Could it be that perhaps they have a way to detect this 5/16 material that is not being disclosed? And they want others to use the detectable material they created?

Even after billions and billions of dollars spent on the stealthy skin used on F-22, F-35 and B-2, the material has weaknesses, and one of those is ultra-high-frequency (UHF) radar, which can pick up traces of the plane that other radar misses.

 Chinese researchers came to the rescue and created a material just 5/16 of an inch thick that can safeguard stealth planes against UHF detection. 

The material tunes itself to a range of detection frequencies, protecting against a large swath of radar scans. What's even more amazing? 

They published this seemingly top secret invention wide open in the Journal of Applied Physics .