morton-thiokol manufactures the solid rocket boosters for NASA the rocket boosters are strapped to each side of the shuttles main liquid fuel tank and provide the explosive force to lift the spacecraft off the ground these huge Rockets are made up of four motor segments fitted with solid fuel designed to be reused after each launch the joints between each segment have to withstand the vast forces produced during blast-off each segment is sealed against the next segment with two rubber seals called a rings for the rocket boosters to work the joins have to function perfectly when the rocket booster sections are slotted together the joint is sealed by two o-rings [Music] the o-rings are designed to form a seal against the superheated rocket exhaust gases that are produced at incredible pressure during launch the first o-ring should do the job the second o-ring is a safety backup bozhe lays photos of flight 51 sees joints reveal hard evidence there is a major design flaw he discovers that hot gas has blasted past the first ring and burned the second backup o-ring throughout 1985 NASA has a very ambitious launch scheduled flight 51c is the first of nine planned launches and the pressure is on to keep the shuttle flying any delays would ultimately cost money and jobs were at stake they didn't want to hear because I believe they wanted to ensure for the company they would get the follow-on contract that was in negotiations with NASA at that point in time that contract was worth over a billion dollars by the time the teleconference starts launches just 13 hours away the success of this mission and the lives of the seven astronauts hang on one simple question how will the o-rings react to the cold temperatures predicted for launch the next morning at low temperatures the o-rings are not so elastic they won't seal properly it'll be like putting a brick into a crack versus a sponge the grease too will be affected it will be thicker and not as slick we will have a higher oring actuation time and if that happens we will approach the threshold of secondary sealed pressurization capability so we have a situation where neither the primary seal nor the secondary seal will function the engineers at Morton Thiokol are confident NASA will stop the Challenger launch they now wait for the official response for God's sake Morton Thiokol when do you want me to launch next April you guys are generating new launch criteria here we have been flying for four years with a known condition in these joints considered and accepted by Thiokol accepted by me and all levels of NASA management think about this think about your data with their next multi-million dollar contract still under negotiation with NASA the Morton Thiokol managers are under intense pressure at this point senior vice president Gerald Mason intervenes Joe asking can take a five minute caucus offline [Music] weary could we take five minutes we have to make a management decision let's look over the data again and consider Larry Malloy's points if we launch at the predicted temperatures we are out of our experience base even if we take 40 degrees as the temperature floor we are still way out of our database in launching at these low temperatures we are moving away from goodness we're covering the same ground again we're just spinning our wheels let's take a vote do we recommend a launch Joe I think it's alright the vice president of engineering is on the fence and now he's being pressured to change his mind but Marshall here our position is that although temperature effects are a concern the data predicting blow-by are inconclusive now are there any disagreements or any other comments concerning the Thiokol recommendation [Music] the pressure is intense no one raises any objections not even Beaujolais at NASA the silence means go for launch pilot Mike Smith followed by Christa McAuliffe feature in space Lucca and the temperature hits 36 degrees 30 degrees colder than any previous shuttle launch [Music] space shuttle mission and it is challenger now heading downrange Roger roll Challenger I am confirmed challenger now heading down a range engines beginning throttling down now at 94% the explosion blasts the shuttle free it is tumbling through the atmosphere at 1,250 miles per hour the no section is torn off it contains the crew cabin and the seven astronauts [Music]