WASHINGTON/SINGAPORE, Oct 25 (Reuters) - Fearing China

will deploy hypersonic weapons to sink ships in the Pacific, the

U.S. Navy is moving forward with a plan to arm some of its

vessels with Patriot interceptor missiles, two senior defense

officials said.

One industry official said putting the highly agile Patriot

Advanced Capability-3 Missile Segment Enhancement interceptors, used primarily in the U.S. by the Army, aboard

Navy ships anticipates advances in Chinese missile technology,

including the use of highly maneuverable hypersonic weapons.

Integrating the Lockheed Martin ( LMT )-made missiles with

ships' air defenses comes amid simmering tension in the

Indo-Pacific region as China rapidly modernizes its military,

and in the wake of successful missile defense efforts in Ukraine

and the Middle East.

How many PAC-3 interceptors the Navy will need is uncertain,

but overall demand is "through the roof," said Tom Karako, a

missile defense expert at the Center for Strategic and

International Studies in Washington.

He said there was strong interest from foreign governments

adding that the U.S. Army wants to more than double production

in coming years.

The U.S. has tapped Japan, a key ally, as a location for

joint production of Patriot missiles, and Lockheed Martin ( LMT ) wants

to establish a new production line for the missiles' seekers in

Florida, industry sources have told Reuters.

That plant would complement Boeing's ( BA ) seeker

manufacturing efforts, and Lockheed Martin ( LMT ) is pitching the

benefits of additional production to the U.S. Army, which must

sign off on it.

The PAC-3 has already shot down maneuvering hypersonic

missiles in Ukraine. The Navy thinks it could add another

high-probability layer to its anti-missile systems, which have

not been battle-tested against such weapons.

The Navy told Reuters, "More testing is required in the

development roadmap that will include launching PAC-3 MSE from a

ship and validating communication with the SPY-1 radar," the

main sensor in the Aegis missile system.

That follows efforts by the U.S. military that have already

yielded new weapons and new strategies in the Indo-Pacific aimed

at deterring Beijing from a conflict, or winning one if it

occurs.

Beijing's most sophisticated anti-ship ballistic missile,

the DF-27, which uses a hypersonic glide vehicle to maneuver to

its target, was tested in 2023. The Pentagon's China military

report that year said the weapon was "in development".

The PAC-3 is shorter-ranged than the Navy's SM-6 missiles

and cannot reach into space.

But steering rockets near the nose make it more agile, and

destruction of the threat is more likely because of its "hit to

kill" concept, in which the interceptor strikes the target

rather than explode near it, said a missile defense program

director with direct knowledge of the Aegis system.

Facing advanced Chinese weapons, including hypersonic glide

vehicle warheads, those qualities "supplement the existing

missiles on a U.S. ship very well" by being able to more easily

hit high-speed, maneuvering ballistic missiles and destroy them,

said the program director.

Like the industry and defense officials, he declined to be

identified as he was not authorized to speak to the media.

GROWING THREAT

A PAC-3 interceptor from a Patriot missile system, primarily

used by the U.S. Army and allied nations for land-based air

defense, was tested in May on a "virtual Aegis ship" using a Mk.

70 vertical launcher, but has not been deployed on naval

vessels.

In the last year, however, it has intercepted numerous

ballistic threats and aircraft in the Middle East and Ukraine,

including Russia's advanced Khinzal missiles, making it an

attractive addition to Navy magazines, the defense officials and

people familiar with the matter said.

The PAC-3 round is also much smaller than an SM-6 or SM-3,

weighing about 300 kg (660 lbs), compared with 1,500 kg for the

SM-6, and is about 9 cm (3.5 inches) smaller in diameter.

Cost per missile varies by the customer and the deal, but

both are roughly $4 million each, according to estimates.

China has already developed a formidable arsenal of

anti-ship ballistic missiles, including the DF-21D "carrier

killer," and anti-ship warheads for its DF-26 intermediate-range

ballistic missile (IRBM).

Its DF-27, which the Pentagon says could reach as far as

8,000 km (5,000 miles), appears to use an aerodynamic warhead

that can maneuver to evade defences or more easily hit a moving

target, said Tim Wright of the missile defense initiative team

at the International Institute of Strategic Studies.