Riding Rockets

At just ten missions per year the shuttle was driving the system to its knees. The message was the same everywhere: “I need more people. I need more equipment. I need more spare parts.” But NASA didn’t have the money to buy these things. While commercial customers offset a portion of the expense, the cash flow was nowhere close to making the shuttle the pay-as-you-go enterprise promised years earlier to Congress. Significant taxpayer money was needed to underwrite the program, and those funds were fixed in the budget. The launch rate had to be doubled with the funds available. The end result was that more was being demanded of the existing manpower and equipment to achieve a higher flight rate. Everybody had a story about how this was overwhelming the various NASA teams. I recall being with an MCC controller when his boss brought in more work for him. The controller objected, “I haven’t had a day off in six weeks. My wife and kids don’t know who I am.” The supervisor was sympathetic but had no other option. “We’re all in the same boat. I don’t have anybody else. You’ve got to do it.” I could see it in both of their faces. They were exhausted, totally burned out. And they weren’t the exception. In many areas NASA only had a first string. There was no “bench” to call on for substitutes. One of our STS-41D prelaunch hangar tests ofDiscovery had been botched for that reason. The first string had been supporting the pad checkout of the shuttle being readied for the next launch, so the contractor had scraped together a team for us from God-only-knew-where. One of the technicians had apparently been called from home because he arrived in the cockpit with the smell of alcohol on his breath. It was an outrageous violation and Hank Hartsfield confronted the man’s supervisor about it. He apologized for the intoxicated worker as well as for the entire test debacle, adding, “I don’t have enough people to cover everything.”

The story was no different for the engineers at the SRB Thiokol factory in Utah. The pressure to keep flying was hammering them even while they were struggling with a major anomaly. The O-ring problem first seen on STS-2 had not gone away. In fact, it had gotten worse. Beginning with STS-41B, launched in February 1984, and up toChallenger, only three missions did not have O-ring problems. The other fifteen flights of this period returned SRBs with eroded O-rings. Astonishingly, in nine of these fifteen flights, the engineers had recorded “blow-by,” in which heat had not only eroded the primary O-rings but, for very brief moments, had gotten past those rings. On STS-51C, the blow-by had been exceptionally significant. That mission had launched in January 1985, after the stack had waited on the pad through a bitterly cold night. Engineers suspected that cold had reduced the flexibility of the rubberized O-rings, which, in turn, had allowed a more significant primary O-ring leak, resulting in a more significant blow-by. But in all cases none of the observed erosion equaled what had been recorded on STS-2’s damaged O-ring, and that mission had been fine. In effect the STS-2 experience had become the yardstick against which all following O-ring damage was being measured. If the damage was less (and it always was), then it was okay to continue flights. In what would later be defined as “normalization of deviance” inThe Challenger Launch Decision by Diane Vaughan, the NASA and contractor team responsible for the SRBs had gotten away with flying a flawed design for so long they had lost sight of its deadly significance. The O-ring deviance had been normalized into their judgment processes.

There were a handful of individuals who resisted this normalization of deviance phenomenon. Thiokol engineer Roger Boisjoly was one. In a July 31, 1985, memo to a company vice president, Boisjoly expressed his concern about continuing shuttle flights with the SRB O-ring anomaly. He concluded the memo with this prophetic sentence: “It is my honest and very real fear that if we do not take immediate action to dedicate a team to solve the problem with the field joint [a reference to the O-ring] having the number one priority, then we stand in jeopardy of losing a flight along with all the launch pad facilities.” Boisjoly feared a catastrophic failure at booster ignition that would not only destroy the shuttle and kill her crew, but would also destroy the launchpad.

Another engineer, Arnold Thompson, wrote to a Thiokol project engineer on August 22, 1985: “The O-ring seal problem has lately become acute.”