Hurricane Floyd tonight effectively emptied the vast spaceport complex along Florida's Atlantic Coast and threw the U.S. space program into a state of high anxiety.

A sizable percentage of U.S. space assets awaited their fate under the nervous tending of a small band of volunteers deployed about three miles inland from where the launch towers rear up like a string of giant fence posts right next to the surging breakers. The arrival of high winds suddenly gave the launch term "blast danger zone" new meaning.

As most citizens along the threatened central Florida "spacecoast" hurriedly boarded up windows and crawled toward safety along traffic-choked evacuation routes, the small band of technicians and security experts fussed over their hardware and hunkered down with Army cots and rations at NASA's Kennedy Space Center. For the first time in memory, the emergency team planned to evacuate the reinforced confines of the Hurricane Control Center in order to move to "higher ground," a relative term in the exposed alligator-infested swamp flats around the space shuttle launch pads.

"We're only nine feet [above sea level] here," said space center spokesman George Diller, one of the anxious volunteers. He noted that storm surges between 8 and 13 feet high were predicted. As he monitored every nuance in the fluctuating forecasts for the monster storm, he added with a nervous laugh, "Personally, I'm getting a little worried."

Among the assets the team is protecting are four space shuttles, whose replacement value is estimated to be at least $3 billion each. Three of the winged orbiters are in hangar bays rated to withstand winds of up to 105 mph. The fourth is in the gargantuan Vehicle Assembly Building (VAB), the "largest enclosed volume in the free world," as it is described on the tour buses. Like the unoccupied shuttle launch pads, the VAB should be able to withstand winds of 125 mph, Diller said. If the storm made landfall here at full force, the winds could register 145 mph. Diller said "a couple of people" would literally sit next to each shuttle and other pieces of key equipment throughout the storm.

Delays incurred because of the storm threaten to further slow a shuttle launch schedule already running behind for the year because of wiring defects, tardy payloads and other problems.

Just south, on the military turf of Cape Canaveral Air Station and Patrick Air Force Base, officials were not so lucky. Four unmanned rockets are out on the pads in various stages of preparation for upcoming launches. The Air Force had evacuated about 10,000 people from the area by midnight Monday, officials said, sending all military personnel and their families to shelters further inland except for a small security force that was prepared to leave as well if conditions worsened dramatically.

Standing like official greeters of the storm are one Delta, one Titan 4 and two Atlas rockets. Technicians have bolted and tied down enveloping launch towers around the rockets and jacked them up to minimize flood damage, Air Force Staff Sgt. David Byron said.

One rocket, an Atlas, has its payload, a commercial communications satellite, installed, he said. The two Global Positioning Satellites to be launched aboard the Deltas were under safety wraps at a sturdy facility nearby. Only the big Titan is scheduled to carry a military payload, which is "nowhere near being ready," Byron said.

At Kennedy Space Center late yesterday, Wayne Kee, director of emergency operations and preparedness, reduced the "ride-out" team from the normal 120 to 102 people. In the standard hurricane drill, those remaining would all report to the Hurricane Control Center, a reinforced building about 3.5 miles inland that "can withstand pretty much anything--except a flood," Diller said. The plan to abandon that facility was aborted at least temporarily last night because of telephone problems.

Other costly items under threat in nearby facilities include the equipment being readied for a mission to repair the aging Hubble Space Telescope later this fall, a radar mapping instrument scheduled to fly in November and an array of space station hardware.