Sunday, January 31, 2016

Challenging The Challenger

     This week marked the 30th anniversary of the tragic Challenger space shuttle disaster. On January 28, 1986, 73 seconds after liftoff, the Challenger shuttle disintegrated 9 miles above the Atlantic Ocean, killing all 7 crew members: Michael Smith, Ellison Onizuka, Ronald McNair, Judith Resnik, Gregory Jarvis, Christa McAuliffe, and Francis Scobee. The Challenger disaster is one of those infamous events where most anyone who was alive can tell you where they were and what they were doing when they heard and saw that it all went wrong.
     The Challenger disaster was not the last time Americans were put into space, but it was the last time NASA ever let a civilian tag along. Keep in mind when I say "civilian", I mean someone who wasn't already a part of NASA.
     As amazing as they were, most people didn't watch space shuttle launches, but this launch was particularly special and buzz worthy because it was going to be the first time ever that NASA was going to launch a "civilian" into space. Christa McAuliffe was a teacher from New Hampshire who won NASA's "Teacher in Space Project" contest, beating out over 11,000 teachers nationwide. While millions were watching live as it was history in the making, many of them children at school, most people learned of the event through tape-delays and news alerts (it was 11:39 am on a Tuesday, and there was no instant Twitter, obviously). When Challenger's journey was cut short 73 seconds after the T-minus, time stopped. No one knew what to think or do.
     After the mission suffered multiple launch delays, an impatience brewed. The launched was finally scheduled for the morning of January 28th, but forecasters were calling for unusually cold weather conditions that morning. Some engineers at Thiokol, a contractor for NASA, expressed concerns about the integrity of the O-rings at that temperature. O-rings were used to create seals in the solid rocket boosters. After tense debate, it was ultimately decided the launch would finally go on. If the main O-ring failed, the second one would pick up the slack, which was the prognosis. Members of NASA and Thiokol were torn. Regrettably, Bob Ebeling, an engineer at Thiokol, told his wife that Challenger would blow up the next day. It happened. To this day, he still blames himself (though he shouldn't, he tried his hardest to get the launch stopped). Roger Boisjoly was the most vocal, but there was no luck.
     The morning of launch, temperatures were between 28 to 29 degrees (-2 to -1.6 C), well below ideal. The previous coldest launch ever had been 53 degrees (11.6 C). Either way, the launch went on as planned. It is important to remember that space shuttles themselves cannot launch into the sky. The two tall white rockets you always saw were "solid rocket boosters", which provided the thrust to push the shuttle up into space. The large orange tank that the shuttle piggybacked on held liquid hydrogen and oxygen (fuel), which was fed into the SRB's, which in turn allowed thrust.
     At T-minus 6.6 seconds, the shuttle engines were ignited, and the SRB's were ignited at T-minus 0. Less than a second later came this eerie sign which shows a puff of smoke coming from the solid rocket booster, where the O-ring was. It was not seen initially, but even if it was, once the SRB's were ignited, they could not be switched off like other engines, other than blowing them up manually (for the safety of people on the ground in case a rocket goes rogue). Because of stress, hot gases began to leak out. Thanks to the cold weather, the O-rings that were supposed to create a seal could not do so. It is believed that if it wasn't for aluminum oxide temporarily sealing the leak, Challenger would've been doomed before it cleared the launch pad.
     58 seconds after launch, a plume of smoke became visible on a tracking camera, but not to the naked eye, anyone on Challenger, at Mission Control, or anyone watching live on CNN. Wind shear eliminated the temporary Al2O3 seal, causing pressure in the SRB to drop. 64 seconds after liftoff, a leak then began in the orange external tank, meaning something had ruptured it. At 73 seconds,  the liquid hydrogen tank was forced into the liquid oxygen tank (both inside the big orange one), and the right SRB ruptured the intertank. The external tank began to disintegrate and milliseconds later, aerodynamic forces and a fireball ripped it all apart. The Challenger technically did not "blow up", but rather disintegrated. The SRB's though did have to be blown up manually afterwards. Momentum carried the crew compartment for another few miles until it gave into gravity and came tumbling back down to Earth. Those who thought the shuttle would fail at launch were initially cheering seeing that they were wrong as the shuttle shot towards the edge of Earth, but they soon realized their celebrations were premature.
