I do get tired of the copying argument. Yes as Max said they copied some stuff but I can't see how you can acuse the Russians of copying the US when you put a Flanker next to an F-15. Planform is different.
The thing is if you give two independent sets of designers the same problem chances are they will come up with similar looking solutions.
The move with the Tu-4 was very smart and caught the west out. A lot of innovative development came out of that. If you take a look at the protoypes the Russians came up with and some that didn't get past the drawing board you will see that they were capable of coming up with some very advanced thinking. I also wouldn't say they are 10 years behind. No more behind than europe is from the US and I wouldn't say that is very far behind either. Just because we don't make an F-22 type plane doesn't mean we can't.
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