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This document sets forth the desired characteristics of an aviation satellite communication (Satcom) system intended for installation in all types of commercial transport and business aircraft. The intent of this document is to provide general and specific guidance on the form factor and pin assignments for the installation of the avionics primarily for airline use. It also describes the desired operational capability of the equipment to provide data and voice communications, as well as additional standards necessary to ensure interchangeability. This Characteristic specifies equipment using Inmarsat satellites operating in L-band. Ku-band and Ka-band equipment is specified in ARINC Characteristic 791.

Protection from the hazards of ionizing radiation in the space environment has been identified as critical to human exploration, and is of the utmost importance both for journeying to and living on other planetary bodies. The major radiation hazards for exploration class missions outside of the Earth's magnetosphere are due to protons from solar particle events and to the highly charged, energetic (HZE) particles constituting galactic cosmic rays. The mean free path for nuclear interactions of HZE particles is comparable to shielding and tissue thicknesses present in human interplanetary exploration, resulting in a significant fraction of nuclear reaction products at depth. The energy deposition of HZE particles, on the microscopic scale of cells, is extremely non-uniform.

It defines how to present Universal Transverse Mercator (UTM) coordinates at various levels of precision. It specifies the use of those coordinates with the grid system defined by the Military Grid Reference System (MGRS). ...Together, the UTM coordinate representation, the MGRS grid, and the specific grid presentation requirements define the USNG.

Exploration of the solar system has captured the imagination of scientists and artists for centuries. The U.S. and other space-faring nations now plan to take the first step by examining the requirements for a human mission to Mars. A three-year journey to Mars will test the limits of our technical and human experience. Maintenance of crew mental and physical health is of utmost importance to mission success. Several critical technologies must be developed to enable healthy and productive crews during Mars missions. The technology development process must begin now, by identifying technology and research requirements, so that the necessary systems are ready when the decision is made to leave Earth and travel to Mars.

In spaceflight operations, the training a crewmember receives on responding to onboard emergencies is of utmost importance. In a high-stress, high-adrenaline situation, crewmembers will have to rely heavily on the training they have received to properly execute the correct procedural response. Working within multiple constraints, NASA instructors have developed and continuously fine-tuned the emergency response training in an effort to make it both as efficient and effective as possible.

In the development of electric actuators, the electric motor to drive the actuator is quite often selected from a set of available motors that have been previously used on other similar programs, or based on legacy experience, or from those that are commercially available seeming to fit for the purpose. Scheduling and budgetary constraints pose a restriction on design and development of a new electric motor specifically for the required application. Generally, these electric motors have minimal weight but deliver maximum output power because of which they tend to heat up rapidly. Such rapid heating can lead to issues such as insulation damage or weakening of the strengths of permanent magnets used in the rotors of permanent magnet induction motors. In such cases, very early in the design phase, it becomes necessary to estimate the temperature rise of the electric motor in a cost effective and rapid way so that the best suitable motor that gives minimal temperature rise is selected.

Small satellites have been around since the dawn of the Space Age. Small, low cost satellites used to be the exclusive domain of scientific and amateur groups. Micro-Satellites fall into the 10–100 Kg category of Small Satellites. They are prone to single point failure and hence utmost care must be taken to design them with low safety factors. This paper gives the preliminary design procedure for a Micro-Satellite with subsystems. Here a Micro-Satellite has been modeled in CATIA and has been studied using ANSYS Finite Element Method codes. Initially the satellite was modeled for the static loads to be carried and after several iterations the optimized model to take dynamic loads with acceptable safety factor was obtained The Finite Element Model results have been validated with experimental results.

Carburetor icing (CI) was the most commonly cited factors in general aviation accident category with 1,019 (34%) accidents. The objective of the study is to measure the CI tendency of selected fuels by the application of factor analysis (FA). All the test fuels were characterized based on chemical and physical properties of the fuels. Gas chromatographic (GC) analysis of the tested fuels were categorized based on hydrocarbon types and basic fuel properties. The study considered sixteen variables for CI assessment, using the selected and calculated fuel properties. Twenty-three aviation fuels from literatures were collected and, using FA, model equations explaining the CI tendency of the aviation fuels were derived, and their respective factor scores were calculated. The model was applied to the 14 fuels in this study, and their respective factor scores were calculated. All the fuels were ranked using the factor score from the best to worst.

