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Carbon fiber-reinforced plastic (CFRP) is one of the most commonly used materials in the aerospace industry today. CFRP in pre-impregnated form is an anisotropic material whose properties can be controlled to a high level by the designer. Sometimes, these properties make the material hard to predict with regards to how the geometry affects manufacturing aspects. This paper describes eleven design rules originating from different guidelines that describe geometrical design choices and deals with manufacturability problems that are connected to them, why they are connected and how they can be minimized or avoided. Examples of design choices dealt with in the rules include double curvature shapes, assembly of uncured CFRP components and access for non-destructive testing (NDT). To verify the technical content and ensure practicability, the rules were developed by, inter alia, studying literature and performing case studies at SAAB Aerostructures.

The EUROMIR-95 flight was selected as model for the HUBES experiment: a similar duration (135 days), a similar crew (3 men), similar schedule organisation (8 hours work, 8 hours sleep, 8 hours off-duties), similar workload for the crew and the mission control (performance of scientific experiments), similar setup for communication and data processing, and similar layout of the MIR station, as the simulation was performed in the MIR simulator located at the Institute for BioMedical Problems (IBMP) in Moscow. The Scientific Programme of HUBES had been elaborated by integration of 31 experiments from more than 80 research proposals from Principal Investigators from Europe, USA and Russia, in domains of Physiology, Psychology, Operations and Technology.

Governmental assurance documentation bibliography updated; new tabulation effective as of April 1, 1967. Latest revision indicated in all instances, but no attempt was made to list supplements or amendments. Department of Defense Index of Specifications and Standards (DODISS) published annually in three parts (alphabetic, numerical, and listing of Federal Supply Classification following unclassified documents.

The potential contributions of acoustical technology to manufacturing companies pervade nearly all of its functions from marketing and product planning to design engineering and quality control. Despite this, however, companies generally feel uneasy when they embark on programs to use acoustics in their operations because the technology seems complicated and somehow harder to “get a handle on” than it is in other cases. But the issues of product sound, and the benefits of acoustics on a diagnostic tool are too important to ignore, so in this paper we discuss these issues in a “20 questions” format to help planners, engineers and managers as they proceed to implement acoustical technology in their organizations.

The Ultimate GD&T Pocket Guide explains the most common rules, symbols, and concepts used in geometric dimensioning and tolerancing. ...This one-of-a-kind reference guide includes over 100 detailed drawings to illustrate concepts, more than 40 charts for quick reference, explanations of each GD&T symbol and modifier and much more...Written by standards expert Alex Krulikowski, this valuable on-the-job reference clarifies how to interpret standard-compliant technical drawings that use ASME Y14.5-2009.

EXCLUSIVE MEMBER BENEFIT: 2016 MOBILITY ENGINEERING PROFESSIONAL SALARY SURVEY AND CALCULATOR Gain better insight into compensation practices: this salary survey is the only study its kind to explore levels and changes in compensation and employment for engineers and technical employees in the automotive, aerospace, and commercial vehicle industries. It benchmarks compensation levels based by geography, education, industry sector, experience, and managerial and budgetary responsibility. The full report is available to SAE International members by signing into your My SAE account and downloading it into your My Library area. Members also have full access to the updated online interactive salary calculator by visiting SAE’s website. Become a member of SAE International to access this exclusive benefit for free, or purchase it today. YOU BELONG HERE. Membership helps you succeed both personally and professionally. Join us today.

On January 14, 2004 President George W Bush outlined a new vision for NASA that has humans venturing back to the moon by 2020. With this ambitious goal, new tools and models have been developed to help define and predict the amount of space radiation astronauts will be exposed to during transit and habitation on the moon. A representative scenario is used that includes a trajectory from LEO to a Lunar Base, and simplified CAD models for the transit and habitat structures. For this study galactic cosmic rays, solar proton events, and trapped electron and proton environments are simulated using new dynamic environment models to generate energetic electron, and light and heavy ion fluences. Detailed calculations are presented to assess the human exposure for transit segments and surface stays.

The scope of this Standard is the definition of the response of a numerically controlled machine to a valid sequence of records made up of 32 bit binary words or ASCII text strings. The Standard defines the structure of these records and of the 32 bit binary words or ASCII text strings which make up the records. This standard addresses the control of machines capable of performing 2, 3, 4, and 5 axis motion of an active tool (mill, laser, pen, etc.) relative to a part, and those capable of 2 and 4 axis tool motion relative to a rotating part (turning machines), including parallel tool slide sets capable of concurrent (merged) motion.

The need to improve quality while reducing cost in aerospace manufacturing is requiring new manufacturing methods and processes. Advanced technologies, such as 3D Image Metrology, offer great potential to lean manufacturing, if properly integrated into the production process. Over the last years 3D Image Metrology has developed a level of performance, which make it ideally suited for this purpose. These capabilities include the automatic in-process inspection of tools and parts before machining, machine control for highly accurate positioning during the machining operation, and in-process inspection during machining. This offers jig-less assembly, lower inventory, faster part throughput, and many more advantages.

