Science | May 21, 2017 5:00 am

Air Force Cadet Invents Bullet-Stopping Goo

Shear thickening fluid, Kevlar and carbon fibers combined for first time.

Air Force Cadet 1st Class Hayley Weir has developed a goo that, when struck by a bullet, hardens enough to stop it.

Weir came up with the idea during an Air Force Academy chemistry class, during which she was given three materials to combine in a way that could both stop a bullet without shattering. Weir experimented with epoxy, Kevlar and carbon fiber, and consulted with a chemist who suggested swapping out the epoxy for shear thickening fluid.

Shear thickening fluid changes viscosity under stress or force, so it’s gooey until a bullet strikes it, at which point it hardens.

With encouragement from her professor, Weir began researching in earnest in 2015, and her ballistic goo had its first successful test in December 2016. Weir’s plans for the goo include using it as extremity armor for vehicles and aircraft, as well as material for emergency barricades.