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Challenger Essay Research Paper It was a (стр. 1 из 2)

Challenger Essay, Research Paper

It was a cold, crisp, and damp morning on the Florida Space Coast as the space shuttle Challenger raced through the sky at speeds approaching mach 2 at an altitude of 104,000 feet when something went perilously wrong. All of America watched, including the family members of the seven doomed crew members, as Challenger exploded into an expansive ball of fire, smoke and steam. An “Oh. . . no!” came as the crew?s final utterance from the shuttle as the orbiter broke-up. As the reality of what she was seeing became apparent, Pilot Michael John Smith?s daughter, 9 year old Erin Smith, could be heard yelling, “Daddy! Daddy! I want you, Daddy! You promised nothing would happen!” Unfortunately, the events of that tragic day could have been easily prevented. Weather had been the main cause for five delays during the last month. The launch had been carried out in spite on the fact that weather was the worst it had ever been in NASA?s history of manned space flight. With so many !

delays encountered in that twenty-fifth shuttle mission, NASA had become careless in getting Challenger on its way. As Challenger sat on the pad awaiting it?s ill-fated mission, there were signs that there was something wrong with the Right hand SRB (Solid Rocket Booster). Nevertheless these signs were ignored by a neglectful staff whose only concern was scheduling and not safety. Also, at the time of the accident, for purely monetary reasons, the shuttle had not been fitted with a means of escape for the crew in the case of an emergency; a fact not revealed until after the accident. Though the Space shuttle was the cutting edge of technology at the time, new advancements in technology make the Space Shuttle old, unsafe, inefficient, and not cost effective. However, because of cut backs in funding, NASA is unable to make any advancements in it?s technology to prevent another catastrophic accident for the space program. Also as a result of the cut backs, NASA has had tro!

uble keeping the existing space shuttles? hardware kept up. The effects of the accident were numerous; the space program was shut down for three years. Also the effects on the NASA staff were immense, leaving a feeling of guilt and fear. On January 28, 1986, the space shuttle Challenger and it?s crew embarked on a mission to broaden educational horizons and promote the advancement of scientific knowledge; their mission was cut short in one of the most tragic and most easily prevented tragedies in America?s history in space.

Before the accident, the 51-L (This mission?s assigned number) mission was supposed to be remembered for many reasons. One reason was that this was to be the twenty-fifth space shuttle mission. Another reason was that this was to be the first shuttle launch from pad 39-b which hadn?t been used since the Apollo missions. However, The major reason was this was to be the first crew to include a civilian member. Sharon Chista McAuliffe was chosen from a pool of 11,400 applicants. McAuliffe, 37, was a social studies teacher in Concord High School in New Hampshire. While in space, she planned to still teach two lessons entitled, “Where we?ve been, where we?re going, why?”, to her class. Then, at T plus 1:13, the mission and its crew became remembered for other, more disastrous reasons. An O-ring in the right SRB shattered in the extreme cold and began allowing liquid hydrogen to leak then explode incinerating the seven crew members, destroying the valuable payload, and bring!

ing the space program to a halt for nearly three years. America listened a long ten seconds before “?the commentary was resumed in a tense monotone”(Lewis, p21);

“Flight Controllers are looking very carefully at the situation. Obviously a major malfunction. We have no downlink. We have a report from the flight dynamics officer that the vehicle has exploded. The flight director confirms that. We are looking at checking with recovery forces to see what can be done at this point. Contingency procedures are in effect. We will report more as we have information available?”(Lewis, p21)

“Major Malfunction”, a phrase that stuck with everyone watching the launch that day. Although later, flight commentator Nesbit would be commended for remaining calm by some people, many people described the statement as “the understatement of the century”.

Following all the delays caused by the weather over the past five days, the launch was rescheduled for the morning of January, 28th. A cold front with high winds was forecasted to pass through east central Florida. However, the winds were expected to die down, and the morning was expected to be clear but very cold. Temperatures were expected to fall into the low twenties, a rarity for the sub-tropical Florida climate. “Mission managers for NASA assessed the possible effects of the cold weather on the launch, but the only threat they perceived to the launch safety was the ice on the pad structure?Ice breaking off the structure during launch could damage Challenger?s heat shield.”(Lewis, p4) Ice inspection teams visited the launch pad three times on the morning of the 28th. Their job was to find any debris that might be blown out by engine exhaust. They found a layer of ice ranging from one-eighth to three inches thick on the launch pad caused from allowing water to dribb!

le to prevent the pipes from freezing. Similar ice problems had prevented the space shuttle Discovery from being launched a year earlier, regardless of that, the Challenger was allowed to proceed with the launch. Weather conditions for this launch were the worst in NASA?s history of manned space flight. However, the weather was a concern for more than one reason. Separate from the problem the ice posed for the launch; the cold would prove to be a concern for the O-rings in the SRBs, holding back the extremely flammable liquid hydrogen. “The night before liftoff , engineer Roger Boisjoly had implored his supervisors at Martin Thiokol – the Utah company that made the solid rockets that boost the shuttle into orbit- to recommend that NASA delay the launch. The cold, he said — temperatures would fall to 27 degrees that night – might effect the rubber O-ring seals, thus allowing exhaust gasses to leak from the rocket joints. If that happened he said, Challenger could explod!

