Conclusion and a Look Ahead

For more than 50 years now, NASA has methodically and, for the most part, quietly advanced the state of art of propulsion technology. With the basic design of the jet engine unchanged since it was invented dur­ing World War II, modern jet engines incorporate every lesson learned during NASA’s past five decades of research. As a result, jet engines are
now quieter, safer, more fuel-efficient, less expensive to operate, and less polluting, while being easier to maintain. And thanks to advancements in computers and simulations, new engines can be tested for thousands of hours at a time without ever bending one piece of aluminum or braid­ing a square yard of composite material.

So what’s in store for propulsion technology during the next few decades? More improvements with every possible variable of engine operations are still possible, with future advances more closely linked to new aircraft designs, such as the blended wing and body in which the engines may be more fully integrated into the structure of the aircraft.

In a feature story written in April 2009 for NASA’s Aeronautics Research Mission Directorate Web site, this author interviewed sev­eral key Agency officials who are considering what the future holds for engine development and making plans for what the Agency’s approach will be for managing the effort. Here is that look ahead.