Impact of changing quality of air/fuel mixture during flight of a piston engine aircraft with respect to vibration low frequency spectrum

Abstract

Knowledge about the source of vibrations on a plane is an important prerequisite for modeling adequate response/isolation of initially discovered vibration. The following paper shows results and analysis from changes in low-frequency vibration spectrum located in the engine of Lasta airplane. Due to different working states and various conditions of engine, changing of vibrations is transmitted from the engine to pilot seat, as a consequence of changing quality composition of air/fuel mixture, while testing on a flying plane equipped, with piston propelled propulsion group. Test-measure systems used for researches in vibration dynamics characteristics are shown. Values of vibrations are shown in relation to engine working parameters changes. Research results show that knowledge of engine vibrations gives a wide options for an evaluation of response from piston propeller propulsion group on impact from changing quality composition of air/fuel mixture in the engine leaning process.

Keywords

• piston propeller propulsion group
• engine leaning
• vibrations
• frequency analysis