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The intent of this specification is for the procurement of the material listed on the QPL and, therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program shall refer to the Quality Assurance section of the base specification, AMS3961. All material qualification and equivalency data has been archived and is available for review upon request. Contact the CMH-17 Secretariat (www.cmh17.org) for additional information.

The intent of this specification is for the procurement of the material listed on the QPL and, therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program shall refer to the Quality Assurance section of the base specification, AMS3961. All material qualification and equivalency data has been archived and is available for review upon request. Contact the CMH-17 Secretariat (www.cmh17.org) for additional information.

The intent of this specification is for the procurement of the material listed on the QPL and, therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program shall refer to the Quality Assurance section of the base specification, AMS3961. All material qualification and equivalency data has been archived and is available for review upon request. Contact the CMH-17 Secretariat (www.cmh17.org) for additional information.

The intent of this specification is for the procurement of the material listed on the QPL and, therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program shall refer to the Quality Assurance section of the base specification, AMS3961. All material qualification and equivalency data has been archived and is available for review upon request. Contact the CMH-17 Secretariat (www.cmh17.org) for additional information.

The intent of this specification is for the procurement of the material listed on the QPL and, therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program shall refer to the Quality Assurance section of the base specification, AMS3961. All material qualification and equivalency data has been archived and is available for review upon request. Contact the CMH-17 Secretariat (www.cmh17.org) for additional information.

The intent of this specification is for the procurement of the material listed on the QPL and, therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program shall refer to the Quality Assurance section of the base specification, AMS3961. All material qualification and equivalency data has been archived and is available for review upon request. Contact the CMH-17 Secretariat (www.cmh17.org) for additional information.

The 747 flight test certification program was initiated with the first flight of the No. 1 airplane on February 9, 1969. Five test airplanes were used in an intensive test program involving 1443 flight hr and 36-1/4 airplane months, with the last certification flight on December 23, 1969. Full type certification approval was granted by the FAA on December 30, 1969 after a total of 10-2/3 months of flight testing. These statistics compare very well with the original program estimates, which were based on Boeing's extensive experience with development and certification testing of commercial transport airplanes. The success of this test program was not due to any great advancements in flight test techniques specifically for the 747, but was due to the tried and proven test methods developed during past certification programs at Boeing. This is not meant to imply that some new methods were not used, but to emphasize that test techniques evolve with experience.

Affordable, reliable endo- and exoatmospheric transportation, for both the military and commercial sectors, grows in importance as the world grows smaller and space exploration and exploitation increasingly impact our daily lives. However, the impact of disciplinary, operational, and technological uncertainties inhibit the design of the requisite hypersonic vehicles, an inherently multidisciplinary and non-deterministic process. Without investigation, these components of design uncertainty undermine the designers’ decision-making confidence. In this paper, the authors propose a new probabilistic design method, using Bayesian Statistics techniques, which allows assessment of the impact of disciplinary uncertainty on the confidence in the design solution. The proposed development of a two-stage reusable launch vehicle configuration highlights the means to first quantify the fidelity of the disciplinary analysis tools utilized, then propagate such to the vehicle system level.

Thermal engineering has long been left out of the concurrent engineering environment dominated by CAD (computer aided design) and FEM (finite element method) software. Current tools attempt to force the thermal design process into an environment primarily created to support structural analysis, which results in inappropriate thermal models. As a result, many thermal engineers either build models “by hand” or use geometric user interfaces that are separate from and have little useful connection, if any, to CAD and FEM systems. This paper describes the development of a new thermal design environment called the Thermal Desktop. This system, while fully integrated into a neutral, low cost CAD system, and which utilitizes both FEM and FD methods, does not compromise the needs of the thermal engineer.

The paper traces the development of the approach to airworthiness taken by Canadian government authorities from its origin through to current practices. It describes the Aerospace industry, the carriers and general aviation in statistical terms, indicates the impact of economic regulatory reform and suggests the way ahead for Canadian and other authorities lies in the attitude and methodologies practiced by the European authorities in their development of JARs. I SHOULD PERHAPS start this presentation with a short word about authorities. At the conclusion of a speech on safety regulation by Mr. Ronald Ashford of the UK Civil Aviation Authority, reported in Flight International of April 19, 1986, the following quotation from St. Paul to the Romans appeared: “You wish to have no fear of the authorities? Then continue to do right and you will have their approval, for they are God's agents working for your good”.

This paper presents the results of two static tests of structures in use on certificated aircraft and a description of finite element models of these structures. Comparisons of the results of the static tests and the predictions of the finite element analyses are given. Problems encountered in the development of the finite element models are presented, and solutions to these problems are discussed. Implementation, applications, and functional aspects of finite element analysis are also discussed. This paper does not cover the basic mathematical development of finite analysis, nor dynamic analysis applications.

