1) Aircraft technical training historically separated theoretical classroom training and practical hands-on training, but virtual training tools now allow merging the two.
2) Virtual practical trainers (VPTs) were introduced to supplement hands-on training by practicing aircraft systems operations virtually, reducing costs and risks.
3) The current evolution is a common Virtual Technical Training tool that combines e-learning, computer-based training, and VPTs to successively provide theoretical and practical training lessons and activities.