The outgoing pilots of military helicopters of People's Liberation Army garrison troops in the Hong Kong Special Administrative Region (HKSAR) stand in their formation before leaving Skek Kong Barracks of Hong Kong for their base in the Chinese mainland, Nov. 25, 2008. The Chinese People's Liberation Army garrison troops in HKSAR conducted on Tuesday its 11th troop rotation since it assumed Hong Kong's defense responsibility on July 1, 1997. (Xinhua Photo)