Gears Steer New Engine Designs

New aircraft designs boost engine demand

Demand for lower fuel consumption, more power and improved reliability keeps engine manufacturers constantly renewing their market offerings. Simultaneously, the growing number of aircraft models on the market, due to both the emergence of the very light jet (VLJ) segment and the numerous derivative designs aircraft makers are marketing, demands an ever expanding range of engines. In its busine...

New ANSI/AGMA Accuracy Standards for Gears

Time for a Change For many years, the U.S. system of gear accuracy tolerances has been provided by AGMA 2000-A88, Gear Classification and Inspection Handbook. This document has been commonly used for gear accuracy specifications in contractual agreements for vendor-supplied gears. Also, it has often been used as the basis of internal company gear tolerance systems. The material within AGMA 2000...

Future Aero Engine Designs: An Evolving Vision

The Effects of Using Noise Reduction Turbofan Engine Nozzle Designs on a Turbojet Engine

Aircraft noise is a complex topic which is projected to increase with the increasing number of aircraft and size of the engines. Turbine-powered aircraft produce sounds that are considered pollutants at certain decibel levels. Turbofan engines are inherently quieter than turbojet engines for a given level of thrust. The purpose of this research is to determine if current turbofan noise reductio...

Spatial involute gearing - a new type of skew gears

This is a geometric approach to spatial involute gearing which has recently been developed by Jack Phillips [4]. Due to Phillips' fundamental theorems helical involute gears for parallel axes (Fig. 2) serve also as tooth flanks for a uniform transmission between skew axes, and the transmission ratio is even independent of the relative position of the axes.