[Professional Engineer]

The Ruskies copied our shuttle long ago from declassified and unclassified documents, and I believe, actually built an unmanned version of it.

I don't remember if they ever deployed it.

They called it Buran. It was "man rated", at least in the soviet sense. They made one unmanned orbital flight before the program ran out of money.

Energia-Buran sits on the "left" launch pad at Site 110. View from the north. Credit: RKK Energia

Energia-Buran blasts off from Baikonur on November 15, 1988. Credit: RKK Energia

The Antonov-225/Mriya transport plane, carrying Buran orbiter, sits on the runway at Site 251 in Baikonur. Credit: RKK Energia

[Carbonsteel]

Actually, a friend of mine who worked for NASA told me long ago that, the Russians may used our shuttle design as a base, but in the end Buran was for more usable and reliable.

They just ran out of money. The Russian space agency has never had deep pockets and can't afford to throw away money on progams that only halfway work.