Talk:Apollo 13/Archive 2

Copy/paste from Archive 2:

That's pretty much how I'm reading Tdadamemd's comments but they seem to be specific to the word "explosion". Correct me if I'm wrong. Anyway... I dont see an issue with using the word explosion here based on the sources available.--RadioFan (talk) 21:10, 19 June 2011 (UTC)

That was the final comment from the previous discussion on this topic last year. I returned here earlier than I expected immediately after I saw that interview with Chris Kraft last night. That is the biggest significance to the distinction between explosion versus rupture. If it exploded, then there would be a huge question mark as to whether you could use the SPS engine for a Direct Abort to get the crew home quickly. If you understand the systems as being designed specifically to not explode, then you expect damage to be well contained and the SPS engine to be usable, as Chris Kraft expressed that he was clear on.

This is not some trivial semantics debate. Knowing that the tank rupture was not an explosion leads to the understanding that Direct Abort was a perfectly viable option. The article now documents this fact as Chris Kraft's emphatic best choice - which Kranz chose to reject. Kranz maintains that he had a "gut feeling" to not use that engine. This view he has continued to express through the decades gets very curious when you look into his real-time attitude toward the the other pressure vessel that ruptured during this mission. Monitored even before launch, a Supercritical Helium (SHe) tank in the LM's descent stage was known to be overpressured. It was soundly predicted that this tank would rupture some time during the mission, particularly if not used for the landing (which it obviously was not). Kranz could have prevented this tank failure by doing a simple "burp" burn. He chose to simply let the tank pressure continue to rise to the point of rupture. Why is one tank failure, the O2-Tank2 presented as some kind of catastrophic event while the LM SHe tank is treated as so benign that no one chooses an easy procedure that would prevent it from rupturing? It would be excellent to have people like Kranz and Kraft directly asked this. What is perfectly clear from references we do have available is that the Flight Director post-mission report from April 1970, signed by Kranz which Kraft would have given input to and reviewed as well, never stated a single time that there was any explosion of any kind throughout the entire mission. Not the O2-Tank2. Not the LM-SHe tank. There was no conclusion of an explosion, and now there is an excellent reference where Kraft makes it explicitly clear that Direct Abort was perfectly viable.--Tdadamemd (talk) 20:16, 17 January 2012 (UTC)

The April 1970 report make clear that it is reporting "Apollo 13 flight operation as seen in real time." They did not know exactly what happened. What they did know included a reported "loud bang", the sudden loss of pressure in one O2 tank, slow loss in the second, two fuel cells out, etc. That's not a "one tank failure" as you put it, but multple system failures for reasons that were not clear at the time, more than enough reason to lose confidence in the SPS. But even if the SPS were trustworthy a direct abort was problematic, as the the report's summary states "A direct return to earth with a landing time of 118 hours GET was possible only by using the Service Module propulsion system and jettisoning the LM. This option was unavailable for obvious reasons..." --agr (talk) 00:50, 18 January 2012 (UTC)

Besides which; even if they wanted to fire the SPS they had the slight problem of there being NO oxygen available to fire it! As all the spacecraft oxygen systems were independent and self-contained (Except for the SM which supplies oxygen to the CM during spaceflight) there was no way to use the LM's LOX to fire the engine and without the advanced space repair techniques of today there would have been no way to repair the LOX tanks of the SM so that the SPS could be fired (I think that even today an in-space LOX tank repair is impossible!) Barts1a / What did I actually do right? / What did I do wrong this time? 00:58, 18 January 2012 (UTC)

Umm, I think you are confused here. The SPS did not use LOX. All of the rockets and thrusters on the CM, SM and both LM stages used nitrogen tetroxide as oxidizer. The rockets used Aerozine 50 as fuel, thrusters used mono-methyl hydrazine. (The fuel and oxidizer ignite on contact, making propulsion systems much simpler.) On the broader question, I think some editing of the article is in order based on what the April 1970 report says about direct abort. After the anti-SOPA blackout... --agr (talk) 03:24, 18 January 2012 (UTC)

You're right... I was thinking of the more modern SSME... However the "explosion" may have caused the engine bell to crack due to the impact of the panel that was blown off and/or blast damage (Directly quoting the astronauts here: "Think it zinged the bell huh?" (said very soon after the SM was jettisoned) and there were scorch-marks on the engine as visible on the image in the article). And a cracked combustion chamber is not good news in ANY engine! Barts1a / What did I actually do right? / What did I do wrong this time? 09:02, 19 January 2012 (UTC)

Tdadamemd, can you please provide a link to the interview you're referring to, and possibly a pertinent quote? Thanks. Yopienso (talk) 08:42, 19 January 2012 (UTC)

