There will be no official data,the number is come from some reliable military commentators.May be the number is not exactly right,be side effect is truely exist.
That design is for reducing infrared signature,but side effect is that it will make the engine less powerful.And surely you can still have those plate armor around the cockpit, but It will affect the flight performance of the Helicopter or you should reduce the fuel to balance it(as i know,wz-10...
Do you know most of the HK young people choiced BioNTech?Only older expecially age>50 will prefer sinovac,and older is always much more easy dying from coid-19.
IMO,A jet-based stealth UCAV is better.Every "high-cost"UCAV have to be "stealth"or"ultra fast"or both of them,otherwise they will be something expensive but easy to be shot down,just like a toy.
PLAN likes the double-engines J-35 as carrier-borne fighter,but PLAAF don't like it at all=>it's still too expensive and it has a different engine to J-20.