* Lockheed, RTX, Northrop added as prime contractors for

command-and-control system

* Space-based interceptors pose scalability and

affordability challenges

By Mike Stone

ARLINGTON, Virginia, March 17 (Reuters) - The price tag

for the Golden Dome missile defense shield has grown to $185

billion, up $10 billion, to accelerate key space-based

capabilities, the program's director said on Tuesday, adding

that Lockheed Martin ( LMT ), RTX and Northrop Grumman ( NOC )

have joined as prime contractors.

Golden Dome envisions expanding ground-based defenses such as

interceptor missiles, sensors and command-and-control systems

while adding space-based elements meant to detect, track and

potentially counter incoming threats from orbit. These would

include advanced satellite networks and still-debated weaponry

in orbit.

"We were asked to accelerate some space capabilities,"

Golden Dome's manager, Space Force General Michael Guetlein,

told the McAleese Defense Programs Conference in Arlington,

Virginia. He identified three programs that would benefit from

the additional funding: the Advanced Missile Tracking

Initiative, a space data network, and the Hypersonic and

Ballistic Tracking Space Sensor, known as HBTSS.

HBTSS is a space-based sensor system designed to detect and

track hypersonic and ballistic missile threats. Its inclusion in

the accelerated funding package signals the Pentagon's urgency

in fielding a persistent overhead tracking capability as

adversaries expand their hypersonic arsenals.

The $185 billion figure covers what Guetlein called the

"objective architecture," a full-capability system to be

delivered over the next decade.

Guetlein rejected outside estimates that have placed the

program's potential cost above $1 trillion, arguing those

figures are based on applying expensive, self-contained

battlefield systems designed for overseas combat to a homeland

defense mission that requires a fundamentally different and

cheaper approach.

"They're not estimating what I'm building," Guetlein said.

Guetlein called the command-and-control system Golden Dome's

"secret sauce." He described a nine-company consortium that

began as a self-formed group of six firms before Lockheed

Martin ( LMT ), RTX and Northrop Grumman ( NOC ) joined as prime partners.

The consortium briefs Guetlein every Thursday evening and

can vote underperforming members out of the group.

The general identified space-based interceptors as the

program's highest-risk element, citing scalability and

affordability as the central challenge. He said directed energy

weapons and next-generation artificial intelligence represent

the most promising technologies for driving down cost-per-kill

and increasing magazine depth.