e on the launch pad. But Mission 51-L – America?s 53rd manned space flight – lifted off without a hitch, riding a shaft of fire toward orbit seven minutes away. In Morton Thiokol?s conference room, Boisjoly turned away from the TV and remarked quietly to a fellow engineer Bob Ebeling, “Well, we dodged the bullet on that one”?Seconds later Boisjoly was fighting back tears. He struggled back into his office, staring at the walls, his mind blurred by images and the contrail of smoke and steam stretched across the sky.”(Lamb, p1) The O-rings were made of materials called elastomers. Elastomers have several problems. When they get hot, they become gummy and sticky, and when they become cold they become brittle, as in the case of the Challenger. During the investigations an experiment showed how brittle the O-rings would have been. A piece of the same type of O-rings used in Challenger was placed in a glass of ice water for a few minutes. Upon being removed from the water, i!

t was gently tapped on the table top. The O-ring shattered into pieces. The O-ring used in the experiment was still 5-10 degrees warmer than the actual O-rings in the Space shuttle. The slight tap given to the O-ring in the experiment would have been nothing compared the vibrations encountered in rockets propelling a 40 ton Space Shuttle though the atmosphere at 1,400 miles per hour. In the end the negligent thinking of the weather and the O-rings that proved ultimately catastrophic for the Challenger and it?s crew.

There was great political pressure on NASA officials to launch Challenger as early as possible after a month of frustrating delays. It was rumored that the administration was anxious to have challenger in orbit by February 4th when President Regan was due to deliver his State of the Union message. It was suggested that plans had been made for a live communications hookup with challenger during the broadcast of the message. Scheduling was also tight because the space agency had scheduled 15 launches for 1986, compared with only 9 in 1985. Then 19 missions were planned for 1987. The delays in the launch of Challenger, and before that Columbia, were threatening to disrupt the schedule for the next two years. The dominant source of pressure to get the Challenger off the launch pad was Jupiter, the target of two scientific spacecrafts, Galileo and Ulysses, to be launched in the spring of 1986 in order to hit the planet with minimum energy trajectory. If the probes missed !

their window, it would not return until July 1987. All this put great pressure on NASA to make the fatal decision to forgo safety in exchange for scheduling.

As Challenger began its accent, there were many warning signs ignored that would have prompted immediate abortion of the launch. Before the shuttle even made it off the launch pad, two black plumes of smoke were visible on the side of the SRB, but it went unnoticed. Those two black plumes burned at a temperature of 5,600 degrees, burning a hole through the half-inch steel case holding the liquid hydrogen and allowing it to leak through the O-rings being shattered by the cold and vibrations of the rocket boosters. Engineers noticed the smoke but did not acknowledge fact that anything could go so seriously wrong, and passed it off as unrelated anomaly. Then again at 59 seconds into launch, 14 seconds before the explosion, there were eight giant bursts of flame originating from the SRB that also went ignored. Following that at 1 minute into launch pressure began to rapidly fall in the right-hand booster, showing a possible leak, by this point the explosion was too large and!

the shuttle was enveloped in flame. Now all NASA could do was watch as the shuttle was destroyed. It was not until weeks later that an investigation team realized how easily it could have been prevented. Because NASA was so preoccupied with getting up to schedule, no one was looking for any signs of failure.

“Beyond the pall of smoke and descending wreckage a lone parachute appeared, drifting casually down toward the sea. It was the 54 foot drogue in a parachute decent system of one booster, a system designed for the recovery of the boosters at sea. Highly visible against the dark blue of the sky, the parachute, still attached to the forward section, or frustum, of the booster, led hundreds of watchers to hope that the crew was drifting down to safety and would soon be rescued. The lack of such a launch escape system on the orbiter was not popularly known.” (Lewis p21) It was suggested that a escape system be included in the proposed replacement shuttle, but it was met with opposition for not being feasible. However, an escape system could be put in without too much trouble. The Saturn 5 rocket had a escape system; if an explosion impeded the crew module would be pushed to an altitude of 3,000 feet above the rocket and then land in the ocean with the parachutes used for re-e!

ntry. In a shuttle, however, if one were to try and go out the top window they would hit the high vertical tail and get sliced in half. If one were to try and go out the side window they would hit the wings ending in the same fate. The escape window would have to be pretty narrow. The crew would only be able to escape the shuttle without any equipment except their helmet, flight suit, and a parachute. Even as crude a system as it is, it could have saved the lives of the crew of Challenger from their fiery death.

