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Abstract : In any human space flight program, safety of the crew is of utmost priority. In case of exigency during atmospheric flight, the crew is safely and quickly rescued from the launch vehicle using Crew escape system. Crew escape system is a crucial part of the Human Space flight vehicle which carries the crew module away from the ascending launch vehicle by firing its rocket motors (Pitch Motor (PM), Low altitude Escape Motor (LEM) and High altitude Escape Motor (HEM)). The structural loads experienced by the crew escape system during the mission abort are severe as the propulsive forces, aerodynamic forces and inertial forces on the vehicle are significantly high. Since the mission abort can occur at anytime during the ascent phase of the launch vehicle, trajectory profiles are generated for abort at every one second interval of ascent flight time considering several combinations of dispersions on various propulsive parameters of abort motors and aero parameters.

A novel method for Single Event Effect (SEE) Radiation Testing using Built-In Self-Test (BIST) feature of indigenously developed Vikram1601 processor is discussed. The novelty is that the usage of BIST avoids need of exhaustive test vectors to ensure test coverage of all the internal registers and physical memory to store them. So processor is the only element vulnerable to radiation damage during testing. The test design was carried out at VSSC, Trivandrum and the testing was carried out at IUAC, Delhi. In the first part, a brief introduction, need and methods of radiation testing of electronics especially SEE of radiation on Silicon based devices, different radiation effects, radiation damage mechanisms and testing methods are described. A brief introduction to Vikram1601 processor, the instruction – TST, used as BIST and testing scheme implementation using TST for studying the SEE is explained.

The test method describes the procedure for determination of the total acid number (TAN) of new and degraded polyol ester and diester-based gas turbine lubricants by the potentiometric titration technique. The method was validated to cover an acidity range of 0.05 to 6.0 mg KOH g-1. The method may also be suitable for the determination of acidities outside of this range and for other classes of lubricants.

In radiography testing, the radioactive elements Iridium 192 (Ir192) and Cobalt 60 (Co60) are employed to detect subsurface and inner flaws. These radioactive components are kept secure within the radiation-protected source camera. Despite the fact that the camera is safe, there is a little quantity of radiation that may harm human body cells. In this present study, it restricts radiation emission by placing a lead sheet over the source camera, which absorbs the produced radiation. The innovative concept involves in this present work is to place a manually operated switch near the radiation source to emit radiation.

This SAE Aerospace Recommended Practice (ARP) is an industrial collaboration with regulatory bodies like the European Aviation Safety Agency (EASA) and the Federal Aviation Administration (FAA) to determine the worst-case credible thermal runaway (TR) condition (energy released and maximum temperature) for the design of an aviation large propulsion battery system to quantitatively verify TR in lieu of battery level RTCA DO-311A testing with protections disabled. The ARP considers the three stages of TR within a cell and defines the two critical temperatures for a specific cell design. These temperatures are key to understanding the layers of monitoring necessary to determine the severity of a TR event. Different trigger methods can be used to quantify the heating characteristics and resultant energy profile releases as a function of time.

This specification establishes requirements for a corrosion-removing compound in the form of a liquid concentrate.

This specification covers requirements for silver deposited on metal parts with a nickel strike between the basis metal and the silver deposit.

This document provides guidance for a means of showing compliance with regulations for protection against lightning direct effects for aircraft of conventional design, as well as for those involving advanced composite structures or other new technologies. This guidance also applies to those aspects of aircraft systems and components not addressed in the regulations covering the protection of electrical/electronic systems (for example, FAR/JAR xx.1316) or fuel systems (for example, xx.954). The guidance provided in this document applies to initial designs as well as modifications.

This document covers metric studs made from a corrosion and heat resistant, age hardenable iron base alloy of the type identified under the Unified Numbering System as UNS S66286. The following specification designations and their properties are covered:

This specification covers the requirements for ion vapor deposited (IVD) aluminum on steel, titanium, and aluminum alloys.

This specification establishes the engineering requirements for producing an acid-type, anodic coating on magnesium alloys and the properties of the coating.

This specification covers a high strength fluorosilicone (FVMQ) elastomer that can be used to manufacture product in the form of sheet, strip, tubing, extrusions, and molded shapes. This specification should not be used for molded rings, compression seals, molded O-ring cord, and molded in place gaskets for aeronautical and aerospace applications.

This guide is intended to promote safe designs, operations and maintenance on aircraft and ground support oxygen systems. This is also a summary of some work by the ASTM G 4 Committee related to oxygen fire investigations and design concerns to reduce the risk of an oxygen fire. There have been many recent technological advances and additional test data is available for evaluating and controlling combustion hazards in oxygen equipment. Standards that use this new information are rapidly evolving. A guide is needed to assist organizations and persons not completely familiar with this process to provide oxygen systems with minimum risks of combustion. This guide does not necessarily address all the detailed issues and provide all data that will be needed. For a complete analysis, supplemental publications need to be consulted. This guide does discuss the basics of oxygen systems fire hazards. The hazard analysis process is discussed and a simple example to explain this process.

This document covers bolts and screws made from a corrosion and heat resistant, precipitation hardenable, iron base alloy of the type identified under the Unified Numbering System as UNS S66286.