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In recent years there has been increasing interest in quantifying the emissions from aircraft in order to generate inventories of emissions for climate models, technology and scenario studies, and inventories of emissions for airline fleets typically presented in environmental reports. The preferred method for calculating aircraft engine emissions of NOx, HC, and CO is the proprietary “P3T3” method. This method relies on proprietary airplane and engine performance models along with proprietary engine emissions characterizations. In response and in order to provide a transparent method for calculating aircraft engine emissions non proprietary fuel flow based methods 1,2,3 have been developed. This paper presents derivation, updates, and clarifications of the fuel flow method methodology known as “Fuel Flow Method 2”.

THIS STANDARD ESTABLISHES THE DIMENSIONAL AND VISUAL QUALITY REQUIREMENTS, LOT REQUIREMENTS, AND PACKAGING AND LABELING REQUIREMENTS FOR D-RINGS MOLDED FROM MIL-P-25732 ACRYLONITRILE BUTADIENE (NBR) RUBBER. IT SHALL BE USED FOR PROCUREMENT PURPOSES.

During several ISS missions, there were false alarms at both US and Russian smoke detectors. High local airborne particulate concentrations and interior deposits are considered the causes for such anomalies. Alternatives are proposed to replace or complement these faulty smoke detectors. The entrained zeolite particles may play a role in causing problems with check valves and air save pumps in CDRA and Vozdukh. Another incidence has been the dispersion of particulates out of Metox regeneration oven. Particulate matters with aerodynamic diameter of 15 microns and above, which normally settle down on earth, stay airborne under micro-gravity and thereby cause the above-mentioned nuisances. The motion of such a particle along a gas stream with an initial velocity can be expressed by theoretical equations. Stokes' Law leads to the descriptions of inertial precipitation of aerosols that are important in solving the issues.

The paper summarizes the experience gained on the ISS water management system during the missions of ISS-1 through ISS-16 (since November 2 2000, through December 31, 2007). The water supply sources and structure, consumption and supply balance at various phases of space station operation are reviewed. The performance data of the system for water recovery from humidity condensate SRV-K and urine feed and pretreatment system SPK-U in the Russian orbital segment are presented. The key role of water recovery on a board the ISS and the need to supplement the station's water supply hardware with a system for water reclamation from urine, water from a carbon dioxide reduction system and hygiene water is shown.

A zirconia electroysis cell is an all-solid state (mainly ceramic) device consisting of two electrodes separated by a dense zirconia electrolyte. The cell electrochemically reduces carbon dioxide to oxygen and carbon monoxide at elevated temperatures (800 to 1000°C). The zirconia electrolysis cell provides a simple, lightweight, low-volume system for Mars In-Situ Resource Utilization (ISRU) applications. This paper describes the fabrication process and discusses the electrochemical performance and other properties of zirconia electrolysis cells made by the tape calendering method. Electrolytes produced by this method are very thin (micrometer-thick); the thin electrolyte reduces ohmic losses in the cell, permitting efficient operation at temperatures of 800°C or below.

This specification covers a zinc alloy in the form of die castings.

The commercial aviation currently accounts for roughly 2.5 % of the global CO2 emissions and around 3.5% of world warming emissions, taking into account non CO2 effects on the climate. Its has grown faster in recent decades than the other transport modes (road, rail or shipping), with an average rate of 2.3%/year from 1990 to 2019, prior to the pandemic. Moreover, its share of Greenhouse (GHG) emissions is supposed to grow, with the increasing demand scenario of air trips worldwide. This scenario might threaten the decarbonization targets assumed by the aviation industry, in line with the world efforts to minimize the climate effects caused by the carbon emissions. In this context, hydrogen is set as a promising alternative to the traditional jet fuel, due to its zero carbon emissions.

(From Standards Proposal No. 2358, formulated under the cognizance of the EIA Quality and Reliability Engineering (QRE) Committee.)

Conventional attribute sampling plans based upon nonzero acceptance numbers are no longer desirable. In addition, emphasis is now placed on the quality level that is received by the customer. This relates directly to the Lot Tolerance Percent Defective (LTPD) value or the Limiting Quality Protection of MIL-STD-105. Measuring quality levels in percent nonconforming, although not incorrect, has been replaced with quality levels measured in parts per million (PPM). As a result, this standard addresses the need for sampling plans that can augment MIL-STD-105, are based upon a zero acceptance number, and address quality (nonconformance) levels in the parts per million range. This document does not address minor nonconformances, which are defined as nonconformances that are not likely to reduce materially the usability of the unit of product for its intended purpose.

