
SpaceX is working on a kid-size submarine to extract those boys in Thailand - allenleein
https://techcrunch.com/2018/07/07/elon-musk-says-spacex-is-working-on-a-kid-size-submarine-to-extract-those-boys-in-thailand/
======
slimsag
For those confused by this: What they are making is less of a "submarine" in
the mechanized sense, and more of an enclosed, air-tight & weighted chamber
which two divers can tow between them (one diver in front, one behind) with a
kid inside. So about the size of an adult body, hence being able to fit
through the narrow caves.

~~~
everdev
If the passages are narrow, why is an inflatable pod a preferred solution to a
face mask? I'd imagine it would be at risk of puncture.

~~~
sandworm101
There are so many issues with either a pod or a solid tube. The biggest one is
buoyancy. If it is full of air it will need to be weighted, and have air
added/removed to adjust for pressure changes with depth. But imagine if the
kid "turns turtle". Any brief head-down orientation will result in the fabric
collapsing around the kid's head as the air rushes up to his feet. Correcting
this requires forcefully turning the kid around to keep his head up. This is
one (of many) reasons why commercial divers in dry suits use solid helmets. It
isn't an issue for wetsuits. I'd rather slap a full helmet on the kid and tie
him up into a bundle. It won't be pretty but does solve the buoyancy issues.
I'm sure they are also considering drugging the kids to reduce the risk of
panic attacks.

Here is the nasa device, the personal rescue enclosure:

[http://www.astronautix.com/r/rescueball.html](http://www.astronautix.com/r/rescueball.html)

(It wouldn't work. Wrong shape and no buoyancy control.)

~~~
richev
Of the difficulties the pod solution poses, I don't think that neutral
buoyancy us one of them, so long as the pod is rigid (e.g. steel) in
construction.

The best succinct definition for neutral buoyancy I could find was this one,
from Wikipedia:

> ...a condition in which a physical body's average density is equal to the
> density of the fluid in which it is immersed.[0]

This means that once the pod has been weighted to be neutrally buoyant it will
be so at any depth of water, since neither it or water are compressible[1] and
thus their average densities are unchanged by depth.

The challenges of maintaining neutral buoyancy arise when you submerge a
compressible object, such as a scuba diver wearing an inflatable buoyancy
control device (BCD). The water pressure (caused by the weight of the water
above) will squeeze them and their equipment, compressing anything that is air
filled.

To sink from the surface, the diver has to deflate their BCD, and then put
sufficient air in it to achieve neutral buoyancy at their desired depth. If
they swim downwards, the higher water pressure will squeeze them some more,
the air in their BCD will compress some more, and their average density will
increase. They will now be negatively buoyant and will sink.

The deeper they sink, the higher the water pressure will be, the more the air
in their BCD will compress and the more negatively buoyant they will become.
So they'll sink faster and faster. This happened to me once when I was first
learning to scuba dive. It can be scary.

The opposite applies to ascending. This is why good buoyancy control is such
an important (and difficult) thing for scuba divers to learn.[2]

From a buoyancy perspective, a metal pod is more like a camera in an
underwater housing. These are rigid in construction (usually either plastic or
metal) and their buoyancy characteristics don't change with depth.

[0]
[https://en.wikipedia.org/wiki/Neutral_buoyancy](https://en.wikipedia.org/wiki/Neutral_buoyancy)

[1] Not strictly true for water, but true enough for scuba diving depths

[2] [https://www.padi.com/courses/peak-performance-
buoyancy](https://www.padi.com/courses/peak-performance-buoyancy)

~~~
nradov
None of this is relevant because the cave contains a restriction so tight that
a rigid pod wouldn't fit through. The last thing they want is a solid object
wedged into the restriction.

The SpaceX design is apparently flexible to fit through the cave, so some
buoyancy adjustments would be necessary.

~~~
richev
With a flexible pod, you'd partially deflate it to get it through awkward
areas, which would make it negatively buoyant. Once re-inflated to the
previous pressure it would be neutrally buoyant once again.

Re-inflation could be done via the same gas cylinder that's being used to
replenish the air in the pod.

~~~
tlrobinson
But if it's flexible then, like a driver with a BCD, it won't remain neutrally
buoyant at every depth.

------
mjal
Not SpaceX, a partner company. While helping is admirable, if he actually
wanted to help in a more reasonable timeframe/more humble way then there are
better channels he could have used, this all seems like a publicity stunt to
me.

~~~
Walkman
It might not have been his idea at first to help, I found this tweet:
[https://twitter.com/mabzmagz/status/1014251869760249856?s=21](https://twitter.com/mabzmagz/status/1014251869760249856?s=21)

~~~
unityByFreedom
Chiang Rai governor: “i am the one who invited @SpaceX because my friend works
there.”

