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This SAE Aerospace Information Report (AIR) describes a method for assessing size dependent particle losses in a sampling and measurement system of specified geometry utilizing the non-volatile PM (nvPM) mass and number concentrations measured at the end of the sampling system.1 The penetration functions of the sampling and measurement system may be determined either by measurement or by analytic computational methods. Loss mechanisms including thermophoretic (which has a very weak size dependence) and size dependent losses are considered in this method2 along with the uncertainties due to both measurement error and the assumptions of the method. The results of this system loss assessment allow development of estimated correction factors for nvPM mass and number concentrations to account for the system losses facilitating estimation of the nvPM mass and number at the engine exhaust nozzle exit plane.

Verification of landing gear design strength is accomplished by dynamic and static test programs. This is essentially a verification of the analytical procedures used to design the gear. An industry survey was recently conducted to determine just what analysis and testing are currently being applied to landing gear. Timing in relation to first flight of new aircraft was also questioned. Opinions were solicited from designers of the following categories and/or types of aircraft: a Military - Large Land Based (Bomber) b Military - Small Land Based (Fighter) c Military - Carrier Based (Navy) d Military - Helicopter (Large) e Military - Helicopter (Small-attack) f Commercial - Large (Airliner) g Commercial - Small (Business) h USAF (WPAFB) - Recommendations It is the objective of this AIR to present a summary of these responses. It is hoped that this summary will be useful to designers as a guide and/or check list in establishing criteria for landing gear analysis and test.

The purpose of this document is to establish the requirements for Real-Time Communication Protocols (RTCP). Systems for real-time applications are characterized by the presence of hard deadlines where failure to meet a deadline must be considered a system fault. These requirements have been driven predominantly, but not exclusively, by aerospace type military platforms and commercial aircraft, but are generally applicable to any distributed, real-time, control systems. These requirements are primarily targeted for the Transport and Network Layers of peer to peer protocols, as referenced in the Open System Interconnect Reference Model (2.2.1 and 2.2.2), developed by the International Standards Organization (ISO). These requirements are intended to complement SAE AS4074 (2.1.1) and AS4075 (2.1.2), and future SAE communications standards.

The purpose of this document is to establish the requirements for Real-Time Communication Protocols (RTCP). Systems for real-time applications are characterized by the presence of hard deadlines where failure to meet a deadline must be considered a system fault. These requirements have been driven predominantly, but not exclusively, by aerospace type military platforms and commercial aircraft, but are generally applicable to any distributed, real-time, control systems. These requirements are primarily targeted for the Transport and Network Layers of peer to peer protocols, as referenced in the Open System Interconnect Reference Model (2.2.1 and 2.2.2), developed by the International Standards Organization (ISO). These requirements are intended to complement SAE AS4074 (2.1.1) and AS4075 (2.1.2), and future SAE communications standards.

Manufacturers/designers of all aircraft equipped with a pallet/container capability have provided a means of linking the ground loaders/elevators with the aircraft sill for the smoother transfer of pallets and containers into or out of the aircraft holds. Use of the aircraft attachment points may be used as a means of averting damage to the aircraft door frames and other important parts. Latch-on guarantees fore and aft and vertical alignment of the loader bed with the aircraft doorway, when used in conjunction with the appropriate ground equipment. This SAE Aerospace Information Report (AIR) has been prepared by SAE Subcommittee AGE-2A to present a review of the current range of aircraft attachment points on wide body aircraft and those narrow body aircraft with a ULD cargo capability. Airline operators, who utilized these facilities, have been faced with a growing number of adaptor bars necessary to suit each type of aircraft and door position.

This document is intended to explain, in detail, the rationale behind the features and functions of the AS4074, Linear, Token-passing, Bus (LTPB). The discussions also address the considerations which a system designer should take into account when designing a system using this bus. Other information can be found in these related documents: AIR4271 - Handbook of System Data Communication AS4290 - Validation Test Plan for AS4074

This document is intended to explain, in detail, the rationale behind the features and functions of the AS4074, Linear, Token-passing, Bus (LTPB). The discussions also address the considerations which a system designer should take into account when designing a system using this bus. Other information can be found in these related documents:

AIR 4065, "Propeller/Propfan In-Flight Thrust Determination" addresses steady state propeller thrust as applied to aircraft which are usually powered by gas turbine engines. It includes theory, examples and methods which have been used. Specifically two methods are discussed, the "J" or traditional J,Cp,Ct, η method including the SBAC variation and a new method we call the "Theta" method which is dependent on knowing blade angle, power/torque and flight Mach number. Implementation guidelines are offered as well as overall approaches to flight testing. Appendices include expansions on theory and testing as well as examples.

