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The Tragic Challenger Explosion Essay, Research Paper
The Tragic Challenger Explosion
The Tragic Challenger Explosion Space Travel. It is a sense of national pride
for many Americans. If you ask anyone who was alive at the time, they could
probably tell you exactly where they were when they heard that Neil Armstrong
was the first person to walk on the Moon. But all of the success in our space
programs is overshadowed by tragedy. On January 28, 1986, one of the worst
disasters in our space program’s history occurred. Many people were watching at
the moment because it was the highly televised space mission where, for the
first time, a civilian was a member of the crew that was to be shot into space.
This civilian was the winner of the “Teacher in Space” contest, Christa
McAuliffe. The disaster: the explosion of the Space Shuttle Challenger.
(Compton’s 1) Many people thought that disaster couldn’t strike because a
civilian was on board. But as the whole nation found out, nobody is immortal.
By examining this further, we will look at the lives of the seven who died in
this dumbfounding calamity, take a look at exactly what went wrong during this
fateful mission, and the outcome from this sorrowful occurrence. First, who
exactly were those astronauts that died on the Challenger? Sharon Christa
Corrigan McAuliffe, born in 1948, was the famous winner of the teacher-in-space
program, was a high school teacher at Concord, N. H., a wife, and a mother of
two children. She touched the lives of all those she knew and taught. As a
school official in Concord said after her death, “To us, she seemed average.
But she turned out to be remarkable. She handled success so beautifully.” She
also wanted everyone to learn more, including herself. Demonstrating her
aspirations after entering the space program, she is quoted saying, “What are we
doing here? We’re reaching for the stars.” Also, after reflecting on her
position, she said in August 1995, “I touch the future, I teach (Gray 32).”
Francis R. (Dick) Scobee, born in 1948, was a tremendous enthusiast for aviation
and the space program. At 18 years old, he enlisted in the Air Force. While
working as a mechanic in the service, he put himself through night school,
eventually earning a degree in aerospace engineering that helped him become an
officer and a pilot. He loved flying. Scobee once observed, :You know, it’s a
real crime to be paid for a job that I have so much fun doing.” On one of his
space missions, he carried a banner made for him by students at Auburn High, his
old high school. It read “TROJANS FLY HIGH WITH SCOBEE.” School officials
announced after the tragic explosion that the banner would be put on display to
remind others at Auburn High that other seemingly ordinary students can too fly
high. (Gray 33) Judith Resnik, born 1949, had a Ph.D. in electrical engineering.
She was very ambitious and loved everything. She once said, “I want to do
everything there is to be done.” Being chosen for the space program gave her
the opportunity to meet a few self-described personal goals: “To learn a lot
about quite a number of different technologies; to be able to use them somehow,
to do something that required a concerted team effort and, finally, a great
individual effort (Gray 33).” She had said once, when asked, about the dangers
of the space program, “I think something is only dangerous if you are not
prepared for it or if you don’t have control over it or if you can’t think
through how to get yourself out of a problem.” For Resnik, danger was simply
another unknown to be mastered. Ronald McNair, born in 1950, was the second
black man in space. He was truly remarkable growing up in his segregated South
Carolina school. He was remembered by those he knew as “one who was always
looking to the clouds.” Jesse Jackson, one of his collage classmate’s at N.C.
Agricultural and Technical State University said McNair saw participation in the
space program as “the highest way he could contribute to the system that gave
him so much.” McNair did think much of the space program. He once said, “The
true courage of space flight comes from enduring . . . persevering and believing
in oneself (page 34).” Michael Smith, born in 1945, always had his head in the
clouds. At the age of 16, he soloed in a single-engine Aeronca. After the U.S.
