Search Results

This SAE Aerospace Information Report (AIR) describes the different aspects of corrosion on helicopter powerplants, on the components that are affected, and the subsequent consequences on the helicopter, engine durability, performance, and dependability. Guidelines that minimize corrosion during the design stage and during service operation are also discussed.

The purpose of this recommended practice is to establish a standard format for the presentation of helicopter mission data, which will provide data required to establish airframe and/or engine component life.

Turbine engines installed in helicopters require a highly sophisticated oil system to fulfill two tasks: a. Cooling/oil supply b. Lubrication. While lubrication is an engine internal procedure, cooling and oil supply require more or less design activity on the aircraft side of the engine/airframe interface for proper engine function, depending on the engine type. The necessity for engine cooling and oil supply provisions on the airframe can lead to interface problems because the helicopter manufacturer can influence engine related functions due to the design of corresponding oil system components. This SAE Aerospace Information Report (AIR) deals with integration of engine oil systems with the airframe and gives information for both helicopter and engine manufacturers for a better understanding of interface requirements.

Turbine engines installed in rotorcraft have an exhaust system that is designed and produced by the aircraft manufacturer. The primary function of the exhaust system is to direct hot exhaust gases away from the airframe. The exhaust system may consist of a tailpipe, which is attached to the engine, and an exhaust fairing, which is part of the rotorcraft. The engine manufacturer specifies a baseline "referee" tailpipe design, and guaranteed engine performance is based upon the use of the referee tailpipe and tailpipe exit diameter. The configuration used on the rotocraft may differ from the referee tailpipe, but it is intended to minimize additional losses attributed to the installation. This Aerospace Recommended Practice (ARP) describes the physical, functional, and performance interfaces to be considered in the design of the aircraft exhaust system.

This SAE Aerospace Information Report (AIR) outlines a recommended procedure for evaluation of the vibration environment to which the gas turbine engine powerplant is subjected in the helicopter installation. This analysis of engine vibration is normally demonstrated on a one-time basis upon initial certification, or after a major modification, of an engine/helicopter configuration. This AIR deals with linear vibration as measured on the basic case structure of the engine and not, for example, torsional vibration in drive shafting or vibration of a component within the engine such as a compressor or turbine airfoil. In summary, this AIR discusses the engine manufacturer’s "Installation Test Code" aspects of engine vibration and proposes an appropriate measurement method.

A tested method of data presentation and use is described herein. The method shown is a useful guide, to be used with care and to be improved with use.

A general method for the preliminary design of a single, straight-sided, low subsonic ejector is presented. The method is based on the information presented in References 1, 2, 3, and 4, and utilizes analytical and empirical data for the sizing of the ejector mixing duct diameter and flow length. The low subsonic restriction applies because compressibility effects were not included in the development of the basic design equations. The equations are restricted to applications where Mach numbers within the ejector primary or secondary flow paths are equal to or less than 0.3.

Turbine engines installed in helicopters require a highly sophisticated oil system to fulfill two tasks: a Cooling/oil supply b Lubrication While lubrication is an engine internal procedure, cooling and oil supply require more or less design activity on the aircraft side of the engine/airframe interface for proper engine function, depending on the engine type. The necessity for engine cooling and oil supply provisions on the airframe can lead to interface problems because the helicopter manufacturer can influence engine related functions due to the design of corresponding oil system components. This SAE Aerospace Information Report (AIR) deals with integration of engine oil systems with the airframe and gives information for both helicopter and engine manufacturers for a better understanding of interface requirements.

The purpose of this recommended practice is to establish a standard format for the presentation of helicopter mission data, which will provide data required to establish airframe and/or engine component life.

This SAE Aerospace Information Report (AIR) defines the power spectrum during normal and emergency operations of a twin engine helicopter and thereby postulates suitable power plant rating structures. This document does not address the power requirements for single engine helicopters or those with more than two engines.

This SAE Aerospace Recommended Practice (ARP) provides a guide for the preparation of a Helicopter Engine/Airframe Interface Document and Checklist. This document and checklist is intended to provide complete relevant information on the characteristics, performance, and engine interfaces. Of most importance is the identification of the data and the location of data to assure that the engine manufacturer and the airframe manufacturer supply information that can be easily located by either manufacturer.

(This document supersedes and cancels AIR 12) 'Ground resonance' is a term which originated in the early days of autogiro development in this country. It is a somewhat ambiguous term as the conditions it describes usually occur at the ground but do not have any association with the common expression 'ground effect'. However, the troubles usually associated with 'ground resonance' do occur when the ship is on or near the ground.

A tested method of data presentation and use is described herein. The method shown is a useful guide, to be used with care and to be improved with use.