Performed tensile and fatigue tests on bolts to determine if cutting of materials flow lines at the bolt underhead would degrade bolt integrity. Five different alloys used in aerospace industry fatigue critical applications were employed to fabricate 5/16 to 1/2 inch diameter bolts. These bolts were machined from bar stock producing fully cut material flow lines under their heads. Tensile testing with and without underhead washers was performed along with industry standard fatigue testing.

Performed tensile and fatigue tests on bolts to determine if cutting of materials flow lines at the bolt underhead would degrade bolt integrity. Five different alloys used in aerospace industry fatigue critical applications were employed to fabricate 5/16 to 1/2 inch diameter bolts. These bolts were machined from bar stock producing fully cut material flow lines under their heads. Tensile testing with and without underhead washers was performed along with industry standard fatigue testing.

A panel of the SAE A-5A Committee prepared this SAE Aerospace Information Report (AIR). The document describes the design approaches used for current applications of Brake-by-Wire (BBW) control systems that are used on commercial and military airplanes. The document also discusses the experience gained during service in the commercial and military environments, and covers system, ergonomic, hardware, and development aspects. The treatment includes the lessons that have been learned during application of the technology. Although there are a variety of approaches that have been used in the design of BBW systems, the main focus of this document is on systems that use the electro-hydraulic method of control. The overall range of implementations is briefly described in 2.3. Sections 3, 4, and 5 describe the electro-hydraulic method in detail.

The Aerospace Recommended Practices of this document are intended for nitrogen-based Flammability Reduction Means (FRM) implemented on transport category, turbine powered airplanes. The recommended practices herein, therefore, relate only to the transport category aircraft, and focus specifically on contemporary inerting systems equipment. Such systems are referred to a Fuel Tank Inerting Systems (FTIS) in this document. This document does not cover the following: Military aircraft applications Air separation technologies other than hollow fiber membrane (HFM) and pressure swing adsorption (PSA) Inerting of conventional unheated wing tanks or aircraft dry bays Expected future technology solutions for the generation of inert gas. The advice contained in this document is aimed towards providing aircraft manufacturers with guidance on the key issues associated with contemporary aircraft fuel tank inerting systems to supplement the guidance in FAA Advisory Circular AC 25.981-2.

These recommendations cover the general field of airplane cabin supercharging equipment and are subdivided as follows:

The purpose of this SAE Aerospace Recommended Practice (ARP) is to standardize locations of aircraft ground service connections to accommodate the trend toward fixed systems, which use the passenger boarding bridge and/or underground “pop-up” or pit systems as a source of utilities. It must be recognized that, in standardizing the locations of the aircraft service connections, they must continue to be served efficiently in those instances where mobile ground support equipment is used. There is an ever increasing number of fixed installations for aircraft servicing. The objectives to be met by standardizing the locations of the aircraft service connections are the following:

This SAE Aerospace Recommended Practice (ARP) is intended as a guide to aid in the specification and testing of Direct Drive Servovalves, but does not include the associated electronic controller. The recommendations contained in this ARP are primarily confined to the input and output characteristics of Direct Drive Servovalves (DDV). The only exception to this approach involves the definition and specification of chip shear force, which is not typically measurable by nondestructive external testing. The information presented should be useful in standardizing the terminology, the specification of physical and performance parameters, and the test procedures used in conjunction with these components. Direct drive servovalves are of two basic types: open loop and closed loop. In the case of open loop direct drive servovalves, the significant input is the motor current as is the case with electrohydraulic servovalves covered in ARP490.

This specification covers manual pressure-generating brake control units as defined by Specification MIL-H-5440.

This specification establishes the design, performance, and test requirements for hydraulic quantity measuring fuses intended to be used for hydraulic circuit protection.