If my post from yesterday (below) did not answer your question, please let me know. And Barts1a, as for the idea that any part of the SPS was damaged, I'll re-highlight this quote from the A13 Mission Ops Report:

"There is no data indicating damage to the SPS as a result of the O2 tank fracture." (pg F-2 / pdf-pg195of345)

It is clear that there were key people who believed that a Direct Abort was the best option.--Tdadamemd (talk) 08:41, 26 January 2012 (UTC)

Actually, I think we've flogged this dead horse enough. The official NASA site calls the incident an explosion and a rupture; my bolding and underlining here:

• "There's one whole side of that spacecraft missing", Jim Lovell said as the Apollo 13 astronauts got their first view of the damage that had been caused by the explosion.
• The Service Module was towed all the way back to Earth after the explosion in order to protect the Command Module heat shield.
• The Apollo 13 malfunction was caused by an explosion and rupture of oxygen tank no. 2 in the service module. The explosion ruptured a line or damaged a valve in the no. 1 oxygen tank, causing it to lose oxygen rapidly. The service module bay no.4 cover was blown off.
• This fire rapidly heated and increased the pressure of the oxygen inside the tank, and may have spread along the wires to the electrical conduit in the side of the tank, which weakened and ruptured under the pressure, causing the no. 2 oxygen tank to explode. Yopienso (talk) 09:05, 19 January 2012 (UTC)

Tdadamemd is correct that the reasons given in our article for not choosing direct abort needed revision. I've done this based on what was said in the mission ops report of April 1970, with page references. --agr (talk) 19:47, 19 January 2012 (UTC)

OK, everything looks great; thanks to all. I'm just tucking these links in here in case we need them later. Cortright 3 times calling the explosion an explosion in a 1998 interview. A discussion of why a direct abort wouldn't have worked. Yopienso (talk) 18:13, 20 January 2012 (UTC)

Hello all. Excellent discussion here. I'm going to reply down here, and then later go back up to other replies to clean up stuff I missed.

To recap the basic issues here... Was the incident an explosion? Then... How does the answer to that first question impact the abort options available?

Thanks, Yop, for that Cortright Oral History. I found it fascinating (for many topics outside of A13 as well). So Cortright in the late 90's is unequivocally calling the incident an explosion (as you said, 3 times he calls it that). Is this reference changing the picture at all? What it does is it puts Cortright firmly in the ranks of people like Kranz, Kraft, Liebergot, etc. People who all wrote detailed official reports in 1970 after the mission where they never call the incident an explosion. Then for whatever reason, years later they are near-ubiquitous in their use of describing it as an explosion.

How freakin strange. Ed Cortright signs off on the official investigation report. That document never describes the O2 Tank 2 failure as an explosion in any of its hundreds of pages (that I've yet been able to find). Then he sits down years later for this oral thing, the topic comes up and within TWO pages of transcript he calls it an explosion. Then within the next page or two he calls it an explosion two more times! Edgar had the opportunity to say this, if that's what he really believes, way back in 1970. It is very strange to know how people's stories have changed. These are people who know (or knew) in exacting detail how these tanks had been designed with multiple safety mechanisms to not explode.

Almost two years ago here, I went through one of the reports with a fine tooth comb to ferret out exactly the terminology that was used in describing the event. I picked the Mission Operations Report for a very specific reason: It was authored by many different experts who were closely involved with the mission. Their signatures were right there, scanned into the pdf. Gene Kranz, Glynn Lunney, Seymour Liebergot, John Aaron, Jim McDivitt, and many more.

Not a single one of them called the incident an "explosion". I'll repost here the exact words they did use (cut&paste from Archive 1):

__________

Ok, in case there is any lingering question regarding the persistent notion that the O2 tank exploded, I just scoured the entire Mission Operations Report that was published at the end of April 1970 (separate from the Cortright Report). This is a 345-page document that is a compilation of different reports submitted by various groups within Mission Control, from the Flight Directors on down. I read through the entire report and found these totals for how the O2 tank 2 event was described:

• "Anomaly" (/anomalies) - used 19 times.
• "Rupture" (/tank rupture, etc) - used 6 times: pgs F-1, F-4 (x2), F-7 (x2), and E-17 in the EECOM report signed by Sy Liebergot.
• "Accident" - used 6 times.
• "Incident" - used 5 times: all on pg 7-3.
• "Loss/lost" - used 5 times.
• "Failure" (/near catastrophic failure) - used 3 times.
• "Problem" - used 3 times.
• "Contingency" - used 3 times.
• "Shock" - used 1 time: on pg F-1.
• "Systems situation" - used 1 time: on pg II-1.
• "Explosion" (Exploded/Explosive/etc) - used ZERO times.

