ABOARD THE USS RONALD REAGAN/ABOARD THE CNS HAIKOU - According to some who were aboard the CVN 76 USS Ronald Reagan at the time, at first they thought they must be mistaken: the Chinese would not have sent a spy ship to gather intelligence on a maritime exercise in which their country was actually participating.

But they did.

This was the first time the Chinese had ever been invited to take part in the annual Rim of the Pacific (Rimpac) exercise, which took place in international waters off the Hawaii coast last month, and also the first known incident in which a participant nation spied on the event. With Rimpac now over, the question remains: Why would a country that so impressed the world’s navies with the capabilities and performance of its most sophisticated destroyer during the exercise – the guided missile destroyer CNS 171 Haikou – taint that showing and insult its hosts by spying?

During the exercise, in stark contrast, the Chinese officers aboard the Haikou were very forthright as they discussed the ship and its capabilities. Standing atop the deck just below the bridge, Chinese People’s Liberation Army Navy (PLAN) officers enthusiastically extolled the attributes of their vertical-launching missile system (VLS).

They pointed out the lid hinges for each of the six cylinders. “They do not need to rotate,” the combat systems officer explained during the rare underway tour of the Haikou, which seems comparable to American Aegis-equipped destroyers.

In an exclusive interview aboard the ship, Senior Capt. Zhao Xiaogang, who was in charge of the task force of ships that participated in the exercise, told Aviation Week through an interpreter, “We are very transparent and open.”

The Chinese ships that participated in Rimpac, he says, show just how far PLAN has come with its design, construction and operational capabilities.

“With this Rimpac, all participating countries can have better understanding about China and [the] Chinese navy,” he says.

While China may have been transparent about showing off the Haikou and its other ships that officially participated in Rimpac, the country’s intentions, especially in the long term, remain opaque or at least vague. Nothing highlights that more than the appearance of the spy ship.

Shortly after Rimpac began in mid-July, according to officers aboard the Reagan, “another Chinese ship just showed up” in the vicinity.

Morning pilot briefings observed by AWIN aboard the Reagan later identified the mystery ship as AGI 853 Dongdiao. Briefers noted its large, white intelligence-gathering domes above the hangar and superstructure, pointed out the Chinese vessel is used for “only passive opportunity” and provided the vessel’s relative location to the carrier.

There certainly was no attempt to hide the AGI 853 – not that the Chinese could keep its presence a secret. But the appearance of the ship befuddled the U.S. and other participants. It was such an odd action that some analysts and regional geopolitical military experts remain uncertain whether this was a calculated Chinese move or just a misstep – an oversight by the nation’s intelligence officials about the strategic military naval importance of appearing to be efficient and polished at Rimpac. How unique would it be, some ask, for the U.S. CIA or NSA to conduct public surveillance without the knowledge of the U.S. Navy or even Pentagon leadership?

For many naval officials, the event epitomized the Asian giant’s seemingly disjointed efforts to be taken seriously as an emerging global naval power.

“That’s the conundrum that is China,” Adm. Harry Harris, the U.S. Navy Pacific Fleet commander, tells Aviation Week. While China has participated in a series of global naval goodwill efforts – helping eliminate Syrian chemical weapons, providing humanitarian aid, helping search for the missing airliner Malaysia Airlines Flight 370 – the nation also has been involved in provocative incidents in the Asia-Pacific that have increased tensions there, he notes.

Officers with the U.S. and foreign navies participating in Rimpac give the Chinese high grades for their ships, crews and seamanship, although some question just how well the Haikou would stack up against the U.S. Navy’s Arleigh-Burke class of destroyers. Upstaging other international navies during its first Rimpac appearance is a feat in its own right, considering the roster included 22 countries, 49 ships, six submarines, more than 200 aircraft and 25,000 sailors, pilots, officers and other personnel exercising June 26 to Aug. 1, in and around the Hawaiian Islands and Southern California in the world's largest international maritime drill.

Harris says he expected growing interest in China, but he has been surprised at the degree. The disproportionate level of interest is heightened by the country’s mystique. The new kid on the block will always get a little extra attention, but when that recent arrival is an Asian giant identified by the Pentagon and many other global military strategists as the emerging near-peer power for the U.S. in the Asia-Pacific and other parts of the globe, the spotlight becomes even more intense.

It has been all China, all the time, Harris says. Even the U.S. and foreign officers on the other ships want to know about the Haikou. How does it compare, they ask, with the Aegis-equipped destroyers that populate the fleets of America and its allies?

The Haikou is a Type 052C, or Luyang II-class, destroyer, launched in October 2003 and commissioned two years later. A wooden plaque hanging in the ship officers’ mess highlights the vessel’s history.

The Luyang-class ships are quite a major improvement over previous Chinese destroyers, according to the U.S. Congressional Research Service (CRS), which says they “are substantially more modern in terms of their hull designs, propulsion systems, sensors, weapons, and electronics.”

CRS says, “The Luyang II-class ships and the Luyang III-class ships appear to feature phased-array radars that are outwardly somewhat similar to the SPY-1 radar used in the U.S.-made Aegis combat system. Like the older Luda-class destroyers, these six new destroyer classes are armed with ASCMs (anti-ship cruise missiles).”

The destroyers are generally believed to be the first Chinese warships to have the ability to truly defend ships against long-range air and missile attacks.

