MATERIAL SELECTION FOR AN ENGINE EXHAUST OF A UTVA 75 LIGHT AIRCRAFT USING A SYSTEMATIC APPROACH

Abstract

The Sudanese air force college trains its pilots using a world-renowned light aircraft for basic pilot training called UTVA-75, during operation in the climate of Portsudan the exhaust tubes experienced failure in the shape of cracking and therefore become dangerous to operate. The study tackles the issue from a material point of view, as properties that eliminate or reduce cracking or any failure are essentially material properties. The research examines material selection methods to identify a method that implements a systematic approach to selection, provides a ranking process, bases its selection on material properties and incorporate a material database for selection. Michael Ashby’s method was selected above methods used in material selection such as cost vs performance, failure analysis, value analysis, benefit cost analysis and preferential ranking after it fulfilled the research requirements. Fracture toughness and density were the two properties that material selection was based on and upon implementing the method stainless steel was identified as the suitable material for the exhaust pipe. The results were compared to exhaust pipes of aircrafts which were similar in category to the Utva 75 aircraft to verify the results. The results however did not identify the exact grade of stainless steel and further studies are required to correctly identify the grade of stainless steel.