Now it is certainly possible that my count is off. Anyone can check it for themselves. But the pattern is clear.
__________

In the past week, I looked through that document again and noticed that I had missed this:

• "There is no data indicating damage to the SPS as a result of the O2 tank fracture." (pg F-2 / pdf-pg195of345)

If any of the authors of this section (signed by 4 GNCs) believed that the incident was an explosion, and that the explosion gave them concern that the SPS might not be reliable, they NEVER communicate that in their report.

I've now taken the further step of scrubbing through the entire Apollo 13 Mission Report (not to be confused with the Mission Operations Report above). The first thing I'd like to say about it is that it gives the best description of the event that I've ever read anywhere. It's in Section 14, the Anomaly Summary. That description starts at the bottom of pg110of168 in that pdf file, then continues into the beginning of the next page (p14-2).

As you all might guess, nowhere in that entire description is the event described as an explosion. I've gone through every single page of that report and not one single place that I could find was it ever described as an explosion. I'll share the results here:

______

• "incident" (/tank incident /cryogenic oxygen incident /"emergency incident" p9-2 /"inflight incident" p9-2&p9-4) p7-3Chg1(x5), p1-1, p3-1, p3-2, p4-4, p5-2, p5-4, p5-6, p5-9, p5-11, p6-1, p6-4, p7-1(x5), p7-2, p7-3(x5), p7-5, p8-4, p8-8, p9-1, p9-2(x3), p9-3(x3), p9-4, p9-5, pA-6

• "the emergency" p10-2, p15-1

• "pressure decay...essentially instantaneous" p7-3Chg1, p7-3

• "loss/lost" ("abrupt loss of...cryogenic oxygen associated with a fire" p1-1 /"the tank abruptly lost pressure" p1-1 /"sudden loss of pressure" p3-1&p5-2 /"oxygen tank pressure loss" p5-4&p5-11 /"total loss of primary oxygen" p15-1 /"loss of pressure integrity" p15-1 /"cryogenic oxygen loss" pdf168of168) p1-1(x3total), p3-1, p5-2(x3), p5-4, p5-11, p14-1, p15-1(x2), pdf168of168

• "anomaly" (/tank anomaly) p2-1(x2), p3-3, p5-6, p5-11(x3), p6-2, p10-7, p14-3(x3)

• "damaged bay 4 area" p3-3

• "pressure excursions" p5-2

• "pressure...dropped" (/"pressure was zero" p8-9 /"pressure decreased...momentary pressure increase" p14-1) p5-2(x2), p5-3, p8-9, p14-1(x2)

• "degradation" p5-2

• "inflight failure" p5-3

• "inflight shorting and rapid oxydation" p15-1

• "noise" (/loud noise /"the noise" p14-1) p8-8(x2), p14-1

• "minor vibration or tremor" p8-8

• "a vibration disturbance" p14-1

• "the crew heard and felt the vibrations from a sharp "bang,"..." p14-1

• "a transient had occurred" [in the electrical system] p8-8

• "venting" p8-9

• "oxygen depletion" p8-9

• "such contingencies" p8-11

• "a problem" p10-1

• "causing the tank line to burst because of overheating" p14-2

• "ruptured electrical conduit caused the vacuum jacket to overpressurize" p14-2

• "caused the blow-out plug in the vacuum jacket to rupture." p14-2

• "possibly the burning of insulation in bay 4 combined with oxygen buildup in that bay, caused a rapid pressure rise which resulted in separation of the outer panel." p14-2

• "tank rupture." p14-2

• "panel separation shock" p14-2

• "structural failure of the tank" p14-2 [referring to design changes so that this won't happen on future missions]
  

______

The publication date on that Mission Report is September 1970. The Mission Ops Report has a much fresher publication date of April 28, 1970 - the very same month of the "explosion".

There is nothing new in this angle I'm presenting. It's now just at a more thorough level. Someone might want to do this with the entire Cortright Report to quantify precisely what I know from having read it. None of these official reports call the O2 Tank 2 failure an "explosion".

It is clear to me that what we have here is a case of the story being told one way at this particular frame of time, 1970, by many of the people involved. Then after 1970, the story changes!

The most substantial rebuttal I have gotten to date has been Yopienso's view that for some reason these official reports wanted to avoid using the term 'explosion' as being too colloquial, or something to that effect. (The exact rebuttal should still be available in the archives.)

...but in reading through that Mission Report, it became clear to me that this rebuttal doesn't hold water because the report DOES use the word 'explosion' specifically, more than once. Here's where:

• on p11-10: Describing TNT explosion energy equivalent in the S-IVB impact into the Moon. (Absolutely nothing to do with the O2 Tank 2 failure.)

• and again on p14-29: "The accompanying "explosion" would then blow off or rupture the seal of the battery lid..."

