Data Bases • Custom Term Papers • Free Term Papers • Free Research Papers • Free Essays • Free Book Reports • Plagiarism? Links • Top 100 Term Paper Sites • Top 25 Essay Sites • Top 50 Essay Sites • Search 97,000 Papers @ DirectEssays.com • Search 101,000 Papers @ ExampleEssays.com • Search 90,000 Papers @ MegaEssays.com Free Essays • Term Paper Sites • Chuck III's Free Essays • Free College Essays • TermPaperSites.com • My Term Papers • Get Free Essays • Essay World • Planet Papers	Search Lots of Essays Back to Subjects - Miscellaneous The Challenger The Challenger The skies were clear on the cold freezing morning of January 28, 1986. Kennedy Space Center in Florida was busy preparing the launch of the 25th space shuttle into space. This was one of the most publicized launches because it was the first time that a civilian, a school teacher, was going into space. The launch of Challenger had been delayed five times due to bad weather, January 28 was the coldest day that NASA had ever launched a shuttle. Seventy three seconds into flight, the Orbiter Challenger exploded, killing all seven of its crew. The temperature at Kennedy Space Center was 36 degrees F, which was 15 degrees F colder than any other previous launch by NASA. The Solid Rocket Boosters were ignited, and the thundering noise started. At 0.68 seconds after ignition, videotape showed black smoke coming from the aft field joint of the right SOLID ROCKET BOOSTER. The aft field joint is the lower portion of the Solid Rocket Boosters. The black smoke suggested that grease, joint insulation and rubber O-rings were being burned. The smoke continued to come from the aft field joint facing the Exterior Tank, on cycles of 3 puffs of smoke per second. The last puff of smoke was seen at 2.7 seconds. The black smoke was an indication that the aft field joint was not sealing correctly. The Solid Rocket Booster's are made up of four main segments. They are joined together by a Tang and Clevis joint. Each segment has a Tang on the bottom and a Clevis at the top. The Clevis has a shape like a "U", while the Tang has a shape of a straight line. The Tang would fit by sliding down the sides of the "U" of the Clevis. The Aft Mid Segment connects to the Aft Segment with the Nozzle. The joint that connects these two segments together is called the Aft Field joint. This is the joint that failed on the Right Solid Rocket Booster. The joint is sealed by two rubber O-rings, with a diameter of 0.280 inches (+ 0.005, -0.003). The sealing is used to stop the gases from inside the SOLID ROCKET BOOSTER from escaping. The seal had failed, because the flame seen during There were a few causes that could have lead to joint seal failure. These causes were the joint seal could have been damaged or contaminated during assembly of the Solid Rocket Booster. Second, There may have been a gap opening because when pressure is applied, the gap between the joints open. The cause for the explosion was the failure of the right Solid Rocket Booster aft joint sealing, most likely due to the extremely cold temperature on the morning January 28, 1986. Out of the two Solid Rocket Boosters that were used, the one that was in the extreme cold was the one that failed. O-rings when they are cold do not move as quickly as ones that are warm. And, if the O-rings were nearly frozen in place during ignition, the gases burnt the O-rings and produced the black smoke. Challenger left the launch pad and headed for space. During flight the O-rings continued to not seal the joint, and the gases leaked through the aft field joint. The flame grew larger and later blew Challenger up. Bibliography: Word Count: 557
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