The Tragic Challanger Explosion

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The Tragic Challanger Explosion Essay, Research Paper

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.

“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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