Brief introduction of American space shuttle accident.

1986 65438+1On October 28th, there was no cloud in Wan Li over Cape Canaveral. In the stands 6.4 kilometers away from the launch site, more than 1000 spectators gathered, including 19 middle school students who came to watch the space shuttle launch and see off their beloved teacher mcauliffe. 1984, NASA announced that it would invite a teacher to take part in space flight, and planned to give two popular science classes on space and flight to primary and middle school students in China. Students can also ask mcauliffe questions through the special line. Mcauliffe was carefully selected from more than 1 1000 teachers. When the children saw the spectacular scene of the space shuttle carrying their teacher into space, they blew horns and beat drums with excitement.

The space shuttle challenger is rising steadily: after 7 seconds, the plane turns over; 16 seconds, with the fuselage back to the ground and the belly facing the sky to complete the angle transformation; At 24 seconds, the thrust of the main engine drops to 94% of the predetermined power; At 42 seconds, the main engine was reduced to 65% of the predetermined power as planned to avoid the disintegration of the space shuttle due to overheating of the shell when passing through the high-altitude turbulence zone. At this time, everything is normal, the speed has reached 677 meters per second and the height is 8000 meters. At 50 seconds, a trace of white smoke was found on the ground from the side of the solid booster on the right side of the space shuttle, which did not attract people's attention. At 52 seconds, the ground command center informed the commander Scobie to restore the engine to full speed. 59 seconds, altitude 10000 meters, the main engine has been working at full speed, and the booster has burned nearly 450 tons of solid fuel. At this time, the data displayed by the ground control center and the computer on the space shuttle have not been abnormal. At 65 seconds, Scobie reported to the ground that "the main engine has been increased" and "Understood, full speed ahead" was the last report word received by the ground monitoring and control center. In the 73rd second, at an altitude of 16600 meters, the space shuttle suddenly flashed a bright light, the external fuel tank exploded in the air, and the space shuttle was blown to pieces. The explosion of Challenger, the communication with the ground, was suddenly interrupted after 73 seconds of liftoff, and all the data on the screen of the monitoring center suddenly disappeared. Challenger became a fire, and two out-of-control solid booster rockets broke away from the fireball and flew forward in a V shape, which was in danger of falling into a densely populated area. Billinger, the safety officer in charge of the Space Center, had a keen eye and detonated them with a remote control device at the100th second.

Challenger is wrecked! After the explosion, debris was scattered 30 kilometers southeast of the launch 1 hour, and the space shuttle with a value of10.2 billion dollars disappeared instantly, killing all seven crew members. The whole world was shocked by this, and leaders of various countries called to express their condolences. However, while people are grieving, their unremitting pursuit of science has not stopped. Gleason, who died in the fire of Apollo 1 experimental spacecraft, once said a touching sentence: "If we die, everyone should treat it as an ordinary thing. We are engaged in an adventurous career. In case of accidents, don't delay the progress of the plan. Conquering space is worth the risk. "

The cause of the accident was finally found out:

When launching, the air temperature was too low, and the launch platform froze, which led to the hardening and failure of the O-ring that fixed the right auxiliary fuel tank. When igniting, the flame burns from top to bottom, and the O-ring needs to expand in time, but the O-ring has failed, and the flame is ejected outward, emitting black smoke intermittently. However, due to the addition of aluminum in the fuel, the aluminum slag formed by combustion blocked the crack and temporarily replaced the sealing function of O-ring before the open flame rushed out of the crack.

Ten seconds before the explosion, the space shuttle was hit by a powerful airflow, which was as powerful as Hurricane Katrina. There is an unusual "z" at the end of the condensate. The next vibration caused the aluminum slag to fall off, clearing the last barrier to prevent the open flame from leaking from the joint, and the flame sprayed on the main fuel tank.

One second before the explosion, the flame combustion caused the O-ring of the main fuel tank to fall off, which caused the bottom of the main fuel tank to fall off. The shuttle's nose also hit the top of the main fuel tank. Seventy-three seconds after launch, Challenger exploded thousands of pieces with 40,000 liters of fuel.

In fact, the accident could have been avoided. Before the launch 13 hours, an important engineer held a conference call with the company's superiors, pointing out that Challenger's last launch was almost destroyed by O-ring failure, but the superiors reserved their views because they were eager to complete fast and cheap space travel. 30 minutes before launch, a Boeing 757 passenger plane reported strong airflow, but the launch center did not pay attention to it. therefore ...

The seven victims of the space hero monument accident let us always remember the names of the seven brave men who died for the cause of science on the Challenger. They are: Captain: Francis Scobie, 46 years old; Pilot: michael smith, 40 years old, astronaut: Judian resnick (female), 36 years old; Ronald mcnair, 35 years old; Ellison Oni Tsuka, 39; Gregory jervis, 4 1 year; Teacher Christa McAuliffe (female), 37 years old.

Captain Francis Scobie used to be a fighter pilot of the US Air Force and later became a test pilot of advanced aircraft. He has been dealing with danger all his life. He is humorous and cheerful, and has become the core and soul of the whole unit.

The pilot's name is michael smith, and he served in the US Navy as a fighter pilot. He won many medals, including the Navy Super Flying Cross and the National Silver Star Cross for daring to fight.

Astronaut Judith Resnik likes to play the piano in her spare time and find beauty in music. Judith likes to smile, which is full of confidence in her career and life.

Ronald mcnair, an astronaut from southern California, honed his strong character through his work in cotton fields. He dreams of living in an outer space station and doing experiments in weightless space: playing saxophone.

