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In Oct. 1968, at North American works, one Oxygen tank was dropped from a height of 2 inches, (perhaps on the fill valve side) and this dropping damaged the fill valve. Because of this, this particular tank could not be emptied completely after the C.D.D.T. tests. But this fact was ignored as one off & trivial. This same tank (with same valve) was eventually used on Apollo 13. If the tank would have been replaced after the C.D.D.T test (on account of its failure to be emptied in given time), could the "FIRE" have been prevented?

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    $\begingroup$ I suggest you rewrite the title to be more specific. $\endgroup$ Oct 18 at 23:20
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    $\begingroup$ @Uhoh: More than 99% of what I ask is based on some reading in official NASA publication. Unfortunately I did not keep a source - track of this particular piece of information. But I understand that its important. Will surely mention the same next time onwards. Thanks. $\endgroup$
    – Niranjan
    Oct 19 at 6:07
  • $\begingroup$ @Niranjan okay, thanks! $\endgroup$
    – uhoh
    Oct 19 at 7:56
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In short yes. But it would have just caused the problem to occur at another time. The drop just cause circumstance that aggravated an existing danger.

The fundamental cause of the fire was due to the shortcut of using 65-volt ground power during the testing of the oxygen tank, despite the tank's mechanisms only being designed and rated for the 28-volt power supply from the CSM they would function under. This overvoltage prevented the thermostatic switches from cutting out the heaters used to boil-off the residual oxygen in the tank.

If that specific tank had not developed a drain problem, possibly due to the drop, then the heaters would still have been used as they were on all the tanks, but the duration would just have been shorter. The normal shorter duration heater use at the incorrect voltage also caused damage to the insulation in the tank wires, just to lesser extent. The added time needed to flush tank#2 which ended up in Apollo13 just ensured that the problem would definitely occur in that tank, not just possibly as for all the other tanks made and tested the same way.

The failure of the oxygen tank on Apollo13 occurred because of the willingness to ignore the voltage requirements for testing, and the willingness to waive a failed test of the tank when it would not drain correctly. But the first is the real cause, the second is merely the trigger.

This is a ridiculously abbreviated version of the timeline of events, of course. For detail, peruse the Report of the Apollo 13 Review Board
The events described by the OP are on page 4-19

To answer the updated question of "Would replacing a damaged tank have prevented the Apollo 13 incident"?
Absolutely yes.
Bearing in mind that that tank was damaged in two completely separate, mostly unrelated ways.
It had some damaged plumbing, preventing a testing drain for completing correctly. This was unique to that specific tank.
And, it had scorched wiring insulation from being tested at incorrect voltages. all the oxygen tanks from that facility had a similar problem.

Fixing both of these would most certainly have prevented the Apollo 13 accident.
Fixing just the plumbing damage on that tank would have... maybe. All the tanks were tested incorrectly, but under normal testing the heater did not reach such a high temperature for so long. The tanks in Apollo 13 might have lasted the mission duration, as the dozens of other tanks from the same line did. Or it might still have failed.

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    $\begingroup$ I agree fully with your this statement. The failure of the oxygen tank on Apollo13 occurred because of the willingness to ignore the voltage requirements for testing, and the willingness to waive a failed test of the tank when it would not drain correctly. But the first is the real cause, the second is merely the trigger. The error on my part is, I posted the question without reading the full text that I was referring to. I have now realized that I should ask the question after gathering all the knowledge possible. Thanks. $\endgroup$
    – Niranjan
    Oct 19 at 6:53
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    $\begingroup$ This second damage then looks more like success as it caused the tank to fail early enough. This lunar module already expended for landing, it would be much worse. $\endgroup$
    – h22
    Oct 19 at 10:06
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    $\begingroup$ @h22 indeed. Not only that, but they lucked out in so many ways, and they had the whole combined intellectual resources of many many experts, and they still came within about 4 hours of running out of enough battery power to initiate reenty. it was close. $\endgroup$ Oct 19 at 13:26
  • $\begingroup$ @PcMan: They could have cut an entire day off return time if they really had to. They actually debated dropping the service module before the PC+2 burn for a fast return. $\endgroup$
    – Joshua
    Oct 19 at 22:53

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