Pilot training uses different aircraft based on the training stage, starting with simple single-engine planes like the Cessna 172 or Piper PA-28 Cherokee for basic flying due to their low cost, safety, and ease of handling. As students progress, they move to more advanced aircraft like the Diamond DA42 for multi-engine training and complex systems. Aircraft choice depends on cost efficiency, safety features, and the skills required at each stage, ensuring gradual learning and better pilot development.