For an example of this from the early Cold War, see the Tupolev Tu-4. The Soviets took the wrecks of three downed US B-29s from WWII and spent huge amounts of m

For an example of this from the early Cold War, see the Tupolev Tu-4. The Soviets took the wrecks of three downed US B-29s from WWII and spent huge amounts of money and manpower studying them and developing copies of them since US strategic bomber tech was so far ahead of their own. Supposedly (though I'd need to find a source again) there was a bullet hole in the wing of one of the recovered B-29s that the Soviets faithfully recreated in the Tu-4 thinking it was part of the actual design. https://en.m.wikipedia.org/wiki/Tupolev_Tu-4 https://en.m.wikipedia.org/wiki/Tupolev_Tu-4