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In this paper, requirements for a new aircraft designed for the regional market are presented. The design is mainly driven to fulfill the needs of the next-generation air transportation system. Today, Europe's major hubs have already reached the limit of their capacity. To facilitate the predicted growth rate of air transportation, smaller regional airports have to be integrated into the current airport network. To analyze the impact on the air transportation system, a numerical model is presented that allocates potential passengers from their place of origin to their most likely airport of choice. This passenger allocation model is used to predict future airport's growth rates and possible capacity shortages for given airport scenarios and helps to investigate the influence of the integration of new airports and a new aircraft concept into the current air transportation system. The simulation presented in this paper is based on the German airport network, but it can be easily adapted to any other national or international scenario. Requirements for an aircraft serving such smaller regional airports are directly derived from this simulation. [ABSTRACT FROM AUTHOR]

Abstract: The Workgroup Occupational Risk Model (WORM) project in the Netherlands is developing a comprehensive set of scenarios to cover the full range of occupational accidents. The objective is to support companies in their risk analysis and prioritization of prevention. This paper describes how the modeling has developed through projects in the chemical industry, to this one in general industry and how this is planned to develop further in the future to model risk prevention in air transport. The core modeling technique is based on the bowtie, with addition of more explicit modeling of the barriers needed for risk control, the tasks needed to ensure provision, use, monitoring and maintenance of the barriers, and the management resources and tasks required to ensure that these barrier life cycle tasks are carried out effectively. The modeling is moving from a static notion of barriers which can fail, to seeing risk control dynamically as (fallible) means for staying within a safe envelope. The paper shows how concepts develop slowly over a series of projects as a core team works continuously together. It concludes with some results of the WORM project and some indications of how the modeling is raising fundamental questions about the conceptualization of system safety, which need future resolution. [Copyright &y& Elsevier]

This paper presents an adaptive fuzzy control strategy for an aircraft automatic landing problem under the failures of stuck control surfaces and severe winds. The strategy incorporates a dynamic fuzzy system called sequential adaptive fuzzy inference system (SAFIS) and it augments an existing conventional controller called Baseline Trajectory Following Controller (BTFC). SAFIS is an online learning fuzzy system in which the rules are added or deleted based on the input data. Also, SAFIS incorporates an online scheme for parameter update of the membership functions. BTFC has been designed using classical control methods under normal operating conditions with winds. For this study, the following fault scenarios have been considered: 1) single fault of either aileron or elevator stuck at certain deflections, and 2) double fault cases where one aileron and one elevator at the same or opposite direction are stuck at different deflections. Simulation studies indicate that the BTFC is unable to handle these failures. Recently, Abhay et al. have proposed a neural-based scheme to augment the BTFC and its performance has been shown to be superior. However, even in this neural scheme there are gaps in the fault cases where performance specifications are not met. In this paper, results show that the SAFIS-aided BTFC improves the fault-tolerant capabilities compared with BTFC and also the earlier neural-aided BTFC performance in filling up the gaps observed earlier. [ABSTRACT FROM AUTHOR]

This paper presents the design of a missile autopilot over its flight envelop using quasi-linear parameter-varying polynomial eigenstructure assignment (PEA). The paper describes the extension of PEA to parameter-varying systems using a nonlinear missile model developed by Horton as an example. The autopilot is designed for a single-plane lateral acceleration control and a 5 degree of freedom (DOF) autopilot is also designed. Both lateral acceleration and augmented lateral acceleration outputs are considered. The lateral acceleration autopilot has nonminimum phase characteristics, and it is shown that the quasi-linear parameter-varying PEA approach can handle nonminimum phase systems unlike classic dynamic inversion techniques. Simulation results are presented over fast variations in Mach number and show that the design is robust. [ABSTRACT FROM AUTHOR]

The paper presents a universal mobile packaging line prototype as the outcome of a defence development project assigned by the Ministry of Defence of the Czech Republic. It is a facility designed for disassembling military as well as other material, and assembling supply units on standard-size disposable pallets suitable for road and air transportation. In the practical part, basic tactical-technical data of the universal mobile packaging line and its operating capabilities are determined using simulation software and the queuing theory. [ABSTRACT FROM AUTHOR]

Aeronautics and air transport is a vital sector of our society and economy. Air transport logistics is one of the key players to support efficient globalization; however, sustainable mobility is at stake, due to facts such as the interdependencies with the financial system, climate change and an increasing scarcity of resources. This paper highlights the consequences of a lack of a proper understanding of air-side and land-side, leading to an unsustainable air transport system. A system approach for knowledge sharing between air traffic controllers, handling operators, airlines and airport managers is justified by means of causal models to design a mitigation mechanism to tackle perturbations instead of increasing the latent capacity. The simulation benefits to design indicators of sustainability are also mentioned. [ABSTRACT FROM AUTHOR]

