Chinese People's Liberation Army (PLA) Navy personnels stand under maritime signal flags on the deck of the Chinese naval guided missile destroyer Haikou (171) during a welcome ceremony as it docks at the Ngong Shuen Chau Naval Base in Hong Kong April 30,

Chinese People's Liberation Army (PLA) Navy personnels stand under maritime signal flags on the deck of the Chinese naval guided missile destroyer Haikou (171) during a welcome ceremony as it docks at the Ngong Shuen Chau Naval Base in Hong Kong April 30, 2012. The destroyer is open to the public for three days, as part of a series of events celebrating the 15th anniversary of Hong Kong's handover to China. (Photo by Felix Wong/South China Morning Post via Getty Images)