A visionary look at aviation surveillance systems

The FAA's future aviation surveillance systems fall into four categories: Automatic Dependent Surveillance (ADS) will be used in the oceanic environment; ADS-Broadcast (ADS-B) will be used in the domestic en route environment; ADS-B will be used with a secondary radar backup in the terminal area; and ADS-B will be used with primary radar backup within the Airport Surface Traffic Automation (ASTA) system on the airport's surface environment. Two other systems introduced in this paper are Cockpit Display of Traffic Information (CDTI) and Traffic Advisory and Collision Avoidance System (TCAS). All these systems will use navigational signals emitted by the Global Positioning System (GPS) constellation of satellites     

Inflight path planning replacing pure collision avoidance, usingADS-B

This paper proposes a method of collision avoidance planning using automatic dependent surveillance-broadcast (ADS-B) and dynamic programming (DP). It in essence allows air traffic control (ATC) within the cockpit for remote or uncontrolled airspace and is a step toward Free Flight. This paper reviews the approach to collision avoidance in the aircraft industry and to similar problems in other industries. DP is one solution method used in other industries for the problem of path planning to avoid collisions with fixed obstacles. The solution proposed here for the aircraft case uses DP applied to the moving obstacle case. The problem is first simplified by assuming fixed obstacles for the cost minimisation algorithms. These fixed obstacles are then moved with time and the minimisation process is started again. Although this method works well in most cases, situations can be constructed where this method fails, allowing a collision. A modified approach is proposed, where the movement of obstacles is included more explicitly in the cost minimisation algorithm. This modification allows solutions which are complete and ensures safe maneuvres and should be considered as an aid to the Traffic alert and Collision Avoidance System (TCAS)     

空中交通防撞系统(TCAS Ⅱ)的排故与维护

主要以空客A320飞机为例,介绍了TCAS Ⅱ(空中交通防撞系统)系统原理、组成、功能及常见的故障、排故方法等,希望能增进对TCAS Ⅱ系统的了解,有助于TCAS Ⅱ系统的设计和维护。     

A ground and obstacle collision avoidance technique (GOCAT)

The need to provide aircrew with a timely warning of a dangerously close approach to the terrain is discussed, along with the benefits this capability is expected to provide and specific requirements that it must fulfil. The ground proximity warning techniques that are available are reviewed, and their benefits and limitations are assessed. The GEC Avionics Ground and Obstacle Collision Avoidance Technique (GOCAT) is described. The particular advantages of the GOCAT approach are identified. Because GOCAT uses a database of the terrain and obstacles around the aircraft it has a very low nuisance alarm rate but will always generate a warning when the aircraft is in a dangerous situation. Issues of parameter selection, search area definition and system limitations are examined. The results of a GOCAT simulation are presented. The system performance parameters are discussed, and database requirements are reviewed. The characteristics of a practical implementation for both civil and military applications are briefly stated     

A320系列飞机TCAS故障签派放行处置研究

空中交通警报与避撞系统(traffic alert and collision avoidance system,简称TCAS)是机载监视系统中的重要组成部分,对于避免航空器危险接近,保证航空器安全有着重要作用。针对签派工作中TCAS故障放行难点问题,分别从飞机以自身动力滑出前、以自身动力滑出后、起飞后三个阶段展开分析。首先,由于TCAS系统依托的设备多,关联系统复杂,先介绍了TCAS系统的组成以及依托设备的常见故障。其次,以TCAS的工作原理为基础,分析了各个关联设备如应答机、惯性导航和大气数据基准等故障导致TCAS故障的机理。再次,给出了关于TCAS失效能否继续实施缩小垂直间隔(reduced vertical separation minimum,简称RVSM)的说明,指出TCAS不是运行RVSM空域的基本设备,需要区分造成TCAS失效的原因。最后,从三个阶段对TCAS故障及关联设备故障展开分析,分别给出了滑出前AP/FD TCAS方式丢失、导航TCAS失效,滑出后及起飞后TCAS故障和关联系统故障并给出签派解决方案。     

对TCAS的原理分析

本文基于对防撞基本概念的理解，分析了ＴＣＡＳ工作原理，并结合实际工作过程进行了论证。     

New Concepts in Collision Avoidance Logic

Airborne collision avoidance logic is being developed to take advantage of the accurate bearing measurements provided by the Enhanced TCAS II system. This system issues horizontal and vertical resolution advisories, and should give fewer unnecessary alarms than earlier systems. Design tradeoffs and new techniques are described for threat detection, modeling of potential escape maneuvers, and the selection of resolution advisories. Plans for further development and evaluation are described.     

