Challenger (STS-51L)

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NASA has believed that they have harnessed the power of mother nature and because they can get to the moon, they must be able to do nearly everything else as well. On January 28, 1986 mother nature won. In this report you will learn the main cause of the shuttles destruction, other problems regarding the launch, and the bureaucracy which killed seven people. Information about how America reacted to the disaster is also included.

Problems on the Pad

The shuttle transport system (STS) holds thousands of gallons of liquid oxygen in the external tank (ET) to fuel the three main engines (Extreme Machines). At a temperature well below 100 degrees Celsius and with the outside temperature dropping to 22 degrees Fahrenheit the night before, icicles more than a foot long were reported (Jensen, 297. CBS News)
Rockwell International was responsible for the orbiterÕs (the white plane-like part) into the STS and the space shuttleÕs main engines (SSMEs) of which there are three (Kennedy, 7.39)
RockwellÕs Dr. Rocco Petrone and NASAÕs Charles Stevenson both agreed that the ice crystals could damage the thermal tiles on the orbiter and were also concerned about aspiration on the morning of January 27, 1986. Aspiration occurs when the solid rocket boosters (SRBs) are ignited. The SRBs take in a huge amount of air at high speed to begin combustion, high enough to pull in ice crystals and damage the booster internally (Jensen, 315).
Stevenson was quoted as reporting ÒIÕd say the only choice you got today is not to go. WeÕre just taking a chance of [having an ice crystal] hitting the vehicle,Ó to his superiors which included the Launch Director, Gene Thomas (Jensen, 315).

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The Solid Rocket Boosters

Although ice crystals didnÕt seem to bother NASA, the solid rocket boosters should have. To hurl the shuttle out beyond the EarthÕs atmosphere and gravitational pull, enormous power must be used. Each SRB produces 2,650,000 pounds of thrust (at launch) for a combined total of 5,300,000 pounds of raw power. To achieve this the SRBs use a solid fuel (Kennedy, 7.29). ThereÕs a risk that goes along with using solid propellant, however. Once these engines are started, they canÕt be shut off (Extreme Machines).
These massive engines were designed and built by the Thiokol Corporation in Utah (Kennedy, 7.40). For the STS-51L mission, Thiokol reported the readiness of the SRBs to the Marshal Space Flight Center (MSFC) in Huntsville, Alabama. MSFC and the other NASA field facilities (Johnson Space Center, Kennedy Space Center, etc.) were known for their rivalry. If someone at a site were to declare that the shuttle wasnÕt fit for launch the other centers would say, ÒWhy hasnÕt it been fixed? YouÕre not doing your job.Ó William Lucas MSFC Administrator, and his team werenÕt going to let anything create a problem - not even a direct objection to the launch by Thiokol (Jensen, 295-297).
Engineers in Utah had serious concerns about the temperature forecasted for the night before the launch on January 28, 1986. In the STS-51C flight the O-Rings which sealed the four sections of each SRB together had shown extreme wear due to the cold. 51-C had also experienced minor Òblow-by.Ó Hot gasses punched right through the primary O-Ring and were leaking out of the side of the SRB. The secondary O-Ring was not able to react in the usual 170 milliseconds because the cold had made it too stiff (Jensen 297-299).
Bob Lunt, citing the information just presented to the MSFC Team told NASA to postpone the launch until the temperature was at least 53 degrees Fahrenheit. MarshallÕs Deputy Director for Science and Engineering, George Hardy, refused to even recognize this as a serious problem. A contractor at
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level four of launch approval was not going to demand a veto and get it. Hardy, who was at level three, declared the issue not to be a problem and didnÕt pass the information on to level two. Hardy gave level two a go for launch (Jensen, 300).

The Crew

Dick Scobee, a 47 year-old Vietnam veteran led the team as shuttle commander. Scobee had already successfully completed 41-C. Scobee nor any of the crew were informed of any SRB problem (Jensen, 302). A new shuttle pilot, Michael Smith, was also a Vietnam veteran. This would have been SmithÕs first time in space