飞机退役时限及补充数量的预测研究

飞机的退役是航空装备管理中的重要问题之一.为科学合理地确定飞机退役时限,针对部队飞机使用情况,以某型飞机为例,对飞机的剩余寿命进行详细分析,应用统计学方法,探讨了飞机退役时限和数量的变化规律,在此基础上建立了飞机补充数量预测模型.并结合空军装备发展的实际,对飞机使用过程中的更新换代问题进行了探讨.     

作战飞机可靠性指标确定方法研究

作战飞机的可靠性决定了其完成作战任务的能力,在飞机研制阶段提出合理的可靠性指标,对提高飞机可用性和战备完好性具有重要作用.根据作战飞机实际使用需求,提出一种基于战斗出动强度的作战飞机可靠性指标确定方法,将飞机作战需求转换成和飞机出动强度有关的可靠性定量参数.     

Scatter Search and Bionomic Algorithms for the aircraft landing problem

The problem of deciding how to land aircraft approaching an airport involves assigning each aircraft to an appropriate runway, computing a landing sequence for each runway and scheduling the landing time for each aircraft. Runway allocation, sequencing and scheduling for each aircraft must ensure the scheduled landing time lies within a predefined time window and meet separation time requirements with other aircraft. The objective is to achieve effective runway use.In this paper, the multiple runway case of the static Aircraft Landing Problem is considered. Two heuristic techniques are presented: Scatter Search and the Bionomic Algorithm, population heuristic approaches that have not been applied to this problem before.Computational results are presented for publicly available test problems involving up to 500 aircraft and five runways showing that feasible solutions of good quality can be produced relatively quickly.     

飞行器结构噪声致振试验及声振耦合响应分析

以高超声速飞行器X-43A为研究对象,建立其有限元结构模型,在动力学实验室进行飞行器结构模型的固有频率测试,通过固有频率计算与试验结果对比,二者误差在1%左右,这表明所建立的结构有限元模型是比较准确的．在高声强混响室进行飞行器结构噪声致振试验,得到飞行器结构测点加速度功率谱密度(power spectral density, PSD)和舱内声场噪声声压级,通过声振耦合数值模拟计算结果与试验值对比,结果表明:数值模拟计算方法对振动噪声环境预测是比较可靠的,结构振动响应与舱内噪声响应的有限元分析与试验结果趋势上较为一致,低频段吻合较好;高频外噪声场引起的飞行器弹性腔体结构振动占据结构振动响应的主要成分,尤其是以结构低阶振动为主,而外噪声场传递到封闭腔体内的噪声也主要是通过结构腔体弹性壁板的低阶振动传播,即使外噪声激励是宽频的,封闭舱内响应噪声的频率主分量仍然是结构的低阶模态振动．     

Robust aircraft conflict resolution under trajectory prediction uncertainty

In air traffic control, aircraft velocity may be perturbed due to weather effects or measurements errors and affect trajectory prediction. We address the aircraft conflict resolution problem in the presence of such perturbations. We consider polyhedral uncertainty sets on aircraft velocity, develop a budgeted robust optimization approach and show that it is amenable to mixed-integer optimization. Numerical experiments reveal that perturbations of the order of 5% on aircraft velocities can be accounted for without significantly impacting performance.     

军用飞机维修质量管理的最优线性分派评估

在军机维修工作中,科学有效的管理,对及时完成维修任务,保障训练作战计划至关重要.在建立适合我军军机维修质量评估指标体系的基础上,定义了理想方案和贴近度,给出了排序频数的计算方法,进而将军机维修质量评估问题转化为最优线性分派问题来处理,从而为军机维修质量管理提供了一种科学、可靠的决策方法.     