Every aircraft produced today contains hundreds of thousands of fastened joints. These joints and the fasteners that connect them are perhaps the most common source of failure in aircraft structure. Therefore, it is imperative that advancements in fastener materials and designs be given the utmost consideration and attention to achieve increased joint performance and integrity. This paper presents the results of development efforts relating to an advanced processing technique and its effect upon selected mechanical properties of certain metallic alloy materials that are deemed appropriate or important for potential fastener applications.

Confining his subject matter strictly to a discussion of the Wright Whirlwind engine and its bearing on the present status of the air-cooled aircraft-engine, the author says that the type of engine specified embodies in its development two distinct forms of cylinder construction, the first having been developed by Charles L. Lawrance and the second by S. D. Heron. The application of these cylinders to the engine under discussion is outlined and the subsequent development is traced. The development of the J-5 type of engine was undertaken in an effort to place the air-cooled engine fully on a par with the water-cooled type as regards fuel consumption. The cylinder is characterized by a hemispherical combustion-chamber employing two valves with axes inclined at 70 deg. The valve-seats are of aluminum-bronze shrunk into the cast-aluminum head. The cylinder-barrel with integral cooling-fins and hold-down flange is screwed and shrunk into the aluminum-head casting.

THREE basic ways in which naval aviation can assist the battle fleet to attain victory are stated, and the aircraft are classified as fighting, observation, torpedo and bombing, and patrol planes. The primary and secondary uses of the types are set forth, and, since their tactical employment controls the features of their design, a brief sketch is given of the tactical considerations of fleet air-work. The development of naval aircraft to date and the trend of future development are then described. As naval fighting planes must be carried on the ships of the fleet and must have the utmost possible performance and service ceiling compatible with low landing-speed, their size and weight have been reduced by the use of air-cooled radial engines and the intelligent employment of light alloys and ingenious detailed construction. The latest development in this class is a single-seater designed around the Wasp 500-hp. engine and equipped with a supercharger.

AS a refinement that permits a smoother external or wetted surface of the airplane, and thus adds to aerodynamic cleanness, flush riveting of the plane's skin is of utmost importance, Mr. Berlin points out. The ultimate object of the research reported, he explains, was to outline the problem of determining and providing requisite tools. No attempt is made in his paper to treat the aerodynamics and strength characteristics of flush riveting. Among the phases of riveting that required careful analysis in the solution of the problem noted especially by Mr. Berlin are appearance, strength, processing methods, economics of production and sources for equipment and tools. Time studies were employed extensively, and close contact with the production departments was maintained in the work.

In this work, a Carbon Fibre Reinforced Polymer (CFRP) Wheel Centre (WC) is designed targeting key parameters such as reduced un-sprung mass and lower rotational inertia in vehicle dynamics. A Keizer Aluminium Wheel Centre was used by the team previously and it weighed around 1.8 Kg. Designing of CFRP Wheel Centre was based on previously used Keizer Aluminium wheel centre considering the design constraints such as distance between hub and wheel assembly. This was done to ensure the same trackwidth within the Formula Student rules. Initially, the Finite Element Analysis (FEA) was carried out for the Keizer Aluminium wheel centre and the results were analysed. For the same design CFRP material was used and the result was found out to be promising with a wheel centre weight of 1.3 Kg. Further to improve the performance and weight reduction, FEA was done to design a 38 layered CFRP wheel centre giving utmost priority to ease of manufacturability and safe design.

A well designed landing gear and a proper integration is of utmost importance for the success of any aircraft design. This should never be neglected but often is, especially in the conceptual design stage. This paper reflects the author’ s own experience in landing gear design on the Saab Gripen aircraft as well as experience gained on aircraft conceptual designs of later dates. The aim of the paper is to underline the importance of spending more time on landing gear design and integration in conceptual design. The paper reflects the importance of proper interaction between landing gear design and other disciplines and above all underlines the fact that landing gear design should be treated as an equally important design parameter, just as any other, in the final choice of aircraft configuration.