Slot Length and Line-of-Sight Protection

The reasoning which led to the particular slot structure defined for the collision avoidance system specified by the Air Transportation Association Collision Avoidance System Technical Working Group is discussed. The objectives were to choose a slot length that would 1) minimize the probability of interference, 2) maximize the capacity of the information channel (as measured by the number of messages received in a unit of time). Interference can be manifested by the garbling of either the collision avoidance message or the synchronization signals.     

Development of a TPS reuse library using COTS tools

In the past, functional test requirements (FTR) or test requirement documents (TRD) and test program sets (TPS) were standalone items developed by individual engineers. In some cases, one engineer would write the FTR/TRD and another would develop the TPS. Commercial ATLAS FTRs are prepared in ARINC 616 and 626 ATLAS. Military TRDs are written in IEEE ATLAS 716 versions. Previous test reuse attempts have not been successful because additional software, like browsers, is required to support these efforts. It was difficult to justify writing new software; for example, browsers to manage the application software. Today, commercial-off-the-shelf (COTS) tools are in place to browse and view information from circuit diagrams to documents to source code. These tools can develop hierarchies to organize the information. These COTS tools are available throughout Boeing on many types of workstations and personal computers on every engineer's desk. This paper discusses how a reusable test library (RTL) is being developed using commercial-off-the-shelf (COTS) tools, such as Mosaic, to address commercial and military test applications. It describes each of the tools and the process to develop TPSs using the reuse library. It defines the metrics and benefits achieved     

基于DO-178C的机载软件质量保证与管理

DO-178C 作为机载软件适航可接受的符合性标准,明确要求机载软件综合过程中必须包含软件质量保证（SQA）过程。以机载软件的软件生命周期定义、过程和数据为基础,从目标、活动和符合性评审三个方面分析基于DO-178C 的软件质量保证过程的实施;结合软件项目质量管理技术和工具,从规划软件质量管理、管理软件质量和控制软件质量三个过程研究基于DO-178C 的软件质量管理方法并给出工程实践建议。结果表明：本文将软件质量保证与质量管理紧密结合,形成了适航要求的相关证据,提供了符合需求的民用机载软件,有效保证了机载软件的质量和持续改进措施。     

TCAS 系统故障隔离及容错架构设计方法研究

针对TCAS 系统运行过程典型功能危险场景和架构设计过程,本文采用系统工程过程的正向设计流 程方法,针对潜在的功能失效风险,开展TCAS 系统域的故障检测和容错设计技术研究,形成覆盖系统、软件 和硬件层级的故障检测及隔离架构设计方案,以提高装机运行过程中防撞告警的置信度,减少由于误警和虚警 对飞行安全产生的不利影响。     

“昆仑”发动机的衍生发展

介绍了中国首次按国军标GJB241—1987《航空涡轮喷气和涡轮风扇发动机通用规范》的要求,自行设计研制成功的“昆仑”加力式双转子涡喷发动机的衍生发展。解决了与现役涡喷系列发动机安装互换性的技术难题,发展出“昆仑”A／B／H系列发动机,可满足多型飞机的动力需求;采用先进技术,增大空气流量、提高部件效率、减少压力损失,发展了推力增大型“昆仑Ⅱ”发动机;沿着“航机改燃机”捷径,改进燃气发生器,全新研制双级动力涡轮,发展了QD-128工业燃气轮机,已用于油田发电。     

基于SCADE的飞控软件的适航验证与确认

中国民用航空规章第25部对机载软件提出了适航要求,DO178B是对适航要求的符合性方法,但其中一些验证和确认目标并不适用于基于SCADE的软件验证。为此,分析了飞控软件的适航要求和符合性方法,并对基于SCADE的飞控软件的开发流程和传统的开发流程进行了分析对比,对基于SCADE的飞控软件的适航验证与确认工作提出了建议。     

