Memorial Emblem, Apollo 1, Challenger {Space_S...
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Dr. Joy Brown, on WOR 710 asking her listeners about their memories of NASA’s space program.  My first thoughts were of the tragedies caused by engineering failures.  Apollo 1, when Gus Grissom, Ed White,  and Roger Chaffee died during a launch simulation.  After the hatches were sealed, the air in the cabin was replaced with pure oxygen. Even though North American Aviation had suggested using an oxygen/nitrogen mixture for Apollo, NASA overruled this. The pure oxygen design carried the benefit of saving weight, by eliminating the need for nitrogen tanks.

The safety of the crew was apparently not high on the list.  After all these astronauts were in fact all test pilots who assumed high risks.

In a BBC documentary NASA: Triumph and Tragedy, Jim McDivitt said that NASA had no idea how 100% oxygen atmosphere would influence burning.  Similar remarks by other astronauts were expressed in the documentary In the Shadow of the Moon. 

The next highlight was the moon landing on July 20, 1968.  Tragedy was averted after  Armstrong took semi-automatic control  during the descent, with Aldrin calling out altitude and velocity data. The  navigation and guidance computer on the Lunar Module, Eagle started displaying program alarms.  The program alarms indicated “executive overflows”, where the guidance computer could not complete all of its tasks in real time and had to postpone some of them.  Neil Armstrong and Buzz Aldrin missed their intended landing site. The computer’s landing target was in a boulder-strewn area.  They landed safely at 20:17 UTC on July 20 with about 25 seconds of fuel left.

Apollo 13’s explosion of an oxygen tank in the Command Module should have been replaced after it failed a preliminary test.  To avoid delaying the mission by replacing the tank, the heater was connected to 65-volt ground power to boil off the oxygen.  A chart recorder on the heater current showed that the heater was not cycling on and off, as it should have been if the thermostat was functioning correctly, but no one noticed it at the time.  Because the temperature sensor could not read higher than 100 °F (38 °C), the monitoring equipment did not register the true temperature inside the tank. The gas evaporated in hours rather than days. The sustained high temperatures melted the Telflon insulation on the fan power supply wires and left them exposed. When the tank was refilled with oxygen, it became a bomb waiting to go off.  During the “cryo stir” procedure, fan power passed through the bare wires which apparently shorted, producing sparks and igniting the Teflon. This in turn boiled liquid oxygen faster than the tank vent could remove it.  NASA, again in its rush to maintain schedule took a gamble by not replacing the tank. 

Luck and NASA’s problem solving by its engineers saved the lives of this crew.

The next disaster was the Space Shuttle Challenger explosion.  A mission that should have been aborted.  NASA managers had known that contractor Morton Thiokol’s design of the solid rocket boosters contained a potentially catastrophic flaw in the O-rings since 1977, but they failed to address it properly. They also disregarded warnings from engineers about the dangers of launching posed by the low temperatures of that morning and had failed to adequately report these technical concerns to their superiors.

Every launch after that day whenever I heard the command, “Go at throttle up.”  I remembered the Challenger explosion.  Seven crew members died.  Francis Scobee, Michael Smith, Elison Onizuka, Jusith Resnik, Ronald McNair, Gregory Jarvis, Christa McAuliffe, the first member in the Teacher in Space Project, died unnecessarily because NASA was  willing to compromise safety in order to maintain schedule.

Although significant changes were made by NASA after the Challenger accident, many commentators have argued that the changes in its management structure and organizational culture were neither deep nor long-lasting. After the Space Shuttle Columbia disaster in 2003, attention once again focused on the attitude of NASA management towards safety issues. The Columbia Accident Investigation Board (CAIB) concluded that NASA had failed to learn many of the lessons of Challenger.  In particular, the agency had not set up a truly independent office for safety oversight; the CAIB felt that in this area, “NASA’s response to the Rogers Commission did not meet the Commission’s intent”.  The CAIB believed that “the causes of the institutional failure responsible for Challenger have not been fixed,” saying that the same “flawed decision making process” that had resulted in the Challenger accident was responsible for a Columbia’s destruction seventeen years later. 

So mostly my memories are of the tragedies that could have been averted if only NASA had thought more of the safety of its crews.  NASA only improved its designs and procedures after failures.