民用客机E化趋势及其对航电系统的影响

国外飞机制造商为了提高飞机的市场竞争力,近年来大量应用信息技术对民用飞机的操作和运营过程进行优化,民用飞机出现了明显的E化趋势。阐述了民用客机E化的现状,从E化的利益相关方、路线及目标3个方面研究和判断了民用客机的E化趋势,并分析了E化趋势对航电系统的功能、架构及安保方面造成的影响。     

Aviation electronics/avionics

International regulations prohibit aircraft from entering high-density airspace and heavily trafficked over-ocean airways without suitable avionics. The widespread use of GPS navigation and increasing complexity of passenger entertainment systems have become the latest electronics trends on large commercial aircraft. The cost of avionics plus software is approaching 50% of the total. New aircraft have multiple computers and millions of lines of software. The following sections present the most important avionics subsystems and highlight some differences between military and commercial aircraft     

An overview of Allied-Signal's avionics development in the CIS

AlliedSignal Commercial Avionics Systems (ASCAS) and its partners have established the following business objectives: short term (forward-fit and retrofit with off-the-shelf products; co-development of integrated systems); mid term (co-production of avionics products in the CIS); long term (become an integrated element of CIS aerospace industry in partnership with local firms and to maintain the necessary focus to achieve these goals). ASCAS has formed a strategic business enterprise which is dedicated to developing the avionics market within the CIS. ASCAS was fortunate to find a joint venture partner who possesses skills that complement its present core competencies. The advantage of this business arrangement is that, while expanding their experience and expertise in the area of systems integration, they can directly benefit from the expertise and capabilities of indigenous airframe and equipment manufacturers (customer knowledge, simulation and integration experience, capable/skilled manpower)     

飞机产品客户化浅析

民用飞机是特殊商品,不同航空公司以及同一航空公司的不同发展阶段,由于其产品经营理念的差别,几乎每架飞机都是与众不同的,因此飞机产品客户化是航空公司和飞机制造商共同关注的话题。空客公司的民用系列飞机获得了世界的认可,其客户选型工作可以提供很好的参考。通过研究分析空客公司的客户选型相关工作,为我国大型客机客户化设计积累必要的技术储备和参考借鉴,并为我国大型客机产品客户化提出了研究方向。     

Managing change through roadmapping [changes in aviation electronics]

Presently the USAF is operating with 90 different Model Design Series (MDS) aircraft. The 90 MDS aircraft make up a total of 5778 airframes, each with a different number of Line Replaceable Units (LRUs) which make up the avionics systems. Some of the MDSs have as few as 53 avionics LRUs while others as many as 495. The total dollar value of the USAF aircraft avionics LRUs is approximately $42.4B and $30.68B in spares. Depot repairable cost to maintain these components each year is approximately $1.2B. Each MDS is assigned specific missions and the avionics systems are developed to support those missions. Due to the evolution of mission types and user needs, change is constant for the avionics manager.     

Integrating Avionics in the Conceptual Design Phase

The avionics components of modern military aircraft significantly impact the cost and effectiveness of the total aeronautical system. In the early conceptual phase, aeronautical system designers give scant attention to designing the avionics components. The design team generally provides weight, volume and power considerations for the desired avionics functions and assumes that an avionics suite can be assembled. Less than comprehensive attention is given to the interacting effect avionics have with the other system components. In contrast, the designers expend a very large effort on finding the best balanced combination of airframe and propulsion components which satisfy the design objectives. This paper shows why avionics must be a co-equal member of the aeronautical system along with airframe, propulsion, and armament. To become a co-equal partner, avionics must be an element of the system design iterations and analysis commencing with the early conceptual design phase of a new aeronautical system.     

