This paper explores some of the potential challenges experienced by the aerospace industry following the introduction of autonomous systems. The automotive industry is currently transitioning to position itself to introduce autonomous cars to the global market. This paper therefore makes suggestions where the automotive industry can potentially benefit from understanding lessons learned from the aerospace industry to understand what is required with regards to producing the safety assurance evidence commensurate to the level of risk, in order to ultimately reduce the cost and development timescales associated with the introduction of safety critical autonomous systems.