This time we are talking about the future of speed in the air. What is the difference between supersonic and hypersonic travel, what speeds might we reach in the future and how can engines achieve this? Since the grounding of Concorde there has been no supersonic commercial air travel – but with new start-ups appearing globally, is that all about to change?  And what are the implications of hypersonic speeds for global security? Helen is joined by Conrad Banks. Conrad is the Chief Engineer for Defence Future Programmes and Research and Technology for the Aerospace division of Rolls-Royce plc., where he is responsible for new propulsion system technology for future military aerospace requirements. An aeronautical engineer, Conrad’s career is based on engine performance and controls, and he has held various roles in engineering and management at Rolls Royce, which have included projects such as engines for the Harrier and Eurofighter Typhoon aircraft, and propulsion for the Taranis Unmanned Combat Aircraft. The Zero Pressure podcast series is looking at how science and technology positively can contribute to solving complex, interrelated global challenges of today and tomorrow. We look at pioneering technologies and speak to those on the thinking edge. Zero Pressure is a podcast from Imperial College London and Saab. A relaxed conversation with those on the cutting edge of science and technology - hosted by Britain's first astronaut Helen Sharman - Presented by Imperial College London and Saab.