Herb Matthias, who spent 31 years readying big Titan rockets for liftoff, used to have nightmares that the 30-story mobile gantry he operated blew over in a launch mishap.

At least part of that bad dream will come true Thursday when the final countdown for Launch Complex 41 at Cape Canaveral Air Station hits zero.

But it won't be a rocket that causes that gantry to fall. It will be 180 pounds of high explosives, detonated at 10 a.m. sharp in front of thousands of spectators. When the winner of a $5-a-ticket raffle pushes a ceremonial plunger, 7 million pounds of steel will crash to Earth.

It will be the first time in 23 years that there has been a demolition here.

Lockheed Martin Astronautics of Denver, which sent 27 unmanned Titan rockets aloft from Launch Complex 41, is tearing down the pad's 20-story-tall umbilical tower and a 30-story mobile servicing gantry to build a new launch pad on the same site to support upgraded Atlas 5 rockets.

Matthias, now retired, said he isn't particularly nostalgic about the 34-year-old pad, one of six here, nor is he interested in the engineering involved in its destruction.

"I just want to see it fall," he said, explaining why he wants a ringside seat. "All these years, they talked about maybe it would blow over if we didn't get it pinned down and all that. Well, I want to see it blow over. I want to see what it looks like."

It will be an appropriately explosive end for a launch site that weathered the fire and thunder of the nation's most powerful unmanned rockets for three decades. Used primarily by the Air Force to launch military communications satellites, spy craft and missile warning sentries, pad 41 also sent off NASA's Viking and Voyager probes to explore Mars, Jupiter, Saturn, Uranus and Neptune.

The demolition has become so popular that Lockheed Martin will set up special viewing sites for company workers, VIPs and reporters. Both gantries are visible at the Air Station, the adjacent Kennedy Space Center and on State Road 528, the main artery between Cape Canaveral and Orlando.

A "Demolish the Pad" raffle had sold more than 1,000 $5 tickets as of Friday and "Blasting Out of the Past" T-shirts--showing a rodent pushing a detonator--have been selling swiftly at $10 each. The rodent is a reference to launch pad workers, like Matthias, who call themselves "pad rats."

Proceeds will benefit needy families at Christmas and the raffle winner will symbolically trigger the demolition by pushing the ceremonial plunger.

Lockheed Martin initially planned to cut down the tower and platform. But investigations into a pair of recent Titan failures delayed the start of demolition by six months. Lockheed Martin's contractor, Hensel Phelps Construction Co. of Greeley, Colo., suggested a different approach to make up lost time: implosion.

Lockheed Martin quickly embraced the idea. But one can't detonate so much as a firecracker here without permission from hard-to-please Air Force safety officers. And so, with some trepidation, "we went over to range safety and said, 'Hey, guys, I know you don't like to hear the words explosion or blowing up things, but here's what we're trying to do,' " said Adrian Laffitte of Lockheed Martin. "They went and researched it and said it sounds like a good plan."

The demolition is being orchestrated by Dykon Explosive Demolition of Tulsa. Engineers will weaken the structures by cutting away specific braces and beams. When the explosives detonate, the gantries are supposed to topple like giant trees, falling to the south and breaking into pieces.

"That will allow us to take big chunks of that steel and just haul it out instead of having to take it apart," Laffitte said. "We figure that process is going to take about a month versus three and a half."

He said the implosion technique did not occur first to Lockheed Martin because "we're in a military base and we've got to look to range safety and they're not very excited about us putting explosives on purpose to blow up things when they're [normally] trying to prevent us from blowing things up."

CAPTION: Adrian Laffitte of Lockheed Martin describes the scheduled demolition Thursday of Cape Canaveral's Launch Complex 41, looming behind him.