put its first astronaut into space in 1961, Smith decided that was where he
wanted to be. His older brother said, “In high school he paid a lot of
attention to academics because he knew that was the best way to get in.” He
also thought much of the space program. He once said, “Everybody looks at
flying the shuttle as something dangerous. But it’s not. It’s a good program,
and something the country should be proud of (Gray 34).” Ellison Onizuka, born
in 1946, became an instant hero to both the Hawaiians and the Japanese Americans
because he was the first member of either group to fly in space. He was one who
was always fascinated by the vastness of outer space and spend a lot of time
studying it. When he was young, he spent much of his time examining the
universe through a telescope at Honolulu’s Bishop Museum. He also said before
the Challenger launch, “I’ll be looking at Halley’s comet. They tell me I’ll
have on of the best views around (Gray 35).” His family always looked favorably
upon his achievement. After the tragedy, his mother remembered that “Ellison
always had it in his mind to become an astronaut, but was too embarrassed to
tell anyone. When he was growing up, there were no Asian astronauts, no black
astronauts, just white ones (Gray 35).” Ellison will be forever remembered as
being the first Japanese American in space. Finally, the last member of the
seven person crew, Gregory Jarvis, born in 1944. Gregory was very dedicated to
the space program. Despite being bumped off two previous flights, he finally
got his chance. Unfortunately, his only flight was that of the Challenger. It
is very saddening to see seven bright lives vanish in a ball of fire, but it is
said that the explosion was so rapid that the crew did not realize their coming
fate. (Gray 35) Perhaps we can all take comfort in the fact that their last
vision was that of the stars. Now, many people haven’t heard exactly what went
wrong to cause such an explosion. (Dumoulin, 1-2) The Challenger finally
launched after five days of delays. On January 28, 1986, the morning of the
launch, there was ice at Kennedy Space Center. After an inspection crew gave
the go-ahead, the launch was underway. Just after liftoff at .678 seconds into
the flight, photographic data show a strong puff of gray smoke was spurting from
the vicinity of the aft field joint on the right solid rocket booster. Computer
graphic analysis of film from pad cameras indicated the initial smoke came from
the 270 to 310-degree sector of the circumference of the aft field joint of the
right solid rocket booster. This area of the solid booster faces the External
Tank. The vaporized material streaming from the joint indicated there was not
complete sealing action within the joint. Eight more distinctive puffs of
increasingly blacker smoke were recorded between .836 and 2.500 seconds. The
smoke appeared to puff upwards from the joint. While each smoke puff was being
left behind by the upward flight of the Shuttle, the next fresh puff could be
seen near the level of the joint. The multiple smoke puffs in this sequence
occurred at about four times per second, approximating the frequency of the
structural load dynamics and resultant joint flexing. As the Shuttle increased
its upward velocity, it flew past the emerging and expanding smoke puffs. The
last smoke was seen above the field joint at 2.733 seconds. The black color and
dense composition of the smoke puffs suggest that the grease, joint insulation
and rubber O-rings in the joint seal were being burned and eroded by the hot
propellant gases. At approximately 37 seconds, Challenger encountered the first
of several high-altitude wind shear conditions, which lasted until about 64
seconds. The wind shear created forces on the vehicle with relatively large
fluctuations. These were immediately sensed and countered by the guidance,
navigation and control system. The steering system (thrust vector control) of
the solid rocket booster responded to all commands and wind shear effects. The
wind shear caused the steering system to be more active than on any previous
flight. Both the Shuttle main engines and the solid rockets operated at reduced
thrust approaching and passing through the area of maximum dynamic pressure of
720 pounds per square foot. Main engines had been throttled up to 104 percent
thrust and the solid rocket boosters were increasing their thrust when the first
flickering flame appeared on the right solid rocket booster in the area of the
aft field joint. This first very small flame was detected on image enhanced film
at 58.788 seconds into the flight. It appeared to originate at about 305
degrees around the booster circumference at or near the aft field joint. One
film frame later from the same camera, the flame was visible without image
enhancement. It grew into a continuous, well-defined plume at 59.262 seconds. At
about the same time (60 seconds), telemetry showed a pressure differential
between the chamber pressures in the right and left boosters. The right booster
chamber pressure was lower, confirming the growing leak in the area of the field
joint. As the flame plume increased in size, it was deflected rearward by the
aerodynamic slipstream and circumferentially by the protruding structure of the
upper ring attaching the booster to the External Tank. These deflections
directed the flame plume onto the surface of the External Tank. This sequence of
flame spreading is confirmed by analysis of the recovered wreckage. The growing
flame also impinged on the strut attaching the solid rocket booster to the
External Tank. The first visual indication that swirling flame from the right
solid rocket booster breached the External Tank was at 64.660 seconds when there
was an abrupt change in the shape and color of the plume. This indicated that
it was mixing with leaking hydrogen from the External Tank. Telemetered changes
in the hydrogen tank pressurization confirmed the leak. Within 45 milliseconds
of the breach of the External Tank, a bright sustained glow developed on the
black-tiled underside of the Challenger between it and the External Tank.
Beginning at about 72 seconds, a series of events occurred extremely rapidly
that terminated the flight. Telemetered data indicate a wide variety of flight
system actions that support the visual evidence of the photos as the Shuttle
struggled futility against the forces that were destroying it. At about 72.20
seconds the lower strut linking the solid rocket booster and the External Tank
was severed or pulled away from the weakened hydrogen tank permitting the right
solid rocket booster to rotate around the upper attachment strut. This rotation
is indicated by divergent yaw and pitch rates between the left and right solid
rocket boosters. At 73.124 seconds,. a circumferential white vapor pattern was
observed blooming from the side of the External Tank bottom dome. This was the
beginning of the structural failure of hydrogen tank that culminated in the
entire aft dome dropping away. This released massive amounts of liquid hydrogen
from the tank and created a sudden forward thrust of about 2.8 million pounds,
pushing the hydrogen tank upward into the intertank structure. At about the same
time, the rotating right solid rocket booster impacted the intertank structure
and the lower part of the liquid oxygen tank. These structures failed at 73.137
seconds as evidenced by the white vapors appearing in the intertank region.