[https://twitter.com/yayqe/status/1015287476284346368](https://twitter.com/yayqe/status/1015287476284346368)

[https://www.theguardian.com/world/live/2018/jul/06/thailand-...](https://www.theguardian.com/world/live/2018/jul/06/thailand-
cave-rescue-looming-rain-clouds-could-force-quick-rescue-decision-live)

------
Robotbeat
It sounds like the rescue operation has begun. 5 thai navy seals and 13
foreign divers have entered the cave:
[https://twitter.com/gordoneaton/status/1015805529950650373](https://twitter.com/gordoneaton/status/1015805529950650373)

[https://www.theguardian.com/world/live/2018/jul/08/thailand-...](https://www.theguardian.com/world/live/2018/jul/08/thailand-
cave-rescue-operation-divers-trapped-boys-live?CMP=share_btn_tw)

~~~
geomark
Yes. Thai TV is currently reporting that the extraction operation has begun.
The stateless kid (forgot his name), the only English speaker, will be the
first one to make the attempt. They expect/hope he will emerge around 9pm Thai
time this evening, about four hours from now.

~~~
geomark
Thai news reporting that the first two boys are out of the cave. No report yet
of their condition.

Edit 1: News media being kept away so they will be light on details for the
time being.

2: Chiang Rai health dept head says the two are being examined at the field
hospital near the cave.

3: Timely updates in English here
[https://www.bbc.com/news/live/44755093](https://www.bbc.com/news/live/44755093)

~~~
glenneroo
On your BBC link, they got 4 kids out, all in good health. Taking a break for
the night:

> We will be able to continue the rescue operation when we are ready to do so.
> We will be ready soon, because we will need to redo laying out all of the
> air tanks and all systems along the way again. We have used everything [in
> the set up] that we had today. The set up team will do their work again once
> they are ready. It'll be difficult to tell exactly when the next
> [evacuation] will start. But I guess it will be ready in the next 10-20
> hours.''

8 kids and the coach are still inside. Looks like they may not need any
outside help after all.

------
guard0g
The pods already on their way via SpaceX [http://www.times-
standard.com/general-news/20180706/wing-inf...](http://www.times-
standard.com/general-news/20180706/wing-inflatables-assisting-with-thai-
soccer-team-rescue)

~~~
wallflower
Wing Inflatables is a partner for SpaceX. This is pretty smart as they had
expertise in flotation devices. The general assumption that SpaceX was
designing and manufacturing these out of SpaceX spacecraft material was wrong.
In fact, they were probably en route via Elon's private jet around the time he
started tweeting about them.

> 14/ "What is interesting is, if you know #California at all, we are 350
> miles north of #SanFrancisco in a little town, #Arcata. That is a little
> #riverrafting town. We manufacture inflatable recovery parts for #SpaceX".

> 15/ "So we have a relationship. When Elon had an idea he asked our
> engineering team to get a hold of us. It was wonderful to see it all come
> through", says Branagh, Wing Inflatables' president and CEO.

[https://twitter.com/WendyDent/status/1015795955621191680](https://twitter.com/WendyDent/status/1015795955621191680)

[http://www.wing.com/](http://www.wing.com/)

~~~
arkades
It wasn’t a general assumption: he said as much in a tweet.

“Got more great feedback from Thailand. Primary path is basically a tiny, kid-
size submarine using the liquid oxygen transfer tube of Falcon rocket as hull.
Light enough to be carried by 2 divers, small enough to get through narrow
gaps. Extremely robust.

— Elon Musk (@elonmusk) July 7, 2018”

~~~
wallflower
Hmm, it appears that SpaceX designed their own escape pod, separate from the
Wing Inflatables which were flown to Thailand. While it is clear they didn't
finish it in time for the very time sensitive Thai cave rescue operation, they
are testing it out in a pool.

Video of it being tested:
[https://twitter.com/elonmusk/status/1016063173139427329](https://twitter.com/elonmusk/status/1016063173139427329)

------
jpindar
I'm hearing news that that the rescue is about to begin, they aren't going to
wait for any new equipment.

"Rescue crews: the 12 boys + coach each have a dive mask connecting with an
air line to their escort/diver. The diver has the oxygen tank/regulator. So,
the boys are not SCUBAing, per se. Also, each boy will have physical contact
with their rescuer throughout."

