TBO.com - TBO is Tampa Bay Online

Almost Home: The Columbia Space Shuttle Disaster

ADVERTISEMENT

The Tampa Tribune

Published: February 2, 2003

CAPE CANAVERAL - As it hurtled into the atmosphere at 18 times the speed of sound Saturday morning, space shuttle Columbia, the oldest in the nation's fleet, seemed destined for a routine landing at Kennedy Space Center. Ground controllers even marveled how unusually well the weather had cooperated.

In many ways, the flight of STS-107 seemed little different from more than 100 that preceded it, save for extra security measures because of an Israeli astronaut aboard.

Relatively few Americans even knew astronauts had gone up again Jan. 16, and Mission Control went about the usual business of monitoring the spacecraft's carefully orchestrated return to Earth. For all its turns and engine firings, Columbia was on track, on time and angled correctly for a safe return.

"Everything from a flight control perspective was perfect," said shuttle program director Ron Dittemore.

At 8:03 a.m. EST, the shuttle soared 176 miles above the Indian Ocean, properly upside down and backward. At 8:15 — precisely on time — the engines fired, lurching the seven astronauts back in their seats. Pilot William McCool then spun the craft around, nose first. He pulled it up on its tail, necessary preparation for skidding from 17,500 mph to an eventual 200 mph above Florida. Still business as usual.

By 8:45, high above the Pacific Ocean, the actual skidding began, like doing a wheelie on ever-thicker air. Intense friction heated the shuttle to about 2,500 degrees Fahrenheit. Through the windows, the astronauts probably witnessed the usual flares of white, pink and red against the darkness of space.

Then, 16 minutes before scheduled touchdown, things quickly went awry.

Between 8:53 a.m. and 8:59 a.m., a succession of 12 temperature, tire pressure and structural sensors on the craft's left side went dead. NASA officials said it was as if wires had been cut. In the last transmission about 9 a.m., the crew seemed to be responding to an alert. The spacecraft was 207,000 feet above Earth.

"Columbia, Houston," said Mission Control. "We see your tire-pressure messages, and we did not copy your last."

"Roger, uh, buh ..."

Then the radio fell silent.

Nobody at Mission Control panicked at first. From the days of U.S. astronaut pioneer John Glenn, people on the ground have grown accustomed to lapses in communication during re-entry.

"Continuing to stand by," said the calm voice of Mission Control.

Nothing.

"Columbia? Houston. UHF comm check."

Nothing.

The azure skies of north-central Texas reverberated with the sound of two booms — either sonic or explosive — and were scarred by multiple long white contrails of debris, which soon rained on homes, parking lots and fields. The debris field stretched from eastern Texas to northwestern Louisiana. NASA warned people not to touch the potentially toxic wreckage.

Within minutes, the ordinary had turned extraordinary, delivering to Americans another tragic reminder of an inescapable truth: No matter how great the progress and seeming perfection of the machines of mankind, no matter how ordinary and fail-safe things may seem, accidents will happen.

Certainties will give way to perplexing mysteries, and the most powerful nation on Earth — and in space — will again find itself unsettled by disturbing signs of vulnerability.

"In an age when spaceflight has come to seem almost routine, it is easy to overlook the dangers of travel by rocket and the difficulties of navigating the fierce outer atmosphere of the Earth," President Bush said in a televised speech to the nation.

NASA executive William Readdy, a former astronaut, said the tragedy was a "very stark reminder that this is a very risky endeavor, pushing back the frontier" of space. "Unfortunately people have a tendency to look at it as something that is more or less routine. Well I can assure you, it is not."

But what was the cause? Terrorism? A failure of the craft's heat shield? The fatigue of metal or parts on an older spacecraft? Could it have been a computer error? Might a speeding meteorite or debris in orbit have caused such a calamity?

By late Saturday, all except terrorism seemed plausible theories. For a nation still enduring the effects of the Sept. 11 attacks, and on the verge of war against Iraq, even terrorism seemed a possible explanation. Sabotage is the "very first thing that comes to mind," said Florida Sen. Bill Nelson, a former astronaut.

