Extended reality has long been utilized in the games industry and is emergent for pilot training in the military and commercial airline sectors. This paper follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology to present a systematic quantitative literature review (SQLR) on the use of extended reality in flight simulators. It also encompasses recent studies of teaching and learning in immersive, virtual environments in non-aviation disciplines. The review identified 39 papers spanning all areas of the virtuality continuum across academic, commercial, and military aviation sectors, as well as engineering and medicine. The SQLR found that extended reality in flight simulators is being introduced in the commercial and military aviation sectors. However, within academia, hardware constraints have hindered the ability to provide positive empirical evidence of simulator effectiveness. While virtual reality may not replace traditional flight simulators in the near future, the technology is available to supplement classroom training activities and some aspects of simulator procedure training with promising cognitive learning outcomes. However, its usefulness as a mechanism of skills transfer to the real world has not been evaluated, highlighting numerous research opportunities.