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The Aerospace Technical Paper Collection is a family of technical papers as either an annual subscription (current papers, archived papers, or both) or a perpetual collection (1906-1997). This collection is perfect for aerospace engineers, managers, or educators who need access to the most current content covering today's most relevent topics. Please contact one of our sales representatives to learn more and start your subscription today! SAE Sales Team customersales@sae.org 1-888-875-3976 (U.S. and Canada) 1-724-772-4086 (Outside the U.S.)

This talk will present an overview of the newly published DO-326/ED-202 "Airworthiness Security Process Specification". Presenter Daniel P. Johnson, Honeywell

The presentation provides an overview about the activities of Eurocae Working Group 72 (WG-72) starting with a brief synopsis of the context which suggested why such a committee should be established in 2006. It then goes into further detail about the drivers for the work of the committee, which call for the products to be delivered. It addresses some of the challenges with respect to its users. It points out that one of the lessons the committee learned was importance of the focus on the users, such that the products provide their maximum utility. Hence, the users should better be among the participants to achieve this objective. Other industries have dealt with the subject of Information System (or Cyber-Physical) Security long before this industry was forced to consider it. Consequently there are many industry standards and national or international norms, which may help to develop what is deemed needed for Civil Aviation.

This presentation provides a overview of validating Time Triggered Ethernet (TTE) for use as the network to interconnect the avionics for manned Space Vehicle. The next manned Space Vehicle will use Time Triggered-Gigabit Ethernet (TT-GbE) leveraged from commercial development of TTE critical Intellectual Property. There are several validation considerations of either separating TTE segments or adding new TTE segments onto the network caused by the different phases of a manned space vehicle from pre-launch to re-entry. Considerable amount of validation testing has been successfully performed on TT-GbE/TTE. Presenter Victor Revelle, Honeywell International Inc.

Listen in as Dr. Ravi Rajamani discusses his new book, the history of electric flight, and electric propulsion. Learn more at books.sae.org/t-135.

With the increased demand for high volume, cost-effective, fiber-reinforced thermoplastic parts, the lack of high throughput systems has become more pronounced. Thermoforming as a method to generate complex shapes from a flat preform is dependable and fast. In order to use readily available, standard unidirectional impregnated thermoplastic tape in this process, a flat perform must be created prior to the thermoforming step. Formerly, creating the preform by hand layup was a time consuming and therefore costly, step. Fiberforge�?s patented RELAY� technology overcomes the challenges of handling thermoplastic prepreg tape and provides a solution through the automated creation of a flat preform, referred to as a Tailored Blank?. Producing a part for thermoforming with accurate ply orientation and scrap minimization is now as simple as loading a material spool followed by a pressing a start button. Presenter Christina McClard, Fiberforge

Abstract This study discusses the experimental investigation on WEDM of combustor material (i.e., nimonic 263). Experimentation has been executed by varying pulse-on time (Ton), pulse-off time (Toff), peak current (Ip), and spark gap voltage (Sv). Material removal rate (MRR), surface roughness (SR), and wire wear rate (WWR) are employed as process performance characteristics. Experiments are designed as per the box-Behnken design technique. Parametric optimization has also been performed using response surface methodology. Besides this, field-emission scanning electron microscope (FE-SEM) and an optical microscope are utilized to characterize WEDMed and worn-out wire surfaces. It is observed that both surfaces contain micro-cracks, craters, spherical droplets, and a lump of debris. Furthermore, the mechanism of recast layer formation has been critically evaluated to apprehend a better understanding of the technique. The key features of the experimental procedure are also highlighted.

Abstract While the design of nozzles for diatomic gases is very well established and covered by published works, the case of a diatomic gas dissociating to monatomic along a nozzle is a novel subject that needs a proper mathematical description. These novel studies are relevant to the definition of nozzles for gas-core Nuclear Thermal Rockets (NTR) that are receiving increased attention for the potential advantages they may deliver versus current generation rockets. The article thus reviews the design of the nozzles of gas-core NTR that use hydrogen as the propellant. Propellant temperatures are expected to reach 9,000-15,000 K. Above 1500 K, hydrogen begins to dissociate at low pressures, and around 3000 K dissociation also occurs at high pressures. At a given temperature, the lower the gas pressure the more molecules dissociate, and H2 → H + H. The properties of the gas are a function of the mass fractions of diatomic and monatomic hydrogen x H2 and x H = 1 − x H2.

Abstract It is reasonable to use a two-phase heat transfer loop (TPL) in a thermal control system (TCS) of spacecraft with large heat dissipation. One of the key elements of TPL is a heat-controlled accumulator (HCA). The HCA represents a volume which is filled with vapor and liquid of a single working fluid without bellows. The pressure in a HCA is controlled by the heater. The heat and mass transfer processes in the HCA can proceed with a significant nonequilibrium. This has implications on the regulation of TPL. This article presents a mathematical model of nonequilibrium heat and mass transfer processes in an HCA for microgravity conditions. The model uses the equations of mass and energy conservation separately for the vapor and liquid phases. Interfacial heat and mass transfer is also taken into account. It proposes to use the convective component k for the level of nonequilibrium evaluation.

The CDIF Family of Standards is primarily designed to be used as a description of a mechanism for transferring information between CASE tools. It facilitates a successful transfer when the authors of the importing and exporting tools have nothing in common except an agreement to conform to CDIF. The language that is defined for the Transfer Format also has applicability as a general language for Import/Export from repositories. The CDIF Integrated Meta-model defined for CASE also has applicability as the basis of standard definitions for use in repositories. The standards that form the complete family of CDIF Standards are documented in EIA/IS-106 CDIF - CASE Data Interchange Format - Overview. These standards cover the overall framework, the transfer format and the CDIF Integrated Meta-model. The diagram in Figure 1 depicts the various standards that comprise the CDIF Family of Standards. The shaded box depicts this Standard and its position in the CDIF Family of Standards.

This recommended practice provides users with raw GNSS measurements to facilitate positioning, navigation, or timing solutions.

This standard provides recommended practices to significantly enhance the ability of PNT users to defend against a range of interference, jamming, and spoofing phenomena.

This standard establishes the inertial and health monitoring data interface requirements for inertial measurement units used for military and aerospace vehicle applications.

This standard establishes the SAE2020 compliant inertial data interface requirements for simulator integration with inertial navigation systems used for military and aerospace vehicle applications.

This standard defines a test plan to verify an inertial measurement unit interface meets the requirements of SAE2020.

There are numerous GNSS user equipment interface standards in use that provide some form of timing and/or positioning information. This document incorporates their essential content into a uniform array that will enable seamless interoperation with eLoran.

There are numerous GNSS user equipment interface standards in use that provide some form of timing and/or positioning information. This document incorporates their essential content into a uniform array that will enable seamless interoperation with eLoran.

This standard provides guidelines for resilient GNSS receivers.

This standard defines how a resilient GNSS receiver provides enough information for an alternative PNT source to be selected when the GNSS receiver does not meet the required levels of accuracy, availability, integrity, or continuity even when the GNSS signals are subject to interference