Yet authorities say it would be hard for terrorists to have a reach that extends so far above Earth, or to breach layers of security that surrounded this shuttle flight. "It's very unlikely," Nelson agreed. "That thing is scrubbed and scrubbed and rescrubbed."

In the coming days, special teams of investigators from NASA and an independent Mishap Investigation Board will attempt to figure out what went wrong, partly by gathering wreckage and reassembling it in one place, like a jigsaw puzzle with missing, melted, charred and twisted pieces. From the reassembled remains of Columbia, investigators will comb for clues.

The focus will be on those critical few minutes between the shutting-down of sensors on the spacecraft's left side and the fiery fall to Earth.

Already, the leading theory focuses on possible damage to special tiles meant to shield the shuttle from intense heat as it skids through the upper atmosphere.

The reason: Only 81 seconds after takeoff 16 days ago, debris from foam insulation on the craft's external tank broke loose, hitting the left wing. If the foam damaged the shield in some way, the shuttle might have been vulnerable when it most needed protection from temperatures of 3,000 degrees and was subject to such forces that even minor navigational errors could prove destructive.

"We can't discount there might be a connection" between the incident at takeoff and Saturday's tragedy, said Dittemore. Some aeronautical specialists suspected a smoking gun, but Dittemore cautioned that "a lot of things in this business look like the smoking gun — and turn out not to be the smoking gun."

Even so, NASA officials acknowledged that, shortly after liftoff, they had been sufficiently anxious about possible damage to the tiles to convene a special team to consider the problem. According to Dittemore, they reassured themselves "technically and analytically" no damage occurred.

None of the judgments were based on close inspection of the heat shield. That was impossible. Flights such as this one, involving no scheduled spacewalks, lack the equipment — mainly a robotic arm and connections for a tether — necessary for the job, NASA spokesman Bruce Buckingham confirmed.

After more than 100 flights, NASA officials believed in the dependability of the shuttle's design.

"You fly with the understanding you're not going to have tile problems because it's all engineered to not expect problems," Buckingham said. "You don't have contingency plans if it's not expected."

Other possible causes: A leak or explosion involving the fuel and oxidizers aboard Columbia. Kept under high pressure, they are highly flammable.

Then again, the shuttle itself may have been structurally weak; older aircraft develop metal fatigue, and parts wear out. Also possible: faulty programming of computers guiding navigation on re-entry. Bad directions from a computer could cause a poorly timed or angled maneuver.

Earth's orbit is littered with other objects, from bits of meteoroid rock to space junk, debris from other missions. This, too, could have caused a problem.

It was almost 17 years to the day that the Challenger shuttle exploded Jan. 28, 1986, also killing the seven astronauts — also five men and two women — onboard.

"They were an inspiration to us," Columbia commander Rick Husband radioed Earth only days ago, on the anniversary of the Challenger tragedy. Then the astronauts held a moment of silence for the others who had made "the ultimate sacrifice."

The Columbia crew included the first Israeli to fly the shuttle, 48-year-old Col. Ilan Ramon. Although there was no indication of foul play, and experts doubted terrorists would be able to cause any problems aboard the aircraft at such a height, military and space officials convened emergency meetings to assess the situation, and Bush rushed to the White House from Camp David to reassure a nation unsettled anew.

Although it is an axiom of flight that takeoffs and landings are the most dangerous periods of flight, in 42 years of U.S. spaceflight there has never been an accident on descent to Earth.

Despite all the talk of risks and causes, Jane Hodges, a Brevard County nominee to become a teacher in space, still wants to go up.

She had been writing her essay to compete for a slot on a future space shuttle mission when a friend called from Tampa to tell her of the disaster. She hurried to Kennedy Space Center to learn more and sat in on the press conference.

Then she decided.

"It's been my dream for 30 years to go up in the shuttle," she said. "Now I think I'm going to go on and finish my application."

Share this:

Loading Comments...

Email Print

ADVERTISEMENT