Clock ticking for liftoff of shuttle

CAPE CANAVERAL, Fla. – The countdown for NASA’s return to space began Sunday amid sky-high anticipation, although Hurricane Dennis threatened to interfere with the liftoff of the first shuttle mission in more than two years.

At 6 p.m., the multitude of countdown clocks started ticking down to a Wednesday launch of Discovery. The last time they flashed the hours, minutes and seconds remaining before a blastoff was in 2003, for Columbia’s disastrous flight.

Test director Jeff Spaulding said excitement had been “building” since NASA overcame fuel-tank difficulties that prompted a launch delay a few months ago.

“There’s some excitement for people to get back to launching again and also, I think, maybe a quiet reserve as well, just remembering where we’ve been,” Spaulding said. “But we all do feel confident that we’ve done it right.”

Added payload manager Scott Higginbotham: “It sure does feel good to be back in the saddle again. It’s been too long.”

The effects of Hurricane Dennis, which roared ashore to the northwest, could be felt at the launch site Sunday as the sky was gray and solidly overcast.

Thunderstorms were forecast throughout the week. However, a ridge of high pressure offered hope that the storms may stay away at launch time Wednesday afternoon. Forecasters put the odds of acceptable weather at 70 percent. Because of the hurricane, the mission’s seven astronauts flew in from Houston on Saturday evening, a day early.

Discovery will be making its first flight in four years when it takes off for the international space station with supplies and parts.

Even before Columbia broke up during re-entry on Feb. 1, 2003, Discovery had been undergoing an extensive overhaul. The catastrophe prompted nearly 50 additional modifications, all of which will be demonstrated for the first time on this 12-day test flight. Techniques for inspecting the shuttle’s thermal shield and fixing any holes also will be tested by the crew.

The biggest change, by far, is the redesigned external fuel tank.

Columbia’s fuel tank lost a large chunk of foam insulation at liftoff. The debris slammed into the left wing, smashing a hole that proved catastrophic during re-entry. All seven astronauts were killed.