[https://twitter.com/DavidShuster/status/1015789259649937409](https://twitter.com/DavidShuster/status/1015789259649937409)

~~~
XorNot
11 hours minimum per boy for the trip though. Hopefully it all works but I'd
hope the backup plan preparations are continuing.

~~~
TheSpiceIsLife
Wowsers! I haven't been following this.

Does anyone have any info on what the route is out of the cave? That's a
hectic journey.

------
sandworm101
What is Musk thinking? First the bouncy castle tube and now a solid-walled
submarine? He really has no appreciation for the cave environment.

Tight spots in caves aren't tubes. They are irregular twisty-turning CAVES.
Some squeezes (the term of art for the narrow bits where you have to remove
gear) are so tight that you cannot take a full breath. Any solid object more
than a couple feet long will be stuck very quickly. Now imagine that in the
dark, not seeing more than a few _inches_ in front of your face. Then add a
swift current constantly trying to separate you from your air supply. When a
hardened cave diver calls something "gnarly" take it to mean a claustrophobic
nightmare that would send 99% of us into a lethal panic attack.

Worse yet, imagine this sub becoming wedged in a squeeze. Setting aside the
terrified kid dying inside, the only way to or from the twelve others is now
blocked.

I'm a diver but no expert on caves. I've been in dry caves and have dove a
couple lava tubes, but I would never tell proper cave divers how to do their
thing. If I were the King I would airlift every possible drilling rig in Asia.
I'd turn that mountain into a wiffle ball in the hopes that one breaks
through, or at least add more places for pumps.

~~~
rurban
At least the pumps did work. Before I only saw two small 10cm waterhoses going
out. Yesterday I saw a double size 30cm hose pumping water out in full speed.
These 30cm made the difference I believe.

~~~
iamgopal
Yes pumping is the proper solution as long as they have drain point. Humans
have mastered pumping.

------
foobarbazetc
The actual operation has no mention of this stuff at all:

[https://www.theguardian.com/world/live/2018/jul/08/thailand-...](https://www.theguardian.com/world/live/2018/jul/08/thailand-
cave-rescue-operation-divers-trapped-boys-live)

And the pre-planned operation is under way due to lower than expected rainfall
making most of the journey walkable.

So what’s what? Why are we talking about Elon or SpaceX at all?

~~~
8bitsrule
Because 1. It's great idea? and 2. May be a lifesaver in many other use cases?
and 3. Is a good example of tech used to help, not just take? and 4. Beats
watching TV?

------
ericcumbee
Sounds kind of like what NASA came up with for moving astronauts from a
damaged space shuttle to a rescue shuttle.
[https://en.m.wikipedia.org/wiki/Personal_Rescue_Enclosure](https://en.m.wikipedia.org/wiki/Personal_Rescue_Enclosure)

~~~
orbital-decay
Along with concepts like PARACONE or Langley Landers, it was one of the
crazier space technologies though.

------
craftyguy
It's somewhat interesting how much attention these kids have received,
meanwhile how many kids have died worldwide from hunger, disease, and warfare
since June 23rd? Probably a bit more than 12. I guess that's not as exciting
to read about though.

~~~
mdorazio
I made a lot of family members really mad yesterday by saying exactly this.
Then I looked up some stats. The numbers are a few years out of date, but
UNICEF estimates that 29,000 children under the age of five die of preventable
causes _every day_ [1]. And those kids didn't do anything wrong to get
themselves a death sentence. Now ask yourself how many of those kids could
have been saved with the amount of money, manpower, and attention being
devoted to the Thai soccer team.

Stuff like this gets pretty sad if you think about it in utilitarian terms.

[1]
[https://www.unicef.org/mdg/childmortality.html](https://www.unicef.org/mdg/childmortality.html)

~~~
triviatise
the same goes for any social problem you help solve.

People are quite upset about kids getting separated from parents at the
border. Yet offer no help for the thousands of children that die every day.

Every person decides what cause is important to them. The hypocrisy is when
people who favor one cause judge those who arent interested in that cause.

~~~
curiousgal
I am not fishing for drama but I want to speak my mind. On that note, the most
blatant form of hypocrisy in my opinion is pro-"life" supporters whose main
argument is "think of the children" yet they also ignore the thousands of
children that die every day.

~~~
iamgopal
What do you think of masturbation ?

~~~
dang
Please don't do this here.

------
grosjona
It seems crazy, I can imagine the horror if the pod gets stuck between rocks
while going through a narrow tunnel.

The simplest solution is to give the children swimming and scuba diving
lessons from inside the cave and then once a safe route has been established,
the children can get to the exit one by one (accompanied by a professional
diver) by swimming along a rope which leads to the exit.

------
falcolas
IIRC they've been talking about the potential of "packaging" up the
individuals since they first found them. Packaging being giving them an air
tank, face mask, and making them neutrally buoyant them so the experienced
divers can push and pull them along the tunnels.

This seems like the implementation of that plan?

