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This paper discusses the US Air Force/Bell Aircraft Corporation X-2 project which began in 1945. It was aimed at developing a research aircraft designed to reach speeds of over Mach 3 and altitudes over 100,000ft. A brief description of the aircraft is given along with a discussion of its flight test programme. The much-delayed project ended on 27 September 1956 during the aircraft's 13th powered flight. Loss of control at over Mach 3 led to violent motions characteristic of inertia roll coupling, following which both pilot and aircraft were lost. The paper concludes with an examination of the limited achievements of the project and lessons learned from it.

This paper deals with aspects of the British Aircraft Corporation TSR2 programme designed to produce for the Royal Air Force a supersonic low-level nuclear strike and reconnaissance aircraft for service entry in 1964. A short background to the project is given, together with a brief history of the progression of the programme. Reference is made to mission requirements, selection of the powerplant, the development of the configuration, mission avionics, and the brief flight test programme. The paper concludes with a discussion of the main problems encountered over the life of the project and (hopefully) the lessons learned.

This paper will provide an overview of the International Space Station (ISS) Environmental Control and Life Support (ECLS) design of the Crew Health Care System (CHeCS) Rack 1 and it will document some of the lessons that have been learned to date for the ECLS equipment in this rack.

With the DC-10 carbon-epoxy rudder, the Douglas Aircraft Company achieved one of the greatest percentage weight savings associated with composite structures. Apart from minor damage from lightning strikes, the 15 rudders put into service have experienced virtually trouble-free operation for about a decade. This paper explains why a multirib, postbuckled skin design was used for the DC-10 composite rudder, how it was justified, and how it would have compared with more conventional sandwich design concepts. Special attention is devoted to the reasons why, for such postbuckled designs, it is better to allow the skin to wrinkle and unload itself than to reinforce it and make it resist buckling until some higher load level is attained. With minor changes in the manufacturing technique, this design concept is ideal for the control surfaces on many aircraft. The paper includes suggestions on how to make even better composite control surfaces in the future.

In 1997 the SAE ITS Safety and Human Factors Committee identified the operation of navigation and route guidance systems while driving as a priority area for standard development. A review of visual and task demands was the foundation for the subcommittee to develop a recommended practice using Static Task Time. Many product development organizations had great interest in whether there would be limitations imposed on the operation of navigation systems while driving. This paper addresses the lessons learned in establishing a sound basis for the development of a standard, addressing issues raised, and resolutions leading to the final approval.

The International Space Station (ISS) has served as an excellent test bed for the implementation and integration of several life support systems, and has offered many lessons that can be applied to future vehicles and program. This paper focuses on those lessons learned within the Environmental Control and Life Support (ECLS) Water Subsystem, which have dictated on-orbit system performance and forced many operational controls. These include lessons on the need for precise documentation and testing, pros and cons of different types of storage containers, and the need for designing systems to have accessibility and flexibility. This paper describes the issues encountered on ISS and suggests solutions for future systems in the form of recommendations and questions posed to the future designers.

The lead battery industry's proactive approach to working with state and federal regulators on environmental regulatory and legislative issues has proven to be a successful tool in producing a high recycling rate for lead-acid batteries. The reverse distribution system set up by the battery industry to collect and recycle lead-acid batteries alleviates the concerns raised by governmental agencies and environmental groups over how the batteries are handled. Not only does the industry benefit from better public relations as a result of their commitment to ensure a high recycling rate, it also provides a reliable source of recyclable materials necessary to operate battery recycling facilities.

Metop (METeorological OPerational satellite) is a series of three satellites designed to monitor the climate and improve weather forecasting. This paper describes the thermal analysis, thermal testing performed, and relevant lessons learned. For the thermal analysis campaigns it focuses on: exchange and correlation of reduced thermal mathematical models established in various software formats sizes and content of the models, in particular automatic generation of reduced models from the detailed models uncertainties definitions of thermal interfaces The lessons learned from the thermal testing campaigns apply to: selection of test environment, using solar simulation and/or infra-red techniques selection of test cases based on thermal design driving parameters and/or test chamber capabilities adequate instrumentation (i.e. thermocouples, test heaters) for all critical components (un)expected events e.g.

In the spring of 1991, the business teams of Hughes Communication and Thomson Consumer Electronics asked the question of whether a satellite TV system with an 18″ dish could be a viable consumer product. Would people pay for what was previously “free” and could the market be expanded from the rural un-served to the perceived metro underserved? Betting that consumers would pay for higher quality and more compelling entertainment, the dice was rolled. That bet more than paid off with the satellite TV industry growing to more than twenty million subscribers. Satellite radio now faces the same questions, but history has already passed judgment on its ultimate success. The question is no longer whether it will succeed, but exactly how great is the opportunity. Satellite radio will not only fulfill its promise of offering a wide range of lean back entertainment options, but also the potential for new lean forward services.

This paper will provide an overview of the International Space Station (ISS) Environmental Control and Life Support (ECLS) design of the Node 1 Fire Detection and Suppression (FDS) subsystem and it will document some of the lessons that have been learned to date for this subsystem.

This paper will provide an overview of the International Space Station (ISS) Environmental Control and Life Support (ECLS) design of the Node 1 Sample Delivery Subsystem (SDS) and it will document some of the lessons that have been learned to date for this part of the subsystem.

