Cecil Houston, the manager of the KSC office of the Marshall Space Flight Center in Alabama, set up a three-way conference call with Morton Thiokol in Utah and the KSC in Florida on the evening of January 27 to discuss the safety of the launch.

Morton Thiokol engineers expressed their concerns about the effect of low temperatures on the resilience of the rubber O-rings. As the colder temperatures lowered the elasticity of the rubber O-rings, the engineers feared that the O-rings would not be extruded to form a seal at the time of launch. The engineers argued that they did not have enough data to determine whether the O-rings would seal at temperatures colder than 53 °F (12 °C), the coldest launch of the Space Shuttle to date. During this discussion, Lawrence Mulloy, the NASA SRB project manager, said that he did not accept the analysis behind this decision, and demanded to know if Morton Thiokol expected him to wait until April for warmer temperatures. Morton Thiokol employees Robert Lund, the Vice President of Engineering, and Joe Kilminster, the Vice President of the Space Booster Programs, recommended against launching until the temperature was above 53 °F (12 °C).

When the teleconference prepared to hold a recess to allow for private discussion amongst Morton Thiokol management, Allan J. McDonald, Morton Thiokol's Director of the Space Shuttle SRM Project who was sitting at the KSC end of the call, reminded his colleagues in Utah to examine the interaction between delays in the primary O-rings sealing relative to the ability of the secondary O-rings to provide redundant backup, believing this would add enough to the engineering analysis to get Mulloy to stop accusing the engineers of using inconclusive evidence to try and delay the launch. When the call resumed, Morton Thiokol leadership had changed their opinion and stated that the evidence presented on the failure of the O-rings was inconclusive and that there was a substantial margin in the event of a failure or erosion. They stated that their decision was to proceed with the launch.

When McDonald told Mulloy that, as the onsite representative at KSC he would not sign off on the decision, Mulloy demanded that Morton Thiokol provide a signed recommendation to launch; Kilminster confirmed that he would sign it and fax it from Utah immediately, and the teleconference ended. Mulloy called Arnold Aldrich, the NASA Mission Management Team Leader, to discuss the launch decision and weather concerns, but did not mention the O-ring discussion; the two agreed to proceed with the launch.

Dunno about you, but it sounds a lot like NASA, especially Lawrence Mulloy, practically twisted Morton Thiokol's arms until one of them (Joe Kilminster) relented and signed off on the launch. Mulloy even lied by omission at the end there to get his way. I wonder how he could sleep at night after this stunt.