– National Interest – The visit of the Chinese Type 039 Song class submarine to Colombo, Sri Lanka, earlier this month passed with little notice, but it’s the first time one of the People’s Liberation Army-Navy’s (PLA-N) diesel-powered submarines has emerged in the Indian Ocean, and its a rare PLAN submarine visit to a foreign port. Naturally, this visit, and an Indian Ocean patrol by a Chinese nuclear submarine at the start of this year, is prompting discussion about the expanding reach and capability of China’s navy.