PEARL HARBOR — Just the amount of paint needed to return the Sea-Based X-Band Radar to fresh battleship gray is impressive: three coats of 3,000 gallons each.

The powerful radar, in Hawai'i for repainting and other work before it heads to its homeport of Adak, Alaska, is part of the nation's developing ballistic missile defense program. Its presence yesterday continued to astound those inside Pearl Harbor and out.

Built on an oil rig and topped with what resembles a giant golf ball, the tracking system loomed large at Bravo 1 and 2 piers after arriving Monday afternoon.

The 28-story six-legged rig sits atop the 736-foot semisubmersible ship M/V Blue Marlin. On Saturday, the conglomeration will sail out to open water where the X-Band Radar will float off and then sail back into Pearl Harbor for repainting.

Judd See, 53, who has worked in the shipyard for 25 years, said the arrival of the X-Band Radar was a unique sight.

"It was unbelievable having it come through the channel," the Kalihi man said, noting that he had never seen anything like it.

"Not this size," See said.

"On top of that, it's on a floating dry dock, so to speak. I think probably half the island will see this from their homes."

Maria McCullough, a spokeswoman for Boeing, the prime contractor for the radar system, said while that flying in from Dallas, plane passengers got an aerial view of the 240-foot-wide by 390-foot-long behemoth.

As she recalls it: "There were a fair amount of people that kind of veered over to one side and said, 'What is that thing?' "

Scaffolding was being built yesterday for an elevator that will spare workers the 150-foot climb to the deck.

BAE Systems Hawai'i Shipyards president Roger Kubischta said he'll send a total of about 120 workers to the radar platform for painting and other work. Up to $5 million in work is being performed by BAE.

After the platform returns under its own power Saturday and with additional prep work, painting from the waterline on up will begin. The old paint took a beating during two rounds of sea trials and the 15,000-mile trip to Hawai'i from Corpus Christi, Texas, and around South America — made necessary because the radar platform was too big for the Panama Canal.

The $815 million radar system will be able to track, discriminate and assess a variety of ballistic missile threats with its electromagnetically steered X-band radar.

Reach William Cole at wcole@honoluluadvertiser.com.