飞机空中加油问题的研究

讨论了飞机的空中加油问题,通过比较不同方案下主机的最大作战半径,找到了辅机给主机空中加油的最佳方案,分析了存在多个基地时各基地的位置及辅机在各基地的数量,研究了二维坐标下主机的最佳飞行路径,给出了解决问题的办法.整个思路由浅入深,通过考虑辅机数目n分别为1,2,3,4的特殊情况进而探讨一般的规律,包括辅机在基地无加油时间和有加油时间以及主机在空中盘旋等不同假设条件下的复杂情况,并将统计出的数据列表对比,获得了更直观的认识.在最后进行了展望,希望结合实际中的飞机空中加油问题综合考虑风力、风向等随机因素的影响,拓展到3维空间的更复杂模型中,使飞机的空间加油问题变得更有实际意义.     

Strategic planning in fractional aircraft ownership programs

In the fractional ownership model, the partial owner of an aircraft is entitled to certain flight hours per year, and the management company is responsible for all the operational considerations of the aircraft and for making an aircraft available to the owner at the requested time and place. In the recent years although the industry as a whole has experienced significant growth, most of the major fractional jet management companies have been unprofitable. To increase profitability a management company must minimize its operating costs and increase its crew and aircraft utilization. In this paper, we present a methodology for efficiently scheduling the available resources of a fractional jet management company that takes into consideration the details in real world situations. We then discuss several strategic planning issues, including aircraft maintenance, crew swapping, demand increase and differentiation, and analyze their effects on the resource utilization and profitability.     

Aircraft proximity termination conditions in the planar turn centric modes

Closed-form analytic solutions for proximity management strategies are of great importance as a design benchmark when validating both automated systems and procedures associated with the design of air traffic rules. Merz (1973) first presented a solution for a set of optimal strategies for resolving co-planar co-operative encounters between two aircraft (or ships) with identical linear and rotational speeds. This paper extends the solution domain for turning aircraft beyond that of identical aircraft by presenting a rigorous analysis of the problem through a generalised optimisation approach. This analysis provides a dependable method for determining the location of the point of closest approach. This is achieved by using a vector form of Fermat’s equation for stationary points. A characteristic of this solution is the identification of a fixed reference point lying on the vector between the aircraft turn centres or on one of its extensions. This point is then used to determine where the location of the minima in the relative range between the aircraft will occur. Bounds for the domain of the solution are constructed in terms of the rotational angles of the aircraft on their turn circles. Four distinct topologies are required to characterise the types of minima that can occur. The methodology has applications in an operational context permitting a more detailed and precise specification of proximity management functions when developing algorithms for aircraft avionics and air traffic management systems.     

基于层次分析和二元语义的飞机结构安全评价研究

针对当前飞机结构的设计要求,建立了飞机结构安全的评价模型指标集,利用AHP方法提炼出4大类,14项具体指标,并确定指标权重,采用二元语义及其算子将评价语言值进行集结,对飞机结构安全进行评价.给出了评价步骤,并用实例说明该方法具有一定的可操作性,且合理可信.     

Time-indexed formulations for scheduling chains on a single machine: An application to airborne radars

Airborne radars are widely used to perform a large variety of tasks in an aircraft (searching, tracking, identifying targets, etc.) Such tasks play a crucial role for the aircraft and they are repeated in a “more or less” cyclic fashion. This defines a scheduling problem that impacts a lot on the quality of the radar output and on the overall safety of the aircraft.     

Passive detection of moving targets

This provides the conditions and equations for predicting the position and velocity of a moving aircraft as detected from a second moving aircraft.     

Collision Avoidance for an Aircraft in Abort Landing: Trajectory Optimization and Guidance

For a host aircraft in the abort landing mode under emergency conditions, the best strategy for collision avoidance is to maximize wrt to the controls the timewise minimum distance between the host aircraft and an intruder aircraft. This leads to a maximin problem or Chebyshev problem of optimal control. At the maximin point of the encounter, the distance between the two aircraft has a minimum wrt the time; its time derivative vanishes and this occurs when the relative position vector is orthogonal to the relative velocity vector. By using the zero derivative condition as an inner boundary condition, the one-subarc Chebyshev problem can be converted into a two-subarc Bolza-Pontryagin problem, which in turn can be solved via the multiple-subarc sequential gradient-restoration algorithm.     

