DCS and the Sci-Fi TV Show "Silo"

[justinthedeeps]

Compare/contrast to the awesomely almost good (new) Hawaii 5.0 episode, where they toy with oxygen percentages at depth and do world record 100 metre freedives / emergency ascents!

Those Above are Descending

Those Above are Descending (Ke iho mai nei ko luna) is the 13th episode of Season 9 in the remake version of Hawaii Five-0. Adam, Junior and Tani travel to the bottom of the Pacific Ocean when a murder takes place in a remote underwater lab, and the killer may still be on board. Danny was...

hawaiifiveo.fandom.com

 

[Dan G]

I like the books a lot, too, and enjoy the show just as much. There's some pretty great acting by Tim Robbins and I like post-apocalyptic stories. David Oyelowo is great in season 1 Steve Zahn is excellent in season 2.

Each level in the silo is about 40 feet in depth, so the dive is deeper than 150' because that would mean only about 4 levels are flooded between where they begin the dive and the mechanical level where the water pump needs to be reconnected. More than four levels above mechanical have flooded.

Would we truly consider the air inside the silo 1 ATA? The very top level is at the surface. If the physiology of the inhabitants has changed over the many generations of people living in the silo, would we recalibrate 1 ATA to this particular environment or recalibrate where prolonged O2 exposure can cause seizures?

Also, forgetting that a small power washer pump would really struggle to get air through 300' of hose submerged underwater, does the fact that the air is pumped down to the diver rather than being compressed change her nitrogen loading?

Book readers already know why this diver might be able to survive this particular dive, it's profile, and the rapid ascent.

 

[inquis]

does the fact that the air is pumped down to the diver rather than being compressed change her nitrogen loading?

It must be compressed to at least that of the ambient pressure at depth (~150 psi at 300 ft). She would not be able to take a breath otherwise.

 

[lowwall]

Quoting myself from a different thread about scientific howlers in fiction:

...the BS diving stuff in the science fiction series Wool (aka Silo) did cause me to abandon the books. It was especially annoying because the author (who responds in the Reddit thread linked below) was a former commercial diver and knew what he was writing was crap, but needed a gimmick and decided people wouldn't care.


Here's the response from the author:

Author was a commercial scuba diver doing salvage work before Reddit even existed. Has done wreck dives of depths over '150. Spent most of his life living on boats with dive tanks and compressors plumbing the depths of the oceans all around the world.

Author was a physics major and math minor who managed Boyle's Law just fine but struggled in Linear Algebra.

Author also learned a long time ago that most people just want an exciting story and not to pander to pedants who are a vast minority of the reading population and don't really move any needles.

 

[Dan G]

I agree the science behind the dive is not great and can take someone out of the story. I don't have a problem with that. That being said, I just don't care enough for it to have ruined the books or the show. In the books, the dive is shallower for sure. Since the Silo trilogy takes place in the not so distant future on Earth, the parameters for what is "believable" are different than Star Wars or Star Trek. For example, in the Star Trek and Star Wars worlds we accept that traveling faster than the speed of light is possible.

It must be compressed to at least that of the ambient pressure at depth (~150 psi at 300 ft). She would not be able to take a breath otherwise.

Absolutely. I guess my wondering is if the gas is compressed less when pumped from 1 ATA compared to when the air is self contained and breathed through an apparatus? Would this difference impact nitrogen loading calculations? Also, what impact does the depth of the air originating from halfway down the silo have on all of this?

 

[inquis]

Would this difference impact nitrogen loading calculations?

No. Once in the lungs, that gas is at ambient pressure. Whether it was highly compressed in a tank then reduced in pressure by an apparatus (i.e., a scuba regulator) or fed through a hose after bring compressed just enough to be breathable doesn't matter for tissue loading.

 

[inquis]

Also, what impact does the depth of the air originating from halfway down the silo have on all of this?

Very little, as that's just the starting pressure. The final pressure still has to be the same.

 

[lowwall]

Quoting myself from a different thread about scientific howlers in fiction:

...the BS diving stuff in the science fiction series Wool (aka Silo) did cause me to abandon the books. It was especially annoying because the author (who responds in the Reddit thread linked below) was a former commercial diver and knew what he was writing was crap, but needed a gimmick and decided people wouldn't care.


Here's the response from the author:

Author was a commercial scuba diver doing salvage work before Reddit even existed. Has done wreck dives of depths over '150. Spent most of his life living on boats with dive tanks and compressors plumbing the depths of the oceans all around the world.

Author was a physics major and math minor who managed Boyle's Law just fine but struggled in Linear Algebra.

Author also learned a long time ago that most people just want an exciting story and not to pander to pedants who are a vast minority of the reading population and don't really move any needles.

 

[VikingDives]

Everyone (save @-JD- ) is forgetting that if the tower is below sea level, the negative altitude must be considered. If she's going to 150' the adjusted depth would be something like 136' but I'll leave it to someone else to do that math.

 

[inquis]

if the tower is below sea level, the negative altitude must be considered.

It's actually the ambient pressure at the water's surface that's important. It's still not clear whether the water is open to the outside world or not. If it is, then the silo would have to be pressurized to avoid the water from rising. The equivalent negative altitude in that case would be much, much more than the distance to the outside surface.

To your point, however, in either case NDL would indeed be increased over that of a dive at 1.0 atm surface pressure.