Collision risk-capacity tradeoff analysis of an en-route corridor model

AbstractFlow corridors are a new class of trajectory-based airspace which derives from the next generation air transportation system concept of operations. Reducing the airspace complexity and increasing the capacity are the main purposes of the en-route corridor. This paper analyzes the collision risk-capacity tradeoff using a combined discrete–continuous simulation method. A basic two-dimensional en-route flow corridor with performance rules is designed as the operational environment. A second-order system is established by combining the point mass model and the proportional derivative controller together to simulate the self-separation operations of the aircrafts in the corridor and the operation performance parameters from the User Manual for the Base of Aircraft Data are used in this research in order to improve the reliability. Simulation results indicate that the aircrafts can self-separate from each other efficiently by adjusting their velocities, and rationally setting the values of some variables can improve the rate and stability of the corridor with low risks of loss of separation

Throughput, Risk and Economic Optimality of Runway Landing

Abstract This paper analyzes the optimal level of operations on a single runway used only for arrivals. Two risks associated with landing procedures are the risk of a wake vortex encounter and the risk of simultaneous runway occupancy. We develop optimization models to maximize successful landing operations while mitigating these risk factors. The risks are mitigated by enforcing go-around procedures when separation distances are too small. In our capacity optimization, we assume that the goaround procedures are strictly enforced (making the operations risk-free) and their execution is absolutely safe. We develop two models as decision support tools which mimic the system dynamics and provide new insights into the landing process. One model maximizes the risk-free throughput (number of successful landings per unit of time) with and without wake-vortex effects. The second model accounts for dollar benefits and go-around costs in optimizing the system operations' level. This model maximizes expected net economic outcome (total dollar benefits minus total go-around costs) by adjusting the rate of landing attempts. Through these models, we calculate the maximum (risk-free) achievable throughput in the system. This provides a new definition of the landing capacity of the runway taking into account the probabilistic behavior of operations. Several numerical examples are given

The SISO CSPI PDG standard for commercial off-the-shelf simulation package interoperability reference models

For many years discrete-event simulation has been used to analyze production and logistics problems in manufactur-ing and defense. Commercial-off-the-shelf Simulation Packages (CSPs), visual interactive modelling environ-ments such as Arena, Anylogic, Flexsim, Simul8, Witness, etc., support the development, experimentation and visua-lization of simulation models. There have been various attempts to create distributed simulations with these CSPs and their tools, some with the High Level Architecture (HLA). These are complex and it is quite difficult to assess how a set of models/CSP are actually interoperating. As the first in a series of standards aimed at standardizing how the HLA is used to support CSP distributed simula-tions, the Simulation Interoperability Standards Organiza-tion’s (SISO) CSP Interoperability Product Development Group (CSPI PDG) has developed and standardized a set of Interoperability Reference Models (IRM) that are in-tended to clearly identify the interoperability capabilities of CSP distributed simulations

Social science in a water observing system

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95008/1/wrcr12336.pd

Review of Current State of Artificial Intelligence/Machine Learning and Other Advanced Techniques Related to Air-to-Air Collision Risk Models (CRM) in the Terminal Airspace

693KA9-20-D-00004DTFACT-14-D-00004Collision Risk Models (CRM) are used by regulatory safety agencies to determine the safe separation minima and monitor the air-to-air collision risk level of an airspace. CRMs estimate the expected number of aircraft collisions and "total" risk for a given air traffic concept-of-operation (e.g., parallel approaches). The fidelity of the models, and assumptions used in the models, are determined by the required confidence interval required for the safety analysis, the capabilities of current analytical and simulation methods, availability of empirical data sets, and the capabilities of computational resources. This paper provides an overview of the state-of-the-art CRMs for terminal area operations. Opportunities to apply recently developed artificial intelligence/machine learning (AI/ML), and data analytics methods such as analytical and rare-event simulation methods, availability of empirical data sets, and leverage available computational resources are identified

Why equity is a pipedream: Analysis of the dynamics of overscheduled NAS resources

One of the major issues in the proposed concepts-of-operations for NEXTGEN is the equitable allocation of overscheduled National Airspace System (NAS) resources. Although federal regulations, Congressional policies, and modernization plans call for equitable allocation of publicly held resources, the mechanisms for equitable allocation, and the trade-offs that must be made between stakeholders, exhibit a high degree of social, political, and economic complexity. Further, the allocations that are routinely made in Traffic Flow Management (TFM) and Air Traffic Control (ATC) are subject to widespread perceptions of systemic inequity and economic inefficiency. This paper describes the properties associated with the dynamic allocation of an overscheduled resource. The mathematical model demonstrates that (i) a natural asymmetry exists in the allocation, (ii) this asymmetry results in a low probability (≪ 10%) of an equitable allocation of resources amongst groups of flights (e.g. airlines), and (iii) increased competition reduces the likelihood of equitable allocations. These theoretical results establish the “feasible space” in which claims of equity can be made, suggests refinements of the existing allocation schemes, and establishes the framework for a regulatory role in proposed market-based mechanisms

Dynamic vs. Static Models for Erosion Control Policy Research

In recent studies of erosion control in agricultural production it has been standard practice to use timeless or static models of agricultural production processes. In this paper implications of a dynamic model of agricultural production for erosion control decision making are compared to those of a static model. On the basis of this cimparison it is suggested that future research on the economics of erosion control and erosion control policy may benefit from the use of dynamic modeling methods

Statistical Separation Standards for the Aircraft-Approach Process

Demand for air transportation has been increasing. A response to this is enhancing the runway utilization and throughput before investing on new runways or instruments. Runway throughput can be increased by reducing in-trail landing separation between aircraft, but the consequence may be an increase in the chance of a severe wake vortex encounter or a simultaneous runway occupancy (or go-around). Current instrument flight rule (IFR) standards provide fixed separation minima for given pairs of wake vortex weight classes of aircraft. In practice, the observed separation is a random variable and fluctuates near or above the specified minimum. In this paper, we propose a framework for statistical separation standards that specifies not only a lower bound for the separation but also a standard for the target value and the variance of the process. We address the question of what a more efficient separation standard is in order to control the risk in the approach process. We also consider whether separation variability may be reduced by employing such standards, i.e. more detailed standards that take the "realized variability" into account. Analytical results of this study suggest that (under specific assumptions) throughput put can be increased to some extent without degrading safety for the given facilities, infrasructure, and weather condition. The arguments and concepts are illustrated with statistical observations from Detroit airport (DTW)