This last mention is describing a failure mode of a LM descent battery when electrolyte leaks causing oxygen and hydrogen gas to accumulate under the battery lid and then combusting. The crew had "reported a thumping noise and snowflakes venting" from the LM. This report identified the phenomenon, explaining the cause. The electrolyte gas combustion caused the "explosion" thump as well as the "snowflakes". This report put both of those terms in quotes, meaning that the phenomenon was not exactly an explosion nor did it exactly produce snowflakes, but something similar enough to associate the event with those words.

With the O2 Tank 2 failure, the crew reported hearing a thump (on par with Haise's depress valve pranking) and they see something venting overboard. This report (and the others) describe the failure mode in detail, never once using the word 'explosion' (not even in "quotes"). But in explaining the LM battery thump, the report specifically uses the word "explosion" (albeit in quotes).

With no further facts presented here, I suggest that we work toward a consensus that it would be proper for the article to reflect the original story (not an explosion) and then also cover how the incident is now commonly referred to as an explosion. This had been suggested years ago, and now that there appear to be a core of editors who are thoroughly knowledgeable on the incident, we can now have a meaningful vote for consensus.--Tdadamemd (talk) 06:07, 24 January 2012 (UTC)

I feel certain the story has not changed a whit. The Cortright Report was written in officialese and the interview was conducted in plain English. All the words and phrases you've quoted above boil down to "explosion," but Cortright used the proper technical terms in his written report, just like a coroner would record a death was due to "myocardial infarction" or "coronary thrombosis," but would never disagree with the decedent's family that he had died of a "heart attack."

I believe it's time for us to agree that a rupture that occurred due to over-pressurization and resulted in crippling structural damage can safely be termed "an explosion." Please see points 7 and 8 at WP:NOTMANUAL. Failing to use the word "explosion" will result in just your confusion for other lay readers who may not realize that the technical terms mean "explosion." Yopienso (talk) 02:06, 25 January 2012 (UTC)

Yopienso, I have to disagree with you on a number of points here. You are correct to refer to the event as a "rupture that occurred due to over-pressurization", but INCORRECT to call it "an explosion". 'Rupture' and 'explosion' are two completely different things. If I over-inflate a rubber balloon and it bursts, could I say that the balloon exploded? No of course not - and that is the same as what happened to the O2 tank on Apollo 13.

It's simply factually wrong to call the event an explosion. The only words that are appropriate are 'rupture', 'burst', etc., just as other editors above have also said. These are everyday and commonly understood words, not technical terms that only academics understand, therefore WP:NOTMANUAL doesn't apply to this issue. Can I suggest that we add a comment to the article along the lines of "although the incident is often refered to as an explosion, it was actually a rupture caused by over-pressurization" Logicman1966 (talk) 00:56, 26 January 2012 (UTC)

I have disagreed with that assessment at length. We have multiple references that quote the astronauts themselves, as well as Cortwright and NASA, calling it an explosion. If it were inappropriate to call it so, I don't think they would have. In fact, in a non-technical context, that is their word of choice.

Tdadamend has persisted in using a primary source. Read this and this and this and countless more secondary and tertiary sources, which is what WP is supposed to use. Yopienso (talk) 01:57, 26 January 2012 (UTC)

Cortright's report is crystal clear on the distinction between what an explosion is and what an explosion isn't. It provides a wealth of detail regarding the failure mode of the tank system. Board members were eye-witnesses to tank failure tests that were done at MSC. It's all documented. Here are selected excerpts:

Cortright-AppendixD, pD-78: "The pressure vessels are of concern in that they represent large energy sources in the event of their catastrophic failure. Qualification records were reviewed and analyzed to determine the actual factors of safety demonstrated by burst test, as well as the characteristics of the failure modes. The failure modes of the pressure vessels have been categorized as explosive, uncertain, and benign. With these data, an assessment was made of those components that might be damaged by the explosion of a tank and the effect of this explosion on the vehicle systems and the crew."

pD-83: "The explosive failure of a pressure vessel on the spacecraft, depending upon the energy stored in the vessel, could result in effects ranging from localized damage to loss of spacecraft and crew. The following approaches were considered to provide protection to the spacecraft and crew from the catastrophic explosion of a major pressure vessel: ..."

-Clearly the authors are well aware of what an explosion is. Then contrast that above language with the stark absence of the term when describing the O2 Tank 2 failure.

pD-21 - Summarizing the results of the O2 tank overpressure burst testing done four times: "All ruptures were similar... In no case was there violent fragmentation."

pF-48 - Full-Scale Simulated Oxygen Tank Fire (1g) The tank itself never fails. It is the conduit that ruptures. No explosion whatsoever. Just two-phase (liquid & gaseous O2) venting flow through an area in the broken conduit line of about one-half inch in diameter.

