Alvin Submersible Retired After 40 Years Work

An anonymous reader writes "The legendary deep-sea manned submersible Alvin is retiring after 40 years of scientific work. Alvin has taken 12,000 people on over 4,000 dives, helping to confirm plate tectonics and continental drift. It discovered hydrothermal vents, salvaged a hydrogen bomb from the Mediterranean Sea and explored the Titanic. Alvin will be replaced by a larger vehicle that will come into service in 2008."

Comments

Keep Both

[darkmeridian]

Is there any reason not to keep Alvin going along with its replacement? I'm sure some country or foundation is willing to run it. There's nothing top-secret in it, is there, considering that it is forty years old.

It is useful for a lot of research. Even though it is not as good as a new one, why not keep in it action?

Re:Keep Both

[TAGmclaren]

It is useful for a lot of research. Even though it is not as good as a new one, why not keep in it action?

At a guess, after 40 years of the pressure it's been subject to it may be cheaper to replace that guarantee structural integrity.

Anyway, I hope "retire" is accurate and not a euphemism for scrap (which unfortunately happens sometimes). It deserves a pastures in a museum somewhere, at the very least.

Re:Keep Both

[axioein]

To me, this is old news. As I worki at WHOI, we have been tossing around ideas for a new Alvin for a long time.

To correct a few other posts, on fatigue: the factor of saftey of Alvin is incredibly high. Meaning the operating depth is incredibly low for the hull. You can check the ASME boiler code. No one actually knows the crush depth of the sphere. They re-wrote the book when they built the spere. They built three spheres from the get go. One to be tested to failure. Instead of failing it caused the pressure chamber to explode. The rapid decompression also did nothing to the hull.

Related to that there are only two original pieces of Alving left: the name and the robotic arm. The rest has been replaced. Many times.

As many others have said cost is another factor. Sea Cliff, Alvin's sister sub, is housed at WHOI. I thought, wouldn't it be great to get two subs going? Looking over the systems it would take a lot to overhaul the entire system. The cost of operating Alvin is also climbing each year, as key compenents are harder to find. Our budget is also quite limited. Operating two submarines would be impossible. We would need a second support ship to be able to handle the second submarine, and no one would be willing to convert WHOI's two other Deep Sea ships to handling a submarine. As they do valuble research on their own using other tools. To convert Atlantis to handling a second sub, would be near impossible with out overhauling the entire ship. Lab space on ships is quite precious and I doubt any one would want to give it up. As the two subs will be different an many if not all aspects, they would not beable to share parts, doubling the inventory on the ship taking away even more room. Also Alvin's view ports aren't set up the best. Since the sub was experimental they didn't know what would work out best. It has about 180 degrees of view, but only one person can see any one third of that. Meaning the scientist can't see what the pilot sees with out displacing him. As some one else said: scrab the obsolete. It costs somwhere in the neighbor hood of one to two million dollars to run the sub each year. We deffinately don't have the resources to deal with twice that. We are stretched to the limits already. WHOI gets minimal amount of Goverment funds already. The cost that a scientist will pay for a trip in the submarine doesn't actually cover the entire dive.

If you want to read more on Alvin I suggest Water Baby. An excellent tale of a submarine and it's life.
http://www.amazon.com/exec/obidos/tg/detail /-/0195 061918/qid=1098555276/sr=1-1/ref=sr_1_1/002-829162 3-6347207?v=glance&s=books

DSV-2

[Pan T. Hose]

For those who don't know, DSV Alvin is better known as DSV-2 in most of serious historical documents.

Parts

[nounderscores]

I'd hate to think of how much it would cost to replace some of the heavily fatigued major components that have been compressed and decompressed so many times.

And who is willing to make another alvin hull?

Might be better to build 2 of the next generation once it is proven, or build 20 of the original alvins from scratch, than to try and extend the service life of a sub that's given more than its due.

Re:Parts

[DerekLyons]

I'd hate to think of how much it would cost to replace some of the heavily fatigued major components that have been compressed and decompressed so many times.

Such replacement has been done incrementally over many years. No part currently installed in Alvin is original, or (IIRC) any older than about 10-15 years.

And who is willing to make another alvin hull?

Any number of the firms around the globe who are currently involved in building deep submersibles. Alvin was the first, and is far from unique. (In fact the Navy has two Alvin type submersibles (built from spare hulls) in mothballs in San Diego (Sea Cliff and Turtle).)

Keeping both is a waste of money

[October_30th]

It is useful for a lot of research.

In the life of every scientific instrument comes the time when its capabilities are so much overshadowed by the more contemporary technology and its maintenance is such a drain on the funds that it simply must be retired. Sure you can do research with it, but it's low grade. They simply are not useful for good research anymore and maintaining them will take away funds from more important, new fields.

Personally, as a scientist, I don't much care what happens to what is essentially scrap metal at that point. In fact, I personally dismantled the equipment I did my PhD Thesis on in order to build another, better one. No tears shed there.

Re:I remember Alvin

[DerekLyons]

Alvin was an envelope-pusher from day one. The two halves of the titanium sphere that was the crew compartment were held together by one of the hardest titanium welding jobs ever done.

That's both true and false. Alvin's first two hulls were steel, not titanium. While she was unique in her role, she didn't particularly press the envelope with them.

The titanium hull was not installed until she had been in service many years.

Alvin did have an emergency ascent capability. Explosive bolts would shear the sphere clear of the boat-shaped outer chassis which contained the ballast, batteries and engines, allowing the sphere, a giant bubble, to race to the surface.

Incorrect.

Alvin has not one but *three* emergency ascent capabilities.

• Electromagnetic release of ballast plates. (Also used to initate a normal ascent.)
• Electromagnetic release of the battery tubs.
• *Manual* seperation of the sphere and forward chassis from the remainder of the submarine. (No one is certain if this will work.)

Lastly, Alvin also has the ability to shed her arms and the experiment rack/ROV garage. This is used both if they get entangled or if they need to shed weight.

USN DSVs

[Anonymous Coward]

"DSV-0" Trieste - the bathyscathe that reached Challenger Deep, retired 1966, also called X1
DSV-1 Trieste II - an updated bathyscathe design, retired 1984, also called X2
DSV-2 Alvin - a deep diving sub, reaching only half as deep as the two Triestes
DSV-3 Turtle - Alvin's identical sibling, retired 1998, USN
DSV-4 Sea Cliff - another Alvin class DSV sub, retired 1998, USN
DSV-5 Nemo - another Alvin class DSV sub, retired 1998, USN