David Williams, professor of mechanical and aerospace engineering at Illinois Institute of Technology, is a core member of the AVT-239/295 North Atlantic Treaty Organization (NATO) research group that received the 2021 NATO Science and Technology Organization Excellence Award for the team’s high-quality research and impressive collaborative efforts.
Williams says their group stands out for its persistent pursuit of a shared vision and the focus of the team’s leadership. First formed in 2014, the group’s objective has been to improve unpiloted air vehicle performance with a focus on an emerging technique called active flow control.
Active flow control is used to steer aircraft without conventional elements such as fins or tails, leaving what Williams calls “basically flying wings.” It manages this by actively blowing jets of air onto different surfaces of the aircraft body, depending on which way the body needs to be turned.
Active flow control makes aircraft safer to fly in dangerous environments, with the added benefit of offering supermaneuverability beyond what conventional controls will ever achieve.
NATO award candidate technologies were identified, developed, and assessed against key vehicle performance and vehicle integration criteria (e.g. complexity, maintainability, reliability) in order to minimize the reliance on conventional control surfaces during portions of the vehicle mission profiles. The assessment was enhanced by combined experimental and high-fidelity numerical simulations as part of the group achievements. The aerodynamic data was then incorporated into flight dynamics simulations where flow control technologies were used to provide flight control in lieu of conventional control surface deflections.
The Illinois Tech group demonstrated two active flow control approaches, namely tangential blowing on the trailing edge and yaw fluidic thrust vectoring, that when applied in tandem yielded sufficient yaw and pitch control at acceptable levels of engine bleed to provide vehicle control during the ingress mission for two different configurations.
In its announcement of the award, NATO referred to the Illinois Tech group's technology as "an outstanding example of multidisciplinary teaming of academia, government, and industry collaborating to find solutions to complex problems to help the defence of NATO nations."
While the main focus of the NATO group is on designing specialized aircraft, this technology could eventually be used to increase efficiency and reduce costs of commercial aircraft.
Over the years, many Illinois Tech students have made major contributions to the project, bringing the knowledge they’ve learned through their coursework into the lab and gaining professional, real-world experience in the process. “They’ve really gone above and beyond,” says Williams. “It’s also helpful for them to have that experience of serious work where there is an external expectation of results by a particular deadline.”
The NATO group is made up of researchers from government, academia, and industry.
“It’s a very good dynamic among the people in the group. We really work well together, and there are lots of different perspectives,” says Williams. “One member in the group was actually one of the designers of the Concorde [supersonic airliner], so it's a really, really impressive group of people. I'm very proud to be part of it.”
Williams says his NATO research group has been a great resource for exchanging ideas, information, and expertise as he has developed the project. Now, Williams has developed a new active flow control airplane that he has plans to test fly in fall 2021.