Space shuttle crashes how many

Soyuz 1 was still in the experimental stage at the time of the mission, and problems began almost immediately after it entered orbit, some nine minutes after launch. Soyuz 11 — Eager to outstrip their counterparts in the U. That June, three cosmonauts aboard Soyuz 11 spent three weeks conducting experiments and observations at the space station, earning hero status back at home.

Upon their return trip on June 30, the spacecraft made a normal reentry and a perfect automatic landing. But when the ground team opened the hatch, they found all three cosmonauts unresponsive. A faulty air vent had opened when the orbital and descent modules of Soyuz 11 separated, and the cabin had depressurized; the cosmonauts, none of whom were wearing space suits, likely suffocated to death 30 minutes before landing.

As a legacy of the Soyuz 11 disaster, the Soviet and U. On January 28, , the tenth mission of the space shuttle Challenger ended in tragic disaster. Challenger — On the bitterly cold morning of January 28, , the space shuttle Challenger broke apart 73 seconds after its launch from Cape Canaveral, crashing into the Atlantic Ocean from an altitude of some 50, feet. The shuttle flight C of January 24, , was launched during some of the coldest weather in Florida history.

Upon examination of the booster joints, engineers at Thiokol noticed black soot and grease on the outside of the booster casing, caused by actual gas blow-by. This prompted Thiokol to study the effects of O-ring resiliency at low temperatures. They conducted laboratory tests of O-ring compression and resiliency between 50lF and lF. In July , Morton Thiokol ordered new steel billets which would be used for a redesigned case field joint.

At the time of the accident, these new billets were not ready for Thiokol, because they take many months to manufacture. This prompted Alan McDonald to ask his engineers at Thiokol to prepare a presentation on the effects of cold temperature on booster performance.

A teleconference was scheduled the evening before the re-scheduled launch in order to discuss the low temperature performance of the boosters. Boisjoly and another engineer, Arnie Thompson, knew this would be another opportunity to express their concerns about the boosters, but they had only a short time to prepare their data for the presentation.

Thiokol's engineers gave an hour-long presentation, presenting a convincing argument that the cold weather would exaggerate the problems of joint rotation and delayed O-ring seating.

After the technical presentation, Thiokol's Engineering Vice President Bob Lund presented the conclusions and recommendations.

The boosters had experienced O-ring erosion at this temperature. Marshall's Solid Rocket Booster Project Manager, Larry Mulloy, commented that the data was inconclusive and challenged the engineers' logic.

A heated debate went on for several minutes before Mulloy bypassed Lund and asked Joe Kilminster for his opinion. Kilminster was in management, although he had an extensive engineering background. By bypassing the engineers, Mulloy was calling for a middle-management decision, but Kilminster stood by his engineers. Several other managers at Marshall expressed their doubts about the recommendations, and finally Kilminster asked for a meeting off of the net, so Thiokol could review its data.

Boisjoly and Thompson tried to convince their senior managers to stay with their original decision not to launch. A senior executive at Thiokol, Jerald Mason, commented that a management decision was required. The managers seemed to believe the O-rings could be eroded up to one third of their diameter and still seat properly, regardless of the temperature. The data presented to them showed no correlation between temperature and the blow-by gasses which eroded the O-rings in previous missions.

According to testimony by Kilminster and Boisjoly, Mason finally turned to Bob Lund and said, "Take off your engineering hat and put on your management hat. The new recommendation stated that the cold was still a safety concern, but their people had found that the original data was indeed inconclusive and their "engineering assessment" was that launch was recommended, even though the engineers had no part in writing the new recommendation and refused to sign it.

NASA managers decided to approve the boosters for launch despite the fact that the predicted launch temperature was outside of their operational specifications. In order to keep the water pipes in the launch platform from freezing, safety showers and fire hoses had been turned on. Some of this water had accumulated, and ice had formed all over the platform.

There was some concern that the ice would fall off of the platform during launch and might damage the heat resistant tiles on the shuttle.

The ice inspection team thought the situation was of great concern, but the launch director decided to go ahead with the countdown. Note that safety limitations on low temperature launching had to be waived and authorized by key personnel several times during the final countdown. These key personnel were not aware of the teleconference about the solid rocket boosters that had taken place the night before. At launch, the impact of ignition broke loose a shower of ice from the launch platform.

Some of the ice struck the left-hand booster, and some ice was actually sucked into the booster nozzle itself by an aspiration effect. Although there was no evidence of any ice damage to the Orbiter itself, NASA analysis of the ice problem was wrong. The booster ignition transient started six hundredths of a second after the igniter fired. The booster's segmented steel casing ballooned and the joint rotated, expanding inward as it had on all other shuttle flights.

