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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.

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.

These recommendations are written to cover the testing of air conditioning equipment functioning as a complete and installed system in prototype civil aircraft for the purpose of: A Demonstrating the safety of the installation and equipment. B Demonstrating performance of the installation and equipment. a Source of heat b Source of fresh air and/or ventilation c The cooling system d Distribution system including ducting, joints, etc. e Water separator f Exhaust system g Temperature control system. h Cabin pressurisation system including flow and pressure controls. C Obtaining data for future design and to aid in the analysis of in-service performance of the systems and equipment.

A life support system (LSS) is usually defined as a system that provides elements necessary for maintaining human life and health in the state required for performing a prescribed mission. The LSS, depending upon specific design requirements, will provide pressure, temperature, and composition of local atmosphere, food, and water. It may or may not collect, dispose, or reprocess wastes such as carbon dioxide, water vapor, urine, and feces. It can be seen from the preceding definition that LSS requirements may differ widely, depending on the mission specified, such as operation in Earth orbit or lunar mission. In all cases the time of operation is an important design factor. An LSS is sometimes briefly defined as a system providing atmospheric control and water, waste, and thermal management.

The prediction of vehicle temperatures during ascent through the earth’s atmosphere requires an accurate knowledge of the aerodynamic heating rates occurring at the vehicle surface. Flight parameters required in heating calculations include the local airstream velocity, pressure, and temperature at the boundary layer edge for the vehicle location in question. In addition, thermodynamic and transport air properties are required at these conditions. Both laminar and turbulent boundary layers occur during the boost trajectory. Experience has shown that laminar and turbulent heating are of equivalent importance. Laminar heating predominates in importance in the stagnation areas, but the large afterbody surfaces are most strongly affected by turbulent heating. Once the local flow conditions and corresponding air properties have been obtained, the convective heating rate may be calculated for a particular wall temperature.

The prediction of vehicle temperatures during ascent through the earth’s atmosphere requires an accurate knowledge of the aerodynamic heating rates occurring at the vehicle surface. Flight parameters required in heating calculations include the local airstream velocity, pressure, and temperature at the boundary layer edge for the vehicle location in question. In addition, thermodynamic and transport air properties are required at these conditions. Both laminar and turbulent boundary layers occur during the boost trajectory. Experience has shown that laminar and turbulent heating are of equivalent importance. Laminar heating predominates in importance in the stagnation areas, but the large afterbody surfaces are most strongly affected by turbulent heating. Once the local flow conditions and corresponding air properties have been obtained, the convective heating rate may be calculated for a particular wall temperature.

The purpose of this report is to provide information on ozone and its control in high altitude aircraft environmental systems. Sources of this information are listed in the selected bibliography appearing at the end of this report, to which references are made throughout.

This SAE Aerospace Information Report (AIR) provides Nuclear, Biological and Chemical (NBC) protection considerations for environmental control system (ECS) design. It is intended to familiarize the ECS designer with the subject in order to know what information will be required to do an ECS design where NBC protection is a requirement. This is not intended to be a thorough discussion of NBC protection. Such a document would be large and would be classified. Topics of NBC protection that are more pertinent to the ECS designer are discussed in more detail. Those of peripheral interest, but of which the ECS designer should be aware are briefly discussed. Only radiological aspects of nuclear blast are discussed. The term CBR (Chemical, Biological, and Radiological) has been used to contrast with NBC to indicate that only the radiological aspects of a nuclear blast are being discussed.

This SAE Aerospace Standard (AS) covers combustion heaters and accessories used in, but not limited to, the following applications: a Cabin heating (all occupied regions and windshield heating) b Wing and empennage anti-icing c Engine and accessory heating (when heater is installed as part of the aircraft) d Aircraft deicing

Heat transfer is the transport of thermal energy from one point to another. Heat is transferred only under the influence of a temperature gradient or temperature difference. The direction of heat transfer is always from the point at the higher temperature to the point at the lower temperature, in accordance with the second law of thermodynamics. The fundamental modes of heat transfer are conduction, convection, and radiation. Conduction is the net transfer of energy within a fluid or solid occurring by the collisions of molecules, atoms, or electrons. Convection is the transfer of energy resulting from fluid motion. Convection involves the processes of conduction, fluid motion, and mass transfer. Radiation is the transfer of energy from one point to another in the absence of a transporting medium. In practical applications several modes of heat transfer occur simultaneously.

