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This paper presents a Military Space Plane design concept. While the current military space plane activity is focused on rocket-powered concepts, the concept presented here is powered by a rocket-based combined cycle engine that uses both rocket and air-breathing engine cycles. The design concept is the reference SSTO design concept used in the NASA HRST ANSER study. The reference concept is a derivative of the NASA air-breathing Access to Space study SSTO design concept. The Access to Space air-breathing vehicle's combined cycle engine was replaced by the Aerojet rocket-based combined cycle engine. The orbital performance capability of the reference design concept is presented for 100 n mi., polar, and 225 n mi., 51 deg. orbits. The sensitivity of GTOW to payload and margin is also presented.

The primary purpose of a Propellant Transfer Unit (PTU) is to temperature-condition and weigh a specific amount of propellant, and transfer if to a vehicle propellant tank. A secondary purpose of a PTU may be to drain propellant from the vehicle tank and return it to the transfer unit when required. The transfer unit may also be used for flushing the vehicle fill lines and transfer unit with appropriate flushing fluids, followed with nitrogen for the purpose of drying the lines and weigh tank. The transfer unit may include provisions for helium purging of the propellant transfer tank and lines, ad supplying a blanket of helium pressure to the transfer tank. Each PTU consists of a piping system with appropriate propellant and pneumatic valves, regulators, relief valves, filters and a propellant pump. Various components such as a scrubber, bubbler, propellant cooler (heat exchanger), propellant weigh tank, weigh scale and a chiller may make up the balance of the assembly.

This SAE Aerospace Standard (AS) defines the requirements for air cycle air conditioning systems used on military air vehicles for cooling, heating, ventilation, and moisture and contamination control. General recommendations for an air conditioning system, which may include an air cycle system as a cooling source, are included in MIL-E-18927E and JSSG-2009. Air cycle air conditioning systems include those components which condition high temperature and high pressure air for delivery to occupied and equipment compartments and to electrical and electronic equipment. This document is applicable to open and closed loop air cycle systems. Definitions are contained in Section 5 of this document.

This document is divided into five parts. The first part deals with flotation analysis features and definitions to acquaint the engineer with elements common to the various methods and the meanings of the terms used. The second part identifies and describes current flotation analysis methods. Due to the close relationship between flotation analysis and runway design, methods for the latter are also included in this document. As runway design criteria are occasionally used for flotation evaluation, including some for runways built to now obsolete criteria, a listing of the majority of these criteria constitutes the third part. The fourth part of this document tabulates the most relevant documents, categorizing them for commercial and civil versus military usage, by military service to be satisfied, and by type of pavement. This document concludes with brief elaborations of some concepts for broadening the analyst’s understanding of the subject.

Aluminum alloys are employed in agricultural equipment, aerospace sectors, medical instruments, machinery, automobiles, etc. due to their physical and mechanical characteristics. The geometrical shape and size of the parts are modified in turning operation by using a single-point cutting tool. A356 aluminum alloy is widely used in various engineering sectors, hence there is a necessity to produce A-356 components with quality. The inappropriate cutting parameters used in turning operation entail high production costs and reduce tool life. Box–Behnken design (BBD) based on response surface methodology (RSM) was used to design the experiments such that the experiment trials were conducted by varying cutting parameters like N-spindle speed (rpm), f-feed rate (mm/rev), and d-depth of cut (mm). The multi-objective responses, such as surface roughness (SR) and metal removal rate (MRR) were analyzed with the desirability method.

After manufacture, every military vehicle experiences a unique history of dynamic loads, depending on loads carried, missions completed, etc. Damage accumulates in vehicle structures and components accordingly, leading eventually to failures that can be difficult to anticipate, and to unpredictable consequences for mission objectives. The advent of simulation-based fatigue life prediction tools opens a path to Digital Twin based solutions for tracking damage, and for gaining control over vehicle reliability. An incremental damage updating feature has now been implemented in the Endurica CL fatigue solver with the aim of supporting such applications for elastomer components. The incremental updating feature is demonstrated via the example of a simple transmission mount component. The damage state of the mount is computed as it progresses towards failure under a series of typical loading histories.

Fuel tank is considered as safety component in the vehicle, and it has to be tested to meet the safety requirements as per AIS 095. Earlier, fuel tanks were manufactured by using Hot dipped cold rolled steel material and the weld zones are applied with Anti-corrosive coating. Few fuel tanks were reported with Corrosion problems. The root cause analysis was carried out considering the raw material, manufacturing process, transpiration, storage and usage. As an improvement, the new fuel tank is designed to eliminate the limitations of the existing fuel tank. 3D modeling was done to check space and mounting requirement in the layout and used for volume calculations. FE analysis was performed to check structural stability. Emphasis given on Interchange-ability to cater the new fuel tanks in place of old as spares requirement. The fuel tank has developed with Alumina steel material.

The limitations of commonly used materials such as steel in withstanding high temperatures led to exploring alternative alloys. For instance, Inconel 825 is a nickel-based alloy known for its exceptional corrosion resistance. Thus, the Inconel 825 is used in various applications, including aerospace, marine propulsion, and missiles. Though it has many advantages, machining this alloy at high temperatures could be challenging due to its inadequate heat conductivity, increased strain hardening propensity, and extreme dynamic shear strength. The resultant hardened chips generated during high-speed machining exhibit elevated temperatures, leading to tool wear and surface damage, extending into the subsurface. This work investigated the influence of varying process settings on the machinability of Inconel 825 metal, using both uncoated and coated tools.