A global optical survey of the solar corona (ref 1) is presently accomplished by observations made with an Extreme ultraviolet Imaging Telescope (EIT), an experiment on-board of SOHO. The thermal issue was a main concern for this sensor. The thermal behaviors of the instrument and some subsystems have been extensively analyzed and tested; these can now be compared with the real behavior in space. These analyses and tests are reported. We outline the lessons learned from this experience for the thermal design of future scientific instruments and suggest improvements in the presently used methods as well as hand calculation methods which enable to easily model some specific problems and more directly extract the physical aspects of the problem.

The Wide Field Camera 3 (WFC3) instrument has undergone two complete thermal vacuum tests (TV1 and TV2), during which valuable lessons were learned regarding test configuration, test execution, model capabilities, and modeling practices. The very complex thermal design of WFC3 produced a number of challenging aspects to ground testing with numerous ThermoElectric Coolers and heat pipes, not all of which were functional. Lessons learned during TV1 resulted in significant upgrades to the model capabilities and a change in the test environment approach for TV2. These upgrades proved invaluable during TV2 when pre-test modeling assumptions proved to be false. Each of the lessons learned relate to one of two following broad statements: 1. Ensure the design can be tested and that the effect of non-flight like conditions is well understood, particularly with respect to non passive devices (TECs, Heat Pipes, etc) 2.

A primary purpose of the STOL/Maneuver Technology Demonstrator program was to design, develop and demonstrate an integrated flight/propulsion control (IFPC) system. This system is intended to utilize the control power of all available control effectors in the control of the aircraft flight path in all parts of the aircraft envelope, on the ground as well as in the air. To accomplish this task, an integrated design and test effort was required, with the supplier of each component participating in the deliberations at all points in the program. The intent of this paper is to describe the requirements and goals of this team-oriented effort and the management techniques used to integrate both the hardware and software and the efforts of the multitude of agencies involved in the program.

From a quarter to one half of all projects that fail to meet their imperatives of cost, performance/quality or schedule are in some way associated with missing, poorly written or misunderstood requirements (1). This results in re-design, re-test and continual frustration to both the originator and the user of these requirements. Thus, a process for generating complete, consistent, unambiguous and verifiable requirements is essential to today’s automotive development process which focuses on “fast to market” and “doing it right the first time.” Lessons learned from evaluating the customer, internal and supplier requirements specifications show that the following requirement deficiencies regularly occur – Hidden Incomplete or unclear Incorrect Ambiguous Missing Unknown Secret (competitive sensitive) Unknown Correlations.

The SAE AS2C Standard AS5506C Architecture Analysis and Description Language (AADL) is a modeling language for predictive analysis of real-time software reliant, safety and cybersecurity critical systems that provides both the precision of formal modeling and the tool-agnostic freedom of a text-based representation. These traits make AADL ideal for virtual integration, a process that enables early detection of integration defects through model integration of software, computer hardware, and interacting physical devices. AADL supports multiple domains of architectural analysis such as timing, latency, resources, safety, scheduling, and cybersecurity. Adventium Labs conducted an exercise to determine the applicability of software engineering practices (e.g., continuous integration (CI), application programming interface (API) sharing, test driven development (TDD)) to the AADL-based Architecture Centric Virtual Integration Process (ACVIP).

United Airlines has been operating long range, two-engined aircraft in ETOPS (Extended Range Operation with Two Engine Airplanes) for almost nine years. During that time, the shared industry experience and in-service operating results have created changes in the maintenance program and plan, and led to policies which have altered fleet operations. With an emphasis on safety-of-operations, this paper identifies lessons learned from experience and it also documents the adjustments to the maintenance program and policies.

From August 1998 to July 2000 the author was responsible for design, fabrication and deployment of the Flashline Mars Arctic Research Station (FMARS). This project was to be the first planetary analog facility, enabling high fidelity operational simulation and equipment testing in a setting visually and geologically similar to Mars. Funding for the project would be obtained privately through the Mars Society and NASA would be the principle user. However, procedural difficulties during design and fabrication, destruction of construction materials resulting from a paradrop failure and contractual disputes resulted in deployment of a non-optimal facility, not acceptable to NASA and having a potentially limited operational life. This paper is an attempt to review the design / fabrication / deployment process of the FMARS, identify events leading to problems and failures and make recommendations to assist in similar future projects.

This paper outlines Pi Technology's approach to testing high-reliability automotive software. Based on data collected during an engine controller development, it discusses the value of different types of testing at various stages of the design process and when errors are found. The team structure used for embedded systems is discussed to provide the context in which software development occurs.

AIRCRAFT engines have taught engineers many valuable lessons, some of which may well be applied to the design of ground vehicle engines. These lessons are discussed here in detail by Mr. Young, who considers both the general lessons to be learned, such as the stress laid by the aircraft engineer on the importance of attention to even the minutest detail; and the specific lessons, such as the importance of good volumetric efficiency and how it is obtained by attention to valve port size, valve lift, and manifolds. Mr. Young warns, however, that aircraft-engine practice should not be followed too closely, so that the result would be considerable structural flexibility that might be detrimental in certain ground vehicle engines.