~~~
coatmatter
The repeated stories so far have suggested that there's a passage that's too
narrow for both a tank and person to fit through at the same time.

~~~
falcolas
So long as the professional divers have full control over the "package", it
shouldn't be a deal breaking issue. Detach the tank, move them through
separately, just as the divers themselves do.

It's certainly not safe, as the loss of the recent diver has shown.

~~~
xxxdarrenxxx
Little is known about why he died. I see many people go full tryhard when a
child is in danger, doing dumb stuff.

I can see a scenario where he wanted to rush it, potentially cuttin corners,
because of doom rainfall scenarios. This makes his death more a psych problem
than a dive problem.

Another is age/shape. I used to be a fine skater, did a trick I could do in my
sleep at 14 at 30 and fell hard. These kind of coordinations need to be
maintained and he was explicitly retired.

------
guard0g
Pods are onsite and rescue operation has started according to news conference
#thailandcaverescue

------
pbw
Whether this has a chance of working depends on the exact diameter of the
narrow portions of the submerged route. My impression is that they were _very_
narrow, perhaps too small for a rigid container containing a human?

~~~
Robotbeat
Indeed. The "submarine" is more like a duffel bag with air tanks and weights.
It isn't rigid.

I think it might work. It helps that they are very young and small and
athletic build (and now, unfortunately, really skinny due to not eating much
food for the last couple weeks).

~~~
walrus01
I am thinking of the obviously watertight and airtight flexible, yet very
tough material used for collapsible diesel fuel bladders... Fitted out with an
air tank supply and ballast weight mounting positions?

[https://www.google.com/search?q=diesel+fuel+bladder&num=100&...](https://www.google.com/search?q=diesel+fuel+bladder&num=100&client=ubuntu&hs=KOh&channel=fs&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjy4OH3to7cAhWOITQIHTChBycQ_AUICygC&biw=1473&bih=951#imgrc=_)

~~~
maxerickson
According to the Time article someone linked they are made of the polyurethane
used to make inflatable river rafts and the like.

------
spondyl
Context from the article on who "those boys" are:

12 young soccer players and their coach who’ve been trapped in a cave in
Thailand since entering it June 23rd, after which they became trapped by
rising floodwaters.

------
jv22222
Original Tweet:

[https://twitter.com/elonmusk/status/1015657378140704768](https://twitter.com/elonmusk/status/1015657378140704768)

------
coding123
unless this is ready now it's not being used, they are apparently going to
mask and dive with the children at this point

------
hyperpallium
Also, an inflated "bouncy castle" tunnel.
[http://abc.net.au/news/2018-07-06/elon-musk-sends-spacex-
to-...](http://abc.net.au/news/2018-07-06/elon-musk-sends-spacex-to-help-
rescue-thai-soccer-team/9950934)

~~~
garmaine
That was a tweet and a pretty ridiculous one. These sorts of caves are
famously full of razor sharp rock that would puncture such flimsy inflated
underwater structures.

~~~
chris_mc
I don't like Elon much (I think he's an ass to his employees), but he still
sent engineers for free to Thailand and is donating materials that are
probably not very cheap (rocket parts for the mini-sub thing). At least he's
trying to help!

~~~
coatmatter
He's doing it for free? Where did you read that?

~~~
TomMarius
He is of course getting a lot of attention and it might be one of the reasons
he is doing it, but he is definitely helping and he isn't receiving money, is
he? I think attention is fair price to pay to Elon for his help.

------
westmeal
Hell if they make it...

I'm praying for them.

------
sschueller
The kids would need to be in the bag for 6 hours. I don't see how that is any
better than them going directly.

Maybe Musk should send a giant pump to get that water out. Don't they have
large pumps at space X to fill those rockets?

~~~
crooked-v
> I don't see how that is any better than them going directly.

It means they don't need to keep themselves oriented in an underwater 3D maze
while operating unfamiliar breathing equipment.

~~~
YZF
I'd imagine two or even four divers taking each kid in between them. I assume
there's a line, so no one is navigating and the route is fully supplied with
any additional air needed. People go on intro dives all the time where an
instructor does everything. Obviously the element of the long and narrow
passages makes things a lot more difficult but it's doable. You just take your
time. This completely unknown new technology seems riskier to me... Full face
dive masks take most of the "tricky" don't breath in through the nose out of
the equation. I'm a sport diver.

That said, there's always some people who "lose it" during a dive course or
even newly certified divers. Though I've yet to hear of anyone who decides to
stop breathing air and opt for water, usually they bolt to the top, which
isn't an option here. That risk can be mitigated by doing "pool" dives right
where the kid are and perhaps short stays in the adjacent cave areas. Maybe
some relaxing music can be played as well... Another possibility is adding
some "rest stop" by creating air pockets along the way.

