Back to the future: 1979-1989
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T+73 — the Challenger Space Shuttle disaster

When tragedy struck an 1980s icon.


  • Author:
  • A staff writer
    National Library of Scotland

On 28 January 1986 the space shuttle Challenger broke apart just 73 seconds into its flight off the coast of Cape Canaveral in Florida, at 11.30am Eastern Standard time.

It was a tragedy that would have reverberations across the country in the months and years to come, but while spectators in Florida stood shocked at what was unfolding before their eyes, in California — three hours behind — it would have been the start of another normal sunny school day.

As a student in California, I was used to hearing about the space shuttle launches. They were never really a distraction from friends, MTV or whatever else I was preoccupied with at the time. At school we were used to hearing the sonic boom as whichever space shuttle mission punched its way back into the atmosphere to land at Edwards Air Force base some 100 miles north of Los Angeles, usually during lunchtime. It barely gave my friends and I pause for thought sitting out in the tree-lined lunch area, we all knew it wasn't anything out of the ordinary.

My dad also worked for a company that had links to the space shuttle programme. Every once in a while he would bring home a new badge marking a different space shuttle mission which he would keep in a drawer. His company was one of the more than 400 private subcontractors across the USA and Canada that provided components for the space shuttle — evidence of the extensive economic supply chain of the shuttle programme and in particular the dominance of the aerospace industry in Southern California.

Expansion of American space exploration

Since the early 20th century, California had been a significant force in the aerospace industry and in the heyday of the 1960s space program, North American Aviation's Downey facility in Southern California employed up to 25,000 workers to build the Apollo command module.

It's hard to overstate the extent to which post-war Southern California was built on defence spending. In his definitive account of the period, 'Golden Dreams: California in an Age of Abundance, 1950-1963,' Kevin Starr wrote: 'The Department of Defense awarded one-quarter of all its contracts to California in the 1950s. Between 1952 and 1962, the Department of Defense funnelled more than $50 billion into California, twice the amount received by any other state.'

And in the 1980s as President Reagan launched a new military race with the Soviet Union, employment surged again. This turbo-charged space race had implications for NASA' s budget and missions as well and for the industry in California, it ushered in a new technological gold rush that could be summed up as 'bigger, better, faster, more'.

With a resurgent American drive towards space dominance, in 1984 Ronald Reagan also launched the 'Teacher in Space' programme designed to elevate the teaching profession to an honoured place in the national consciousness and to inspire students' interest in math, science and space exploration. After a rigorous selection process, select teachers would take part in space shuttle missions and on their return, share their experiences with students thereby inspiring a new generation of Americans in the great endeavour of space exploration.

The first teacher selected from this programme for the upcoming Challenger mission was Christa McAuliffe from New Hampshire and NASA had arranged for many schools across the country, mainly on the East Coast, to view the Challenger launch live on NASA TV. According to a New York Times poll, 48 per cent of 9-13 year-olds watched the launch at school. In California, the time difference meant this wasn't possible, but by the middle of the day we were all made aware of the disaster as the tidal wave of information made its way across the country and the world. One study reported that 85 per cent of Americans had heard the news within an hour of the event.

Impact of a national tragedy

It's hard to quantify the impact of the disaster on the American psyche where the prospect of failure is anathema to its image of itself. To see it live, televised to the entire world as it happened is of another category altogether. In the USA, we are schooled to have a proud reverence for national achievements and there are few more iconic moments than seeing seven astronauts being suited-up before going into space, hearing the NASA countdown and seeing the shuttle lifting off from Cape Canaveral trailing orange soda flames and white plumes. Before that point, for me and my school friends it was almost so commonplace to see or hear of yet another launch that the upcoming Challenger launch hardly even registered.

What I didn't know at the time was that the disaster would lead to at least one study which looked at how traumatic events affected young people's mental health. One study found that memories of the Challenger disaster were similar to memories of experiencing single, unrepeated traumas. It also showed that young people remembered vividly who they were with and what they were doing at the time when they heard the news. Unsurprisingly, young people on the East Coast who were more likely to have seen it live on television in classrooms were able to recall it more easily and were more emotionally affected by it than those on the West Coast like myself. While I'm unable to recall my own reaction to the disaster on that January day, one memory that stands out is being at school not long afterward and hearing about a visitor coming in to talk to students about the event and hear their reactions.

several crew members actually survived the initial break-up of the shuttle

Of course we already had a school psychologist (as did most other schools at the time) and this being California, it wasn't unusual to hear of efforts being made to get students to open up about their thoughts and feelings on any number of issues. What made this visit stand out for me was that for the first time, a national disaster seemed to have such immense reverberations that it was deemed of interest to gauge my and my fellow students' reactions. I can't recall an event before or since where this has happened and is evidence, I think, of just how deep the wound to the American psyche this disaster was at the time.