Ice adhesion characterization relies heavily on experimental data, especially when dealing with fracture parameters. In this paper, a complementary framework encompassing experimental testing with the numerical treatment of the fracture variables is proposed to provide a physical description of adhesive fracture propagation at the interface of an iced structure. The tests are based on a quasi-static flexural testing setup composed of a displacement-driven actuator and an iced plate. The measured crack length and plate deflection provide the data to be analyzed by the Virtual Crack Closure Technique in order to approximate the critical energy release rate required to study adhesive fracture propagation. The critical energy release rate in mode II is under-predicted and its value is approximated using its counterpart in mode I.

The paper defines a “best” estimate of system effectiveness or reliability as one that minimizes the potential loss due to either overestimating or underestimating such a system figure of merit. A loss function is expressed in terms of the decision maker's order of preference for the consequences of either overestimation (underkill) or underestimation (overkill). However, in order for an estimate to be optimal, sufficient information at the system level should be provided. This lack or abundance of information is reflected in the variability of the measurement of system effectiveness or reliability. The variability and central tendency of this measurement are obtained from the variability and central tendency of the component data. This is achieved through the combined use of effectiveness or reliability models, Monte Carlo simulation and/or probability moments, and Bayesian statistics.

Systems such as satellites, aircrafts, automobiles and air traffic controls are becoming increasingly complex and highly integrated, as prescribed by the SAE ARP 4754 Standard. They integrate many technologies and they work in very demanding environments, sometimes with little or no maintenance, due to the severe conditions of operation. To survive such harsh operating conditions, they require very high levels of reliability, to be reached by a diversity of approaches, processes, components, etc. By their turn, the processes of analysis and decision making shall be improved progressively, as experience accumulates and suggests modifications. Most of this can be translated in models. According to this philosophy, in this work, we discuss the use of Model Based Reliability for improving the results of the Reliability Analysis and FMEA/FMECA of a satellite program, as those conducted at the National Institute for Space Research-INPE, since 1979.

This paper addresses the urgent need for adequate methodologies to use in analyzing autonomous flight systems, including Unmanned Aircraft. These systems are inherently dynamic and require analysis that is explicitly time dependent. Autonomous flight systems are becoming more commonly used, especially for Part 23 aircraft including Business (Corporate) and Regional Jets or Unmanned Aircraft deployed in hazardous environment/situation. Such systems are expected to make their own decisions under uncertain conditions caused by potential system structure changes when entering a new flight phase or switching to a new system configuration due to system degradation or failure(s) [1]. This paper highlights significant modeling errors that can arise in analyzing dynamic scenarios where these time dependencies are ignored.

The system of diffusion equations generated by SINDA is solved by an eigenmethod. This avoids the current numerical integration and its instability problems. The nonlinear terms such as radiative coupling are treated as forcing functions, and their rates of change determine the time steps, which are automatically set to yield any desired accuracy. The method can be significantly faster than the current methods. An example problem is solved in sufficient detail to allow a programmer to install the method in SINDA, so that its use would be just as convenient as calling for the Crank-Nicholson method. Existing SINDA models could be run without change, and the modelling advantages of SINDA are retained.

An automated drilling and fastening system is under development at the GEMCOR Engineering Corporation for wing manufacture on a new commercial airframe program. It is the first time that cold-working and hole inspection have been integrated into an automated fastener installation system. Numerical control and monitoring of all process parameters have been integrated in the system to achieve the greatest degree of accuracy and repeatability in fastener installation and to provide real-time, in-process statistical quality control. An integral component of the system is a capacitance probe used to measure the diameter and profile of drilled holes. Measurement information obtained with the hole probe is used to monitor the drilling process and predict tooling wear. This paper briefly discusses fastener hole requirements and the effects of hole quality on fatigue life. An overview of the capacitance measurement technique is also presented.

The parallel kinematics machine (PKM) Exechon is proposed to be used in a flexible fixture for aircraft wing assembly. The capability analysis and tests are required to investigate the suitability of the proposed fixturing solution. The research concern in this paper will be the static stiffness analysis of the Exechon device, which is a very important element of flexible fixturing solution for aircraft wing assembly using PKM. This paper will detail the experimental tests of the Exechon machine's stiffness to understand its stiffness characters and to provide validation data for Finite Element Analysis (FEA) work in developing analysis models of the Exechon device with representative stiffness characters. The preliminary FEA work in solid models and beam models with parametric modeling function will be included.