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Hypersonic flight vehicles have potential applications in strategic defence, space missions, and future civilian high-speed transportation systems. ...Scramjet-powered air-breathing hypersonic vehicles experience extreme heat loads induced by combustion, shock waves and viscous heat dissipation.

Scramjet-based hypersonic airbreathers are needed for next-generation defense and space applications. Two scramjet configurations, namely, rectangular and axisymmetric, are primarily studied in the literature.

Abstract At hypersonic speed, severe aerodynamic heating is observed, and temperatures are too high to cool by radiation cooling; active cooling such as ablative cooling is helpful in this situation. ...A Computational Fluid Dynamics (CFD) simulation of a two-dimensional (2D) lifting body against thermally perfect air in a hypersonic region (Mach number, M > 5) is carried out for M = 5–9 to obtain a heat-transfer-minimized sweepback angle (ΛHT-min), at which heat transfer to the vehicle is minimum.

Abstract At supersonic aircraft speeds, aerodynamically heated surfaces, e.g., nose, wing leading edges, are infrared (IR) signature sources from the tactically crucial frontal aspect. This study numerically predicts and then illustrates the minimization of IR contrast between the nose and background sky radiance by the emissivity optimization (εw,opt) technique, which has the least performance penalties. The IR contrast between the aircraft nose and its replaced background in 1.9-2.9 μm short-wave IR (SW-IR), 3-5 μm medium-wave IR (MW-IR), and 8-12 μm long-wave IR (LW-IR) bands are obtained. The IR contrast especially in LW-IR (i) increases with flight Mach number (M ∞) for a given flight altitude (H) and εw (ii) decreases with increasing H for a given M ∞ and εw. The εw,opt for a flight altitude of 5 km is found to decrease from 0.99 at M ∞ = 0.001 (low subsonic) in all three bands to 2 × 10−4 in MW-IR and 0.0213 in LW-IR bands at M ∞ = 3 (high supersonic).

This SAE Aerospace Information Report (AIR) covers the field of civilian, commercial and military airplanes and helicopters. This summary of tail bumper design approaches may be used by design personnel as a reference and guide for future airplanes and helicopters that require tail bumpers. Those described herein will consist of simple rub strips, structural loops with a wear surface for runway contact, retractable installations with replaceable shock absorbers and wear surfaces and complicated retractable tail landing gears with shock strut, wheels and tires. The information will be presented as a general description of the installation, its components and their functions.

This section presents the basic equations for computing ice protection requirements for nontransparent and transparent surfaces and for fog and frost protection of windshields. Simplified graphical presentations suitable for preliminary design and a description of various types of ice, fog, frost, and rain protection systems are also presented.

This SAE Aerospace Information Report (AIR) covers the field of civilian, commercial and military airplanes and helicopters. This summary of tail bumper design approaches may be used by design personnel as a reference and guide for future airplanes and helicopters that require tail bumpers. Those described herein will consist of simple rub strips, structural loops with a wear surface for runway contact, retractable installations with replaceable shock absorbers and wear surfaces and complicated retractable tail landing gears with shock strut, wheels and tires. The information will be presented as a general description of the installation, its components and their functions.

This SAE Aerospace Recommended Practice (ARP) provides guidance for substantiating the airworthiness of aircraft engine components. Generally these components are associated with the engine control system, the system or systems that allow the engine to provide thrust or power as demanded by the pilot of the aircraft while also ensuring the engine operates within acceptable operating limits. But these components may also include hardware and systems associated with engine lubrication, engine or aircraft hydraulic or electrical systems, aircraft environmental control systems, thrust reverser control, or similar aircraft or engine propulsion system functions. This paper develops the concept of using a 26 item matrix of environmental conditions for evaluating aircraft engine component airworthiness. This approach is compatible with current practices used in the industry and has been accepted by engine certification authorities as part of engine certification programs.

This section presents methods and examples of computing the steady-state heating and cooling loads of aircraft compartments. In a steady-state process the flows of heat throughout the system are stabilized and thus do not change with time. In an aircraft compartment, several elements compose the steady-state air conditioning load.

Bye Aerospace is looking at OXIS Energy Ltd.’s lithium-sulfur (Li-S) battery cell technology to power its future aircraft and air-taxi or “urban air mobility” (UAM) designs. The companies are launching the initial phase of an advanced, high-voltage, lightweight Li-S battery pack development program for aerospace applications.

Two members of DCS Corp – Mark Wilkins and Finley Barfield – won the highly distinguished Robert J. Collier Trophy by the National Aeronautic Association for their work on the Air Force Research Laboratory (AFRL) Automatic Ground Collision Avoidance System (Auto-GCAS) team.

Originally published in 1995, now updated and expanded with new specifications, this seminal work focuses on the development of Allied aircraft engines that helped turn the tide of World War II.

Lockheed Martin's Auto-GCAS uses terrain mapping, geolocation, and automation to detect and avoid potential ground collisions in case of pilot spatial disorientation. The technology was initially fielded on the F-16 Fighting Falcon, but will now save an estimated 26 crashes over the course of F-35 service life.

Under the contract, Raytheon will design, develop, produce, and sustain active electronically scanned array (AESA) radar systems for the U.S. Air Force’s entire B-52 long-range strategic bomber fleet, keeping the nearly 65-year-old aircraft mission ready through 2050 and beyond.

The Oshkosh, Wisconsin-based kit aircraft manufacturer is developing a two-seat variant of its SubSonex JSX-2 personal jet. The SubSonex JSX-2T is designed to be the lowest cost jet trainer ever built and the company hopes that it will lead to further interest in its single-seat JSX-2.

The Boeing Company is kicking off a new round of flight-testing to research approximately 50 technology projects related to safety, environmental sustainability, and passenger experience. More than a dozen partners are participating in the 2019 program.

The test was conducted to better understand the dynamic forces on an aircraft and its passengers during a crash landing. Findings form the event will support a new FAA performance-based rule that will simplify aircraft certification by eliminating or minimizing the use of special conditions.

The fluid flow treated in this section is isothermal, subsonic, and incompressible. The effects of heat addition, work on the fluid, variation in sonic velocity, and changes in elevation are neglected. An incompressible fluid is one in which a change in pressure causes no resulting change in fluid density. The assumption that liquids are incompressible introduces no appreciable error in calculations, but the assumption that a gas is incompressible introduces an error of a magnitude that is dependent on the fluid velocity and on the loss coefficient of the particular duct section or piece of equipment. Fig. 1A-1 shows the error in pressure drop resulting from assuming that air is incompressible. With reasonably small loss coefficients and the accuracy that is usually required in most calculations, compressible fluids may be treated as incompressible for velocities less than Mach 0.2.

SAE International has published a new recommended practice for assessing the amount of nonvolatile particulate matter (nvPM) that exits aircraft engine exhaust nozzles – ARP6481: Procedure for the Calculation of Non-Volatile Particulate Matter Sampling and Measurement System Losses and System Loss Correction Factors