The break-up of the Challenger space shuttle took place off the coast of Cape Canaveral, Florida over the Atlantic Ocean at 11:39 Eastern standard time. It killed all seven crew members, five astronauts and two payload specialists, one of whom was Christa McAuliffe, the first teacher in space. While millions saw the footage and what looked like the total destruction of the shuttle, several crew members actually survived the initial break-up of the shuttle, but the crew compartment had no escape mechanism and the impact with the sea at terminal velocity was unsurvivable.

What caused the break up was the failure of the O-ring seals. A very small component, but one whose failure was disastrous that January day. The O-ring seals were circular gaskets that sealed the solid rocket boosters (SRBs). The seals' function was to contain the hot pressure gases produced by the burning of the solid propellant inside the two rocket boosters and force them out of a nozzle at the bottom-end of each rocket. The seals on the right SRB had failed due to the low temperature of minus 0.5°C at the time of launch. They had never been designed to handle the unusual cold conditions of the launch day and several engineers reported the risk of this happening but these were dismissed by NASA management.

Predictions of technical problems

As early as 1971 during the space shuttle design process, a report produced by aerospace company McDonnell Douglas flagged up the safety record of the solid rockets. The report stated that 'if burnthrough occurs adjacent to [liquid hydrogen/oxygen] tank or orbiter, timely sensing may not be feasible and abort not possible'. This chillingly but accurately predicted the Challenger disaster.

The company responsible for the construction and maintenance of the O-ring joints in the SRBs was Morton Thiokol, a company based in Utah with laboratories and manufacturing facilities across the United States. In its own original design, the O-rings were supposed to close tightly due to ignition forces. In a test carried out in 1977 with pressurized water to simulate the effect of the rocket booster combustion, the metal parts bent away from each other, opening a gap through which gases could leak.

Engineers at the Marshall Space Flight Center in Huntsville, Alabama — the USA government's civilian rocketry and spacecraft propulsion research centre — wrote to George Hardy, the manager of the Solid Rocket Booster project at NASA several times to say the design was unacceptable, but Hardy never forwarded these memos to Morton Thiokol and the field joints were accepted for flight in 1980.

By 1985 the rocket boosters of seven of the nine shuttle launches had evidence of some O-ring erosion and both the Marshall Space Center and Morton Thiokol realised that they had a problem. A redesign of the joint was started but they didn't call for shuttle missions to be stopped while this was happening. Instead they treated it as an acceptable risk. Later, a member of the Rogers Commission — the commission appointed by President Ronald Reagan to investigate the accident — compared the situation to an airline allowing one of its planes to continue flying despite evidence that one of its wings was about to fall off. In the same year Bob Ebeling, one of the engineers at Morton Thiokol, wrote a memo flagging up concerns over low temperatures and O-rings entitled 'Help!' so that it would be read. The forecast for the morning of 28 January 1986 predicted unusually low temperatures close to 30°F (minus 1°C), the absolute minimum allowed for launch though the shuttle was never given the all-clear technically to operate in temperatures that low.

With this sub-optimal forecast, the NASA team recalled the Morton Thiokol warning and contacted the company. When one of the Thiokol managers asked about a launch at a temperature at 18°F (minus 7°C) Ebeling answered '[W]e're only qualified to 40°[F] … what business does anyone even have thinking about 18°, we're in no-man's land' (quoted in 'Remembering the mistakes of Challenger'). The Thiokol team agreed that a launch at these temperatures was a potentially fatal risk and immediately recommended to NASA that they postpone the launch to later in the day when temperatures would be higher. On the evening of 27 January, a conference call with NASA took place where the company was expected to provide robust justification for recommending a postponement.

That night [Bob] Ebeling told his wife that the Challenger shuttle would blow up.

Several Thiokol engineers, including author of the warning memo Bob Ebeling, reiterated serious concerns about the effects of low temperatures on the O-rings that sealed the joints of the SRBs. They argued that they didn't have enough data to show the rings would operate properly under sub-optimal conditions. The rings themselves were designated as a 'Criticality 1' component which meant there was no back up if primary and secondary rings failed. Such a failure would be catastrophic.

Thiokiol management did initially agree with the company's engineers but NASA management did not support delaying the launch. During the call one of the NASA team is reported to have said 'My God, Thiokol, when do you want me to launch — next April?' (quoted in 'Remembering Roger Boisjoly: He Tried To Stop Shuttle Challenger Launch'). NASA simply didn't believe what Thiokol engineers were telling them. One of their arguments was that if the primary O-ring failed to seal properly, the secondary one would still seal. As mentioned above, there was no data to back this up and in any case relying on a back-up for a 'Criticality 1' component like this was prohibited.

According to Ebeling a second conference call was scheduled but only between NASA and Thiokol management. Thiokol management ignored its own engineers' warnings and now recommended that the launch go ahead as scheduled. NASA didn't probe further. That night Ebeling told his wife that the Challenger shuttle would blow up.

