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ENCORE: Challenger Disaster | Launch Day | 3

American Scandal

Hosted by Lindsay Graham

42m
Transcript

Original podcast

Summary

Written by a model from the transcript; not yet reviewed.

On the night of January 27, 1986, Thiokol engineer Roger Boisjoly and his colleagues had only two hours to prepare data showing that the Challenger's O-rings become unreliable below 50 degrees Fahrenheit, while the forecast called for 26 degrees. Despite unanimous engineering support for canceling, NASA manager Larry Malloy declared the burden of proof was on Thiokol to prove the launch unsafe. In a closed-door vote, Thiokol executives overruled their own engineers, with vice president Joseph Kilminster lowering his head and voting to proceed.

On launch morning, ice team leader Charlie Stevenson found 18-inch icicles on the launch tower and measured booster temperatures of 25 and 8 degrees. The seven astronauts, including teacher Christa McAuliffe, boarded the shuttle. About a minute after liftoff, the Challenger exploded. In the aftermath, NASA's Jesse Moore told reporters the cold weather did not play a role, while Boisjoly secretly locked his O-ring data and warning memos in his desk drawer, anticipating they would be needed for the investigation.

  • Thiokol engineers determined O-rings become unreliable at temperatures below 50 degrees Fahrenheit, making the 26-degree forecast a critical safety threshold. 1:46
  • NASA manager Larry Malloy reversed the standard safety protocol, arguing Thiokol must prove the launch is unsafe rather than NASA proving it is safe. 11:40
  • Thiokol executives overruled their own engineers' unanimous recommendation to cancel, with Kilminster voting to launch under pressure from his boss. 15:41
  • Charlie Stevenson measured booster temperatures of 25 and 8 degrees on the icy launch pad, confirming conditions far below safe thresholds. 17:48
  • Boisjoly secretly kept his O-ring data and warning memos in a locked drawer, anticipating they would be needed for the investigation. 40:06

Highlights

  • 11:13

    Malloy Reverses Burden of Proofdebate

    Malloy declares that Thiokol must prove the launch is unsafe, not NASA proving it is safe, effectively changing safety policy hours before launch.

  • 14:11

    Boisjoly Slams Photo on Tablestory

    Hearing executive Jerry Mason argue the secondary O-rings always worked as backup, Boisjoly storms across the room and slams a photo showing both primary and secondary O-rings singed with black soot.

  • 15:41

    Kilminster Votes to Launchstory

    Kilminster, knowing the engineers are right, lowers his head unable to look them in the eyes and votes to proceed, fearing Mason could hold him responsible for losing NASA's contract.

  • 17:48

    Eighteen-Inch Icicles on Launch Towerdata

    Charlie Stevenson finds 18-inch icicles covering the launch tower and must hold the railing to avoid slipping. He later measures booster temperatures of 25 and 8 degrees.

  • 30:12

    Challenger Explodes One Minute After Liftoffstory

    About a minute after launch, a flash of bright light envelops the shuttle and two white contrails emerge flying in different directions. Boisjoly walks out of the conference room wiping tears.

  • 35:02

    Abbey Tells Families No Hopestory

    NASA's George Abbey tells the astronauts' families there is no hope for the crew, then asks them to break the news to their own children.

  • 40:06

    Boisjoly Locks Evidence in Drawerstrategy

    Boisjoly hands over only his presentation slides to management and locks the rest of his O-ring data and warning memos in his desk drawer, knowing powerful people would rather they never see the light of day.

About this episode

In the tense hours leading up to the Challenger launch, engineers and managers at NASA and its contractor Morton Thiokol heatedly argue over whether to move forward, despite freezing temperatures that threaten to compromise the rocket boosters’ O-Rings. See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Transcript

0:00
42:55

7,139 words · 8 speakers

Speaker names marked are inferred from speaking time and the show’s known hosts — they are not voice-verified.

Topics

  • Challenger Disaster
  • O-Ring Failure
  • NASA Safety
  • Engineering Ethics
  • Space Shuttle
  • Whistleblowing
  • Catastrophic Failure

Page updated · transcript and summary are machine-generated