The Challenger Disaster

1
The Challenger Disaster

• By
• Diana Clarke

2
The Orbiter

• Dimensions 122 L x 78 W x 57 H
• Crew size Up to 8 people
• Weight 160,000 lbs (unfueled)
• 3 SSMEs
• - Single engine produces 375,000 lbs of thrust
• - 104 thrust (sea level / vacuum) 393,800 lbf
  / 488,800 lbf

3
The External Liquid Fuel Tank (EFT)

• Fuels the 3 SSMEs
• Carries liquid hydrogen and liquid oxygen
• Attached to the bottom of the orbiter
• Capacity
• - top portion 143,000 gallons of liquid oxygen
• - bottom portion 385,000 gallons of liquid
  hydrogen

4
The Solid Rocket Boosters (SRB)

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

5
Challenger Accomplishments

• 1st seven and eight member crews in orbit
• 1st EVA (cargo bay)
• 1st to carry a female astronaut
• 1st night launch and landing
• 1st untethered manwalk from an orbiter
• 1st capture, repair redeploy of non functioning
  satellites
• 2nd orbiter to fly in space

6
The Crew

• Francis Scobee (Commander)
• Michael J. Smith (Pilot)
• Ronald McNair (Mission Specialist)
• Judith A. Resnick (Mission Specialist)

7
STS 25 Mission Flight Plan

• 6 days, 34 minutes
• Objectives
• - Technology
• - Science
• - Public education

8
Launch Delays

• Original launch date January 22, 1986
• Changed to January 23rd and 24th
• - due to previous mission
• Reset to January 25th
• - bad weather at TAL
• Postponed one more day to January 26th
• - lift off time not met
• Reset to January 27th
• - hatch problems/weather concerns
• Rescheduled to January 28, 1986 at 938 am

9
Pre-Launch Concerns 01/28/86

• 130 am - Ice formation noted
• 700 am - Icicles found hanging at launch site
• 830 am - Crew enters shuttle
• - 2 hour delay (fire detection system failure)
• 900 am Mission management team meets one last
  time

10
The Tragedy

• 1138 Lift-off (T0)
• T.678 Puff of smoke
• T.836 and 2.50 Puffs of smoke darken
• T3.375 Last Puff of smoke is seen
• T58.788 Plume noted
• T59.262 Well-defined plume
• T60.00 Telemetry pressure differential noted

11
The Tragedy

• T64.660 Flame breaches EFT
• T72.20 Lower strut attaching SRB to EFT severed
• T72.525 Sudden acceleration to the right
• T73.00 Smith, Uh oh
• T73.124 Beginning of structural failure
• T73.162 Vehicle break-up begins

12
The Tragedy

• T79.00 Smoke and flame captured by TV tracking
  camera
• http//spaceflightnow.com/challenger/video/launch_
  qt.html

13
Rogers Commission

• Presidential Commission
• - Sally Ride, Neil Armstrong, Chuck Yeager and
  others
• Investigation
• - Cause of failure
• Findings
• - O-Rings
• - Weather
• - Ineffective communication
• Recommendations
• - Redesign O-rings
• - Escape system
• - Better communication

14

• All of a sudden, space isnt friendly. All of a
  sudden, its a place where people can dieMany
  more people are going to die. But we cant
  explore space if the requirement is that there be
  no casualties we cant do anything if the
  requirement is that there be no casualties
  Isaac Asimov