PAVE PACE: system avionics for the 21st century

The PAVE PACE Initiative has been established to validate system avionics concepts for advanced military aircraft. The author presents the rationale of why the advanced architecture established by the PAVE PILLAR program should be continued under PAVE PACE to achieve: practical and affordable airborne versions of modular parallel processing network architectures for many applications currently beyond real-time implementation, readily available avionics for use in all avionics and, greatly improved techniques to reduce the cost of software development and support. An approach to the overall design structure for future avionics is also presented that entails: the use of CAD (computer-aided design) tools to assist in the development of system, hardware and software requirements, the use of replicated hardware modules (some at the wafer level), the use of reuseable software modules and the use of CAD tools to tailor hardware/software modules for specific application requirements. Continued use of the PAVE PILLAR high-speed data bus and operating system is recommended as the means to integrate and control the data input and output of physically and functionally separate parallel networks     

TCAS防撞系统空中故障分析

介绍TCAS防撞系统的工作原理及交联设备之间的关系,分析TCAS防撞系统在试飞过程中显示＂TCAS OFF＂故障的原因,并提出解决措施,以期对提高机务工作质量、降低产品故障率起到积极的作用。     

应用6Sigma改进方法提高TCAS系统可靠性

在大型民用飞机中TCAS系统是重要的飞行安全运行的航电系统之一,其故障会对飞机正常营运造成很大的影响。应用6Sigma原理进行维修管理可以有效地改进TCAS系统的可靠性。结合航空公司波音737NG机队的运行中TCAS系统故障情况,介绍运用6Sienna方法的分析过程达到的实际改进效果。     

Power management and distribution system for a more-electricaircraft (MADMEL)

A five-phase Power Management and Distribution System for a More-Electric Aircraft (MADMEL) program was awarded by the Air Force to Northrop/Grumman Military Aircraft Division in September 1991. The objective of the program is to design, develop, and demonstrate an advanced electrical power generation and distribution system for a More-Electric Aircraft (MEA). The MEA emphasizes the use of electrical power in place of hydraulics, pneumatic, and mechanical power to optimize the performance and life cycle cost of the aircraft. This paper presents an overview of the MADMEL program and a top-level summary of the program results, development and test of major components to date. In Phase I and Phase II studies, the electrical load requirements were established and the electrical power system architecture was defined for both near-term (NT-year 1996) and far-term (FT-year 2003) MEA application. The detailed design and specification for the Electrical Power System (EPS), its interface with the Vehicle Management System, and the test set-up were developed under Phase III. Phase IV, fabrication and testing of the subsystem level hardware, has been completed. Overall system level integration and testing, Phase V, is scheduled to be completed by September 1999     

民机自动飞行模式设计规范与适航性分析

民机自动飞行系统对降低飞行员工作负荷、提高飞行安全性具有重要作用.分析了自动飞行系统飞行模式设计的相关适航规范要求,研究了模式设计的基本方法和软件开发工具,以及适航符合性验证方法.开发了一种飞行模式设计与仿真平台,基于MATLAB/Stateflow设计飞行模式及其切换机制,采用MATLAB/GUI接收驾驶员操作输入,并调用飞行动力学模型进行实时仿真.形成一个集模式设计、仿真和验证一体化的闭环平台,可用于民机飞行模式的设计和适航性分析.     

Military Products From Commercial Lines

“Military Products From Commercial Lines” is a pilot program within the Air Force Manufacturing Technology Directorate's Industrial Base Pilots Office. TRW's Avionics and Surveillance Group (ASG) is leading the program. This pilot program will demonstrate commercial-military integration by producing F-22 military avionics modules on an automotive electronics production line operated by TRW's Automotive Electronics Group (AEG). To accomplish this requires a redesign of the modules so that they are producible using commercial automotive electronics processes. Dual use manufacturing also dictates establishing compatible business practices, manufacturing infrastructures and process technologies. Business practices that must be changed involve accounting procedures, contracting requirements, audit requirements and quality control. Manufacturing infrastructure improvements include incorporation of advanced concurrent engineering tools and process control software to allow economic production of small lot sizes. Process technology changes involve designing for production lines that are highly automated and compatibility with commercial practices     

基于模型的大气数据计算机实现

针对无人机用大气数据计算机,为使其满足适航审定要求,提出基于模型的实现方法。首先介绍了大气数据计算机获取适航的方式,并以获取技术标准规定项目批准书(CTSOA)为驱动,按照大气数据计算机CTSO标准提出满足最低性能标准的系统需求,将系统需求进行分解选择合适的传感器及硬件平台。随后对系统功能进行详细设计,并按照DO-178B规范完成大气数据计算机的模型搭建和仿真验证。验证结果表明,基于模型的大气数据计算机满足系统所提各项指标,开发流程符合DO-178B标准。