一种不完备粗糙集的航电设备故障诊断方法

针对已获得的航电装备测试数据中存径不完备数据的问题,在分析不完备决策表和差别矩阵属性约简的基础上,给出了一种在航电装备故障诊断中基于不完备数据获取最优诊断规则的模型,并在某型超短波抗干扰机载通信电台中应用验证,结果表明其有效性,从而为提高部队航空装备的可靠性和维修性提供了一条途径。     

Aging avionics: the problems and the challenges

Aging avionics have become a problem because aircraft are being kept in service far longer than the original plan. This paper discusses the four key problems of aging avionics: (1) determining the systems that are the high cost drivers in order to select those that should receive priority; (2) determining the requirements for the replacement; (3) identifying alternative technologies that will satisfy the requirements and are affordable; and (4) determining the funding required and acquiring the funding needed to replace the aging avionics. Challenges encountered in solving these problems include management and technical. The problem of aging avionics is not limited to a single aircraft, but occurs across all aircraft. Cost-effective modernization requires cutting horizontally across all aging aircraft, and coordination with the end users and the existing management structure. A key technical challenge is to select an architecture that is upgradeable since the funding limitations may ensure parts will become obsolete prior to the completion of a drawn-out production.     

Avionics cost of ownership

The cost of ownership of avionics includes not only the development and acquisition cost, but also the yearly operating and support (O and S) (maintenance) cost of hardware, software, and support equipment. This paper presents an avionics cost of ownership methodology developed for USAF, its data sources, and business metrics computed for USAF decision makers as we move toward operating avionics as a business. The business model is used to determine which existing avionics are candidates for replacement with new technology and to prioritize the replacements. These avionics are often used on multiple aircraft types which necessitates analysis of the causes of the high cost of ownership on each type. Databases are used to document the processing functions, data flow, and constraints of the item being analyzed. These constraints include physical, environmental, electrical, and data interfaces. Databases containing alternatives are evaluated against standard mission scenarios for aircraft utilizing these high cost avionics to determine their impact on performance, O and S costs, and mission effectiveness. The results of the foregoing analyses steps are then used in life cycle cost analyses which consider different retrofit scenarios for each alternative for each aircraft type against the avionics being analyzed for replacement. The alternatives are prioritized and a risk analysis performed considering technical, schedule, and cost growth risks. The avionics cost of ownership methodology described in this paper processes data from USAF maintenance organizations. This has revealed the very large expenditures being made to support highly unreliable avionics. These methods can be applied to all military and commercial aircraft systems to determine not only the cost of ownership of existing systems, but also the cost of ownership of new systems when they are retrofit     

民机主制造商对MBD软件供应商工程监控过程研究

基于模型的软件开发技术(Model-Based Development,简称MBD)具有可视化建模与仿真、自动生成符合适航要求的代码等特点,已在民用飞机机载设备研发领域被逐渐推广应用。越来越多使用MBD技术开发的机载软件的涌现,给民机机载软件适航符合性工作带来了前所未有的挑战。为解决这一问题,美国航空无线电技术委员会于2011年底发布了DO-178C作为民用航空界认可的机载软件符合性方法,并在此基础上发布了DO-331作为专门针对机载软件MBD技术的适航符合性要求的补充说明。通过对DO-178C和DO-331标准中MBD软件适用目标的研究,结合工程实践,总结归纳了一套民用飞机主制造商对MBD软件供应商的软件研发过程管控要求,用于在向适航当局表明符合性时提高适航置信度,以期对主制造商和供应商在处理MBD软件方面提供参考。     

Switched Ethernet testing for avionics applications

Switched Ethernet is being implemented as an avionics communication architecture. A commercial standard (ARINC-664) and an aircraft vendor-specific implementation known as avionics full duplex switched Ethernet (AFDX) have been developed that defines the topology and use of switched Ethernet in an avionics application. In avionics applications, the movement of data between devices must take place in a deterministic fashion and must be delivered reliably. All aircraft flight hardware must be tested to be sure that it will communicate information properly in the switched Ethernet network. The airframe manufacture must test the integrated network to verify that all flight hardware is communicating properly. Testing and maintenance testing is required to perform data communication level testing of switched Ethernet architectures for avionics applications to insure that all communication is deterministic and reliable. This paper provides an overview of a switched Ethernet avionics network and identifies the testing challenges associated with a switched Ethernet avionics application. A practical implementation performing the required tests is discussed.     