Look at the post-test photo on pF-50 and decide if that's the remnants of a violent explosion. It looks near-pristine.

The photos on pF-52 and F-53 are closeups of the failed conduit.

pF-61: Various combinations of calculations based on the expected conduit breach hole size "do not predict pressures in excess of 20 psia". This would lead to a conclusion that the pressure that caused the SM panel to blow off was far less than the pressure inside your average car tire.

It goes on to speculate that there may have been other factors that possibly could have caused a higher peak pressure, or that liquid O2 "flashing to vapor might produce a strong pressure pulse".

(Panel separation test on pF70-F82.)

pF-100: "Fracture Test on Oxygen Tank" - "Test shows that the failure mode of the tank would have probably been leaking and not a rupture."

pF-102: "...Panel Separation Test" - "Peak pressures that occur in the oxygen shelf space are near 50 psia, 25 psia in fuel cell shelf, and somewhat less than 10 psia in tunnel volume." --These pressures, peak or even steady, if pumped into your car tire are not strong enough to blow it off the rim.

pF-120 Fault Tree Analysis: "chemical reaction damage" > "hole occurs in conduit" > "O2 leakage thru connector conduit" > "loss of O2 due to failure of ancillary lines"

These are smart people who wrote the report. They know what an explosion is. They thoroughly analyzed the situation, put together theories, then verified with numerous experiments. The reason why the report never calls the event an explosion is because their analysis and testing determined that the most likely scenario was that the spherical tank itself never cracked. It was the conduit coming out of it that sprung a small hole and the contents of the tank spewed out. I've stated this clearly here before (see archives) in comparing a firecracker that explodes to a firecracker that is split in half before lighting it. The expanding combustible gases can now easily escape and the firecracker does not explode. It just fizzles. What happened on Apollo 13 is that the O2 System 2 overpressurized, the conduit ruptured, and the contents "fizzled" (my word).

A very similar thing happened in the LM DPS Supercritical He tank. It overpressurized, the designed in safeties worked as planned, and those contents "fizzled" as well. The primary difference between the two is that the O2 system failure had additional energy from the combustion (but there was very little with regards to combustible material inside that tank).

The third anomaly that was reported on was the 'thump' that the crew heard with the associated battery spike. It was determined that the LM battery electrolytes had leaked, the O2 gas reacted with the H2 gas, and this combustion blew off the battery lid. This is the ONLY one of the three incidents that any of the reports describe as an explosion. And when that word is used, it is put in "quotes".--Tdadamemd (talk) 09:08, 26 January 2012 (UTC)

OK, one question at a time: How, then, did this happen? Yopienso (talk) 15:08, 26 January 2012 (UTC)

You posted that with the Edit Summary comment "Please explain how a gentle fizzle wreaked such havoc". Let's be clear that no one is saying that the rupture was gentle. The system blew at over 1000 psi. Hardly a friendly environment to be around. And the contents vented into a closed volume (sector of the SM).

How exactly this happened, Cortright's report again provides a wealth of detail. They got the best understanding of how the panel blew off when they did half-scale testing at Langley. The volumes were modeled, and the O2 venting was modeled. They'd tweak the parameters in a number of repeated tests until their results gave a close match of what the crew saw in that photo - the entire panel got blown off. This is all detailed in the Appendix that I cited in my previous post above: "(Panel separation test on pF70-F82.)"

Now here's what you might find to be the most interesting... When they applied a large pressure pulse, in what might be more expected of an explosion, the panel did not separate. What happened was that a hole got punched through the SM wall. The way they were able to get the entire panel to separate was through a more gradual pressure rise - consistent with the conduit rupture and subsequent venting (or spewing) through the small hole - so that a more even pressure was applied to the entire panel. And it wasn't all that much pressure that it took to do this. Again, it was on par with the level of pressure that can easily be held in your car tire. Instead of me explaining this in my words, here's how Cortright himself explained it in a press conference:

pH-33: Cortright press briefing, June 2nd -

"The first thing that was found out was that if you pulse a very rapid pulse in a local area, which simulated a very rapid, rather large rupture of the tank, it tore a hole in the panel. But if the pulse were just a little bit slower and gave sufficient time fot the gas to spread throughout the whole bay and pressurized that panel fairly uniformly, it came off completely, and it came off at about the pressure it was designed for, which was between 20 and 25 psi."

