A ship-borne Ka-28 helicopter attached to a destroyer flotilla with the navy under the PLA Eastern Theater Command lifts off from the flight deck of the guided-missile destroyer Taizhou (Hull 138) during a maritime training exercise in late March, 2018. (eng.chinamil.com.cn/Photo by Wen Zidong)

A Ka-28 anti-submarine helicopter of the Chinese People's Liberation Army (PLA) was spotted for the first time near the island of Taiwan on Wednesday, apparently operating from a warship sailing in the region, as Chinese mainland experts said Thursday that the PLA's routine drills near Taiwan likely often feature joint operations of aircraft and vessels, but the defense authority on the island only reported aircraft but failed to track vessels.

Three PLA aircraft, namely a Y-8 electronic intelligence aircraft, a Y-8 electronic warfare aircraft and a Ka-28 anti-submarine warfare helicopter, entered Taiwan's self-proclaimed southwest air defense identification zone on Wednesday, Taiwan's defense authority said in a press release on the day.

This is the first time a Ka-28 helicopter has been spotted operating near Taiwan, and it likely operated from a vessel, media on the island said.

According to the flight path published by Taiwan's defense authority, the Ka-28 took off and landed in the middle of the ocean, and since the Ka-28 is a ship-borne helicopter, it very likely operated from a PLA warship, which sailed in the region, a Chinese mainland military expert told the Global Times on Thursday, requesting anonymity.

The PLA's routine drills have come to a stage where aircraft and vessels hold joint operations, and this is also how modern warfare should be, the expert said, noting that Taiwan's defense authority publishes PLA aircraft operations near the island daily, but it does not show a record of PLA vessel activities.

Song Zhongping, a Chinese mainland military expert and TV commentator, told the Global Times on Thursday that aircraft of both the PLA Air Force and the PLA Navy are active near Taiwan, including ship-borne helicopters.

The Ka-28 has a long endurance and strong anti-submarine capability, Song said, noting that the PLA needs to build a multidimensional anti-submarine network including underwater sonar array, anti-submarine surface vessels and anti-submarine aircraft to deal with submarine threats from external forces.

In addition to PLA aircraft and vessel activities to the southwest of Taiwan, the PLA also sent the Type 052D destroyer Taiyuan through the Miyako Strait on Monday, and dispatched a Y-9 reconnaissance aircraft through the Miyako Strait on Tuesday and Wednesday, according to press releases by Japan's Ministry of Defense Joint Staff.

These routine operations indicate a high combat preparedness of the PLA, analysts said.