Challenger 1986
Written by Tega Jessa

The Challenger disaster was a tragic shuttle accident that was almost the death knell of manned spaceflight for NASA. The incident occurred on January 28, 1986 at around 11 pm. The incident was further magnified by the fact that the launch was highly publicized since it involved the inaugural mission of the Teachers in Space program. It is said that over 85% of Americans knew of the Challenger disaster within an hour of its occurrence.
To understand how it happened we need to look at some of the key factors that came together to make the incident happen. First there were the solid rocket booster. These were fabricated by a contractor for NASA. However there had been warnings about serious flaws. These warnings surrounded the O rings that held the rockets to the shuttle. The other factor was the weather. The Challenger launch had been delayed by a previous shuttle mission and weather conditions. Unfortunately the day of the set launch date the temperatures dropped to an unusually cold 31 degrees Fahrenheit or -1 degrees Celsius. This was actually the minimum temperature allowed for a shuttle launch.
What happened afterwards would be one of the most horrifying and tragic incidents in aeronautics. The launch went on as normal but for a key problem with the O rings. The problem was actually a flaw by the contractor that had been worked around rather than addressed. This had to do with the metal in the SRB's structure warping or extruding under the extreme heat of the hot gases leaving them. This would produce gaps in the shell that could be deadly. However the Engineers had noticed in most launching conditions the O ring would slip and form a seal that fixed the problem on its own. So they left the booster rockets as is. However the cold weather made the O rings too hard to undergo extrusion. This caused the gaps in the booster rockets that would lead to the Challenger's destruction.
The rest happened very quickly. The joints that attached the SRBs to the shuttle and main tank were torn of by the heated gases that escaped and strong wind sheer. The shuttle and the main booster then rapidly disintegrated as the craft became parallel with its original trajectory and succumbed to the dynamic pressure of traversing the atmosphere at high speeds. All the crew members were immediately killed.
The Challenger disaster resulted in a 32 month review of the shuttle program as officials sought to make sure that the incident could never happen again. Some important recommendations were made but still it is likely not all of them were completely carried out due to costs and design demands. The disaster brought to the American public's consciousness the real risks and dangers involved with space flight.
If you found this article informative and interesting there are other articles on Universe Today that you will enjoy. There is another article about the space shuttle Challenger explosion. There is also an article about Christa Auliffe the teacher who died on Challenger.
You can also find some great resources online. You can check out the Challenger incident web page at NASA.gov. You can also check out mahal.org.
You can also listen to Astronomy Cast. Episode 127 is about the U.S. Space Shuttle.
Filed under: Astronomy
Tags: aeronautics, space disasters, Space Flight