Ferrous metals contain iron and are prized for their tensile strength and durability. Most are magnetic and contain a high carbon content which generally makes them, with the exception of wrought iron and stainless steel, vulnerable to rust. The following seven eLearning courses are included in the Ferrous Materials Bundle: Steel and Cast Iron. Each course is approximately one-hour in duration. Modules include: Introduction to Physical Properties, Introduction to Mechanical Properties, Introduction to Metals, Hardness Testing, Ferrous Metals, Classification of Steel, Essentials of Heat Treatment of Steel.

Fatigue is a structural failure mode that must be recognized and understood to develop products that meet life cycle durability requirements. In the age of lightweighting, fatigue strength is an important vehicle design requirement as engineers struggle to meet stringent weight constraints without adversely impacting durability. This technical concept course introduces the fatigue failure mode and analysis methods. It explains the physics of material fatigue, including damage accumulation that may progress to product failure over time, and it provides the needed foundation to develop effective fatigue prediction capabilities.

Abstract Autonomy has the potential to make the most radical impact by significantly reducing the number of soldiers in harm’s way and changing the military paradigm. Benefits of autonomy to improve the Army’s mission capabilities and the rapid evolution of military systems exerts pressure to develop these systems quickly. Since the associated technological development is highly fast paced and stochastic, approaches that develop systems for stochastic future scenarios are required. In this article we present a vision for the autonomous high-mobility military systems for that future. We discuss the ramifications of autonomy in five areas: (1) fleet organization, (2) physical attributes of high-mobility military systems, (3) individual behaviors of autonomous assets, (4) interactions between humans and autonomous systems, and (5) operation and teaming strategies. We present the future vision, implications, requirements, and technological challenges for each of the five areas.

Author Francis Bradford, a former Hall-Scott engineer, provides valuable resources and insight not available to any other Hall-Scott researcher. Well-illustrated with numerous photos, drawings, and memos, this fascinating book will be of interest to history buffs in the areas of aviation, rail, marine, trucks, buses, fire equipment, and industrial engines, and to World War and military historians.

Metals and alloys have different melting ranges depending on their chemistry. High temperature metals are much harder at room temperature, have exceptionally high melting points (usually above 2000 degree Celsius), and are resistant to wear, corrosion and deformation. The following five eLearning courses are included in the High Temperature Materials bundle.  Each course is approximately one-hour in duration. See Topics/Outline for additional details.

In the early days, there were significant limitations to the build size of laser powder bed fusion (L-PBF) additive manufacturing (AM) machines. However, machine builders have addressed that drawback by introducing larger L-PBF machines with expansive build volumes. As these machines grow, their size capability approaches that of directed energy deposition (DED) machines. Concurrently, DED machines have gained additional axes of motion which enable increasingly complex part geometries—resulting in near-overlap in capabilities at the large end of the L-PBF build size. Additionally, competing technologies, such as binder jet AM and metal material extrusion, have also increased in capability, albeit with different starting points. As a result, the lines of demarcation between different processes are becoming blurred.

This course is verified by Probitas Authentication as meeting the AS9104/3A requirements for continuing Professional Development. Why is a design for manufacturing, assembly and automation so important? This introductory course on airframe engineering will cover the importance of design for manufacturing, assembly and automation in aerospace. It will review what the key drivers are for a “good” design and some of the key points for manufacturing and assembly of aircraft components. It will look at how an engineer can combine traditional technologies with new, cutting-edge technologies, to determine the best scenario for success.

The following six eLearning courses are included in the Introduction to Materials bundle.  Each course is approximately one-hour in duration. See Topics/Outline for additional details. Introduction to Physical Properties  This course provides an an overview of manufacturing materials and their physical properties, including thermal, electrical, and magnetic properties and introduces volumetric characteristics, such as mass, weight, and density.

Facial recognition software (FRS) is a form of biometric security that detects a face, analyzes it, converts it to data, and then matches it with images in a database. This technology is currently being used in vehicles for safety and convenience features, such as detecting driver fatigue, ensuring ride share drivers are wearing a face covering, or unlocking the vehicle. Public transportation hubs can also use FRS to identify missing persons, intercept domestic terrorism, deter theft, and achieve other security initiatives. However, biometric data is sensitive and there are numerous remaining questions about how to implement and regulate FRS in a way that maximizes its safety and security potential while simultaneously ensuring individual’s right to privacy, data security, and technology-based equality.

Almost 75% of all elements are metals. Metals can be classified as either ferrous or non-ferrous and generally conduct electricity and heat well. Most metals are malleable and ductile and are, in general, heavier than other elemental substances. The following six eLearning courses are included in the Materials bundle. Each course is approximately one-hour in duration. See topics/outline for additional details. Introduction to Metals, Ferrous Metals, Nonferrous Metals, Classification of Steel, Essentials of Heat Treatment of Steel Exotic Alloys

The advancement of both sensory and unmanned technology, combined with increased utilization of autonomous platforms in complex teaming scenarios, has created a need for practical design space exploration tools to aid in the synthesis of effective System-of-Systems (SoS). The presented work describes a modular, flexible, and extensible framework, referred to herein as the Technologies and Teaming Evaluation (TATE) framework, for straightforward identification of high-quality SoS, which may include both manned and autonomous elements, through quantitative evaluation of system-level and SoS-level attributes against a set of user-defined reference tasks.

The first issue of the National Automotive Center Technical Review, this report is a collection of technical papers developed by leading NAC engineers, scientists and industry partners to demonstrate the ongoing work to improve automotive performance, safety and endurance while reducing the cost of both military and civilian vehicles. Published by National Automotive Center. Distributed by SAE.