The Challenger DisasterThe Challenger Disaster

ByByDiana ClarkeDiana Clarke

The OrbiterThe Orbiter

Dimensions: 122’ L x 78’ W x 57’ HDimensions: 122’ L x 78’ W x 57’ H Crew size: Up to 8 peopleCrew size: Up to 8 people Weight: 160,000 lbs (unfueled)Weight: 160,000 lbs (unfueled) 3 SSME’s 3 SSME’s

- - Single engine produces 375,000 lbs of thrustSingle engine produces 375,000 lbs of thrust- - 104% thrust104% thrust (sea level / vacuum): 393,800 lbf / 488,800 lbf (sea level / vacuum): 393,800 lbf / 488,800 lbf

The External Liquid Fuel Tank The External Liquid Fuel Tank (EFT)(EFT)

Fuels the 3 SSME’sFuels the 3 SSME’s Carries liquid hydrogen and liquid oxygenCarries liquid hydrogen and liquid oxygen Attached to the bottom of the orbiterAttached to the bottom of the orbiter CapacityCapacity

- top portion: 143,000 gallons of liquid oxygen- top portion: 143,000 gallons of liquid oxygen- bottom portion: 385,000 gallons of liquid hydrogen - bottom portion: 385,000 gallons of liquid hydrogen

The Solid Rocket Boosters The Solid Rocket Boosters (SRB)(SRB)

Attached to the EFTAttached to the EFT Most powerful boosters ever builtMost powerful boosters ever built Provide 80% (approx 3.3 million lbs) of thrust at launch Provide 80% (approx 3.3 million lbs) of thrust at launch Burn time: 2 minutesBurn time: 2 minutes Jettisoned after fuel exhaustJettisoned after fuel exhaust

Challenger AccomplishmentsChallenger Accomplishments

11stst seven and eight member crews in orbit seven and eight member crews in orbit11stst EVA (cargo bay) EVA (cargo bay)11stst to carry a female astronaut to carry a female astronaut11stst night launch and landing night launch and landing11stst untethered manwalk from an orbiter untethered manwalk from an orbiter11stst capture, repair & redeploy of non capture, repair & redeploy of non

functioning satellites functioning satellites 22ndnd orbiter to fly in space orbiter to fly in space

The CrewThe Crew

Francis Scobee (Commander)Francis Scobee (Commander)Michael J. Smith (Pilot)Michael J. Smith (Pilot)

Ronald McNair (Mission Specialist)Ronald McNair (Mission Specialist)Judith A. Resnick (Mission Specialist)Judith A. Resnick (Mission Specialist)Gregory B. Jarvis (Payload Specialist)Gregory B. Jarvis (Payload Specialist)

Sharon Christa McAuliffe (Payload Specialist) Sharon Christa McAuliffe (Payload Specialist) Ellison Onizuka (Mission Specialist)Ellison Onizuka (Mission Specialist)

STS – 25 Mission Flight PlanSTS – 25 Mission Flight Plan

6 days, 34 minutes6 days, 34 minutesObjectivesObjectives

- Technology- Technology

- Science- Science

- Public education- Public education

Launch DelaysLaunch Delays Original launch date January 22, 1986Original launch date January 22, 1986 Changed to January 23Changed to January 23rdrd and 24 and 24thth

- due to previous mission- due to previous mission Reset to January 25Reset to January 25thth

- bad weather at TAL- bad weather at TAL Postponed one more day to January 26Postponed one more day to January 26 thth

- lift off time not met- lift off time not met Reset to January 27Reset to January 27thth

- hatch problems/weather concerns- hatch problems/weather concerns Rescheduled to January 28, 1986 at 9:38 amRescheduled to January 28, 1986 at 9:38 am

Pre-Launch ConcernsPre-Launch Concerns 01/28/86 01/28/86

1:30 am - Ice formation noted1:30 am - Ice formation noted 7:00 am - Icicles found hanging at launch site7:00 am - Icicles found hanging at launch site 8:30 am - Crew enters shuttle 8:30 am - Crew enters shuttle

- 2 hour delay (fire detection system failure)- 2 hour delay (fire detection system failure) 9:00 am – Mission management team meets one last time9:00 am – Mission management team meets one last time

The TragedyThe Tragedy

11:38 Lift-off (T=0)11:38 Lift-off (T=0) T+.678 Puff of smoke T+.678 Puff of smoke

T+.836 and 2.50 Puffs of smoke T+.836 and 2.50 Puffs of smoke darkendarkenT+3.375 Last Puff of smoke is T+3.375 Last Puff of smoke is seenseenT+58.788 Plume notedT+58.788 Plume notedT+59.262 Well-defined plumeT+59.262 Well-defined plumeT+60.00 Telemetry pressure T+60.00 Telemetry pressure differential noted differential noted

The TragedyThe Tragedy

T+64.660 Flame breaches EFTT+64.660 Flame breaches EFTT+72.20 Lower strut attaching SRB to EFT severedT+72.20 Lower strut attaching SRB to EFT severedT+72.525 Sudden acceleration to the rightT+72.525 Sudden acceleration to the rightT+73.00 Smith, “Uh oh…”T+73.00 Smith, “Uh oh…”T+73.124 Beginning of structural failureT+73.124 Beginning of structural failureT+73.162 Vehicle break-up beginsT+73.162 Vehicle break-up begins

The TragedyThe Tragedy

T+79.00 Smoke and flame captured by TV tracking cameraT+79.00 Smoke and flame captured by TV tracking camerahttp://spaceflightnow.com/challenger/video/launch_qt.htmlhttp://spaceflightnow.com/challenger/video/launch_qt.html

Roger’s CommissionRoger’s Commission

Presidential CommissionPresidential Commission- Sally Ride, Neil Armstrong, Chuck - Sally Ride, Neil Armstrong, Chuck

Yeager and othersYeager and others InvestigationInvestigation

- Cause of failure- Cause of failure FindingsFindings

- O-Rings - O-Rings

- Weather- Weather - Ineffective communication- Ineffective communication

RecommendationsRecommendations- Redesign O-rings- Redesign O-rings

- Escape system- Escape system - Better communication- Better communication

““All of a sudden, space isn’t friendly. All of a sudden, it’s a All of a sudden, space isn’t friendly. All of a sudden, it’s a place where people can die…Many more people are going place where people can die…Many more people are going to die. But we can’t explore space if the requirement is that to die. But we can’t explore space if the requirement is that

there be no casualties; we can’t do anything if the there be no casualties; we can’t do anything if the requirement is that there be no casualties” – requirement is that there be no casualties” – Isaac AsimovIsaac Asimov