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Kids trapped in a cave 25

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3DDave

Aerospace
May 23, 2013
10,685
Not a result of engineering, but one that might benefit from it.

The kids soccer team is trapped in a cave. From the graphic on the news it seems there are several pools that have sealed off the exit path. The children are supposed to be unable to swim, though I don't know that that is a special limitation. More concerning is that using scuba equipment might be too complicated for them; not only are they not familiar with it, the water they will move through is so murky that they would essentially be blind, deaf, and unable to communicate so that even guides would be unable to help them escape.

There is no immediate problem for them; they are now supplied with food and water and medical care. They have been without food for a week and will take a while to recover from that.

However, there is no known time at which the water will recede from the cave. I expect that there is insufficient pumping capacity to offset the rate at which it can be replenished. On the news they estimated weeks to months before the cave might dry enough.

Since they are in the cave, the passage was certainly large enough to get in and so there should still be enough room to get out. In particular full-sized adults have made the journey.

A thought occurs to me that it should be possible to pull corrugated tubes through each of the pools and then pump those out. If the ends are above water, there should be no replenishment beyond minor leaks for the pumps to offset. Using these the children should be able to crawl out, and will have light and audible communications to guide them.

The water is apparently only 16 feet deep at most, so the pressure can't exceed 8 psi. Anchorage will be required to keep it from shortening axially, but that should be a few hundred pounds to be useful.

I would estimate that a 24 inch diameter would be enough. I'm thinking of construction as is used for ventilating manholes, possibly with stronger wire.

If the tube obstructs the path for the adults, then they can wait the few days while the tubes are placed, the children escape, and then the tubes can be retrieved. If they are anchored against the cave roof by buoyant forces, they can be flooded again and then pulled back out.


Does this seem like a feasible way out?
 
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Hi Dave'
Are you working for Musk on his PR spin team?
You post a link to this site: /6743086/british-thai... :
"that is independent of the CNN interview" look here: /6792661/who-vernon-u...

What part of ELON MUSK'S SLUR WAS AND IS UNACCEPTABLE do you not understand?
Regardless of who did what and when ELON MUSK'S SLUR WAS AND IS UNACCEPTABLE.
Elon Musk's slur cannot be excused by your incomplete Goggleing.


Bill
--------------------
"Why not the best?"
Jimmy Carter
 
3DDave said:
I've looked for anything that is independent of the CNN interview that shows he has done anything or has been acknowledged by anyone besides his own statements.
You're not looking too hard. I posted a link from the Thai Public Broadcast Service from 3 days after they went missing which acknowledges and credits him. It's pretty clear he was in early on this.

 
I know that Vernon Unsworth was there early on, and I know he talked to the press. I am concerned when the facts about him shifted from being a nearby caver that was wrong about where to find the children and being wrong about shutting off the water flow into the cave to being a career rescue diving life risking hero primarily responsible for guiding the entire rescue operation and getting the Thai government to act to save the stranded team.

It seems the shift was necessary to bury his initial attack on Musk and prepare a defense against Musk's comment.

Even here it is suspicious - "Mr Chaiyaporn Siripornpaibul, a caving expert of the Mineral Resources Department, admitted on Tuesday that the department had very limited information about the Tham Luang-Khun Nam Nang Non only about one kilometer into the cave from its entrance," which is weird because there is a survey that was done by another team in 1986 and 1987 and published in final form in 2010.

I posted a link to it: If they had limited information, it wasn't necessary for Unsworth to be involved to find it.

The Sun coverage of the last few days is not independent of the CNN interview because they got their information from exactly the same source - Vernon Unsworth's mouth, after the CNN interview, and in reaction to Musk's Tweet about the CNN interview.

"UNSUNG HERO Who is Vernon Unsworth? Thai cave rescue diver ... The Brit caver co-led the operation to save the schoolboys from Tham Luang cave"

He's not listed by anyone as a diver, not photographed in diving gear, not acknowledged by any other divers, so how did he rescue anyone? And what did he do that was heroic - find a map? Co-led the rescue effort with who? I've seen no defense of Unsworth by anyone on the rescue team and that leaves me suspicious of the press descriptions of Unsworth's involvement.

