1. Executive Summary
The NASA space shuttle Challenger exploded on January 28, 1986, just 73 seconds after liftoff, bringing a devastating end to the spacecraft’s 10th mission. The shuttle was in its 1st stage ascent at 46000 feet, Altitude when it disintegrated. The disaster claimed the lives of all seven astronauts aboard, including Christa McAuliffe, a teacher from New Hampshire who would have been the first civilian in space.
The failure occurred due to a structural design flaw in the joint that engineers had known right before the launch. The low temperatures at launch caused O-rings, sealants used in the joints, to harden. This led to the escape of hot gas as O-ring did not fully seal at the low temperatures because the decision was made …show more content…
Further previous tests and flights indicated that there was distress (damage) in the O- rings which they were not designed for. However, these were agreed to be ‘acceptable risks’. All this goes against a ‘fail-safe’ design philosophy.
4. Driving and Interacting Failure Mechanisms
The main cause of the accident was the failure of aft O – Rings of the right Solid Rocket Booster which allowed ‘Blow-By’ leading to eventual disintegration. However, there are many other interacting mechanisms which led to the failure. The sequence of events leading up to the disintegration can be summarized as follows:
1. Plumes of Black smoke at ignition indicate leakage of combustion and burning of O-ring
2. Aluminium in fuel forms slag reducing evidence of leak as the slag blocks leakage.
3. The ship performs a normal roll. Due to heavy cross winds, the shuttle had to perform greater corrective manoeuvring than on any previous …show more content…
(Refer to Appendix A for structural details). Joint sealing is provided by two rubber O-rings with diameters of 0.28 inches. However, after assembly, the rings were compressed to a thickness as low as 0.004 inches. In the assembled configuration zinc chromate putty was intended to act as a thermal barrier to prevent direct contact of combustion gas with the O-rings. However, it was found that the rings often suffered burn damage or erosion. This was taken as an acceptable risk since the secondary O-ring was still completely
The NASA space shuttle Challenger exploded on January 28, 1986, just 73 seconds after liftoff, bringing a devastating end to the spacecraft’s 10th mission. The shuttle was in its 1st stage ascent at 46000 feet, Altitude when it disintegrated. The disaster claimed the lives of all seven astronauts aboard, including Christa McAuliffe, a teacher from New Hampshire who would have been the first civilian in space.
The failure occurred due to a structural design flaw in the joint that engineers had known right before the launch. The low temperatures at launch caused O-rings, sealants used in the joints, to harden. This led to the escape of hot gas as O-ring did not fully seal at the low temperatures because the decision was made …show more content…
Further previous tests and flights indicated that there was distress (damage) in the O- rings which they were not designed for. However, these were agreed to be ‘acceptable risks’. All this goes against a ‘fail-safe’ design philosophy.
4. Driving and Interacting Failure Mechanisms
The main cause of the accident was the failure of aft O – Rings of the right Solid Rocket Booster which allowed ‘Blow-By’ leading to eventual disintegration. However, there are many other interacting mechanisms which led to the failure. The sequence of events leading up to the disintegration can be summarized as follows:
1. Plumes of Black smoke at ignition indicate leakage of combustion and burning of O-ring
2. Aluminium in fuel forms slag reducing evidence of leak as the slag blocks leakage.
3. The ship performs a normal roll. Due to heavy cross winds, the shuttle had to perform greater corrective manoeuvring than on any previous …show more content…
(Refer to Appendix A for structural details). Joint sealing is provided by two rubber O-rings with diameters of 0.28 inches. However, after assembly, the rings were compressed to a thickness as low as 0.004 inches. In the assembled configuration zinc chromate putty was intended to act as a thermal barrier to prevent direct contact of combustion gas with the O-rings. However, it was found that the rings often suffered burn damage or erosion. This was taken as an acceptable risk since the secondary O-ring was still completely