"Xuehu" radar stealth and obvious optical characteristics were actually not due to the design team's lack of consideration.
As early as when they were testing engines on unmanned platforms, they had already thought about this issue. At speeds above Mach 10 in hypersonic flight, air will produce a large amount of plasma due to violent collisions, which in turn emit a variety of electromagnetic waves including visible light and infrared characteristics.
The original team came up with a method: they applied an electric field at the engine's air intake, directing the plasma to flow along the desired route over the aircraft body, eventually merging with the engine's wake.
The constrained plasma formed an elliptical cloud surrounding it, not only absorbing many bands of electromagnetic waves to enhance stealth, but also dissipating to significantly reduce detectability.
