Ice Space Shuttle Challenger disaster

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ice on launch tower hours before challenger launch


the thiokol engineers had argued low overnight temperatures (−8 °c (18 °f) evening prior launch) result in srb temperatures below redline of 4 °c (39 °f). ice had accumulated on launch pad, raising concerns ice damage shuttle upon lift-off. kennedy ice team inadvertently pointed infrared camera @ aft field joint of right srb , found temperature −13 °c (9 °f). believed result of supercooled air blowing on joint liquid oxygen tank vent. lower air temperature , far below design specifications o-rings. low reading later determined erroneous, error caused not following temperature probe manufacturer s instructions. tests , adjusted calculations later confirmed temperature of joint not substantially different ambient temperature.


the temperature on day of launch far lower had been case previous launches: below freezing @ −2.2 −1.7 °c (28.0 28.9 °f); previously, coldest launch had been @ 12 °c (54 °f). although ice team had worked through night removing ice, engineers @ rockwell still expressed concern. rockwell engineers watching pad headquarters in downey, california, horrified when saw amount of ice. feared during launch, ice might shaken loose , strike shuttle s thermal protection tiles, possibly due aspiration induced jet of exhaust gas srbs. rocco petrone, head of rockwell s space transportation division, , colleagues viewed situation launch constraint, , told rockwell s managers @ cape rockwell not support launch. rockwell s managers @ cape voiced concerns in manner led houston-based mission manager arnold aldrich go ahead launch. aldrich decided postpone shuttle launch hour give ice team time perform inspection. after last inspection, during ice appeared melting, challenger cleared launch @ 11:38 am est.









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