     The mood went from cheerful to mournful in minutes. Recovery efforts swiftly began and so did a demand for answers. Ronald Reagan was supposed to give his SOTU that night, but instead devoted the broadcast to Challenger. It is still not understood what exactly happened to the crew immediately after. The originally accepted theory is that the forces caused the crew compartment to detach and depressurize, knocking the crew unconscious within seconds. Today, many see that as a story NASA told as a cover-up to make the country feel better. While no one can say for sure that that theory is wrong, others now believe at least some of the astronauts were awake for much longer, after much analysis and investigation of the wreckage and data. And there are theories today that believe the crew may have unfortunately been alive for the entire descent down until the 200-plus mile per hour and 200-plus g-force collision with the ocean. The remains of the crew and the crew cabin were ultimately found on March 8, 1986 in the Atlantic, 100 feet below the surface, but by then, autopsies were impossible and not every astronaut was able to be identified.
     So why? People still wonder why did NASA decide to launch when optimism wasn't high? First off you have to realize you cannot blame all of NASA. There are certain people to blame, but criticizing the entire organization is too broad. You'd be blaming the astronauts as well in that case. Some people feel the launch went on because the delays were going to throw off time efficiency goals and other crucial satellite launches that NASA had set. Some also feel there was a pride issue: the organization wanted to show that all that brainiac power had no flaws; the shuttle would make it, proving doubters wrong (there was skepticism of the Shuttle program long before Challenger). There is also some who feel the launch went on because President Reagan was supposed to give his SOTU that night, and NASA and the White House wanted to have the launch ahead of the broadcast so Reagan could boast about it. There had also been O-ring issues in the past, but since those missions performed with no issues, some at NASA wrongly assumed that would work all of the time, instead of some of the time.
     And because of that, NASA received major blowback. From the decision to allow a civilian on board, to the decision to not have any type of emergency ejection for the crew, to the decision to allow the launch after warning, jabs came at the organization back and forth, left and right, Rousey and Mayweather. After the tragedy, the state of the shuttle program was put in limbo. The Rogers Commission was founded to investigate the disaster. The O-rings were indeed found as the cause of the disaster by the Rogers Commission and the US House Committee. Afterwards, NASA underwent a major process. Much technical, redesign, management, and testing work was done to keep tragedies like this from ever happening again. After sustaining criticism from just about everyone for the next 2 years and 8 months, the shuttle program was revived and continued with success until 2003. The Space Shuttle was ultimately retired in 2011, but not because of Columbia.
     The Challenger left a lasting legacy that still makes an impact to this day. Schools, buildings,  highways, bridges, and even craters on the moon and mountain ranges on Pluto were named after the astronauts and the shuttle. The 2013 Beyonce song "XO" included a sample of the post-disaster broadcast, causing some controversy of course. Multiple books, TV-movies, and songs are about or make reference to Challenger. The disaster has even become a focus for many case studies ranging from engineering safety to groupthink. Half of the shuttle is still missing, and debris washed ashore in Florida as late as 1996.
     Many obvious lessons have been learned from Challenger, and the disaster changed NASA for the better, but there is still one lesson that seems to not stick in general: if there isn't full optimism, there needs to be action. From Challenger, to Titanic being warned of icebergs, to Louisiana being warned of New Orleans' poor levees, to California being warned of San Francisco's inadequate bridges and overpasses, there is always voices pleading for something to be done. Challenger, and other avoidable tragedies, should serve as a constant reminder that when it comes to large scale, no one cries wolf and it is okay to challenge. The ones that challenge, often end up being right.

*photo credit from Extreme Tech, Wikipedia, CBS News. *Citations: Extreme Tech, Wikipedia, NPR, Gawker, History, Washington Post, NBC News, Forbes.

No comments:

Post a Comment