This story is Chapter 2 in an 11-part series by Florida Today.

The rain never seemed to stop. The cold, the wet, the tired, hundreds of searchers huddled in bleachers of a rodeo arena in Nacogdoches, the small Texas town where many of the remnants of the destroyed shuttle Columbia had fallen to Earth.

Some came from the space program, like that fast-talking blond woman in the blue NASA ballcap shouting instructions. Most were not NASA people.

They were forest rangers and firefighters, chicken farmers and payroll clerks, doctors and air-conditioning repairmen.

People from all walks of life, most of them volunteers, came to help clean up after a national disaster.

Stephanie Stilson came from Kennedy Space Center, where she was in charge of readying shuttle Discovery for its missions.

Stilson, an energetic, fast-rising NASA manager from Cocoa, arrived in Nacogdoches two weeks after the accident, overseeing one of the rural buildings the government took over in Texas and Louisiana to collect and sort out the pieces of Columbia.

Working from daybreak to dusk, 25,000 people slogged through skin-stinging sleet, thorny brambles and thick mud, searching for the shattered remnants of NASA's oldest orbiter and the remains of seven astronauts.

It was the largest search-and-recovery effort in U.S. history, one that cost almost a half-billion dollars. Every morning, Stilson would give the same pep talk to her small share of dedicated troops.

"Yesterday, we found this. Today, we really need to find that. You guys are doing great. Keep it up."

Tired as the searchers were, Stilson had to force people to go home, especially the NASA folks seeking the piece of the puzzle that might reveal what had gone so horribly wrong.

EAST TEXAS
Searching for debris in extreme conditions

At least the NASA people had hotels.

"There were tents everywhere. That's where they lived," said Michael Mohr, 38, a shuttle propulsion system engineer with United Space Alliance. "They had to curl up in their tents in 20-degree weather, sleep, and get up the next day and go at it again."

Temperatures rarely topped freezing at night. There were no televisions or radios, no heat. Latrines and showers were trucked in on semitrailers. Still, searchers crawled out of sleeping bags at 5 a.m. every day and ate breakfast in windswept mess tents.

Then they set out into a cold, rainy wilderness with poisonous snakes, ticks, fire ants, wild hogs, testy bulls, nasty armadillos, prickly cactus and dense briar patches.

They mounted horses to search sprawling landfills and rode all-terrain vehicles on a lookout for propellant-laced wreckage that could hurt some curious onlooker. Some dove in ponds, lakes and reservoirs; others soared over the landscape in contraptions called powered parachutes. A select few boarded 37 helicopters enlisted to fly dangerous "low-and-slow" missions that ultimately claimed two lives and injured three others.

The search required 100-hour weeks to cover the 2,400-square-mile swath of debris roughly from Corsicana, Texas, to Fort Pork, La.All the while, everyone hoped not to be the one to stumble across "HR" -- code for human remains.

Searchers worked until suppertime, with few breaks other than a brown-bag lunch. "They really wanted to be the team that found the piece, whatever it was, that would answer the riddle," Mohr said.

SEVEN MILES EAST OF HEMPHILL, TEXAS
Crater holds recorded clues to ship's demise

A nippy morning offered a welcome break from the rain. For once, the sun peeked out from behind the clouds.

They were stretched out in a quarter-mile line, walking 10 feet apart, climbing a rising slope when they saw it. A black box that looked like a bulky old VCR lay out in the open next to the small crater it made when it crashed to Earth.

"NASA!" screamed a member of the team of about 40 forest rangers from Florida and a few space workers.

George Atkins -- a second-generation space worker who grew up with rockets on the Space Coast -- could see tape spools through a broken side panel in the metal case. Other than ash-gray streaks, the box was in pretty good shape.

"I knew it was some type of recording device, and it had NASA markings on it, so I knew it was from the shuttle," said Atkins, 43, a married father of two from Merritt Island who works for shuttle contractor United Space Alliance. "I knew it was something important."

More important than Atkins could have imagined.

It was Columbia's Orbiter Experiments recorder, one of the "hot items" sought by crash investigators.

The reason: Data stored on the reel-to-reel tape -- if retrievable -- might confirm a leading theory on the cause of the disaster.

Forty-six days had passed since the accident. Investigators suspected a chunk of external tank foam insulation hit Columbia's left wing 82 seconds after launch, compromising the heat shield. But they didn't think the strike was forceful enough to down a shuttle. But lacking forensic evidence, they started to doubt they would ever determine with 100 percent certainty what caused the disaster.

The 22-year old recorder, tucked into a bay below Columbia's crew cabin before its first flight in 1981, was not designed to withstand a shuttle breakup or the fall back to Earth. But it did.

Engineers salvaged 9,400 feet of magnetic tape with data from hundreds of sensors that measured strains, stresses, temperatures and pressures on the shuttle. Better yet, the recorder automatically turned on 15 minutes before Columbia began its descent and kept running until 18 seconds after 9 a.m. -- a full 47 seconds after NASA lost contact with the crew and orbiter.

