It was certainly derived from the Blackhawk. I see this as akin to the F2 and the F16. To discount that these 2 helos have absolutely nothing in common is hogwash.
I am not sure if "not copy" (my words) equals to "absolutely nothing in common".
If you go to extreme end to interpret or understand one's words, you can always find something to disagree.
All these words are subjective depending how one defines it. Most people would agree that J-11A is a copy of Su-27. J-11B is less, then J-11D, then J-16 etc. We all agree that they are still in the Flanker family, but are they copies? Maybe, maybe not, depending on who is speaking. Will anyone claim J-11D and J-16 have "absolutely nothing in common" with Su-27? I surely won't say that. So why would you think I meant it in Z-20 case?
I don't understand what makes you so excited. Did my post hurt you somehow because it sounded like I was discrediting Blackhawk?
Let me make my definition (you don't need to agree with me) clear. J-11A is a copy of Su-27 even with Chinese made components because J-11A did not change anything in design of Su-27. Other Chinese Flankers are derivatives, just like Su-35, Su-33 etc. are derivatives of Su-27. Derivatives are NOT copies in my opinions because there are lots of redesigns. Now I apply this definition to Z-20, it is designed based of the exact operation profile of Blackhawk, there is no other helo in the world that has the same operation profile, by operation profile I meant my previous words "field of application". In terms of operation profile and doctrine, it is a copy. But the design has many significant differences that warrant it a different design. IF Harbin produced Blackhawk and now comes up with Z-20, one can call it a derivative BUT NOT a copy just like the Flanker case.
In case of F2 and F16, I don't call them copy. F2 has lots of redesign work, I call it a F-16 derivative, not a copy and NOT "absolutely nothing in common". And the difference here is that Harbin does not have Sikorsky as a design partner. That makes Z-20 further away from Blackhawk than F2 from F16.