An advisory committee came to the conclusion that our space program is too reliant on the Space Shuttle for access to space. “The panel noted that the vehicle tends to be complex with limited margins; it has not realized the promised cost savings; and should it fail catastrophically it takes with it a substantial portion of the nation?s future manned launch capability and, potentially several human lives.”(Worsnop, p1) Government funding cut backs have cast doubt on NASA?s ability to keep up it?s four shuttle fleet. “NASA personnel found cracks in the hinges of the two doors on the shuttle?s underside that are supposed to close when the external fuel tank drops away minutes after liftoff. If the doors do not form a tight seal after closing, the vehicle could be destroyed when it re-enters the Earth?s atmosphere at the end of the mission.” (Worsnop, p1) The Space Shuttle, once regarded as the cutting edge of technology, is becoming obsolete. The Congressional Office of T!

echnology Assessment noted that the shuttle?s obsolescence has many aspects to it. After a certain amount of flights, metal fatigue makes the shuttle unsafe. Also, replacement parts for the shuttle may no longer be manufactured. “NASA engineers are particularly worried about another problem, like that which caused the Challenger accident, occurring in one of the other shuttles.”(Patrick, p1) “With the system and the risks involved, there will be an accident again someday. 35 years of space flight had proven to be more expensive and more dangerous than it is worth.”(Price, p1) After the Challenger accident the odds of another accident was put up to 1 in 78. Now a more recent calculation put the risk at 1 in 248. Yet, these are the same people who told us the rate was 1 in 100,000. Such considerations lead the panel to propose that the shuttle be gradually taken out of service. The transition period will be over many years, but some of the burden being carried by the spa!

ce shuttle will begin to decrease immediately. There have been over 280 first time anomalies in the space shuttle in the past year alone. NASA has had to resort to “cannibalizing” components from one shuttle to another. Though the shuttle was once state-of-the-art technology nearly 20 years ago, now its technology is becoming obsolete.

As a result of the space shuttle Challenger disaster, the space program was halted for three years as NASA research teams searched for the cause of the terrible disaster. Previously assembled shuttle components were taken apart a piece at a time and searched millimeter by millimeter for any imperfections. Every frame of video, taken from every angle were analyzed. Every byte of computer records were scrutinized. “Mr. O?Connor – who flew on the shuttle Atlantis three months before Challenger was destroyed – said his next mission wasn?t until 1991.” (Price, p1) But there more to the effects than the investigations; there were also many emotional issues that had to be faced. “For the Challenger mission, Robert B. Sieck was Director of shuttle operations at Florida?s Kennedy Space Center – a position he still holds. He is also 57, balding and soft spoken. On the wall of his second floor office is a formal portrait of the Challenger Crew, autographed by the seven members. !

There is also a quote from Teddy Roosevelt that he hung after the explosion. It says ” the credit belongs to the man who spends himself in a worthy cause; and if he fails, at least he?ll never be with those cold and timid souls who know neither victory nor it?s pursuit.” “There was a high level of schedule pressure.”(Lamb, p1) When asked “How fast did you get to wondering if it was you fault?” he replied, “Pretty quickly. The hardest thing for me to overcome was my guilt. Although a review showed that nobody at Kennedy Space Center was to blame, we were all members of the team that allowed a launch to occur that shouldn?t have occurred. There is a feeling that is was our fault, and some still carry that today.”

There were many ways that the challenger accident could have been prevented. The cold weather and it?s interaction with the O-rings was the main cause of the Accident. The shuttle should never have been allowed to be launched in that kind of weather. If the program hadn?t been so rushed, the staff would?ve been able to more carefully examine the reality of launching a shuttle in that weather. Even after the shuttle?s launch was started, there were numerous signs on what was to happen. However, these signs were neglected by a tense, rushed staff, and nothing was caught in time. If everything had happened the way it did, the crew could still be alive if some sort of escape system had been installed. The crew might have had enough time to escape be for the explosion enveloped their shuttle. As the Space shuttle program approaches 20 years in service, the technology is becoming more and more out of date. The shuttles have become old and unsafe, and a new program will soo!

n have to take their place. On January 28, 1986, the space shuttle Challenger and it?s crew embarked on a mission to broaden educational horizons and promote the advancement of scientific knowledge; their mission was cut short in one of the most tragic and most easily prevented tragedies in America?s history in space.

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S2 : The Causes of the Scientific Revolution

Science, in it?s simplest forms, emerged about five millennia ago. Then in around the second century the accumulation of wealth and leisure brought about the introduction of curiosity and science began to make small advancements. Aristotle, a famous Greek scientist and philosopher, believed that the cosmos was based on the notion of an enclosed universe consisting of concentric, crystalline, spheres revolving around a stationary Earth. This “Geocentric” universe was the basis for both the Roman and Greek sciences. Then through the Middle Ages and the Renaissance the public?s concern turned immensely to the Christian church which remained essentially ambivalent the Greek and Roman sciences and philosophies. Thus little if no interest was paid to the sciences. The devotion to the RCC (Roman Catholic Church) brought along with it a massive scientific regression that would last for hundreds of years. Then, seven centuries later the Reformation, the immense movement away fr!