by Brooks Riley
I had an uneasy feeling on the day of the Challenger launch in January 1986. My memory tells me that I didn’t even watch it live, although I had, growing up, watched early shots into space: Alan Shepherd, John Glenn, and later, the first manned flight to the moon. I was excited by the idea of a civilian, Christa McAuliffe, flying up there with the pros of the space program. But the weather bothered me, even if I didn’t yet know about the serious technical problems with O-rings at much milder temperatures.
It was bitterly cold in Florida on the night before the launch, with record-breaking temperatures well below freezing. Although the weather was clear, there was ice everywhere, probably the result of high humidity in the air. My worry stemmed from first-hand knowledge of the destructive power of ice.
Anyone who’s ever grown up in a drafty old house knows that when winter comes, the water should be turned off and the pipes drained in those parts of the house that are unheated. If not, sub-freezing temperatures will freeze the water, the ice expanding and ultimately bursting the thickest of metal pipes. The damage comes later, after the thaw, when water starts pouring from the hole in the pipe. I know this from experience.
Wikipedia describes it this way: The effect of expansion during freezing can be dramatic, and ice expansion is a basic cause of freeze-thaw weathering of rock in nature and damage to building foundations and roadways from frost heaving. It is also a common cause of the flooding of houses when water pipes burst due to the pressure of expanding water when it freezes.
How much condensation had seeped into the rockets’ seams and frozen there, the ice expanding and putting pressure on the joints? Does it matter that the O-rings were blamed, they too having been damaged by the cold temperatures? Might there have been other damage inside the rockets as well? We’ll never know.
The fact that the O-rings held as long as they did during take-off surprised even the engineers who had tried to stop the launch. If the mysterious puff of grey smoke before lift-off (before or after ignition?) truly heralded the failure of the O-rings, how could the Challenger have managed to go 73 long seconds before it began to break apart? Could the destruction of the Challenger have been caused by ice damage?
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