Cortright's team was extremely thorough in explaining the precise mode of failure and the exact reasons why this all happened. Very curious that he knew all this at one point in time, and then in the late 90s he casually calls the event an explosion! My best take on that is that he's rolled over and given up on educating the public about the difference. So many people, from Lovell to Liebergot to Ron Howard had thoroughly embraced the romantic notion that the crew survived a near-fatal explosion. My specuation there. It would be much better to ask Cortright directly, ideally by showing him a copy of his very own report.--Tdadamemd (talk) 18:15, 26 January 2012 (UTC)

Thanks. I'm leaving for several hours, so will ask my next question before responding to your long and detailed answer. Forthwith: Why do you use one technical report to rebut what dozens of thoroughly reliable sources--all the broadcasters and newspapers and several books--have published since 1970 to the present? The Cortright Report is the odd one out, and even it admits, "The relatively sudden, and possibly violent, event associated with loss of integrity of the oxygen tank no. 2 system could have ruptured a lineto oxygen tank no. l, or have caused a valve to leak because of mechanical shock." Yopienso (talk) 18:29, 26 January 2012 (UTC)

Let's be very clear that this is not just one report standing alone against all other reliable sources. It is all three official reports that were released in 1970. In the order they were released, those were the Mission Operations Report, the Cortright Report and then in September the Mission Report. None of them call the event an explosion, with the one exception of the one single case I cited below of Ed talking to reporters in late April when he was on the job for a whole 3 days. After that, the closest any of those reports ever gets to calling it an explosion is in that quote you've just posted. I highlighted that one many years ago, because that was the most I could find. And that statement is well short of calling it an explosion.

So what we have is three thick official reports that say one thing, and then after that we hear the story told a different way. The most curious part is that it is some of the very same people who wrote those reports who are changing their story. One of the most emphatic is Sy Liebergot. Once the story morphs into "an explosion", the tale shifts to something that was out of their control to which only their valient effort leads to the survival of the crew. It is no longer the story of a string of Mission Control mistakes where if a front room EECOM, or someone in the backroom, had noticed the pressure rising in the O2 Tank 2 they could easily have followed the checklist procedure of opening the pressure relief valve and de-energizing the electrical circuitry within the tank. Lovell and Haise would have gotten their moonwalk.

It is Lovell who is the first person who unequivocally calls the event an explosion. He clearly says it on the real-time audio tape. His crewmate Haise is much more cautious in his terminology during that same conversation. But in the post-mission crew debrief, Lovell sticks to his version of what happened, even though he is way short on evidence and facts. I've offered an explanation in years past on the reason behind this. The man had been to the Moon twice. He lost it. His dream was shattered, and one way of coping with that loss was to fabricate a belief that the tank exploded and he was lucky to be alive. How do you live with the knowledge that it was the bungling EECOM team that failed to monitor their systems properly that prevented you from becoming the fifth man to step foot on the Moon? That's my best guess as to why Lovell stuck to the explosion story, and it caught on like wildfire. It was a convenient out for Liebergot. It made Kranz look like a hero. And it sure provided a good drama for Ron Howard to sell tickets to his movie.

My speculations above are well outside of what we are here at Wikipedia to accomplish, so I'll stop there. What we are here to do is create an article that presents the facts of Apollo 13 as is best known. And as the article stands today, it does a poor job of communicating the wealth of information that Cortright and those other two reports have provided to us.--Tdadamemd (talk) 19:13, 26 January 2012 (UTC)

EUREKA! I found the one place that Cortright's report calls the incident an explosion! It comes from the mouth of Ed Cortright himself. He is giving a press conference on April 24, one week after splashdown, just three days after the board's first meeting.

pH-10: Ed Cortright - "...the short period of time in which the apparent explosion took place..."

He is totally fresh on the subject, and he is careful to caveat the term as "apparent". He never calls it that ever again in the report (that I have yet found) as he obviously becomes far more informed on exactly what happened. In that same section I also found a few cases of where the reporters ask questions that refer to the event as an explosion. But this is only coming from the reporter side of the discussion. I found these three cases - on pH-23, H-35 and H-37. One could argue that it was the Board's duty to correct the reporters, but the exact failure mode was still in the process of being determined.--Tdadamemd (talk) 18:35, 26 January 2012 (UTC)

I had started today to go over this point by point with you, but realize there really and truly is no reason to keep flogging this dead horse. Unimpeachable sources call the event, incident, anomaly, failure, an explosion. The article correctly reflects this mainstream consensus.

Because you are interested in this subject, I'll link to a book by Lovell and a helper. You would enjoy searching "explosion" and "Kraft" in it. The most reliable source I'm aware of is this one.

It seems you espouse a conspiracy theory that suggests: 1. There was no explosion. 2. The crew could have been brought back safely without going around the moon. If you have reliable sources for these ideas (I haven't found any.), you could open a controversy or conspiracy section of the article. If they are you own speculations, remember WP:OR.

I did have one more question: What made that loud bang that shook the whole ship? Yopienso (talk) 21:00, 26 January 2012 (UTC)

The plain fact of the O2 System 2 failure mode is not some conspiracy. It happens to be the official NASA position. All I did was bother to read the reports they published. Never once in any of those three reports do they present a conclusion that it was an explosion.

