Those distortions were corrected before re-use but there were still some problems which were not completely corrected and caused gaps in the seal area. In addition, there were some distortions from the previous use on the rocket boosters. 3) moment of inertia occurs to break the joint where the o-ring seals. When chamber pressure in the rocket booster increased during use, the external walls between joints expanded, called "joint rotation" phenomenon, because the walls of the joint area was thicker than the external walls between the joint areas. In order to prove this, Feynman did the experiment at a public meeting placing an o-ring in ice water to prove the loss of elasticity in the o-ring.Ģ) The investigation has shown that the o-ring manufacturer and NASA knew the problem with o-ring elasticity at low temperature, and the launch continued in spite of the manufacturer's suggestion of canceling the launch.ģ) The direct cause of the o-ring seal failure was loss of elasticity due to low temperature, but faulty design was also a contributing factor. Photo 2 shows black smoke puffing due to the gas leak from the booster before the launch (arrow at right-bottom corner of the photo). It is presumed that fuel leaked from the gas leak inspection hole was ignited by flame from the aft field, and resulting in an explosion. Due to the cold weather, the o-rings stiffened and lost elasticity causing seal failure. The ambient temperature at the day of the launch was -1 to 2 degree Celsius (36 degree F), about 13 to 14 degrees colder than the next coldest previous launch. (1/4 inch thickness and 12 feet in diameter). Some assembly was necessary for these Solid Rocket Boosters at the launch site and O-rings (as shown in Fig. Here, the black smoke is spurting from the rocket booster in front due to the gas leak from the arrowed area, and the picture at the bottom shows white smoke coming out.įeynman, a member of the Presidential Commission headed by William Rogers, discovered the main cause of the explosion as follows:ġ) There were two solid Rocket Boosters on this shuttle for shooting the shuttle into orbit. The above shows pictures of the Orbiter attached facing down. 1 (Photo 1, arrowed) immediately after the launch, and exploded soon after.
On January 28, 1986, the space shuttle Challenger developed flame on the side of the Solid Rocket Booster shown in Fig.
The causes were loss of elasticity in an o-ring due to low temperature and fuel leak due to faulty design.Īs people all over the world watched on TV, the space shuttle Challenger of United States NASA (National Aeronautics and Space Administration) exploded shortly after the launch, and took lives of all 7 members of the crews. 1) exploded immediately after launch, and took lives of all 7 members of the crew. Explosion of the Space Shuttle ChallengerĪs people all over the world watched on TV, NASA's space shuttle Challenger (Fig.