The Tragic Challenger Explosion

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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.

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