A new material called “active frequency selecting surface” (AFSS) has been created by Chinese scientists from Huazhong University that can grant true stealth to airplanes. The material, which is just 5/16 of an inch thick, covers the aircraft much like skin. The skin reacts to different radar frequencies, adapting in order to make the position of the plane more difficult for radars to pick up.
According to Popular Science, current airplanes try to avoid detection on radar by either incorporating a design that reflects radio waves away from the radar or by using material that turns the radio waves into heat by absorbing them instead of reflecting them back. This technology is used by the U.S. military to protect its planes against Super High Frequency (SHF) radar. However, the stealth technology is vulnerable to ultra-high-frequency (UHF) radar, which can often detect planes that normal radars cannot see.
Because the newly developed material can automatically tune itself to a range of detection frequencies, planes can be protected against a larger range of radar scans — including UHF radar.
According to Ars Technica, the AFSS prototype tested by the researchers was successful in its attempt to absorb radio frequencies between 0.7 and 1.9 GHz, resulting in a reflectivity reduction of 10 to 40dB.
Researchers said that because radar detection equipment is constantly improving, the material will be “widely useful” in hiding from UHF radar.
As radar detection equipment continues to improve, our thin absorbers with broad bandwidth and working in the UHF band will be widely useful.
Scientists have been able to create this type of technology before, but previous attempts were too bulky to use on a plane. “Our proposed absorber is almost ten times thinner than conventional ones”, said primary researcher Wenhua Xu.
Information about the prototype was published by the researchers in the Journal of Applied Physics.