Workforce-constrained maintenance scheduling for military aircraft fleet: a case study

The problem is related to a fleet of military aircraft with a certain flying program in which the availability of the aircraft sufficient to meet the flying program is a challenging issue. During the pre- or after-flight inspections, some component failures of the aircraft may be found. In such cases, the aircraft are sent to the repair shop to be scheduled for maintenance jobs, consisting of failure repairs or preventive maintenance tasks. The objective is to schedule the jobs in such a way that sufficient number of aircrafts is available for the next flight programs. The main resource, as well as the main constraint, in the shop is skilled-workforce. The problem is formulated as a mixed-integer mathematical programming model in which the network flow structure is used to simulate the flow of aircraft between missions, hanger and repair shop. The proposed model is solved using the classical Branch-and-Bound method and its performance is verified and analyzed in terms of a number of test problems adopted from the real data. The results empirically supported practical utility of the proposed model.     

基于战役的多机种战伤备件需求模型

为了合理储备战时航材备件,通过分析战时故障备件的需求特点,改进了传统的单机故障备件需求模型.根据多机种协同作战任务的不同,引入备件工作运行比的概念,建立了基于作战任务的多机种故障备件需求模型.为解决多机种协同作战时的保障资源配置问题提供了思路和方法.     

Network flow-based approaches for integrated aircraft fleeting and routing

Given a schedule of flights to be flown, the aircraft fleeting and routing problem (AFRP) consists of determining a minimum-cost route assignment for each aircraft so as to cover each flight by exactly one aircraft while satisfying maintenance requirements and other activity constraints. We investigate network flow-based heuristic approaches for this problem. Computational experiments conducted on real-data given by TunisAir show that the proposed heuristic consistently yields very near-optimal solutions while requiring modest CPU effort.     

Aircraft and crew scheduling for fractional ownership programs

Fractional aircraft ownership programs, where individuals or corporations own a fraction of an aircraft, have revolutionized the corporate aviation industry. Fractional management companies (FMC) manage all aspects of aircraft operations enabling the owners to enjoy the benefits of private aviation without the associated responsibilities. We describe here the development of a scheduling decision support tool for a leading FMC. We present mathematical models, exact and heuristic solution methods. Our computational results using real and randomly generated data indicate that these models are quite effective in finding optimal or near-optimal solutions. The first phase of the implementation of one of these models at the FMC led to a significant improvement in effective utilization of the aircraft, reduction of costs due to reduced empty moves, and hence increased profits.     

基于灰色关联度理论的飞机顶层设计方案优选决策模型

探讨了飞机方案设计阶段应用决策方法的重要性;建立了飞机顶层设计方案优选的层次结构和评价指标体系;应用灰色关联度理论和方法建立了方案优选的灰色层次决策模型,并利用该模型对某飞机设计方案进行优选评价和敏感性分析,得到了满意的结果     

A multivariate adaptive regression splines cutting plane approach for solving a two-stage stochastic programming fleet assignment model

The fleet assignment model assigns a fleet of aircraft types to the scheduled flight legs in an airline timetable published six to twelve weeks prior to the departure of the aircraft. The objective is to maximize profit. While costs associated with assigning a particular fleet type to a leg are easy to estimate, the revenues are based upon demand, which is realized close to departure. The uncertainty in demand makes it challenging to assign the right type of aircraft to each flight leg based on forecasts taken six to twelve weeks prior to departure. Therefore, in this paper, a two-stage stochastic programming framework has been developed to model the uncertainty in demand, along with the Boeing concept of demand driven dispatch to reallocate aircraft closer to the departure of the aircraft. Traditionally, two-stage stochastic programming problems are solved using the L-shaped method. Due to the slow convergence of the L-shaped method, a novel multivariate adaptive regression splines cutting plane method has been developed. The results obtained from our approach are compared to that of the L-shaped method, and the value of demand-driven dispatch is estimated.