Aug 14 (Reuters) - Russia is in the process of equipping its new nuclear submarines with hypersonic Zircon missiles, the head of Russia's largest shipbuilder told the RIA state news agency in an interview published on Monday. "Yasen-class submarines, also known as Project 885M, are nuclear-powered cruise missile submarines, built to replace Soviet-era nuclear attack submarines as part of a programme to modernise the army and fleet. See here for a complete list of exchanges and delays