Eight hundredths of a second after ignition, the shuttle lifted off. Engineering cameras focused on the right-hand booster showed about nine smoke puffs coming from the booster aft field joint. Before the shuttle cleared the tower, oxides from the burnt propellant temporarily sealed the field joint before flames could escape.

Fifty-nine seconds into the flight, Challenger experienced the most violent wind shear ever encountered on a shuttle mission. The glassy oxides that sealed the field joint were shattered by the stresses of the wind shear, and within seconds flames from the field joint burned through the external fuel tank.

Hundreds of tons of propellant ignited, tearing apart the shuttle. One hundred seconds into the flight, the last bit of telemetry data was transmitted from the Challenger.

The Challenger disaster has several issues which are relevant to engineers. These issues raise many questions which may not have any definite answers, but can serve to heighten the awareness of engineers when faced with a similar situation. One of the most important issues deals with engineers who are placed in management positions. It is important that these managers not ignore their own engineering experience, or the expertise of their subordinate engineers.

Often a manager, even if she has engineering experience, is not as up to date on current engineering practices as are the actual practicing engineers. She should keep this in mind when making any sort of decision that involves an understanding of technical matters.

Another issue is the fact that managers encouraged launching due to the fact that there was insufficient low temperature data. Since there was not enough data available to make an informed decision, this was not, in their opinion, grounds for stopping a launch.

This was a reversal in the thinking that went on in the early years of the space program, which discouraged launching until all the facts were known about a particular problem. This same reasoning can be traced back to an earlier phase in the shuttle program, when upper-level NASA management was alerted to problems in the booster design, yet did not halt the program until the problem was solved. To better understand the responsibility of the engineer, some key elements of the professional responsibilities of an engineer should be examined.

This will be done from two perspectives: the implicit social contract between engineers and society, and the guidance of the codes of ethics of professional societies.

As engineers test designs for ever-increasing speeds, loads, capacities and the like, they must always be aware of their obligation to society to protect the public welfare. After all, the public has provided engineers, through the tax base, with the means for obtaining an education and, through legislation, the means to license and regulate themselves.

In return, engineers have a responsibility to protect the safety and well-being of the public in all of their professional efforts. This is part of the implicit social contract all engineers have agreed to when they accepted admission to an engineering college.

An investigation board determined that a large piece of foam fell from the shuttle's external tank and breached the spacecraft wing. This problem with foam had been known for years, and NASA came under intense scrutiny in Congress and in the media for allowing the situation to continue. The Columbia mission was the second space shuttle disaster after Challenger , which saw a catastrophic failure during launch in The Columbia disaster directly led to the retirement of the space shuttle fleet in Columbia was the first space shuttle to fly in space; its first flight took place in April , and it successfully completed 27 missions before the disaster.

On its 28th flight, Columbia left Earth for the last time on Jan. At the time, the shuttle program was focused on building the International Space Station. However, Columbia's final mission, known as STS, emphasized pure research. The seven-member crew — Rick Husband, commander; Michael Anderson, payload commander; David Brown, mission specialist; Kalpana Chawla , mission specialist; Laurel Clark, mission specialist; William McCool, pilot; and Ilan Ramon, payload specialist from the Israeli Space Agency — had spent 24 hours a day doing science experiments in two shifts.

They performed around 80 experiments in life sciences, material sciences, fluid physics and other matters before beginning their return to Earth's surface. During the crew's 16 days in space, NASA investigated a foam strike that took place during launch. About 82 seconds after Columbia left the ground, a piece of foam fell from a "bipod ramp" that was part of a structure that attached the external tank to the shuttle.

Video from the launch appeared to show the foam striking Columbia's left wing. It was later found that a hole on the left wing allowed atmospheric gases to bleed into the shuttle as it went through its fiery re-entry, leading to the loss of the sensors and eventually, Columbia itself and the astronauts inside. Several people within NASA pushed to get pictures of the breached wing in orbit. The Department of Defense was reportedly prepared to use its orbital spy cameras to get a closer look.

The landing proceeded without further inspection. On Feb. Just before 9 a. EST, however, abnormal readings showed up at Mission Control. Temperature readings from sensors located on the left wing were lost. Then, tire pressure readings from the left side of the shuttle also vanished. The Capcom, or spacecraft communicator, called up to Columbia to discuss the tire pressure readings. At a. At that point, Columbia was near Dallas, traveling 18 times the speed of sound and still , feet 61, meters above the ground.

Mission Control made several attempts to get in touch with the astronauts, with no success.