New trends in aircraft design suggest that there may be a mission advantage to placing the aircraft engine in backwards for applications in Unmanned Combat Air Vehicles (UCAV’s). These aircraft use stealth as their primary defense. Stealth is, therefore, of utmost importance leaving aerodynamics to take a lower priority in the design process. The combination of a flying wing, planform shape, airfoil and stability and control of these aircraft limit the maximum lift coefficient of the vehicle to a relatively low value. Increasing the maximum lift coefficient can be achieved by use of thrust vectoring forward of the center of gravity. This suggests an internal layout that places the engine flow opposite to that of the free stream. This design is currently being developed in an Embry-Riddle Aeronautical University undergraduate design course.

THE impression that recent aircraft experience should have taught engineers how to revolutionize automobile construction and performance, is not warranted by the facts involved. Aircraft and automobiles both embody powerplants, transmission mechanisms, running gear, bodies and controls, but their functions are entirely different. The controls of an airplane, except in work on the ground, act upon a gas, whereas with an automobile the resistant medium is a relatively solid surface. Similarly, the prime function of the fuselage is strength, weight considerations resulting in paying scant attention to comfort and convenience, which are the first requirements of an automobile body. Aircraft running-gear is designed for landing on special fields, and is not in use the major portion of the time. The running-gear is the backbone of an automobile, in use continuously for support, propulsion and steering; hence its utterly different design.

While unmanned aircraft system (UAS) operations and UAS Traffic Management (UTM) are often touted as “safety critical”, the systems and technologies are not being held to the same standards as traditional aviation, with its long pedigree of safety. ...At the architecture level, the federated approach to UTM has led to a void in the Systems Engineering process. Nobody “owns” the entire system and therefore nobody owns the Systems Engineering process where many safety related design decisions are traditionally made. ...Without certification to design assurance standards, the UTM industry will instead need to look towards higher level performance-based standards. Safety levels for the ecosystem will be encapsulated by risk ratios and target level of safety metrics.

What system Designers Should Know About MOSA Standards Microtube Technology A Catalyst for Next-Gen Aerospace Thermal Control Space Industry Test Challenges Advancing Metrology at Mach Speed Drone Mounted Inspection Breaks Barriers for F-35 RF Technology Helps Connect Avionics Systems Using Open-Cavity Plastic Packages in Avionics Applications Electronic Prognostics - A Case Study Using Global Positioning System (GPS) Prognostic health management (PHM) of electronic systems presents challenges traditionally viewed as either insurmountable or not worth the cost of pursuit, but recent changes in weapons platform acquisition and support requirements has spurred renewed interest in electronics PHM, revealing possible applications, accessible data sources, and previously unexplored predictive techniques.

Large-scale aerostructures are commonly constructed using multiple layers of stacked material which are fastened together using mechanical methods. Ensuring the interface gaps between these materials are kept within engineering tolerances is of utmost importance to the structural integrity of the aircraft over its service life. Manual, right angle feeler gauges are the traditional method for measurement of interface gaps, but this method is tedious and mechanic dependent. A portable hand tool utilizing low-coherence interferometry has been developed to address these issues. The tool uses a right-angle probe tip which is inserted into a previously drilled hole and driven through the depth of the material. A line scan of data is collected and analyzed for the presence of interface gaps. To measure the consistency of the gap around the circumference of the hole, the tool is rotated by the operator and additional scans are collected.

Automatic Target Recognition provides an inside view of the automatic target recognition (ATR) domain from the perspective of an engineer working in the field for 40 years. The algorithm descriptions and testing procedures covered in the book are appropriate for addressing military problems and unique aspects and considerations in the design, testing, and fielding of ATR systems. These considerations need to be understood by ATR engineers working in the defense industry as well as by their government customers. The final chapter discusses the future of ATR and provides a type of Turing test for determining if an ATR system is truly smart (neuromorphic or brain-like). The Appendix provides difficult-to-find resources available to the ATR engineer.