Shuttle Challenger: Does over confidence impede decision making?


In 1986, a watching world was rocked as the Space Shuttle Challenger suffered a catastrophic event just over a minute into its flight. All members of the shuttle’s crew, including a school teacher, died.

Allan McDonald, an engineer from Morton Thiokol, watched on with his colleagues from the NASA control room as the shuttle exploded.

And yet, shocked as he was, he was not completely surprised. Only the evening before, McDonald had refused to sign off the launch recommendation because of safety concerns.

How safe is safe?

McDonald, who had already had a successful career in engineering and aeronautics before becoming director of the Space Shuttle Solid Rocket Motor Project, had concerns about the temperature which could be withstood by the rocket’s O-rings.

An O-ring is a piece of rubber which seals a joint. In this case, each joint on the rocket’s sections was sealed with two rubber O-rings. While insignificant in size, each piece of rubber was expected prevent leaks of hot, high-pressure gases produced by the burning solid propellant inside. It had been McDonald’s team who had worked on these small but vital parts.

The launch of the shuttle had already been postponed several times. A weather front. A problem with a bolt. More weather. It wasn’t looking good for the launch.

And then the winds calmed for a while and January 28 seemed like a good day to go. But there was a problem, the temperature was forecast to be as low as -1 degrees centigrade. And that would have been fine – if the engineers could have been sure that it wouldn’t have an adverse effect on the O-rings.

The turning point where no-one turned

The night before the launch, McDonald’s team expressed concerns about the ability of the O-rings to withstand the temperatures that were forecast.

And so, like all diligent employees, him and his team called a meeting with NASA.

On the phone call that followed, one NASA engineer expressed his distaste at the late hour that McDonald was raising this concern. In the end, the space agency decided that there was not enough evidence that the rubber would be adversely affected by the temperature.

So they gave a launch order – and history was made for all the wrong reasons.

Houston, we have a [confidence] problem

The shuttle disaster became the subject of a huge investigation and much media attention during which time McDonald played a huge role in telling of how a group of loud voices ignored a problem with a tiny piece of rubber.

Freakonomics spoke with McDonald in 2014 and he said something that really resonates here:

What really happened was typical I think in large bureaucratic organizations, and any big organization where you’re frankly trying to be a hero in doing your job. And NASA had two strikes against it from the start, which one of those is they were too successful. They had gotten [sic.] by for a quarter of a century now and had never lost a single person going into space, which was considered a very hazardous thing to do. And they had rescued the Apollo 13 halfway to the moon when part of the vehicle blew up. Seemed like it was an impossible task, but they did it. […] it gives you a little bit of arrogance you shouldn’t have. And a huge amount of money [was] involved. But they hadn’t stumbled yet and they just pressed on. So you really had to quote “prove that it would fail” and nobody could do that.

That quote sums up pretty neatly a problem that occurs in groups. It’s frequently the voices that are offering a dissenting opinion who are overruled for one reason or another.

In this case, NASA appears to have been so confident that they could handle anything that they ignored the possibility that a group of experts in their employ might be suggesting that they could not.

After all, they’d rescued a space ship that blew up in space once before.

But take a look at what Roger Boisjoly, the engineer who had first blown the whistle on the O-rings, later wrote in a paper on the ethics of this fiasco:

“The caucus constituted the unethical decision-making forum resulting from intense customer intimidation. NASA placed [Morton Thiokol] in the position of proving that it was not safe to fly instead of proving that it was safe to fly. Also, note that NASA immediately accepted the new decision to launch because it was consistent with their desires and please note that no probing questions were asked.”

Sound familiar?

We’ve all been in decisions where a dissenting voice was trounced because he or she was an outlier. Their opinion seemed to be so contradictory to the group that they were discounted in favour of the majority rule.

Only, you get the feeling that the culture that produced the horrific decision to launch was one where many people didn’t want to say that success was unlikely.

Hopefully, by now, we can all agree that allowing people to have the most free expression will produce better results by surfacing information which questions conventional wisdom.

Our emphasis on anonymity and quantifiable data in polls is for this exact purpose:

If you know something that could be mission critical, you should feel safe to say so.