“For others participating [in Rimpac], most of the ships look similar, in terms of outlook, equipment, possibilities,” the Chinese task force senior captain says. “Look at the destroyer from Korea.”

The Republic of Korea sent its guided missile destroyer DDG 993 Seoae Ryu Sungyong to Rimpac, according to the U.S. Navy, where the ship conducted a number of drills, including performing plane-guard duties for the Reagan, in which the vessel patrols near the carrier in case there is a mishap during air operations and sea-based rescues or other assistance is needed.

A KDX-III-class destroyer, according to the Naval Institute’s Guide to Combat Fleets of the World, the ship joined the fleet in 2012, features VLS cells, anti-ship and land attack missiles as well as a 30-mm Goalkeeper close-in weapon system (CIWS) and an Aegis combat system.

The CRS Haikou assessment is right on the mark, officers aboard the Chinese destroyer say. The vessel’s combat system is just as capable as the Aegis shield, the officers contend. “What you have, we have,” the Haikou’s combat systems officer says.

The ship’s 100-mm gun appears to be derived from the French Creusot-Loire T100C, built to battle surface targets, aircraft and missiles flying at low speed with a reported 90 rounds per minute maximum fire rate. The turret is designed to reduce the radar cross section. The ship also has two 30-mm guns.

The VLS is similar to that employed on Russian vessels, with some differences, such as the hinged hatch covers that do not rotate. Both systems are cold-launched, meaning there is no need for the “complex smoke and fire ducts” in the U.S. Mk. 41 VLS, according to authors James Bussert and Bruce Elleman’s recent book, “People’s Liberation Army-Navy, Combat Systems Technology 1949-2011.” The Chinese destroyers are the first ones, the book asserts, equipped with larger versions of the C-802 or C-803 (YJ-83) supersonic missile, with a range of about 250 km at the “subsonic level cruise phase.”

The ship also apparently features the kind of automation that allows its bridge to be run by a handful of officers and crew, similar to that of Norwegian destroyer-like frigates. During the tour of the Haikou, ship officers also pointed out their torpedo-launching capabilities, anchored by two triple 324-mm torpedo tubes.

The earlier Type 052B destroyers combined Russian and Chinese systems, but, Haikou officers say, that is no longer the case. “We have our own systems,” the communications officer says. “Chinese systems.” However, there are some sensors that appear to be from foreign sources aboard the ship.

Like other destroyers, the Haikou comes equipped with a helicopter, slated for antisubmarine and other missions, and the Chinese destroyer brought a Z-9 aircraft – a version of the Eurocopter Dauphin – to Rimpac.

Officers aboard the Haikou say the aircraft has a robust communications and data-processing ability and the Z-9 reportedly can process information in the helicopter because it has the Integrated Processing System (IPS) installed, which is tied to the Haikou, apparently the first Chinese navy ship equipped with the system.

The ship is propelled by a powerplant that combines the power of two Ukraine-made gas turbines with Chinese diesel engines. It can drive the 7,000-ton ship, fully loaded and measuring about 509 ft. in length with a crew of 280, to speeds of at least 30 kt.

While the main mission for U.S. destroyers is to provide protection for the nation’s carriers, Chinese destroyers and frigates spend most of their time on patrol, doing escort duty, conducting antipiracy missions and participating in exercises, the Chinese task force senior captain says.

PLAN is considering different missions in the future for the ships, he says, based on testing and demonstrations being conducted by the service.

The Pentagon, in its recent annual report on China, says, “The first Luyang III-class DDG (Type 052D), which will likely enter service in 2014, incorporates the PLA Navy’s first multipurpose vertical launch system likely capable of launching ASCMs, land-attack cruise missiles (LACMs), surface-to-air missiles (SAMs), and anti-submarine missiles.”

China is projected to need more than a dozen of these ships to replace its aging Luda-class destroyers.

The Haikou features a robust and improved communications network that makes the ship a good command-and-control platform, according to its officers. “We have data link,” both the combat and communications officer point out. The ship also has satellite communications.

According to Bussert and Elleman, the Haikou and sister Chinese “Aegis ships will likely have long-term software headaches, but will provide a new level of command and control.”

Haikou officers say they have resolved command-and-control issues, but that China is still looking to upgrade its destroyers in much the same way the U.S. and other navies are planning – particularly their communications. As more Chinese ships ply international waters, the Haikou’s senior captain is concerned about making sure that the warships, auxiliary ships and other assets can share data, information and otherwise communicate properly.

“We are developing other capacities in this respect,” he says, adding China will continue the outward push of its naval fleet for both missions and exercises.

“For Rimpac, the communications and exchanges form a better part of [the exercise] itself,” he says. “The exercise, briefings, receptions open-ship day activities, the observers, seminars – all of this exchange [makes for a] better understanding of each other and enhances our mutual trust. This is important for cooperation in the future. All of this will be more beneficial to peace in Asia-Pacific.”

But no one – besides perhaps the Chinese – can understand why the Asian powerhouse would send its finest warship and accompanying task force to Rimpac, and also send an uninvited spy ship that forced other navies to curtail some of the operations meant to help foster the very communications the Chinese senior captain is praising.

Aboard the Reagan, for example, pilots noted they would restrain some of their aviation activities because of the nearby Chinese intelligence-gathering vessel. The whole point of Rimpac is to help participating countries avoid such communication breakdowns.