Titanic tourist sub goes missing sparking search

[Dan]

interesting story told by Dr. Michael Guillen, Journalist who visited Titanic Wreck with Russian Sub, getting stuck on the Titanic propeller and managed to get out of the trap at 3800m depth.

 

[tomfcrist]

NPR says the Canadian Coast Guard is dropping sonobuoys.

I worked on sonobuoys for the navy.

You can hear shrimp doing the nasty in 25,000 feet of water.

You would hear a wrench against the hull.

The stuff I learned about bouys at AUTEC was certainly an eye opener

 

[Wookie]

The stuff I learned about bouys at AUTEC was certainly an eye opener

The AUTEC buoys have a different task than a sonobuoy, but yes, very impressive.

 

[telemonster]

In the one document it made it sound like the human compartment is a solid composite thing with no holes or ports through it except for the viewing port. They screw it on before it goes down, and sounds like there is no way for occupants to open the hatch nor one of those valves for ambient air like the full face masks have.

Apparently a lot of systems were pretty redundant on the thing. Power didn't matter. There is a reporter talking to some other ?reporter? that went on a prior mission and he was describing how a lot of the systems work. David Pogue. One of the interviews he did talks about the redundancy. Air was scrubber, some kind of fly tape type stuff, then tanks that are under the floor. Boyancy had 7 redundant systems including some that are supposed to "auto fire.." Apparently Cameron had something similar where the bolts are made of candy and give way after X amount of hours in the water.

This isn't the exact video but this Pogue guy seems to have the best talking descriptions as he went on one of the journeys.

 

[tomfcrist]

The AUTEC buoys have a different task than a sonobuoy, but yes, very impressive.

We drop sonobouys like candy down there. Good training.

 

[Dan G]

From the NYT:
Leaders in the submersible craft industry were so worried about what they called the “experimental” approach of OceanGate, the company whose craft has gone missing, that they wrote a letter in 2018 warning of possible “catastrophic” problems with the submersible’s development and its planned mission to tour the Titanic wreckage.

The letter, obtained by The New York Times, was sent to OceanGate’s chief executive, Stockton Rush, by the Manned Underwater Vehicles committee of the Marine Technology Society, a 60-year-old trade group that aims to promote ocean technology and educate the public about it.

 

[Wookie]

[ETA: Assuming they aren't already surfaced and unlocated ...] It is over two miles below the surface, the sound falls off proportionally to the square of the distance, and the ocean is a pretty noisy place. If they dropped deep subsurface hydrophones, maybe ...

Hmmmm.
From physics it will be remembered that when gas is the transmitting medium, the denser the gas, the slower the speed of sound, and yet the speed of sound in water is about four times greater than that in air. Although this seems contradictory, it is not, because there is another more important factor that influences the speed of sound. In truth, the speed of sound is determined primarily by the elasticity of the medium and only secondarily by the density.

From PRINCIPLES OF UNDERWATER SOUND Chapter 8

 

[berndo]

Boyancy had 7 redundant systems including some that are supposed to "auto fire.."

One is supposed to blow up an air bag. How do you blow up an air bad at 4000m? Where would they have stored all that gas and at what pressure?
Other than dropping weight what possible system could there be to make a sub like this ascend in an emergency, I wonder.

 

[grf88]

One is supposed to blow up an air bag. How do you blow up an air bad at 4000m? Where would they have stored all that gas and at what pressure?
Other than dropping weight what possible system could there be to make a sub like this ascend in an emergency, I wonder.

Maybe pumping out water ballast.

 

[telemonster]

One is supposed to blow up an air bag. How do you blow up an air bad at 4000m? Where would they have stored all that gas and at what pressure?
Other than dropping weight what possible system could there be to make a sub like this ascend in an emergency, I wonder.

Make an air tank out of the composites the sub is made out of, pump it up to 10k psi?