and exploitation of space resources; analysis of Federal Aviation Administration's (FAA) air traffic management system; and Convention on International Liability for Damage Caused by Space Objects.

The Next Generation Air Transportation System or 'NextGen' is a series of programmes designed to transition the National Airspace System from a radar-based, air traffic controlled system to a satellite-based, air traffic managed system. NextGen programmes aim to improve the efficiency and predictability of gate-to-gate operations. They are also designed to support capacity management at large, congested airports and to foster better access in and out of busy metropolitan areas where the proximity of commercial and general aviation airports may create some challenges for air traffic controllers in approach and departure paths. This paper measures changes in four endogenous delay-related variables based on flight plan (on-time gate arrival, airborne, taxi-out and block delays) that affect different phases of a flight (arrival, en route, surface movement and gate-to-gate) when ceiling and visibility are in instrument meteorological conditions. Because of the interdependence of the variables in explaining performance outcomes, this study compares an ordinary least squares model with two-stage and three-stage least squares models to evaluate changes at Houston George Bush Intercontinental Airport (IAH) after the implementation of new procedures and routes on 29th May, 2014. Average excess miles flown and gate arrival delays represented the impact multipliers that affected the most the four endogenous variables before and after the implementation of new procedures and routes. [ABSTRACT FROM AUTHOR]

The article highlights the air traffic control and aircraft safety innovations developed in Indiana during the 20th century. Topics discussed include the Civil Aviation Administration's establishment of the Indianapolis Experimental Station, the adoption of U.S. technologies as international safety standards, and the success of engineers and scientists at Indianapolis in enhancing aviation safety.

One of the key elements to NextGen is the transition from the current ground- based radar monitoring system to a satellite-based system using the Automatic Dependent Surveillance-Broadcast System (ADS-B). The FAA has set a mandate which requires all aircraft to be ADS-B equipped by the year 2020 in order to continue operating in the National Airspace System. However, the FAA has not set forth any training requirements for aviation instructors or designated examiners. This study looked at how ADS-B is currently being taught among aviation educators across the United States and how important this training is to current aviation curriculum. With the information collected, it was determined that only a minimal amount of ADS-B training is currently taking place across the country, and the training that is taking place is non-standardized and limited due to the perception that ADS-B is only to be used as a traffic advisory tool. There was significant difference in the perceived importance of ADS-B, t(73) = -2.79, p < .01 between the flight instructor group and the group containing mostly professors and administrators. Also, a significant difference was found in the comparison of perceived importance and institution, t(73) = -3.11, p < .01. There was no significance found when comparing the perceived importance of ADS-B training to the number of years a respondent had worked as an aviation educator, F(1,73) = .44, p = .508 or the number of hours a respondent had received ADS-B training, F(1,60) = .15, p = .699. There was also no significant difference in the perceived importance of ADS-B training dependent upon if participants operated in a geographic location that had ADS-B coverage, t(73) = -1.88, p = .063. Several factors were discovered as to why there seems to be no current urgency among aviation educators to train their students in this new technology. In addition, recommended steps the FAA could take in order to help aviation educators with the ADS-B training process were suggested. [ABSTRACT FROM AUTHOR]

The article presents a study that investigates a cirrus contrail model to predict and to simulate the large contrail ensemble properties as meteorology and air traffic functions in the U.S. Researchers used a plume Lagrangian Gaussian model and mixed it with cloud processes. It mentions the individual contrail equations, model assumptions and analysis of contrail cirrus background. Moreover, results of the study are mentioned.