This!
As far as I know, the Soviets were designing aircraft to be able to respond to the F22 aircraft. However, it was never put into production. And remember, the stealth plane idea was originally the idea of a Russian physicist.
Here's this guy.
https://en.wikipedia.org/wiki/Pyotr_Ufimtsev
These guys, in the late '80s, could well have designed a stealth hull. What could be more natural than to base that design on? And that way you need less of the British.
Couldn't we, who received Ukrainian assistance in the auxiliary power unit, also get the airframe design from the same guys? Why did you explode in anger at my words?
Did you think I was an idiot who didn't know what to write?