What caused the BANG? The short caused combustion which caused the overpressure which caused the conduit to rupture which caused the two-phase venting into the SM sector which caused the external panel to separate. There's your bang.--Tdadamemd (talk) 21:56, 26 January 2012 (UTC)

...as for the reliable source for Point 2, I posted that along with the video of the quote:

Chris Kraft stated:

"The thing that I wanted to do ASAP was fire that damn [SPS] engine. If we had been able to do that we could have turned around and had them landed in about 15 hours."^[8]

You promptly wiped that out, as you persist in wiping out many important facts from this article.--Tdadamemd (talk) 22:14, 26 January 2012 (UTC)

What did I wipe out? I watched that YouTube clip three times. You must misunderstand IF WE HAD BEEN ABLE TO. He did not say, "If Kranz would have listened to me." Read Kranz's words about it here, on pp. 317-318; Kraft agreed with Kranz. Lovell/Kluger say exactly the same thing here on p. 144.

I'll keep watching the article but will not continue this ceaseless argument. Yopienso (talk) 23:18, 26 January 2012 (UTC)

Page 318 of Kranz's book: "I believed that the systems controllers thought I had made the wrong decision. They favored the fastest way home, a direct abort." This is exactly the same sentiment Kraft expressed in that video I had posted. It is totally obvious that they were able to do a Direct Abort if that had been their choice, particularly in Kranz's own words immediately following Kraft in that video. Had there been any physical impossibility that would have prevented a Direct Abort, then there would be no reason for Kranz to explain that it was his "gut feeling" that led him to not do a Direct Abort.

I fail to see where Kranz explicitly states that Kraft believed the circumlunar abort to be the smartest. The best I saw was where it said that Kraft nodded his head. A head nod can mean a lot of things, such as "I hear you", or "I understand what you see to be the smartest choice".

As for the Lovell-Kluger book, it certainly is much more explicit. It presents various unrecorded private conversations as plain fact. I hope everyone is clear that Jim Lovell was not there as a first-hand witness to these conversations. Lovell was busy flying in a spacecraft nearly a quarter of a million miles away. Kluger was not there either. The very best this book is presenting is hearsay, unless there was a ghost writer where one of the people in one of the conversations wrote that section of their book.

A much better source for determining what Kraft's position was is Kraft himself. Oddly enough, Kraft's book says near-nothing about his thoughts on the abort trajectory decision. It's obvious to me that the best source regarding Kraft's position is the video of Kraft emphatically stating what he saw to be the best option.

...back to Kranz's book. On page 324 he says, "The last thing we wanted to do was let the brass think there was any real disagreement in our group or uncertainty about our recommendations." He's explicitly stating how the story that a person presents does not always match the actual facts of the story. Historians are well aware of this, which is why there are historians - to help get to the bottom of things by weeding out the bogus info from the verified facts.

That video of Kraft is a very important part of the Apollo 13 story. It is clear to me that deleting it from the article is a mistake.--Tdadamemd (talk) 08:02, 27 January 2012 (UTC)

Oh, now I see what you were referring to by "wiped out." If you want Kraft inserted, please include a note that he stated years later, and, instead of suggesting a showdown such as this wording suggests, Others discounted the direct abort option for the following reasons, say something to the effect that the direct abort was not feasible for the following reasons. Kraft wished they could bring the crew straight home, but agreed with the consensus that there were compelling reasons to opt for the circumlunar abort. (Not to say he wouldn't have opted for the direct abort had he been the decision-maker, but he was no longer #1, and he, from all I can find, worked well with the others. The consensus today is that the longer path was the wiser path, but of course, we'll never know. We do know they were all shocked to discover how severely damaged the ship was.) YouTube, by the way, must be used with care as a source. WP:NOYT.— Preceding unsigned comment added by Yopienso (talk • contribs) 10:07, 27 January 2012‎ (UTC)

> "...say something to the effect that the direct abort was not feasible for the following reasons."

That actually goes against the point I was trying to make. Everything I've read indicates to me that the Direct Abort was totally feasible. Kranz had a gut feeling to not burn the SPS. Other controllers saw this as a mistake. I'm very glad to have Gene paint what might be the most complete picture we have documented on the abort mode decision. The best the article can do, as I see it, is to gather the best info from various sources and then summarize it. I am certain that a Direct Abort could have been accomplished while still keeping the LM Ascent Stage as the lifeboat. It may take some poking around for me to re-find the proper source. That info may very well be in the table that Arnold Reinhold was referring to. I look forward to his reply in the section above.

> "The consensus today is that the longer path was the wiser path, but of course, we'll never know."

