Introduction to the Accident
It was a clear sunny day at Kennedy Space Center in Florida with a temperature of 36 degrees which was 15 degrees cooler than NASA has ever sent a shuttle to space. Aboard the space shuttle was a civilian school teacher which made the Challenger such a publicized event. After being delayed five times from bad weather the Challenger was schueled to be launched at 11:38 AM Eastern Standard time on January 28, 1986. Seventy-three seconds after leaving the launch pad 39B the Challenger would explode.
The Challenger Tragedy
The problems started .6 seconds after ignition. With the temperature
at 15 degrees below the NASA experience mark, a black smoke started
to come out of the bottom field joint of the right SRB. The black smoke was the O-Ring s and the joint insulation being burned. The smoke averaged at about three puffs per second. Then the last puff of smoke was seen was at 2. 7 seconds which was an indication that the field joint was not sealed correctly.
The arrow points to the black smoke.
The second problem was at forty-five seconds when three bright flashes were seen on the Challenger's wings. Each flash lasted approximately one thirteenth of a second. When the film was enhanced it is clearly visible that the flashes were coming from the right SRB. The three hundred and five degree flame was coming from the aft center of the aft joint of the SRB. The flame was the gas burning that was coming out of the SRB. At fifty nine point three seconds the flame was clearly visible with the naked eye . As the flame increased in size, the flame had begun to push against the external tank by the rushing air around the orbiter. This made the struts that held on the SRB very weak because of the heat. Sixty four point seven seconds was the first sight that the flame was hitting the external tank. The color of the flame changed. The flame color change indicated that the flame was mixing with the hydrogen substance that the external contained. The top tanks were oxygen and the bottom was hydrogen. The flame also indicated that there was a leak in the hydrogen portion of the external tank. A small glowing light appeared between the external tank and the Challenger's black tiles forty-five milliseconds after the color change.
The small orange glowing light is visible.
When the clock was at 72 seconds there was a sudden chain of events that destroyed Challenger and the seven crew members on board. All of these events happened in less than two seconds. By now the lower strut, that connected the right SRB to the External Tank was very hot and very weak. With the amount of force given by the SRB, the lower strut broke off and away from both the right SRB and the External Tank. Which allowed the right SRB to rotate freely around the top struts. The SRB was out of control, the bottom of the SRB swung around hitting, burning and denting Challenger's wing. At 73.12 seconds into flight a white vapor was seen from the bottom corner of the right SRB. The External Tank was weak because of the intense heat which the flame had produced. The dome structure under the External Tank failed and fell.
The hydrogen inside the external tank acquired a hole and started to release liquid hydrogen contents. Since the hydrogen was out of it's tank the tank shot forward hitting the oxygen tank which also burst. The white vapor seen was the hydrogen and the oxygen mixing. Milliseconds after the white vapor was seen there was an explosion. The challenger was traveling at the speed of Mach 1.92 and at 46,000 when the hydrogen and oxygen exploded. Before the challenger exploded there was a cloud of gray smoke that engulfed the challenger which grew larger but under the gray cloud there was a red smoke which was the control system burning from the wreckage of the challenger . All sorts of debris was falling off of the challenger towards the ocean. Both of the SRB's flew off of the challenger in opposite direct ions. The SRB's were detonated by the United States Air Force 110.25 into the launch. Which was 36.6 second after the Challenger exploded.
What caused this Tragedy?
According to NASA this was the problem.