I don't care one way or the other about their particular dispute. They both behaved badly and I think Unsworth essentially calling Musk a child-killer for being unconcerned about saving them in order to generate PR is on the same or more egregious level as Musk's response. Weren't the claims that Musk's ego interfered with the rescue efforts or that the sub could get wedged and doom them all? Seems like calling Musk and his team a bunch of cold-blooded egomaniac child-killers to me.
 
waross said:
Given that a pump failed and the last diver made it out against fast rising water is a strong indication that the decision to continue with a plan that was working rather than take time out to test a new method was the correct action.

Perhaps a small point, given all of the hubbub, but... I hear/read statements like this often, and I take issue with it. It was a lucky one, it was one that worked out in the end... but that doesn't necessarily make it the right one. Had another option worked, then it would have been called the correct action.

Dan - Owner
Footwell%20Animation%20Tiny.gif
 
Possibly the best response here is to dedicate an old song to you.
Simon and Garfunckles
The Sound of Silence.

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
Had the sub gotten itself jammed in an already tight passage, that would have been the WRONG decision. I think that had they more time, Musk's solution MIGHT have been a good choice, but if it didn't work out, the boys would have been doomed.

In the end, the conventional approach had the fewest unk-unks, and that's what made it the right decision.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
3DDave said:
I know that Vernon Unsworth was there early on, and I know he talked to the press. I am concerned when the facts about him shifted from being a nearby caver that was wrong about where to find the children and being wrong about shutting off the water flow into the cave to being a career rescue diving life risking hero primarily responsible for guiding the entire rescue operation and getting the Thai government to act to save the stranded team.

It seems the shift was necessary to bury his initial attack on Musk and prepare a defense against Musk's comment.

...

I don't care one way or the other about their particular dispute. They both behaved badly and I think Unsworth essentially calling Musk a child-killer for being unconcerned about saving them in order to generate PR is on the same or more egregious level as Musk's response. Weren't the claims that Musk's ego interfered with the rescue efforts or that the sub could get wedged and doom them all? Seems like calling Musk and his team a bunch of cold-blooded egomaniac child-killers to me.

Straying into straw-man territory here, 3D... I haven't seen anything about Unsworth "being a career rescue diving life risking hero primarily responsible for guiding the entire rescue operation." That aside, you admit he helped significantly. Not that it matters. Because even if had had just spent 2 weeks outside of the cave entrance tending pumps, Musk's attack was unwarranted.

And it's clear you care one way or the other. Because you have to parse "PR stunt" into "essentially calling Musk a child-killer for being unconcerned about saving them" to justify Musk's leveling of a horrible slur against that person.

It's also clear, that concern for the children or not, Musk saw this as and was making the most of it as an opportunity for self-promotion.
 
All this Musk hate doesn't seem to be much to do with engineering. Kinda ironic, since Musk is criticized for making a personal attack, but it's ok when Musk is the subject?

Anyway, what goes on twitter is best left on twitter.
 
I disagree that Musk's personality can be cleanly separated from his engineering. His imprimatur is clearly on every product his company makes, not unlike other companies of the past, like Microsoft (in the past), Cray Research, or Wang Computing that were heavily driven and influenced by their founders. His approach to his Tesla's autonomous driving leaves me to question whether his submarine idea wouldn't have had issues in the field. Testing the surrogate sub would have chewed up precious time and still not have guaranteed success, and given the desperate time deadlines imposed by further rains left little choice than to discard his approach for something that essentially was already proven, since the divers could get in and out with all the known difficulties.

Had his sub been tested in that specific cave under those specific conditions, or even tested at all, it, and this, would have been a different story. Clearly, Tesla and SpaceX are trailblazers in their respective industries, but trailblazing entails discovering unk-unks, which is something you don't want to be doing in an emergency. Tesla has had problems even with known unknowns, such a white trucks and traffic lane deviations.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
The investigation into the SpaceX rocket explosion wasn't very kind towards them either. They had issues that were known to be issues and at least some they had been warned about.
 
I have to agree with IRS... I think he's correct on Musk... Musk would have been so much further ahead if he had offered to fund the operation. He did a kazillion dollars worth of harm. I don't know how big a kazillion is, but, I know it has a flock of zeros... and, he really flocked up.