Countdown to catastrophe

At T+37 and for another 27 seconds after, the Challenger shuttle experienced a series of wind shear events, microscale meteorological phenomena that cause a variation of wind, that were stronger than on any previous flight.
At T+58 a tracking camera captured the beginning of a plume forming near the bottom end of the right SRB and hot gas was starting to leak through the growing hole in one of the right-hand SRB joints. This wasn't picked up by the Challenger crew or by ground control in Houston. Yet another factor that contributed to the disaster.
At T+64 the plume changed shape, indicating that a leak had started in the liquid hydrogen (LH2) tank. At this stage everything seemed normal to the crew and ground control. At T+68 one of the flight controllers informed the crew that they were 'go at throttle up'. Shuttle Commander Dick Scobee replied with the confirmation 'Roger, go at throttle up'. This was the last communication from Challenger.

At T+72 the last statement actually captured by the crew cabin recorder came just half a second afterward when Pilot Michael J Smith said 'Uh-oh'. By this point he might have been reacting to alerts lighting up his control panel.

The break-up of the shuttle started at T+73.162 seconds at an altitude of 48,000 feet. The crew cabin made of reinforced aluminium was one of the more robust sections and actually survived the vehicle break-up. It continued along a ballistic trajectory with an altitude peaking at 65,000 feet.

The fate of the crew

At least some of the crew were probably alive and conscious for a short time after the break-up. Three of the four Personal Egress Air Packs (PEAPs) that were recovered were found to have been activated. Investigators also found while analysing the wreckage that several electrical system switches on Pilot Mike Smith's panel were moved from their initial positions and later tests showed that neither the force of the explosion or impact with the sea could have moved them.

It's not known how long any crew member remained conscious for and it largely depended on whether the cabin maintained pressure. If it didn't, they would have lost consciousness within a few seconds although some experts believe that most if not all of the crew were alive and possibly conscious during the entire descent of the cabin until the impact with the sea.

The cabin hit the ocean surface at roughly 207 miles per hour which would have torn the crew from their seats and killed them instantly. For all those watching that January morning, any survival beyond the initial explosion would have been unfathomable.

Lessons learned in the aftermath

On 9 June 1986, the Rogers Commission set up by President Reagan in the aftermath of the disaster published its findings. The report found that the accident was caused by a failure in the O-rings sealing a joint on the right solid rocket booster. The report also referred to contributing factors of the disaster such as the failure by Thiokol and NASA managers to respond appropriately to the dangers flagged up by the engineers. It also criticised the decision-making process stating: '… failures in communication … resulted in a decision to launch 51-L based on incomplete and sometimes misleading information, a conflict between engineering data and management judgements, and a NASA management structure that permitted internal flight safety problems to bypass key Shuttle managers.'

While the report identifies at length and in detail the technical reasons that caused the shuttle components to fail, at the heart of the tragedy are seven individuals who lost their lives in the pursuit of science and discovery, including a teacher whose primary aim on that mission was to inspire young people. In the end it took nine days to locate the wreckage and a painstaking effort to remove the remains of the crew. And while the nation mourned the loss of a group of selfless and dedicated professionals, what was striking was the ramifications it had for corporate responsibility and accountability. The damning report on the dismissive attitude to risk by NASA and Thiokol management would have serious implications for any future space mission. Corporate whistleblowing would now enter the public lexicon. It was time to take stock.

For a young girl in California, caught up in her own juvenile pre-occupations, the impact the disaster would take 33 years to start to unpick. What strikes me most now isn't the disaster itself nor the human and technical failings but the bravery and selflessness of the seven astronauts that put their lives at risk in the pursuit of advancing science and exploration. It seems to me that all human endeavour, all pursuit of the unknown is laden with risk yet time and again we as a species meet the risk head on and so I'm reminded of the lines in Alfred Lord Tennyson's great poem 'Ulysses':

'That which we are, we are;
One equal temper of heroic hearts
Made weak by time and fate, but strong in will
To strive, to seek, to find, and not to yield.'

Further reading

  • 'The Challenger 1986: A space shuttle explodes after lift-off' by Liz Gogerly (Oxford: Raintree, 1986) [National Library of Scotland shelfmark: HB2.208.1.503].
  • 'Golden dreams: California in an age of abundance, 1950-1063' by Kevin Starr (Oxford University Press, 2011) [Shelfmark: PB8.212.526/1].
  • 'Historical dictionary of the Reagan-Bush era' by Richard Steven Conley (Plymouth: Scarecrow Press, 2007) [Shelfmark: HB2.207.10.983].
  • 'NASA space shuttle: 1981 onwards (and models): An insight into the design, construction and operation of the NASA space shuttle' by Donald Baker (Sparkford: Haynes, 2011) [Shelfmark: HB5.211.4.70].
  • 'The space shuttle disaster' by James McCarter (Hove: Wayland, 1988) [Shelfmark: W3.88.121].
  • 'Space shuttle launch system 1972-2004' by Mark Lardas and Ian Palmer (Oxford: Osprey, 2004) [Shelfmark: PB4.206.23/2].


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