The story of Apollo 13 is a story of brilliant success in bringing home all three astronauts in one piece. I have deep admiration for what all of them accomplished. The part of the story that has gotten dropped from what the official reports have told us is that MCC painted themselves into that corner (which they then boldly got themselves out of). Primary points:

- Kranz's book talks about how "after considerable debate" they "did not reset the alarm". This alarm would have alerted Liebergot that the O2 Tank 2 pressure was rising and that he could have taken action to mitigate or prevent the subsequent overpressure rupture. This was simple checklist procedure that had been exercised in training simulations.
- Knowing that they had made that decision to not reset the Master Alarm, the EECOMs in the front room as well as the back room should have been extra vigilant in monitoring their parameters. They all missed it.
- Then there is the abort mode decision. The strongest argument against the Direct Abort was concern whether the SPS was reliable. But the RCS system has far more plumbing, and if that system was working then it would point toward the internal aspects of the SPS being ok (along with direct sensor readings). As for the external aspects of the SPS, the best indicator there is that the High Gain antenna ended up working ok. Being far more delicate and exposed than the SPS external components, this would point toward the entire SPS being ok. Deciding to take the longer route around the Moon painted them tightly into the consumables corner.

> "We do know they were all shocked to discover how severely damaged the ship was."

I totally disagree with that statement.

Yes, the panel was blown off. But the Cortright quote I had posted above makes it clear that it was designed to do that. He said, "it came off at about the pressure it was designed for, which was between 20 and 25 psi."

A much bigger problem would have happened if the pressure built up inside the SM and the panel did not blow off. Kinda like the pain you feel from holding in a burp. The panel blowing off (per design) actually helped to relieve the situation. Years ago on a Usenet forum, I presented that view as my best guess. I was very glad to find this quote to confirm that this week.

What the report told us (best I remember) is that the post-jettison photos of the SM were thoroughly analyzed and it was inconclusive as to whether any damage to the SPS could be seen.

And the point I made years back was that blowing an SM panel off into space was a perfectly normal procedure that was done on the last three (totally successful) lunar landing missions. A photo of a blown off panel, in and of itself, does not necessarily mean that the ship is severely damaged. It can mean that the ship is in perfectly normal condition. Again I offer this photo as a case in point. Blown SM panel. Successful Moon landing mission. The A13 SM was damaged, of course. But that infamous photo, for those who have this full understanding that I've highlighted, the photo serves to confirm how damage was mitigated because the panel did blow off as it was designed to.

Another major point you have wiped from the article was this:

"Rupture disks and other safety measures were present to prevent a catastrophic explosion, and analysis of pressure readings and subsequent ground-testing determined that these safety measures worked as designed."

The Cortright report gives detailed info about these various safety measures. It says (as I've quoted above) how pressure vessels have the potential to explode. It also gives detailed test results that show how the O2 Tank and conduit did not explode, verified in repeated testing.

The reason you posted for your delete was "If they had "worked as designed," the flight would not have been aborted."

I hope you realize that what Cortright was telling us is that if these safety features didn't work per design, the crew would have been killed right then and there. What would have floated around the Moon would have been a debris field that included their lifeless bodies.

The article will be improved if that statement gets re-added.--Tdadamemd (talk) 06:55, 28 January 2012 (UTC)

Here's a quote from Henry Cooper's 1972 book, 13: THE FLIGHT THAT FAILED (p21, emphasis by Cooper):

...the resulting gases blew out the bay's cover, which was one of the six panels making up the service module's external hull. It was lucky the panel blew out when it did, for if the pressure had been allowed to build up much more, the command module itself, plugging the front end of the service module like a cork, could have blown off instead. Later, in describing what happened, NASA engineers avoided using the word "explosion;" they preferred the more delicate and less dramatic term "tank failure," and in a sense it was the more accurate expression, inasmuch as the tank did not explode in the way a bomb does but broke open under pressure.

That author put together a better-researched book than almost any that have been published in the decades after.--Tdadamemd (talk) 16:05, 1 February 2012 (UTC)

AMEN!!! That's what I've been saying: The engineers purposefully avoided using the word "explosion;" they preferred the more delicate and less dramatic term "tank failure,". Now, you have probably latched onto Cooper's comment with the interpretation, "AMEN!!! that's what I've been saying: the tank did not explode." But you must notice he qualifies that with in a sense. In every practical sense, the tank blew up: it exploded.

I was sorry to see you going on again about the panel being designed to blow off. That was only in an emergency and was not at all the same at the deliberate blow off in subsequent missions. Look at the picture of the damage to Apollo 13!! Then compare it to the picture you linked to. No comparison, and you shouldn't try to make one. Certainly it was far better for the side to blow off than for the whole ship to blow to bits! Yopienso (talk) 20:45, 1 February 2012 (UTC)