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Abstract As an efficient and safe dispatching scheme is of great importance to ensure the effectiveness and safety of personnel on the Aircraft Carrier, and the towed aircraft system without bar is a common means of dispatching, the dispatching of the system is a significance and interesting question. In this paper, the towed carrier aircraft system without bar is transformed into a tractor–trailer system, and the nonlinear motion constraint is proposed. In order to improve the efficiency and safety of dispatching, the trajectory-planning and tracking of the system are studied, respectively. Obstacles in the environment and the nonlinear motion constraints are taken into consideration, the trajectory-planning is transformed into the optimal control problem, and combined with the symplecticity and pseudospectral method, an offline optimal control algorithm with high efficiency is proposed firstly. In order to accurately track the obtained trajectory, an online tracking method is proposed based on the receding horizon control (RHC) theory and the offline optimal control algorithm. Finally, the offline trajectory-planning algorithm has been proved by simulation experiment, it shows that the algorithm has high computational efficiency and good applicability. And the system can track the standard trajectory, even though there are disturbances in the environment, with high precision using the online tracking method, the calculation efficiency is also verified, and real-time tracking can be achieved. [ABSTRACT FROM AUTHOR]

Time Limited Dispatch (TLD) allows a degraded redundant system to operate for a limited length of time before repairs are required. Existing TLD analysis methods do not consider the requirement of dispatch reliability as a constraint, thus unacceptable flight delays or cancellations may occur when aircraft are dispatched following the intervals determined by existing methods. In this paper, an improved TLD analysis method with constraints of both dispatch reliability and average safety levels is proposed for Electronic Engine Control System (EECS) based on Monte Carlo simulation. Dispatch strategies for multiple fault TLD models are presented, maintenance strategies for multiple fault TLD models are discussed, and a step by step procedure of Monte Carlo simulation based TLD analysis is proposed. Finally, a case study illustrates the effectiveness of the proposed method, and a TLD analysis of an EECS is given to show the application of our method to a practical system. [ABSTRACT FROM AUTHOR]

Commercial airports are under increasing pressure to comply with the Eurocontrol collaborative decision making (CDM) initiative, to ensure that information is passed between stakeholders, integrate automated decision support or make predictions. These systems can also aid effective operations beyond the airport by communicating scheduling decisions to other relevant parties, such as Eurocontrol, for passing on to downstream airports and enabling overall airspace improvements. One of the major CDM components is aimed at producing the target take-off times and target startup-approval times, i.e. scheduling when the aircraft should push back from the gates and start their engines and when they will take off. For medium-sized airports, a common choice for this is a 'pre-departure sequencer' (PDS). In this paper, we describe the design and requirements challenges which arose during our development of a PDS system for medium sized international airports. Firstly, the scheduling problem is highly dynamic and event driven. Secondly, it is important to end-users that the system be predictable and, as far as possible, transparent in its operation, with decisions that can be explained. Thirdly, users can override decisions, and this information has to be taken into account. Finally, it is important that the system is as fair as possible for all users of the airport, and the interpretation of this is considered here. Together, these factors have influenced the design of the PDS system which has been built to work within an existing large system which is being used at many airports. [ABSTRACT FROM AUTHOR]

Purpose: Dispatch Operations Safety Audit (DOSA) is a proactive and predictive method in safety management system that detects the capabilities and pitfalls of dispatcher performance. In this study, Dispatch-Line Operations Safety Audit is carried out in an airline and results are analyzed and discussed. Design/methodology: The method of DOSA implementation for flight operations officers is similar to LOSA for flight crew. Findings: Results show that DOSA has an important effect on Threat and Error Management (TEM) in the Operations Control Center (OCC). Originality/value: Potential applications of this research include the better threat and error management in OCC with the implementation of DOSA as well as identification of threats and errors types for FOOs in OCC. Also, distribution of threats and errors in different phases of dispatch shift is discussed, therefore syllabuses of training courses can be provided with respect to threat and error types for flight operations officers. [ABSTRACT FROM AUTHOR]

Traditionally, classroom instruction has been the primary solution utilized by airlines to train Flight Dispatchers. Recently, airlines have been looking for more efficient and effective methods for training. One such strategy has been to replace classroom programmes with on-line delivered computer-based training. Facing new training strategic orientation and the pressing need for airlines to adapt to economic environments and regulatory frameworks, this paper reports the analysis of Flight Dispatchers' perspectives on what is effective Flight Dispatch training. The survey results indicate that the current Flight Dispatch training programme is effective; they do not fully support the findings from the literature that most adults prefer self-directed learning. This paper argues that Flight Dispatch computer-based training is, in certain circumstances, unable to replace Flight Dispatch classroom training. On the other hand, the literature review aligns with the research finding that computer-based training is of value toflight Dispatch trainees when it is used to complement other traditional delivery methods in Flight Dispatch training. [ABSTRACT FROM AUTHOR]

