The aerospace industry demands some of the highest levels of integrity for safety critical applications. With the constant drive to improve fuel efficiency, more and more control functionality is being targeted at the software, with a corresponding growth in the hardware platform which supports that software. However, aerospace gas turbine engine controls have to survive in a very challenging environment, yet still meet cost, weight and reliability targets. The talk will explain some of the background to why Rolls-Royce Controls and Data Services developed its own processor for safety-critical applications, and the challenges associated with that strategy.