Heat transfer is the transport of thermal energy from one point to another. Heat is transferred only under the influence of a temperature gradient or temperature difference. The direction of heat transfer is always from the point at the higher temperature to the point at the lower temperature, in accordance with the second law of thermodynamics. The fundamental modes of heat transfer are conduction, convection, and radiation. Conduction is the net transfer of energy within a fluid or solid occurring by the collisions of molecules, atoms, or electrons. Convection is the transfer of energy resulting from fluid motion. Convection involves the processes of conduction, fluid motion, and mass transfer. Radiation is the transfer of energy from one point to another in the absence of a transporting medium. In practical applications several modes of heat transfer occur simultaneously.

These standards are written to cover internal combustion heat exchanger type heaters used in the following applications:

These specifications are written to cover the subject of exhaust hot air type heaters under three classifications, namely. A EXHAUST HOT AIR TYPE HEATERS - GENERAL - Dealing with features applicable to all makes and users. B EXHAUST HOT AIR TYPE HEATERS - MILITARY AND COMMERCIAL -Covering features applicable to military and commercial aircraft. C DESIRABLE DESIGN FEATURES - General information for use of those concerned with meeting requirements contained herein.

This ARP discusses design philosophy, system and equipment requirements, installation environment and design considerations for systems within the ATA 100 specification, Chapter 36, Pneumatic (reference 1). This ATA system/chapter covers equipment used to deliver compressed air from a power source to connecting points for other systems such as air conditioning, pressurization, anti-icing, cross-engine starting, air turbine motors, air driven hydraulic pumps, and other pneumatic demands. The engine bleed air system includes components for preconditioning the compressed air (temperature, pressure or flow regulation), ducting to distribute high or low pressure air to the using systems, and sensors/instruments to indicate temperature and pressure levels within the system. The engine bleed air system interfaces with the following ATA 100 systems: The interface with these systems/chapters is at the inlet of the shutoff/control valve of each associated system.

This document considers the cooling of equipment installed in equipment centers, which usually consist of rack-mounted equipment and panel mounted equipment in the flight deck. In instances where these two locations result in different requirements, these are identified. For purposes of this document, the cooled equipment is referred to generally as E/E equipment, denoting that both electrical and electronic equipment is considered, or as an E/E equipment line-replaceable-unit (LRU). The majority of cooled equipment takes the form of LRUs. This document primarily relates to E/E equipment which is designed to use forced air cooling in order to maintain the equipment within acceptable environmental limits, in order to maintain equipment operating performance (within acceptable tolerances), and to maintain reliability. Cooling may be applied internally or externally to the case of the item of E/E equipment.

This document considers the cooling of equipment installed in equipment centers, which usually consist of rack-mounted equipment and panel mounted equipment in the flight deck. Instances where these two locations result in different requirements are identified. This document generally refers to the cooled equipment as E/E equipment, denoting that both electrical and electronic equipment is considered, or as an E/E equipment line-replaceable-unit (LRU). The majority of cooled equipment takes the form of LRUs. The primary focus of this document is E/E equipment which uses forced air cooling to keep the equipment within acceptable environmental limits. These limits ensure the equipment operates reliably and within acceptable tolerances. Cooling may be supplied internally or externally to the E/E equipment case. Some E/E equipment is cooled solely by natural convection, conduction, and radiation to the surrounding environment.

This document supplements and in some cases supersedes the recommendations presented in ARP 85D, which refers to subsonic civil transports.

The environmental factors of prime importance in the transport of animals in aircraft are air temperature, humidity and carbon dioxide concentration, and of course space (or volume) limitations. Secondary factors are air velocity, noise, lighting, etc. Pressure isnot addressed herein as pressure levels and rates of change are totally dictated by human occupancy requirements. Some basic governmental documents, such as References 1, 2 and 3, define overall requirements for animal transportation, but with very limited data on environmental requirements. Reference 4 gives some airplane characteristics measured during animal transportation from the USA to foreign destinations. Temperature and humidity profiles are indicative of airplane characteristics. This report presents information on the temperature, humidity, ventilation, and carbon dioxide limitations and the metabolic heat release rates for animals which will allow the determination of the environment required by th animals.