THE CHALLENGEREXPLOSION

Faiz Almansour

Alemu Azanaw

Rachel Downen

Timothy Herbig

Angie Schneider

Introduction

• The Challenger Space Shuttle exploded on January 28, 1986

• Caused by an O-ring failure• All 7 crew members perished

Process Description

O-ring• SRB segments

diameter growth• Clearance between O-

ring and upstream channel wall

• Putty• Temperature effects

Timeline

Night of Jan. 27th

• Teleconference with Marshall, Kennedy, and Thiokol

• Launch recommendation signed• Ice teams work through the night removing ice

Jan. 28th

• 1:00 AM• Tanks started to be filled with fuel

• 10:30 AM• Flight delayed for extra ice inspection

Timeline (continued)

• 11:38 AM (T = 0)• The Challenger launches

• T + 0.836 s• Eight puffs of smoke

• T + 58.788• Flame appears on right SRM

• T + 59.262• Continuous plume on right SRM

• T + 65.164• Rocket starts to deviate from course due to plume

Timeline (continued)

• T + 72.564• Hydrogen tank pressure decreases

• T + 73.143• All engines respond to loss of fuel and liquid

oxygen

• T + 73.327• Intense white flash

• T + 110.250• SRBs destruct

http://www.youtube.com/watch?v=j4JOjcDFtBE

Root Causes

• O-rings failed• Technical failure• Previous warnings• Untested conditions

• Pressure to launch• Miscommunication

Ultimate Results

• Death of all seven crew members• Space Shuttle program suspended for

32 months• Thiokol accepted liability and forfeited

$10 million of their incentive fee• Country watching the launch live

demoralized• Replacement Shuttle for the Challenger

cost $1.7 billion

Lessons Learned

• Communication is key• Only operate in tested conditions• Safety over schedule

Summary

• O-ring failure resulted in Challenger explosion on Jan. 28, 1986

• Pressure to launch led to operation in unsafe conditions

• Replacement Shuttle for the Challenger cost $1.7 billion

• 7 people lost their lives• 3 main lessons were learned from this

disaster

References• McDonald, Allan J., and James R. Hansen. Truth, Lies, and O-rings:

Inside the Space Shuttle Challenger Disaster. Gainesville: University of Florida. 2009.

• “NASA – National Aeronautics and Space Administration.” NASA. Web. 01 Mar. 2012. <http://www.nasa.gov/centers/kennedy/about/information/shuttle_faq.html>.

• “Report of the Presidential Commission on the Space Shuttle Challenger Accident.” Presidential Commission Report on Space Shuttle Challenger Accident. Web. 28 Feb. 2012. <http://science.ksc.nasa.gov/shuttle/missions/51-l/docs/rogers-commission/table-of-contents.html>. 1986.

• Vaughan, Diane. The Challenger Launch Decision: Risky Technology, Culture, and Deviance at NASA. Chicago: University of Chicago. 1996.

• “What Went Wrong.” Online Ethics Center for Engineering. 29 Aug. 2006. Web. 01 Mar. 2012. <http://www.onlineethics.org/cms/12707.aspx>.

Questions?