Within milliseconds there was massive, almost explosive, burning of the hydrogen
streaming from the failed tank bottom and liquid oxygen breach in the area of
the intertank. At this point in its trajectory, while traveling at a Mach number
of 1.92 at an altitude of 46,000 feet, the Challenger was totally enveloped in
the explosive burn. The Challenger’s reaction control system ruptured and a
hypergolic burn of its propellants occurred as it exited the oxygen-hydrogen
flames. The reddish brown colors of the hypergolic fuel burn are visible on the
edge of the main fireball. The Orbiter, under severe aerodynamic loads, broke
into several large sections which emerged from the fireball. Separate sections
that can be identified on film include the main engine/tail section with the
engines still burning, one wing of the Orbiter, and the forward fuselage
trailing a mass of umbilical lines pulled loose from the payload bay. The
Explosion 73 seconds after liftoff claimed crew and vehicle. Cause of explosion
was determined to be an O-ring failure in right solid rocket booster. Cold
weather was a contributing factor. Finally, what was the outcome of this
terrible disaster? (Compton’s, page 1) The shuttle program was suspended until
the exact cause could be found. It wasn’t until September 1988 when the next
shuttle launch happened. After many hours of investigating and finding out what
exactly caused the disaster, many changes were made to the structural designs of
the space shuttle. Also, they don’t allow launches when the temperature is that
low. Also, the explosion delayed the now famous Hubble Telescope program
(Church 38). We have seen the tremendous photographs the Telescope has sent to
Earth, it’s a shame they couldn’t have been received sooner. From a media
standpoint, this disaster really changed the way television was used to report
major disasters. It may seem fairly common when Special Reports interrupt
normal programming, but in 1986, it was pretty unusual. In fact, ABC
switchboards alone fielded more than 1,200 complaints from people who wanted to
watch soap operas rather than an all-day report about the Challenger and the
late breaking news related to it (Zoglin 42). Television definitely had a
tremendous impact on reporting this story. ABC Anchorman Peter Jennings said,
“We all shared in this experience in an instantaneous way because of television.
I can’t recall any time or crisis in history when television has had such an
impact. (Zoglin 42)” The disaster even affected President Reagan’s State of the
Union address. When asked about the State of the Union speech, Reagan replied,
“There could be no speech without mentioning this, but you can’t stop governing
the nation because of a tragedy of this kind (Magnuson 29).” In conclusion, it
is such a sad tragedy that this negligence led to such a disaster. If we learn
from our mistakes, then hopefully, this sort of disaster won’t happen again.
Works Cited “Space Shuttle Missions: Challenger.” Compton’s Encyclopedia of
American History on CD-ROM. Compton’s New Media, Inc., 1994.
Morrow, Lance. “A Nation Mourns.” Time 10 February 1986: 23.
Magnuson, Ed. “A Nation Mourns.” Time 10 February 1986: 24-31.
Gray, Paul. “Seven Who Flew for All of Us.” Time 10 February 1986: 32-35.
Friedrich, Otto. “Looking for What Went Wrong.” Time 10 February 1986: 36-37.
Church, George J. “Putting the Future on Hold.” Time 10 February 1986: 38-41.
Zoglin, Richard. “Covering the Awful Unexpected.” Time 10 February 1986: 42-
45. Murphy, Jamie. “It Was Not the First Time.” Time 10 February 1986: 45.
Dumoulin, Jim. “51-L” [Online] Available
http://www.ksc.nasa.gov/shuttle/missions/51-l/mission-51-l.html, October 5,
1996.
Annotated Bibliography “Space Shuttle Missions: Challenger.” Compton’s
Encyclopedia of American History on CD-ROM. Compton’s New Media, Inc.,
1994.
This article gave a nice overview of the incident, but didn’t really get
detailed. It helped me get a picture of what happened and what caused the
failure. This is a secondary source.
Morrow, Lance. “A Nation Mourns.” Time 10 February 1986: 23.
This article gave a nice portrayal of what people felt while watching
the launch on television. This is a secondary source.
Magnuson, Ed. “A Nation Mourns.” Time 10 February 1986: 24-31.
This article gave a good look at the National perspective of things
after the explosion. It also gave a good account of the memorial service. This
is a secondary source.
Gray, Paul. “Seven Who Flew for All of Us.” Time 10 February 1986: 32-35.
This article gave me most of my report. It gave a nice description of
the seven astronauts that died on the shuttle. This is a secondary source.
Friedrich, Otto. “Looking for What Went Wrong.” Time 10 February 1986: 36-
37.
This article gave an account of the theories that appeared afterwards
about why the shuttle exploded. It also told about the NASA press conference
held afterwards. This is a secondary source.
Church, George J. “Putting the Future on Hold.” Time 10 February 1986: 38-41.
This article told about the setbacks to the space program that the
explosion would cause. It mainly told about the Hubble space telescope. This
is a secondary source.
Zoglin, Richard. “Covering the Awful Unexpected.” Time 10 February 1986:
42-45.
This article went to the media’s perspective of covering the accident.
It told about how the three major networks (ABC, CBS, NBC) spend their time
covering the disaster. This is a secondary source.
Murphy, Jamie. “It Was Not the First Time.” Time 10 February 1986:
45.
This article told about previous disasters in the space programs of the
United States and Russia. This is a secondary source. Dumoulin, Jim. “51-L”
[Online] Available
http://www.ksc.nasa.gov/shuttle/missions/51-l/mission-51-l.html, October
5, 1996.
This article from NASA also contributed a lot to my report. It is the
official report about the Challenger explosion. This is a primary source.