This SAE Aerospace Information Report (AIR) describes field-level procedures to determine if 400 Hz electrical connections for external power may have been subjected to excessive wear, which may result in inadequate disengagement forces.

This paper introduces the characteristics of the 4 wheel independent driving/4 wheel independent steering (4WID/4WIS) electric vehicle (EV). Models of Subsystems and the vehicle are constructed based on Matlab/simulink. The vehicle model allows the inputs of different drive torques and steer angles of four wheels. The dynamic characteristics of drive motors and steer motors are considered, and also it can reflect the vehicle longitudinal dynamics change due to the increase of the mass and inertia of the four wheels. Besides, drive mode selection function that is unique to this type vehicle is involved. Simulations and analyses of crab, oblique driving and zero radius turning which are the special conditions of 4WID/4WIS EV are conducted. The results show that the model can reflect the dynamic response characteristics. The model can be used to the simulation analyses of handling, stability, energy saving and control strategies verification of 4WID/4WIS EVs.

Unguided sounding rockets, also known as sub-orbital rockets, are vehicles that carry scientific experiments and/or sensors to collect data during their trajectory. These rockets lack active control but are capable of traversing the Earth’s atmosphere. It is crucial to thoroughly analyze the flight parameters during the preliminary design phase. The Open Rocket flight simulation software, developed by Sampo Niskanen, is a widely used open-source project. However, it has some simplifications in comparison to its documentation. It does not specify the calculations of critical parameters required for the rocket’s stability during its flight. Additionally, it does not calculate data related to dynamic stability, which encompasses the system’s ability to make disturbances corrections during the rocket’s trajectory. Consequently, this study presents a flight simulation of a rocket with 6 degrees of freedom using Matlab/Simulink.

New approaches to problems such as noise, temperature control of accessories and equipment in the nacelle, as well as improved safety features, are necessary in a modern high by-pass engine installation. The means of supporting the engine, cowling design, and maintainability features combine to improve the state of the art that a more economic airplane will result.

The Automated Spar Assembly Tool (ASAT II) at the Everett, Washington, 777 Boeing manufacturing facility could be the largest automated fastening cell in the commercial aircraft industry. Based on the success of the ASAT I, Boeing's 767 spar assembly tool, the 285-foot long ASAT II cell was needed to accurately position and fasten the major spar components (chords and web), then locate and fasten over 100 components (ribposts and stiffeners) to assemble the 777 forward and rear wing spars. From its inception in 1990 to the first drilled hole in January 1993 and through two years of spar production, the more advanced ASAT II has proven to be a greater success than even its 767 ASAT I predecessor. This massive automated fastening system consistently provides accurate hole preparation, inspection, and installation of three fastener types ranging from 3/16 inches to 7/16 inches in diameter.

Wing panels for Boeing's new 777 airplane are assembled using fastening machines called Wing Fastener Systems (WFS). Compared to the wing riveting machines currently used to squeeze rivets for other airplane models, the 777 WFS provides significantly more features in that it also installs two part fasteners, collects process data for Statistical Process Control analysis, plus other functions. Historically, new operators for wing riveting machines have needed six months of on-the-job training to achieve basic qualification. Because of the increased functionality of the 777 WFS, an eight to nine month O.J.T. requirement was anticipated. Training requirements were further compounded by our need for up to thirty qualified operators in a relatively short time frame and a maintenance staff thoroughly trained in the new control architecture. Boeing's response to this challenge was to use simulation methods similar to those used to train pilots for our customer airlines.

In the frame of the CRYOSYSTEM A-phase study financed by the European Space Agency, AIR LIQUIDE (France) and ORBITAL HYDRAULIC-BREMEN (Germany) have been studying a -183°C freezer to be used on-board the International Space Station for freezing and storing biological samples.

U S Army tactical vehicles are equipped with a wide range of electrical and electronic equipment to support a variety of missions. This equipment typically requires AC input power with varying voltage, power and phasing requirements. Presently, separate inverters with different voltage, power, and phase ratings are necessary to power the equipment, which imposes maintenance and support problems during field deployments. Avionic Instruments Inc. has developed a scalable inverter system that operates from 28V vehicular power and provides outputs that can easily be configured for a variety of load requirements.

This paper presents an application of Bayesian Belief Networks for modeling the uncertainty in aircraft safety diagnostics. Belief networks or influence diagrams represent possible means to efficiently model uncertain causal relationships among components of a system. HUGIN is a software for the construction of knowledge based systems based on Bayesian networks. A HUGIN prototype is dicussed to illustrate how a Bayesian approach could be used to support the decision search routine of aircraft safety inspectors when diagnosing equipment of subsystem malfunctions. The example focuses on diagnostic procedures for assessing aircraft tire condition.