The skies were clear on the cold freezing morning of January 28, 1986. KennedySpace Center in Florida was busy preparing the launch of the 25th space shuttleinto space. This was one of the most publicized launches because it was the firsttime that a civilian, a school teacher, was going into space. The launch ofChallenger had been delayed five times due to bad weather, January 28 was thecoldest day that NASA had ever launched a shuttle. Seventy three seconds intoflight, the Orbiter Challenger exploded, killing all seven of its crew. The temperature at Kennedy Space Center was 36 degrees F, which was15 degrees F colder than any other previous launch by NASA. The Solid RocketBoosters were ignited, and the thundering noise started. At 0.68 seconds afterignition, videotape showed black smoke coming from the aft field joint of the rightSOLID ROCKET BOOSTER. The aft field joint is the lower portion of the SolidRocket Boosters. The black smoke suggested that grease, joint insulation andrubber O-rings were being burned. The smoke continued to come from the aftfield joint facing the Exterior Tank, on cycles of 3 puffs of smoke per second. Thelast puff of smoke was seen at 2.7 seconds. The black smoke was an indicationthat the aft field joint was not sealing correctly.The Solid Rocket Booster's are made up of four main segments. They arejoined together by a Tang and Clevis joint. Each segment has a Tang on thebottom and a Clevis at the top. The Clevis has a shape like a "U", while the Tanghas 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 theNozzle. The joint that connects these two segments together is called the AftField joint. This is the joint that failed on the Right Solid Rocket Booster. The jointis 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...
