The media reported that the United States received technology from Russia to develop the Compound Coaxial Helicopter (CCH) attack helicopter.
According to Lenta.ru, referring to The Aviationist, Soviet technology was transferred to the United States.The chief executive of U.S. helicopter developer AVX said the Russians were remarkably open about their technology.They have been flying coaxial helicopters for years.
According to the director, Russian specialists presented technical papers at various meetings.They developed a criterion for spacing between screws, which turned out to work.
It is noted that the engineering solutions that the Russians used in the design of the Ka-50 and Ka-52 helicopters allowed the Americans to improve the characteristics of their device.