Complex sentence: The HAL HTT-40 aircraft project is a Hindustan Aeronautics Limited (HAL) is the indigenous replacement for the Indian Air Force's retired HPT-32 Deepak as a basic trainer.
Split into simpler sentences: The HAL HTT-40 is an Indian training aircraft, design and built by Hindustan Aeronautics Limited (HAL). It will replace the Indian Air Force's retired HPT-32 Deepak as a basic trainer.