Data link communication equipment approved by USAF for civil air traffic control

Operations within civil airspace will transition from traditional ground-based air traffic control (ATC) to air traffic management (ATM), a concept that requires aircrews and ground managers to share responsibility of aircraft separation assurance. Increased levels of information exchange will be necessary for this concept to work safely; therefore, air-ground communications will transition from voice to data link communications. The nature of data link communications procurement requires that avionics suppliers not only verify their products meet contractual performance requirements, but also demonstrate that their products are compatible with civil communication networks and ATC. In addition, the USAF needs to demonstrate that their crew-training program is adequate to maintain the required level of aircrew proficiency and equipment can be maintained for the required level of system performance, integrity, and interoperability with the civil environment. This paper outlines some of the certification issues facing the USAF with respect to the "Approval for Use" of data link equipment to be used for communication with ATC. It will also suggest a methodology for the avionics supplier and USAF to obtain the approvals required to ensure the installation of data link communications equipment on military aircraft will remain interoperable with civil ATC.     

航空电子设备研制的测试性设计考虑

测试性是航空电子设备基本设计特性,测试性设计的好坏直接决定了航空电子设备感知自身状态(正常、故障和降级)并自动隔离内部故障的能力。从全寿命周期费用探讨了民用飞机航空电子设备开展测试性设计的必要性,给出了民用飞机研制过程中航空电子设备通用测试性设计、机内测试设计和电路及元器件的测试性设计考虑。实践证明航空电子设备开展测试性设计能有效提高民用飞机的功能安全性和维修经济性。     

设计保证体系建设和审查的专题研究之一——各国局方对设计保证体系的审定政策要求解析

对国内外适航当局对设计保证的政策法规要求和主流企业实施设计保证体系的情况进行了广泛调研和深入研究,对国际上四个主流适航当局(EASA、TCCA、FAA、CAAC)对设计保证体系要求的由来、实施背景、政策要求、与工业界的关系及未来发展趋势进行了详细分析,为我国制订相关设计保证政策、设计保证体系的建设和审查、以及国际间的协调和适航审定提供了有益的参考。     

航空电子设备直接维修成本预计方法

直接维修成本(DMC)是衡量飞机维修经济性的关键指标。整架机的DMC可以分解为各部件的DMC。介绍了航空电子设备DMC分析和控制系统,阐述了国内航电设备供应商DMC预计方面的问题,针对经验数据匮乏的问题,根据产品可靠性、维修性参数,结合航电设备的特点,提出了一种航电设备DMC预计方法。实验证明,方法不依赖于经验数据,可以较准确的预测实际DMC,适用于DMC系统运行的早期阶段。     

航空装备的完整性

 简述完整性概念在航空装备上的应用情况,提出了航空装备完整性概念,并简介了航空装备的完整性原理,     

综合航电系统实时仿真测试技术研究

研究和建设飞机综合航电系统测试是飞机研制过程中非常重要的环节。通过介绍综合航电仿真系统的原理和功能,提出了一套综合航电系统半物理仿真测试闭环试验系统的建设方案。     

飞机接口组件仿真器设计

飞机接口组件仿真器主要完成对飞机航电系统中的非1553B总线信号设备的仿真。按要求产生相应的离散量信号、模拟量信号、同步机信号等非1553B总线信号传给总线控制/信号转换器(BC/IFU)。是飞机航电系统仿真试验室进行全系统仿真关键设备。     

军机LRM及其关键技术研究

LRM(外场可更换模块)是第四代军机航电系统的主要特征,对于提高军机战备完好性和降低其全寿命周期费用有着重要意义.分析了航电系统传统结构的不足,指出了基于LRM结构的航电系统的优点,阐述了LRM的设计要求及现有标准,并深入研究了其关键技术,以便为我军新机设计提供参考.     

Use of service history for certification credit for COTS [avionic software]

Much has been written in the last ten years about how the use of commercial-off-the-shelf (COTS) components would revolutionize the aerospace industry avionics, communication, navigation, surveillance/air traffic management (CNS/ATM) as well as global air traffic management (GATM). Civil aviation authorities around the world have been faced with numerous requests to certify aircraft containing increasing percentages of COTS components, much of it never designed or intended for use in the safety critical environment of an aircraft. Product service history is one method for demonstrating that such software is acceptable for use. In theory, product service history would seem to be a fairly simple concept, both to understand and to apply. However, in practice, such use has proven extremely problematic, as questions of how to measure the historic performance and the relevance of the provided data have surfaced. This paper elaborates a research effort funded by the United States Federal Aviation Administration to collect, analyze, and synthesize what is known and understood about applying product service history. The effort is limited to the topic of software product service history as applied in the certification of airborne systems and equipment.