This SAE Aerospace Information Report (AIR) reviews the precautions that must be taken and the corrections which must be evaluated and applied if the experimental error in measuring the temperature of a hot gas stream with a thermocouple is to be kept to a practicable minimum. Discussions will focus on Type K thermocouples, as defined in National Institute of Standards and Technology (NIST) Monograph 175 as Type K, nickel-chromium (Kp) alloy versus nickel-aluminium (Kn) alloy (or nickel-silicon alloy) thermocouples. However, the majority of the content is relevant to any thermocouple type used in gas turbine applications.
This SAE Aerospace Information Report (AIR) reviews the precautions that must be taken and the corrections which must be evaluated and applied if the experimental error in measuring the temperature of a hot gas stream with a thermocouple is to be kept to a practicable minimum. Discussions will focus on Type K thermocouples. These are defined in NBS Monograph 125 as nickel-chromium alloy versus nickel-aluminum alloy thermocouples.
To establish a specification for software input and output interfaces for condition monitoring and performance programs used to monitor equipment from multiple manufacturers. The purpose of standardizing these interfaces is to improve operational flexibility and efficiency of monitoring systems as an aid to cost effectiveness (e.g., easier implementation).
The ice bath recommended herein is similar to that described in SAE AIR 46.* Some material not presented in AIR 46, including preferred dimensions, has been added.
This document applies to prognostics of aerospace propulsion systems. Its purpose is to define the meaning of prognostics in this context, explain their potential and limitations, and to provide guidelines for potential approaches for use in existing condition monitoring environments. This document also includes some examples. The current revision does not provide specific guidance on validation and verification, nor does it address implementation aspects such as computational capability or certification.
This SAE Aerospace Information Report (AIR) presents metrics for assessing the performance of prognostic algorithms applied for Engine Health Management (EHM) functions. The emphasis is entirely on prognostics and as such is intended to provide an extension and complement to such documents as AIR5871, which offers information and guidance on general prognostic approaches relevant to gas turbines, and AIR4985 which offers general metrics for evaluating diagnostic systems and their impact on engine health management activities.
SAE Aerospace Information Report AIR1871 provides valuable insight into lessons learned in the development, implementation, and operation of various health monitoring systems for propulsion engines and drive train systems. This document provides an overview of the lessons learned for ground-based systems, oil debris monitoring systems, lubrication systems, and Health and Usage Monitoring Systems (HUMS) for military and commercial programs. For each case study, this document presents a brief technical description, the design requirements, accomplishments, lessons learned, and future recommendations. The lessons learned presented in this document represent a fragment of the knowledge gained through experience when developing and implementing a propulsion health management system. Previous versions of this document contain additional lessons learned during the 1980’s and 1990’s that may be of additional value to the reader.
This SAE Aerospace Information Report (AIR) discusses physical and functional integration of main engine and auxiliary power unit (APU) monitoring with other on-board systems. It includes General Considerations, Parameter Selection and Requirements, Signal Sources, Signal Conditioning, Data Processing, Data Storage, and Data Retrieval. Engine monitoring hardware and software are discussed so that they may be properly considered in an integrated design. Civil and military aviation applications are included and delineated where requirements differ.
SAE Aerospace Information Report (AIR) 4061 provides best practice guidelines for the integration of Engine Health Management (EHM) system functions within aircraft systems to include both its main engine(s) and any Auxiliary Power Unit(s) (APU). This document provides an overview of some of the functions EHM typically integrates, offers some system variations encountered with different aircraft, and suggests general considerations involved with integration. It presents a sample EHM parameter coverage matrix to show the types of parameters with which a typical EHM system might interface, offers insight into signal and data processing and retrieval, and offers a view of typical EHM parameter requirements by function. Where practical, this document delineates between military and commercial practices.
This SAE Aerospace Information Report (AIR) provides an overview of temperature measurement for engine monitoring systems in various areas of aircraft gas turbine engines while focusing on current usage and methods, systems, selection criteria, and types of hardware. This document emphasizes temperature monitoring for diagnostics and condition monitoring purposes.
This Aerospace Information Report (AIR) discusses physical and functional integration of main engine and auxiliary power unit (APU) monitoring with other on-board systems. It includes General Considerations, Parameter Selection and Requirements, Signal Sources, Signal Conditioning, Data Processing, Data Storage, and Data Retrieval. Engine monitoring hardware and software are discussed so that they may be properly considered in an integrated design. Civil and military aviation applications are included and delineated where requirements differ.
This Aerospace Information Report (AIR) provides an overview of temperature measurement for engine monitoring systems in various areas of aircraft gas turbine engines while focusing on current usage and methods, systems, selection criteria, and types of hardware. This document emphasizes temperature monitoring for diagnostics and condition monitoring purposes.
For Engine Monitoring Systems to meet their potential for improved safety and reduced operation and support costs, significant attention must be focused on their reliability and validity throughout the life cycle. This AIR will provide program managers, designers, developers and customers a concise reference of the activities, approaches and considerations for the development and verification of a highly reliable engine monitoring system. When applying the guidelines of this AIR it should be noted that engine monitoring systems physically or functionally integrated with the engine control system and/or performing functions that affect engine safety or are used to effect continued operation or return to service decisions shall be subject to the Type Investigation of the product in which they'll be incorporated and have to show compliance with the applicable airworthiness requirements as defined by the responsible Aviation Authority.
Turbine engine malfunctions account for a substantial portion of the maintenance actions required to keep both fixed and rotary wing aircraft operational. Undetected incipient component failures can result in secondary engine damage and expensive unscheduled maintenance actions. Recent developments of electrostatic methods now provide the potential for the detection of foreign object ingestion and early detection of distress in gas path components. This SAE Aerospace Information Report (AIR) seeks to outline the history of the electrostatic technique and provides examples of state-of-the-art systems for both inlet and exhaust gas debris monitoring systems along with examples of most recent testing.
This Aerospace Information Report (AIR) presents metrics for assessing the performance of diagnostic and prognostic algorithms and systems delivering propulsion health management functions.