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I am currently reading the gorgeous Folio Society edition of the A Man on the Moon The Voyages of the Apollo Astronauts by Andrew Chaikin (worth a buy from http

I am currently reading the gorgeous Folio Society edition of the A Man on the Moon The Voyages of the Apollo Astronauts by Andrew Chaikin (worth a buy from https://www.foliosociety.com/usa/a-man-on-the-moon.html https://www.foliosociety.com/usa/a-man-on-the-moon.html if you a) like the topic and b) have 235.00). I just finished the book 1 which ends with well known Apollo 13 disaster and the RCA of the explosion is that the liquid O2 tank for the fuel cell was intended for Apollo 10, but was removed for modifications, and during that was dropped about 5cm, a "minor jolt, but enough to damage the tube assembly used to fill and empty the tank". As part of testing - and under full, and capable supervision of NASA astronauts and mission control - the tank was filled and tested, and would refuse to drain fully due to the tube assembly being in the way. Alternative procedure to empty it was to heat it with the internal heater and have the liquid O2 simply evaporate. BUT! The heater inside was originally spec'ed to use 28V, but was upgraded to 65V, and everything in it was redesigned to do so, EXCEPT the thermostat inside the tank itself. The thermostat was supposed to provide temperature control and shut the heating process off if temperatures exceed things. Well, during that ground draining operation the 65V fried the thermostat, and the temp gauge on the ground only went up to 85 degrees. The insides of the tank went up to a 1000, which cracked the insulation on the wires of the motor designed to stir the tank, and those arced while in transit to moon and boom, made that mission what it was. So yeah, space is hard. I am sure the mission people for the lander will do their design review and I look forward to their findings.

xwolfi 3y ago
Space is hard and they had not even left the Earth.
- dredmorbius 3y ago
  Many failures of complex systems originate in fabrication / maintenance rather than in operation. Flights are doomed from the start due to such defects. The Columbia disaster is a partial exception --- the proximate triggering factor occurred during (very early) flight, but a deeper-cause analysis would include factors that originated on the ground in design, operations, and assessments of earlier incidents.
  - jacquesm 3y ago
    And don't forget 'culture', which I think was a huge contributing non-technical factor.
    - dredmorbius 3y ago
      Quite. And also typically occurring on the ground / before the flight. Even where considerations such as crew resource management / cultures of deference (still a factor in recent air incidents, see Asiana 214 in 2013, for example). Which itself encompasses a whole slew of factors: false beliefs, groupthink, politics, cultures of fear (or simply conformity), etc., etc. What I find most interesting about discussions of all of these is that they are so broadly applicable, and are often the parts of incident post morta which are most generalisable to other domains and situations.
asdfman123 3y ago
This all reads like “they were racing to hit deadlines” to me.
- squokko 3y ago
  The Moon landing would have never happened without racing to meet deadlines.
- pjc50 3y ago
  They didn't call the Space Race the "Space leisurely jog". The Kennedy speech really was treated like a deadline.
WalterBright 3y ago
Dropping it 5cm shifted the position of the tube assembly far enough to cause more problems? Why wouldn't that disqualify the part for flight?
- danielodievich 3y ago
  2 pages of the book are dedicated to this. This was reviewed for 2 weeks by dozens of dedicated people, and was signed off by everyone on the mission control and mission commanders. Absolutely fantastic writing and I am sure a distillation of 100s of pages of RCA notes.
  - WalterBright 3y ago
    I bought the version of the book without the pictures for about $3. I'm looking forward to seeing this section.
- KineticLensman 3y ago
  Because the damaged pipe was only IIRC used to drain fuel on the launch pad and had no in-flight role. The subsequent explosion happened because the drain-fuel workaround they used on the ground had the unfortunate side effect of melting some wiring insulation in an oxygen tank
EasyTiger_ 3y ago
[flagged]

xwolfi 3y ago

Space is hard and they had not even left the Earth.

dredmorbius 3y ago
Many failures of complex systems originate in fabrication / maintenance rather than in operation. Flights are doomed from the start due to such defects. The Columbia disaster is a partial exception --- the proximate triggering factor occurred during (very early) flight, but a deeper-cause analysis would include factors that originated on the ground in design, operations, and assessments of earlier incidents.
- jacquesm 3y ago
  And don't forget 'culture', which I think was a huge contributing non-technical factor.
  - dredmorbius 3y ago
    Quite. And also typically occurring on the ground / before the flight. Even where considerations such as crew resource management / cultures of deference (still a factor in recent air incidents, see Asiana 214 in 2013, for example). Which itself encompasses a whole slew of factors: false beliefs, groupthink, politics, cultures of fear (or simply conformity), etc., etc. What I find most interesting about discussions of all of these is that they are so broadly applicable, and are often the parts of incident post morta which are most generalisable to other domains and situations.

asdfman123 3y ago

This all reads like “they were racing to hit deadlines” to me.

squokko 3y ago
The Moon landing would have never happened without racing to meet deadlines.
pjc50 3y ago
They didn't call the Space Race the "Space leisurely jog". The Kennedy speech really was treated like a deadline.

WalterBright 3y ago

Dropping it 5cm shifted the position of the tube assembly far enough to cause more problems? Why wouldn't that disqualify the part for flight?

danielodievich 3y ago
2 pages of the book are dedicated to this. This was reviewed for 2 weeks by dozens of dedicated people, and was signed off by everyone on the mission control and mission commanders. Absolutely fantastic writing and I am sure a distillation of 100s of pages of RCA notes.
- WalterBright 3y ago
  I bought the version of the book without the pictures for about $3. I'm looking forward to seeing this section.
KineticLensman 3y ago
Because the damaged pipe was only IIRC used to drain fuel on the launch pad and had no in-flight role. The subsequent explosion happened because the drain-fuel workaround they used on the ground had the unfortunate side effect of melting some wiring insulation in an oxygen tank

EasyTiger_ 3y ago

[flagged]