Dik
 
1st Person;
"I just heard that there was a tidal wave and 3 Brazillions died."
2nd person;
"That's terrible. How many zeros in a brazillion?"
Answer.
Even more than a kazillion.

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
The Thai government already funded the operation, so any such offer would be met with rightful derision for supposing Thailand is so poor it cannot afford to rescue its own people.
 
The beginning of another chapter,

"The young soccer teammates and their coach who were rescued after being trapped in a cave in northern Thailand were ordained Wednesday at a Buddhist temple, a merit-making activity to show thanks for their rescue.

The 11 boys, ages 11 to 16, became Buddhist novices in a religious ceremony, while their 25-year-old coach was ordained as a monk. One boy did not participate because he isn't Buddhist."
 
One of the bests doco's on the rescue. Australian ABC - Four Corners.


It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)
 
Lawsuit filed:

Seems Musk doubled down on his horrid accusations (two weeks ago to BuzzFeed News):
“I suggest that you call people you know in Thailand, find out what’s actually going on and stop defending child rapists, you f***ing a*****e. He’s an old, single white guy from England who’s been traveling or living in Thailand for 30 to 40 years, mostly Pattaya Beach, until moving to Chiang Rai for a child bride who was about 12 years old at the time. There’s only one reason people go to Pattaya Beach. It isn’t where you’d go for caves, but it is where you’d go for something else. Chiang Rai is renowned for child sex-trafficking. He may claim to know how to cave dive, but he wasn’t on the cave dive rescue team and most of the actual dive team refused to hang out with him. I wonder why . . . As for this alleged threat of a lawsuit, which magically appeared when I raised the issue (nothing was sent or raised beforehand), I f***ing hope he sues me.”

And for those of you looking for anything independent of the CNN interview that shows Unsworth had done anything or has been acknowledged by anyone besides his own statements... from the BuzzFeed srticle:
“He may claim to know how to cave dive, but he wasn’t on the cave dive rescue team and most of the actual dive team refused to hang out with him,” Musk wrote in one email. In another email in which Musk wrote “on background” — BuzzFeed News again did not agree to these terms — the Tesla CEO said, “Never saw Unsworth at any point. Was told he was banned from the site.”

A British diver on the rescue mission who had previously been in contact with Musk, Rick Stanton, denied those claims.

“I've no idea what gave you those concerns about Vern,” Stanton wrote over Facebook Messenger. “They are completely unfounded. He was never kicked off site by anyone and worked continuously on the rescue for the full duration. He was pivotal to the entire operation.”

Two Australian specialists who were brought in by the Thai government to aid the Thai cave rescue operation, Richard Harris and Craig Challen, also rejected Musk’s allegation.

“Vern seemed like an excellent guy and absolutely vital to the mission,” said Harris, who, with Challen, helped in the sedation of the Thai boys before they were brought out of the cave by the British divers. “You must be confusing him with someone else.”

“He was pivotal with his knowledge of the cave. [The] rescue wouldn’t have happened without him recommending the Brits were called,” Harris said.
 
Seems like the divers are being very diplomatic, given that they and many other participants were specifically given awards and Unsworth was given no official sign of appreciation. Unsworth is certainly not publicity adverse, so I'm sure he didn't swear anyone to secrecy. I'm looking forward to Musk losing the suit and Unsworth being awarded a dollar, as he richly deserves for firing the first shot in this war of stupidity.
 
"firing the first shot"

Seems like a matter of perspective. Seems to me if Musk hadn't attempted a "great white hope" move in the beginning by stepping in an building a something that had dubious benefits, the later exchanges wouldn't have happened. Oh, was I referring to "AutoPilot" or the submarine...?

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
Please, don't think that Musk designed this. I expect at least a dozen engineers worked the problem, so please cast aspersions on all of them for thinking they could help. Call them murderers for taking a shot at a design the lead diver on the rescue suggested they continue to work out.
 
"so please cast aspersions on all of them for thinking they could help. "

They were employees of Musk's companies gathered and funded by Musk, weren't they? I've nothing against the engineers; they worked with what they had, and they were directed by Musk.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
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