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| S uccessThe Wright Brothers Flyer Failures
A new program was initiated in the 60’s, encouraged by the government and fueled by the engineering and technological advancement of space exploration, manned space flight was born. With confidence and stride of unmanned Saturn V successful navigation into space and safe return to earth, scientist felt optimistic about a manned flight. Apollo’s mission was geared towards completing two goals: First it aimed to reaching the moon before its global competitor the Soviet Union. Second it was to test the command module (CM) systems space-worthiness of send humans to the Moon and returning them safely to earth. The concept of multi-staging rocket proven in Saturn V convinced engineers Apollo 1 was ready human flight into space. The Tragedy On January 27, 1967 the crew were preparing for a preflight launch simulation; the purpose of this exercise was to ascertain whether the launch vehicle could function on internal power alone; this test was called "plugs out." At 1:00 P.M. the crew entered the capsule; the hatch was sealed at 2:50 P.M. and the capsule was pressurized to 16.2 pounds per square inch using 100% oxygen. The astronauts and the 1000 member launch crew ran simulation tests and continued the countdown for about three hours. The communications between mission control and the astronauts was really poor. Frustration was mounting as the astronauts tried to continue the test. At 6 P.M. the craft finally switched over to internal power. At T minus ten minutes a hold was called to check the environmental control system and electrical equipment. Just before 6:31 P.M. the telemetry showed an electrical surge. Unknown to anyone, a short in the CM had occurred beneath Grissom's seat and started a spark, which in a pressurized 100% oxygen atmosphere became a blowtorch. Chaffee announced almost casually over the intercom, "Fire. I smell fire." Five seconds later Grissom transmitted, "Fire! We've got a fire in the Cockpit!" at 6:31:16.8 the last words came from Chaffee: "We've got a bad fire! Let's get out! We're burning up!" During this transmission the cabin's belly split open; the fire had become an inescapable inferno. Three North American employees tried valiantly to reach the astronauts, but it was too late; three courageous and dedicated astronauts were dead. [3] The Reason After a thorough report and investigation conducted by North American Aviation and NASA Review Board, the contributions as well as the cause of the accident were as follows: 1. Deficiencies existed in Command Module design, workmanship and quality control. 2. The Command
Module contained many types and classes of combustible
material in 3. The rapid spread
of fire caused an increase in pressure and temperature
which 4. Due to internal
pressure, the Command Module inner hatch could not be
opened 5. The overall
communications system was unsatisfactory between
contractor and 6. Problems of
program management and relationships between Centers and
with the 7. Emergency fire, rescue and medical teams were not in attendance 8. The Command
Module Environmental Control System design provides a
pure oxygen
The
Space Shuttle Challenger Accident The Mission The goal of the 80's was initially to establish a Shuttle to Space Command followed by Star Wars and eventually the launch of the Space Station within the decade. Space transportation was essential to completing any of the tasks and having one capable of transporting humans to and from space was ideal. The concept of the shuttle was introduced since it was a fleet of reusable winged spaceship promising the most economical method to accessing space. The Challenger was designed to achieve the mission objectives of deploying a Tracking Data Relay Satellite and flying of Shuttle-Pointed Tool for Astronomy (SPARTAN-203)/Haley’s Comet Experiment Deployable. A free-flying module designed to observe tail and coma of Haley’s comet with two ultraviolet spectrometers and two cameras. Other objectives were Fluid Dynamics Experiment; Comet Haley Active Monitoring Program; Phase Partitioning Experiment; three Shuttle Student Involvement Program experiments; and set of lessons for Teacher in Space Project. These were the major [scientific] quest to develop and deploy of the Challenger. The Disaster On January 28th 1986 11:38EST the unraveling of a costly spectacular firework was underway. At 0.678 seconds after lift off of the space shuttle Challenger, NASA noticed a strong puff of gray smoke spurting from the vicinity aft of the field joint circumference, between 270 to 310-degrees on the right of the Solid Rocket Booster (SRB). Conformed by land and space cameras, vaporized material streaming from the joint indicated the joint was not sealed. At 2.73 seconds a black dense smoke appeared, the hot propellant gases were deteriorating the joint insulation and rubber O-ring in the seal. At 59.26 seconds telemetry showed pressure differential between the chamber and pressure pressures in the right and left boosters. The right booster chamber pressure was lower, resulting from a leak in the ruptured joint. At 64.66 seconds an abrupt change in flame and smoke plume conformed there was significant pressure loss due to a liquid hydrogen leak. At 73.12 seconds circumferential white vapor bloomed from the side of the tank causing severe structural failure to the SRB. The massive release of liquid hydrogen exerted a sudden thrust of 2.8 million pounds, pushing the booster faster and further apart from the shuttle. Within milliseconds, the inevitable happened at Mach 1.92 when the Challenger was engulfed in an explosive burn as the hypergolic fuel tanks ruptured and ignited into a reddish brown smoke plume. The Reason Outline in the
Presidential Report, the view of the findings that led to
the crash were as follows: The Commission concluded that
the cause of the Challenger accident was the failure of
the pressure seal in the aft field joint of the right
Solid Rocket Booster. The failure was due to a faulty
design unacceptably sensitive to a number of factors.
These factors were the effects of temperature, physical
dimensions, characteristics of material, the effects of
reusability, processing and the reaction of the joint to
dynamic loading. The decision to launch the Challenger
was flawed. Those who made the decision were unaware of
the recent history of problems concerning the O-rings and
the joint interaction. They were also unaware of the
initial written recommendation of the contractor Morton
Thiokol Inc. advising against the launch at temperatures
below 53 degrees Fahrenheit. They also did not have a
clear understanding of Rockwell’s concern that it
was not safe to launch because of ice on the pad. If the
decision-makers had known all of the facts, it is highly
unlikely that they would have decided to launch the
Challenger on January 28, 1986. [5]
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