~~~
curiousgal
Things you are ignoring:

1- We're talking about kids who haven't dove before and probably don't even
know how to swim

2- The visibility is 0. Some would be uncomfortable walking through tight dark
spaces, let alone having to dive through them.

3- They're kids.

~~~
sannee
> probably don't even know how to swim

I find it surprising that clearly sport-oriented children from a fairly
popular tourist beach destination don't know how to swim.

~~~
curiousgal
If you are poor living away from the beach, it's perfectly natural that you
spend your entire childhood without even seeing the beach let alone learning
how to swim. Thailand is not an island.

~~~
sannee
I live in a landlocked country and nearly everyone I know can swim. People
usually swim in public pools, lakes or ponds. Swimming is also very often part
of the PE middle school curriculum here.

~~~
blackoil
Good of your country. Many cities in SE Asia have none of three. If you are in
upper middle class, you can afford private swimming pool membership. Less then
.1% schools have swimming pool. Rivers are polluted enough and have no
infrastructure in place for swimmers.

------
Animats
If it fits, it might work.

------
MarketingJason
I'd imagine you'd have to sedate the passenger? That would be far too scary
and long a trip to risk them panicking when there is nothing you can do.

~~~
ars
I'm not sure it would be safe to sedate someone and then leave them in an
inaccessible location for a few hours.

Better to take a chance on ordering the boys to lie there and DON'T MOVE!

Could also help to make them stay awake for a long time, then transport them -
they'd likely fall asleep in the dark quiet.

~~~
Someone
I doubt they would fall asleep, as the experience of being wrapped up likely
would still produce plenty of adrenaline.

And would it be quiet? I would expect sounds of air bubbles, breathing
apparatus, scratching along rock in the tightest passages, etc. Nothing high-
volume, but it would certainly be audible.

------
lossolo
They already evacuated 6 boys without submarine.

------
SubiculumCode
I cannot fathom this as a publicity stunt. Instead it strikes me as kick-ass
can-do attitude of the best kind.

~~~
maxxxxx
I hope it's not an arrogant really-don't-understand-the-problem attitude. Tech
people are very prone to think they know better.

~~~
SubiculumCode
That is possible; but then the guy on site can just say thanks but no thanks.

------
jacksmith21006
They have started to take the boys out and so not in time. But also it looks
like the opening is tiny in places.

There is zero chance I would crawl through such a tiny hole even without the
water. I would freak.

------
evanm
I'm........skeptical about all of this. Kid-sized sub built from rocket parts
in a matter of hours?

~~~
lifeformed
It's mostly just an inflated kevlar bag with some valves.

------
foobaw
It looks like they're going in to rescue the kids based on the current
conditions. I'm guessing this submarine solution could potentially be a back-
up in case something goes wrong. I doubt it's a PR stunt - Elon doesn't care
about PR (remember his April fools tweet).

~~~
jhanschoo
> Elon doesn't care about PR

From recollection, that does not seem true at all. All of Musk's initiatives
have benefited from his intuitive ability for hip and technophilic branding.
See the naming of "Tesla" and "The Boring Company". He also likes to frame his
companies' activities in the context of techno-utopian contributions to civil
society, and this is nothing new. Outside of the obvious main electric-cars
mission of Tesla, they have also built a battery power reservoir in Australia
as well as dabbled in solar panels.

As SpaceX, sending a Tesla into space was great PR.

As the Boring company, they sold overpriced flamethrowers as great PR to the
technophile crowd.

Whenever a safety incident regarding a Tesla car occurs, Tesla issues a heavy-
handed, highly defensive piece spinning their cars to be among the safest,
with a constant undertone of shifting all possible fault elsewhere. The April
fools tweet sends a sort of "haters gonna be haters" message to his Tesla
fans.

So Musk is indeed highly aware of marketing and branding, and this proposal is
highly consistent with Musk's branding and strategy. It has the Musk elements
of proposals that

1) seem prima facie simple 2) seem prima facie feasible 3) solve a
longstanding big or deep problem, that 4) the layman does not think has been
seriously considered before as a solution to the problems it tries to solve,
5) where the problem is currently being addressed by a very different solution
that seems technologically uninteresting or costly.