In case of considerable traffic congestion in an airport, transportation of passengers to city centre may become a challenging task, since airports are generally located far from the centre. In this study, transportation of passengers, who arrive at an airport, to the city centre has been handled. A mathematical model has been developed, which minimises total costs arising from both, the time passed, while passengers are waiting for a vehicle, and the dispatching of a significant amount of vehicles for transporting the passengers. By utilising the proposed model, in addition to matter of when to dispatch, it is also possible to specify which type of vehicles, and how many of them should be dispatched at each time interval. Ultimately, it is reported that such a plan has a great potential to enhance the productivity. [ABSTRACT FROM AUTHOR]

To resolve the problem of future airspace management under the condition of great traffic flow, high density, and small separation, a modular evolution model is built during the process of aircraft trajectory strategic planning. A state switch macroscopic Petri-net evolution model and three microcosmic Petri-net evolution models accompanied with the continuous change of aircraft speed and height in the same segment based on the aerodynamics models are presented. According to the different forms of aircraft characteristic parameter conversion and the hybrid evolution characteristics, four evolution models using differential Petri-net theory and three evolution modes using the combination of various evolution models are defined. The 4-D trajectory evolution graphs with aircraft performance constraints can be obtained by setting 10 flight segments and 15 defaults of height and speed. Theoretical analysis and simulation results demonstrate that the proposed models can enhance the versatility of trajectory prediction model and reflect the aircraft horizontal and vertical trajectory profiles precisely. [ABSTRACT FROM AUTHOR]

An optimization method for condition based maintenance (CBM) of aircraft fleet considering prognostics uncertainty is proposed. The CBM and dispatch process of aircraft fleet is analyzed first, and the alternative strategy sets for single aircraft are given. Then, the optimization problem of fleet CBM with lower maintenance cost and dispatch risk is translated to the combinatorial optimization problem of single aircraft strategy. Remain useful life (RUL) distribution of the key line replaceable Module (LRM) has been transformed into the failure probability of the aircraft and the fleet health status matrix is established. And the calculation method of the costs and risks for mission based on health status matrix and maintenance matrix is given. Further, an optimization method for fleet dispatch and CBM under acceptable risk is proposed based on an improved genetic algorithm. Finally, a fleet of 10 aircrafts is studied to verify the proposed method. The results shows that it could realize optimization and control of the aircraft fleet oriented to mission success. [ABSTRACT FROM AUTHOR]

Reducing the delays of the departing aircraft can potentially lead to improving the efficiency of surface operations at airports. This article addresses a runway-queue management problem that aims to assign the departing aircraft to runway-queues and find a departing time for each aircraft at the runway such that the total delays of all the aircraft are minimized subject to the timing, safety, en route and ordering constraints of the aircraft. Novel, local search heuristics that find runway sequences of high solution quality in milliseconds are developed for the runway-queue management problem. A mixed integer linear program that can compute an optimal solution for the runway-queue management is also presented. Computational results show that the developed heuristics run very fast and find sequences whose delays are, on average, at most 2 per cent away from the optimal cost for all the tested instances. Moreover, the heuristics are able to find an optimal sequence in at least 50 per cent of all the tested instances. [ABSTRACT FROM AUTHOR]

Demand-driven dispatch is a well-known example of a successful integration of revenue management and scheduling practices. We provide an overview of this process of dynamic capacity reallocation based on information available in revenue management systems. The reasons for revenue performance improvements are provided and existing practical approaches as well as possible ways of improvement and future development are described.Journal of Revenue and Pricing Management (2009) 8, 166–173. doi:10.1057/rpm.2008.65 [ABSTRACT FROM AUTHOR]

The article discusses the development of an aircraft systems dispatch reliability design methodology (ASDRDM). The methodology has been developed during the early phases of the aircraft systems design procedure. It also presents the validation procedure that has been performed and a case study on its use is also demonstrated.

Describes an analytical queuing model for an aircraft departure process in airports. Representation of departure demand by a nonhomogeneous Poisson process; Modeling of service times as appropriate mixtures of exponential stages; Transient analysis of the Markovian system to produce a time-dependent plot of anticipated departure delay.