This specification covers a zinc alloy in the form of die castings.

This paper describes the ZENITH Nano-Satellite cum planetary atmospheric entry vehicle, called CanSat, the first Nano-Satellite project that has been developed by Delhi Technological University (Formerly Delhi College of Engineering), India. The satellite will function for monitoring the concentrations of various gases in the atmosphere. For this, the satellite consists of arduino microcontroller interfaced with the various Micro-electromechanical system (MEMS) gas sensors for measuring the concentrations of various gases such as carbon dioxide, carbon monoxide, methane, nitrous oxides, ozone, etc. The data obtained from the CanSat will be transmitted to the ground station where all the data will be stored and also the locations will be stored using GPS sensor. The academic goal of this project is to recruit students to the field of space science and technology.

The YF-23A Advanced Tactical prototype Fighter was a revolutionary statically unstable, twin engine aircraft that cruised at supersonic speeds without afterburner and was designed to out maneuver opponents at subsonic and supersonic speeds. Combining these capabilities into a chosen aircraft configuration demanded a flight control hydraulic system of unprecedented power and performance. Increased system reliability, and reduced maintenance also presented a challenging system design. The YF-23A's unique flight and maneuvering envelope required high surface rates and large actuator excursions at low flight speeds, as well as power to generate increased hinge moments at supersonic speeds. To achieve these specifications, Northrop developed a hydraulic system that utilized flow conservation and prioritization techniques. The hydraulic system configuration was maintained by using hydrologic, as well as electronic control.

THE X-ray spectrum readily adapts itself to problems in chemical analysis and crystal formation. It is effective on very minute particles which otherwise cannot be segregated. A permanent record is made, and the specimens may be used over and over again, as the X-ray is non-destructive. As a means of inspection, X-ray clearly shows the interior of objects such as weldings castings, forgings, cold-worked metals, and so on. Inhomogeneities that are very slight in width and a fraction of one per cent in thickness are seen easily on a radiograph. Defects thus found may be eliminated summarily by checking various steps in production.

X-ray is an indispensable aid in locating and determining the extent of incipient failures in structure which is inaccessible by position or covered by multiple layers of metal. It is also the most feasible method for checking oil coolers for contamination; bonded honeycomb panels for water; fuel lines for erosion; and with a 360 deg emission tube, fuselage frames for structural integrity without removing the interior upholstery and panels from the passenger compartment or cargo compartments.

Over the past two decades, various models of “worst case” solar energetic particle event (SPE) spectra have been proposed in order to place an upper bound on the likely doses to critical body organs of astronauts on missions outside Earth’s geomagnetic field. In this work, direct comparisons of organ dose estimates for various models of “worst case” SPE spectra are made by using the same transport code (BRYNTRN) and the same human geometry model (Computerized Anatomical Man). The calculations are made assuming nominal thicknesses of spacecraft aluminum shielding. Discussions of possible acute exposure responses from these exposures are presented.

The first flight of a delta wing aircraft took place in the United States at the Muroc AFB Flight Test Center on 18 September 1948. The aircraft, Convair No. 7002, Air Force S/N 46-682 and designated the XF-92A was piloted by Convair's Manager of Flight Research, E.D. “Sam” Shannon. The author witnessed this historic flight as a Flight Test Engineer on the project. Studies and wind tunnel tests for a supersonic interceptor were conducted at the Vultee Division of Consolidated Vultee Aircraft Corporation (Convair) in 1945. These studies led to the selection of the 60° delta wing plan form. This paper reviews the major differences between the thin wing XF-92A and the thick wing DM-1 glider (never flown) designed by Alexander M. Lippisch in Germany at the close of World War II. The XF-92A used a fully hydraulic irreversible control system for its elevons and rudder. The only airplanes up to this time with fully hydraulic controls were the Northrop XB-35 and the YB-49 flying wings.

AS23190 is a procurement specification that covers a series of plastic and metal components and devices used for the tying, positioning, and supporting cable, cable assemblies, wire, and wire bundles in electrical, electronic and communication equipment, and in interconnection systems.

AS23190 is a procurement specification that covers a series of plastic and metal components and devices used for the tying, positioning, and supporting cable, cable assemblies, wire, and wire bundles in electrical, electronic, and communication equipment, and in interconnection systems.

This specification covers one type of bronze in the form of round wire 0.500 inch (12.70 mm) and under in nominal diameter (see 8.5).