China is taking a big step towards a bigger, stronger Navy. After weeks of delay, the first made-in-China aircraft carrier has started sea trials. Su Xiaoxiao has more.  

The sea trials are aimed at testing the reliability and stability of the ship's propulsion and other systems. China's current on-duty aircraft carrier Liaoning, is a re-fitted Soviet Union-made vessel. Compared with Liaoning, the new carrier has more space on deck. It can carry more fighter jets, and its radar system is also more advanced. China has a young team to work on development of aircraft carriers. And Beijing expects more in the future.

HU WENMING, GENERAL DIRECTOR CHINA'S FIRST DOMESTICALLY-BUILT AIRCRAFT CARRIER "We now have a team working on the research and construction of the aircraft, with the average age being 36. So we are confident and capable of building more aircraft carriers and surface combatants. We believe our goals will be accomplished soon."

Currently, neither Liaoning nor the new un-named carrier is nuclear powered. China has devoted more spending for its military in recent years. This comes as we've seen an increased U.S. Navy presence in the South China Sea and escalating tensions across the Taiwan straits. Beijing says its military policy is defensive and plans to develop more advanced weapons to protect its territory. The new aircraft carrier is expected to be formally commissioned by 2020. Su Xiaoxiao CGTN.