The black box changed the investigation.

The sensor data showed where the superhot gas got inside the wounded wing. It told the path the heat followed as it tore through the wing like a blowtorch. Investigators could recreate where and when the heat melted the aluminum framework, and ripped the ship to shreds.

KENNEDY SPACE CENTER
Truckloads of pieces present challenges

The tractor-trailers just kept coming. Columbia was coming home in pieces.

The astronauts' belongings -- a helmet, a glove, a singed snapshot and other sobering items -- rode across Louisiana, Mississippi, Alabama and Florida in the passenger seats of the cabs.

Steve Altemus and Jon Cowart were among the shuttle managers assigned to "reconstruct" Columbia. Airplane investigators do it all the time when a jetliner drops from the sky. It's a lot harder when half of the aircraft is missing, burned up in the atmosphere or lost in wilderness somewhere between California and Texas.

Ultimately, the team got back about 40 percent of Columbia in more than 82,500 pieces.

Skeptics wondered about the exhaustive effort to catalogue every suspected shuttle piece. The occasional bizarre items shipped back to KSC -- a bowling ball, for instance -- bolstered doubters.

As the reconstruction team spread the pieces across a hangar floor, a pattern emerged. They had more pieces of the right wing than the left wing, and the pieces were bigger. The KSC team built clear plastic molds of the front edges of the shuttle's wings, replicas of the 22 taco-shaped panels that protect the front of each wing from the extreme heat the ships endure re-entering Earth's atmosphere. Then, workers stuck inside the plastic model each piece of the reinforced carbon-carbon material from the panels, a sort of forensic jigsaw puzzle. The clue emerged over weeks.

If unfound fragments of the wing panels -- the ones that left holes in the model -- had burned up or had come off first, there was only one conclusion: There was a big hole somewhere about the eighth or ninth of the 22 panels on the left wing.

The science wasn't perfect, but it was another clue matching what most people already suspected: There had been a hole in the same spot on the wing where the foam had hit.

SAN ANTONIO
Air cannon test leaves little doubt about cause

"Phoom!"

Scott Hubbard lowered his binoculars. He grabbed his gut.

"Oh my God," he mouthed, blinking his eyes. No sound came out.

Gasps erupted from the investigators, shuttle engineers and reporters in the bleachers.

Fifty yards away, investigator Hubbard's attempt to replicate what happened to Columbia ended in a split second.

An air cannon shot a briefcase-sized chunk of foam at a life-size orbiter wing at the very speed the debris hit Columbia after launch. No one needed binoculars to see the result. The foam smashed a hole the size of a large pizza in the wing.

Hubbard dashed from the bleachers, not to where men were sticking their head and shoulders inside the hole to peek around, but to a bank of monitors nearby. He wanted to see the slow-motion video from cameras inside the wing. The films showed the heat shield panel bending, then breaking, shards exploding all over the inside of the wing. There was no doubt now.

Hubbard rung the Columbia Accident Investigation Board chairman, retired Navy Adm. Harold Gehman.

We have our proof, Hubbard said. The foam did it.

Hubbard clicked the cell phone off, walked over to reporters and trumpeted the end of the physical part of the Columbia investigation. NASA was wrong. Almost six months after the accident, in July, the board finally proved beyond a doubt that foam could down a shuttle.

"We have found the smoking gun," Hubbard said.

WASHINGTON, D.C.
No more mistakes, time for accountability

NASA Administrator Sean O'Keefe did not agree with everything the Columbia Accident Investigation Board had to say in August 2003.

The probe didn't stop at the foam strike. The investigators dug deep into far-flung corners of NASA's spaceflight program, uncovering decades of bad decisions and flawed assumptions that let the foam problem linger unfixed until it killed Columbia's crew.

On top of that, mission managers clung to their assumptions, missing opportunity after opportunity to recognize the danger and try to do something to save the crew. And, investigators said, O'Keefe and his deputies put too much pressure on managers to meet a political deadline for finishing construction of the International Space Station. Staying on schedule dominated as people made fateful choices before and during the flight.

Whether he agreed or not, O'Keefe knew seven astronauts were dead. Two billion dollars worth of irreplaceable space history was strewn across the countryside. It was time for a mea culpa.

O'Keefe and his handlers reached years into his past, to when President Bush's father tapped him to clean up the Navy after the Tailhook sexual harassment scandal.

O'Keefe met the nation's press the day after the Columbia report came out with the same three-word sound bite he uttered in his pledge to fix Tailhook.

"We get it."

Published under license from FLORIDA TODAY. Copyright © 2005 FLORIDA TODAY. No portion of this material may be reproduced in any way without the written consent of FLORIDA TODAY.

         Florida Today Special Report: NASA's Return to Shuttle Flight

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