NASA’s Space Shuttle took 3.5 million pounds of fuel to put it into orbit. A rotating detonation engine is now being investigated as an alternative that requires less fuel. While a mathematical model has been created to show how it works, the engine is currently too unpredictable to put use with a rocket. This new information will enable scientists and engineers to test and develop new ways to create a more stable engine. A conventional engine burns propellant/fuel and then pushes it out the back in order to generate thrust. A rotating engine has propellant flow between cylinders, detonate, and create a stronger pulse of gas with a higher temperature and pressure.