The basic task of the transportation fleets is to carry personnel and cargo from one point to another according to the daily planned flight schedule. Mission-ready flight crews and aircrafts are needed to accomplish the task. The goal of this paper is to determine which factors affect the success of the daily planned flight schedule and how, and also to define a prediction model to estimate the success of the daily planned flight schedule in order to help making more precise flight schedule. In this study, the simulation model is designed by ARENA software; the inputs defined by the NOLH experiment design, and the outputs are transferred to Design-Expert software. The effects of the factors are analyzed by Design-Expert and the prediction model is defined by using Response Surface. [ABSTRACT FROM AUTHOR]

Abstract: With increasing demand for air transportation worldwide and decreasing marginal fuel efficiency improvements, the contribution of aviation to climate change relative to other sectors is projected to increase in the future. As a result, growing public and political pressures are likely to further target air transportation to reduce its greenhouse gas emissions. The key challenges faced by policy makers and air transportation industry stakeholders is to reduce aviation greenhouse gas emissions while sustaining mobility for passengers and time-sensitive cargo as well as meeting future demand for air transportation in developing and emerging countries. This paper examines five generic policies for reducing the emissions of commercial aviation; (1) technological efficiency improvements, (2) operational efficiency improvements, (3) use of alternative fuels, (4) demand shift and (5) carbon pricing (i.e. market-based incentives). In order to evaluate the impacts of these policies on total emissions, air transport mobility, airfares and airline profitability, a system dynamics modeling approach was used. The Global Aviation Industry Dynamics (GAID) model captures the systemic interactions and the delayed feedbacks in the air transportation system and allows scenarios testing through simulations. For this analysis, a set of 34 scenarios with various levels of aggressiveness along the five generic policies were simulated and tested. It was found that no single policy can maintain emissions levels steady while increasing projected demand for air transportation. Simulation results suggest that a combination of the proposed policies does produce results that are close to a “weak” sustainability definition of increasing supply to meet new demand needs while maintaining constant or increasing slightly emissions levels. A combination of policies that includes aggressive levels of technological and operations efficiency improvements, use of biofuels along with moderate levels of carbon pricing and short-haul demand shifts efforts achieves a 140% increase in capacity in 2024 over 2004 while only increasing emissions by 20% over 2004. In addition, airline profitability is moderately impacted (10% reduction) compared to other scenarios where profitability is reduced by over 50% which pose a threat to necessary investments and the implementation of mitigating measures to reduce CO2 emissions. This study has shown that an approach based on a portfolio of mitigating measures and policies spanning across technology and operational improvements, use of biofuels, demand shift and carbon pricing is required to transition the air transportation industry close to an operating point of environmental and mobility sustainability. [Copyright &y& Elsevier]

Abstract: Assessment of unfair competitive practices in airline markets has traditionally been based on the analysis of changes in average fares, revenue and traffic following low-fare entry. This paper demonstrates the severe limitations of using such measures. In particular, our case studies show that despite very different perceptions by some analysts of apparent incumbent carrier response to entry, average fares, revenues and traffic measures showed very similar patterns of change. We then use a competitive airline market simulation to illustrate the importance of often ignored factors – revenue management and the flows of connecting network passengers on the flight legs affected by low-fare entry – in explaining the effects of entry on these aggregate measures of airline performance. These simulation results further reinforce the danger in using such measures as indicators of predatory behavior in airline markets. [Copyright &y& Elsevier]

Abstract: In recent years, concern over airport noise and its impact on surrounding communities has been spurred by a continual growth in air traffic together with urban development in close proximity to many airports around the world. This paper aims at studying the case of Hurghada airport, Egypt, with a focus on evaluating, both theoretically and practically, the airport noise and its impact on the city of Hurghada. Extensive field measurements of aircraft noise were undertaken at key locations in the city, including points lying within the premises of the Hurghada airport. The aircraft noise was also modeled using the integrated noise model (INM) in order to simulate the current and future noise levels based upon the anticipated steady increase in flight operations. Such forecasts are of particular importance for Hurghada as the number of flights is expected to grow steadily over the next decade, accompanied with an increase in urban growth for coastal resorts. Based on the actual measurements and computer simulation, noise mitigation schemes are suggested to alleviate current and future impacts. [Copyright &y& Elsevier]