Aircraft Wake Vortices

Trailing vortices are an unavoidable and potentially harmful by-product of fixed-wing aircraft and can persist for many miles behind the vehicle. The imposition of trailing-vortex airplane-separation requirements in 1970 has been a catalyst for significant advances in vortex dynamics – a fundamental discipline at the crossroads of mechanics and physics. A heightened interest in the field came about in the 1990s, motivated by the need to improve airport throughput and by the introduction of a new giant aircraft, the A380. This has stimulated new studies seeking to predict and/or control the natural development of the vortices. This chapter aims to provide the reader with basic notions on fluid mechanics, vortex dynamics, and aerodynamics, which are necessary to appraise both the fundamental and practical facets of the topic. Recent wake vortex research has benefited considerably from concurrent analytical, numerical, and experimental research, and we used results from these different domains to exemplify the concepts. The chapter ends with a short summary on current research and on perspectives of the topic.