A major problem for the airline industry is the assignment of airplane capacity to flight schedules to meet fluctuating market needs. Demand Driven Dispatch (D³) is an operating concept that addresses this problem. Utilizing a demand forecast which improves as flight departure approaches, aircraft are dynamically assigned to flights to better match the predicted final demands. The result, demonstrated in studies of actual airline systems, is an increase in passenger loads and revenues with simultaneously reduced costs for a net of 1-5% improvement in operating profits. Concept implementation is simplified by the prevalence of yield management systems which provide the forecasting capability, and the emergence of airplane families which provide the necessary operational flexibility. Implementation also requires frequent solution of extremely large aircraft assignment problems. These problems, which can be formulated in terms of a multicommodity network flow, can be solved with heuristic algorithms shown to exhibit an accuracy and efficiency essential to successful concept implementation. [ABSTRACT FROM AUTHOR]

This paper reviews work completed on a value-judgment-based tactical air command system intended to dispatch missions from a limited supply in response to requests for immediate close air support. A Judged Utility Decision Generator (JUDGE) assumes that value judgments can be made explicitly and in real time by appropriately trained personnel, and that decision systems should maximize expected utility. Its inputs include demand forecasts, numbers of aircraft available, and turnaround time distributions. As each request is received, JUDGE makes a dispatching decision based on the judged utility of destroying the target named in the request, kill probability data, number of sorties remaining before resupply of aircraft, and the time. In a war-game situation using experienced military subjects, JUDGE was considerably superior to a simulated current system in amount of expected utility gained. Concluding sections of the paper identify characteristics of judgment-based command systems, and discuss logical im- plications of such characteristics for system evaluation. [ABSTRACT FROM AUTHOR]

Presents a dispatch on the arts, technologies and cultures in the metropolitan community served by the Seoul airport in South Korea. Factors to consider when explaining new media to the people in the city; Reason behind the strong focus of South Koreans on relationships and unity; Social and political difficulties experienced by Korea.

The ability to conduct concurrent, multiple aircraft operations in poor weather at virtually any airport offers an opportunity to increase the rate of flight operations, an improvement in passenger convenience, and the potential to foster the growth of small airports. The small aircraft transportation system, higher volume operations concept will increase capacity at the 3400 nonradar, nontowered airports in the United States where operations are currently restricted to a "one-in, one-out" procedural separation during low visibility or ceilings. The concept's key feature is that pilots maintain their own separation from other aircraft using the air-to-air data link and onboard software within the self-controlled area, an area of flight operations established during poor visibility and low ceilings around an airport without Air Traffic Control services. While pilots self-separate within the self-controlled area, an airport management module located at the airport assigns arriving pilots their sequence based on aircraft performance, position, and Air Traffic Control intent. The higher volume operations concept uses distributed decision making and safe procedures designed to minimize pilot and controller workload and integrates with today's Air Traffic Control environment. This paper summarizes the higher volume operations concept, procedures, research, and results, as well as outlines areas in which future higher volume operations research is required. [ABSTRACT FROM AUTHOR]

Research reported in this paper is motivated by the need to better understand the structure of connectivity in air transportation networks. The aim is to investigate analysis models and techniques from modern network theory as a framework to provide both characterization of network structure and a useful systems analysis approach to derive implications from both local and global topology characteristics. Recent developments in network theory establish means to quantify topological structure in a manner that may indicate expected performance and robustness. In this paper, a mathematical footing from network theory is introduced for examining transport networks in the U.S. domestic air transportation system. Using data for the 2004 travel year, the structure of the transport network (service routes between airports) and several subnetworks is exposed in terms of degree distribution, and the importance of airports is assessed through several network measures. Useful implications are drawn from measures and further analysis that directly maps these measures to system performance is presented. The general approach is found to merit further investigation as part of a larger, more comprehensive, and design-oriented systems analysis framework for air transportation. [ABSTRACT FROM AUTHOR]

A method for deriving an Eulerian traffic flow model in real time without depending on online integration of aircraft trajectories is introduced. In this method, online model derivation starts with a baseline Eulerian airspace model, which is derived offline using historical track data. In real time, parameters of this baseline model are adapted depending on the differences in flight plans and control volume aircraft counts between the baseline model and the real world. The baseline model derivation method is based on bookkeeping of control volume aircraft counts and, hence, the model produces control decisions in terms of whole number aircraft counts, unlike the fractional counts produced by Eulerian models based on average aircraft speeds. The bookkeeping-based model indirectly retains trajectory information and aircraft identities. Hence, it serves as an excellent tradeoff between Eulerian and trajectory-based modeling approaches. Most importantly, as an improvement over previous approaches, we take into consideration the control-dependent nature of the Eulerian model while computing optimal flow-control decisions. A key feature of this model is the use of interstream jump (γ) parameters. These parameters make the model easily amenable to emulate a wide variety of control actions like rerouting. As a proof of concept, we derive a baseline model for the Fort Worth center from recorded track data for a period of 1 h on 13 March 2005 and adapt it to predict sector counts for another time period. An application of the adaptive model to optimal rerouting is also presented. [ABSTRACT FROM AUTHOR]