The space shuttle was revolutionary for its time. What went wrong?

The CNN original series “Space Shuttle Columbia: The Final Flight” uncovers the events that led to the disaster. The four-part documentary ends at 9pm ET/PT on Sunday.

Upon its inception, NASA’s space shuttle program promised to usher in a new era of exploration by keeping astronauts in space with a reusable and relatively inexpensive ride to orbit. It was a project that forever altered the course of spaceflight with its triumphs – and its tragic failures.

Considered a “engineering marvel”, the first of five winged orbiters – the space shuttle Columbia – made its maiden flight in 1981.

Twenty-two years and 28 trips into space later, the same shuttle broke apart during its final return to Earth, killing all seven crew members on board.

The tragedy spelled the end of the US space agency’s transformative space shuttle program. And his memory continues to reverberate in the halls of NASA today, leaving a lasting mark on his regard for safety.

“Human history teaches us that in exploration, after accidents like this occur, we can learn from them and further reduce the risks, although we must honestly admit that the risks can never be eliminated,” he said then.–NASA Administrator Sean O’Keefe, who ran the agency from 2001 to 2004, in a speech before members of Congress shortly after the Columbia disaster.

After the space shuttle program was withdrawn, no U.S. astronaut would travel to space in an American-made rocket for almost a decade.

Reimagining rockets

The space shuttle project was forged in the optimism of NASA’s Apollo program, which landed 12 astronauts on the surface of the Moon and defeated the United States’ Soviet rivals during the Cold War.

Apollo was, however, extraordinarily expensive: NASA spent US$25.8 billion (or more than $200 billion when adjusted for inflation) — according to a cost analysis by space policy expert Casey Dreier of the nonprofit Planetary Society.

With financial constraints on the horizon, by the mid-1970s NASA engineers were building an entirely new means of space transportation.

Apollo used towering rockets and small capsules—intended to fly only once—that would dive from space back home and parachute to land in the ocean.

The space shuttle concept was a notable pivot: reusable winged orbiters would take off tethered to rockets, sail through Earth’s orbit, and glide to an airplane-like landing. From there, the shuttle could be refurbished and flown again, theoretically reducing the cost of each mission.

The legacy of the bus

Over three decades, NASA’s space shuttle fleet has flown 135 missions — launching and repairing satellites, building a permanent home for astronauts with the International Space Station, and commissioning the revolutionary Hubble Space Telescope.

But the space shuttle program, which ended in 2011, never lived up to the U.S. space agency’s initial expectations. vision.

Each bus launch cost around US$1.5 billion on average, according to a 2018 paper by a researcher at NASA’s Ames Research Center. That’s hundreds of millions of dollars more than the space agency waited for at the beginning of the program, even when adjusted for inflation. Long delays and technical setbacks also hampered his missions.

“Every mission I’ve been on there has been canceled, rescheduled, postponed because something wasn’t exactly right,” O’Keefe, a former NASA administrator, said in a new CNN documentary series, “Space Shuttle Columbia: The Final Flight.”

And two disasters – the Challenger explosion in 1986 and the loss of Columbia in 2003 – cost 14 astronauts their lives.

The Columbia Disaster: Looking Back

On the morning of February 1, 2003, the orbiter Columbia was returning home after a 16-day mission to space.

The seven-person crew on board performed dozens of scientific experiments while in orbit, and the astronauts were scheduled to land in 9:16 am ET in Florida.

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NASA engineers knew that a piece of foam — used to insulate the space shuttle’s large orange fuel tank — had ruptured during the Jan. 16 launch, striking the Columbia orbiter.

The space agency’s position, however, was that the lightweight insulation material likely did not cause significant harm. Some foam had ruptured on previous missions and caused minor damage, but was considered an “accepted flight hazard,” according to the Columbia accident official. investigation report.

It was later revealed, however, that concerns about the foam’s impact had been swept under the rug by NASA management, according to previous reports. communicating It is “Space Shuttle Columbia: The Final Flight.”

“I was very upset, angry and disappointed with my engineering organizations, from top to bottom,” Rodney Rocha, NASA’s space shuttle chief engineer, said in the new series.

The astronauts even received a email from mission control alerting them to the foam attack on the eighth day of the mission, assuring them there was no cause for alarm, according to NASA.

But the assumption was wrong.

An investigation later revealed that dislodged foam hit Columbia’s left wing during launch, damaging the spacecraft’s thermal protection system.

The problem did not affect the crew while they spent more than two weeks in space.

But protection from the heat is crucial for the dangerous return home. As with all missions that return from orbit, the vehicle had to dive back into the thickness of Earth’s atmosphere while still traveling at more than 17,000 miles per hour (27,359 kilometers per hour). Pressure and friction in a spacecraft can heat the exterior to 3,000 degrees Fahrenheit (1,649 degrees Celsius).

Re-entry was too much for the damaged Columbia shuttle. As the vehicle approached its destination, crossing New Mexico into Texas, the probe began to disintegrate – visibly releasing chunks of debris.

At 8:59 a.m. ET, ground controllers lost contact with the crew.

The final dispatch came from mission commander Rick Husband, who said, “Roger, uh,” before being interrupted.

At 9 a.m., onlookers saw the Columbia explode in East Texas and watched in horror as it covered the area with debris.

The realities of risk

Two decades later, the Columbia tragedy and the broader shuttle program offer a crucial perspective on the perils and triumphs of spaceflight.

NASA entered the era with confidence, anticipating that the chances of a space shuttle being destroyed mid-flight were about 1 in 100,000.

The space agency reassessed this risk, estimating after the Challenger disaster that the space shuttle had a one in 100 chance of disaster.

“If someone told me, ‘Hey, you can get on this roller coaster and there’s a 1 in 100 chance you’re going to die. Well, there’s no chance in the world — no chance in hell — that I’m going to do that,” U.S. Senator Mark Kelly, a former NASA space shuttle astronaut, told “The Final Flight” documentary makers.

“But I also think people often think it won’t be them,” Kelly added.

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