Gregory Jarvis took part in this space trip with great hope. He brought a small flag as a souvenir from his alma mater, University of new york at Buffalo. He wants to take this flag to explore space.

Ellison Oni Tsuka (Oni Tsuka Cheng Er; Ellison Onizuka was born in Hawaii, and his ancestral home is Japanese. When he was a child, he always ran around barefoot in the coffee fields and the cemetery of Macdamia. He has always dreamed of traveling to the moon one day. After becoming a pilot, he is ambitious to make great achievements.

Christa McAuliffe was born in Boston, USA, and teaches at Concord Middle School in New Hampshire. She is a famous sociology teacher, married and has a son and a daughter. According to the plan, she will teach two space classes to more than 2.5 million primary and secondary school students in the United States and Canada through television in space, and will also participate in many scientific performances on the space shuttle, and show them to students after the video, becoming the first "space teacher" in the world.

After the astronauts were killed, President Reagan made many speeches to commemorate these outstanding "challengers".

Columbia

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The American space shuttle Columbia, with seven astronauts on board, returned to Earth after completing the 16-day space mission, but an accident occurred before landing, and the space shuttle disintegrated and crashed. Columbia suddenly disappeared from radar 16 minutes before landing. Television images show that the disintegrated Columbia has drawn several white tracks over Texas. NASA did not immediately announce that the crew, including an Israeli astronaut, were killed, but the flag at Kennedy Airport was lowered at half mast. At present, the search for the wreckage of Columbia in Texas continues, and NASA has warned people not to touch any debris because the engine of the space shuttle is covered with highly toxic chemical paint. There is no possibility of Columbia flying to a forced landing. "In this case, I'm afraid Columbia has no choice," NASA spokesman Keller Helian told CNN. After the incident, President Bush immediately ended his short vacation at Camp David and returned to the White House to pay close attention to the further development of the situation. Columbia is the longest-serving of the four existing space shuttles in the United States. This accident is reminiscent of the crash of Challenger 19861October 28th, when all seven astronauts on board were killed. Angela Bell, a spokeswoman for the FBI, said there was no direct evidence that the incident was related to terrorists. Columbia was flying at an altitude of 203,000 feet at a speed of 65,438+02,500 miles per hour. Katherine Watson, a spokeswoman for NASA, told NBC: "At present, all flight controllers are trying to find data that can explain what happened." But when asked if any astronauts could survive, Watson shed tears. The seven astronauts killed on Columbia were Rick Herzburn, William McCool, michael anderson, david brown, Kelpana Jorah, Laurel Clark and Israeli Ilan Ramon. Israeli Prime Minister Sharon said: "This incident is a great tragedy for the two governments, the two peoples and the families of the astronauts who died." On June 28th, 2006, at 10 am EDT, the Kennedy Space Center in Florida, USA, held an event to commemorate three American space disasters and pay tribute to the seven astronauts who died. Three space disasters in the United States were concentrated in1Apollo on October 27th, Challenger in 65438 and Colombia on February 28th.

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Accident process

A piece of foam that fell off the fuel tank shortly after the launch of the American space shuttle Columbia has always been a big doubt in the accident investigation. An analysis report released by NASA shows that the space shuttle may be hit by as many as three bubbles instead of one as previously thought. The space shuttle Columbia was launched on June+10/October 16, 65438. 1October 24+65438, the technical staff of Boeing Company, the contractor of the space shuttle project, wrote this report and submitted it to the flight control department of NASA on1October 27+65438. According to the report, 82 seconds after the launch of Columbia, three pieces of foam, each about 20 inches (50 cm) long, fell off from the support area connecting the external fuel tank and the space shuttle. After hitting the space shuttle, they "seemed to disintegrate" and became many smaller pieces. In publishing this report, NASA stressed that according to the conclusion of the report, the impact of foam debris will not affect the flight safety of the space shuttle, and the flight control department of NASA also "agrees with this conclusion". Nevertheless, after the publication of the new report, the impact of foam materials on the "Columbia" accident once again attracted people's attention. 1 The problem of foam fragments surfaced shortly after the disintegration and crash of Columbia in February. Although NASA has always insisted that the impact of foam fragments will not cause serious consequences, the independent Committee responsible for investigating the "Columbia" accident is still conducting in-depth analysis of the impact of foam fragments. At present, the main conclusion of this independent investigation Committee is that there may be loopholes in the shell of Columbia, which may lead to ultra-high temperature gas entering the space shuttle and eventually lead to an accident. According to the document published by NASA 2 1, an engineer of NASA warned in an e-mail on1October 29th that the damage of the external thermal insulation tile of the space shuttle may lead to cracks in the wheel compartment or landing gear door.

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astronaut

Captain Rick Harzband, male, 45 years old, former Lieutenant Colonel Air Force, Texan. 1994 Become an astronaut.

William mccullough, male, 4 1 year old, former navy commander, father of three children. 1996 Become an astronaut.

Michael anderson, male, 43 years old, was born into a military family and became one of the few black astronauts from 65438 to 0994.

Kispana chawla, female, 4 1 year old, immigrated to the United States from India in 1980s, and became an astronaut in 1994.

David brown, male, 46 years old, became an astronaut from 65438 to 0996.

Laurel Clark, female, 4 1 year old, former naval doctor, 1996 became an astronaut.

Ilan Ramon, male, 48 years old, is a Lieutenant Colonel of the Israeli Air Force. 1997 became Israel's first astronaut.