995. Design and Development of Lightweight Wheel Braking Equipment

Paper

Abstract

Aircraft brake duty is severe and a considerable heat sink, and hence weight and volume material is unavoidable. It is practice, however, to fit enough of the heavy wearable material to the aircraft to last many months of aircraft operation.
A fresh look at potential materials led to the development over recent years of new types of brake heat packs. These include beryllium and carbon/carbon composite which have provided major weight benefits but also have disadvantages including high cost. Comparisons are made between the various types of heat pack, and their relative cost effectiveness to constructors and operators is discussed.
Brake structures have also been improved as a result of a critical and parametric study of the design and available materials. Not only was the original objective of improved wear performance achieved but a weight saving was also made.
Brief comment is given on the alternative materials used for wheels and why aluminum alloy remains the first choice. The wheel fatigue life can be altered by change in section thicknesses, and hence weight, of the wheel. A method of analysis to assist in choice of most desirable wheel weight for minimum total operating cost is evolved. This is a guide which becomes significant in applications where the monetary value of saving on structure weight is high.
Finally, a brief indication is given of future possible design trends in wheel and brake equipment in order to make existing weight savings more applicable to the less sophisticated aircraft and to provide still greater weight savings for special applications.