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[Susan Humphris] This year is the 50th anniversary of The

Alvin. It's been in service for science since 1964.

It's the only deep diving submersible in the U.S.

[Man] Scientific community decided that they needed some

increased capability.

[Peter Girguis] Was really a re-build of the entire

submarine. It was an opportunity to see how scientists and

engineers could work together to solve problems that would

enable them to do science that couldn't be done before.

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Bow to stern the sub was disassembled, and reassembled,

and the majority of the components on the sub, especially

the major components like the sphere are brand new.

The highest risk part of the project was actually the

forging of the titanium sphere. Because we built the sphere

with the ultimate objective the vehicle will go to

6,500 meters, it had to be able to withstand pressures

at 6,500 meters.

One of the requirements was that it be

as close to perfectly spherical as possible. It was forged

in Wisconsin, into two hemispheres, and then those two

hemispheres were electron beam welded together in

California. And an electron beam weld had never been done

on three inch thick titanium before.

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One of the really big improvements that was needed was

more view ports, with at least the scientists and the

pilot each having a window with an overlapping field of

view so they could actually see the same thing and talk

about what they were seeing.

And the view ports are also larger.

And the view is spectacular.

So when Alvin goes down it's very quiet, and it's

pitch dark. Except for all this stuff around you. And that's

a really humbling experience to think about sort of this

vast ocean filled with things, we don't know what any

of them are, we rarely get to see them.

The manipulator arms have been put on hinged brackets

which allows them to fold out of the way of the view ports,

but at the same time it allows them to fold out forward.

[S. Adam Soule] And in the past you could describe it

kind of like a T-Rex of the refrigerator, it had kind of

these short arms and couldn't get to the stuff in the back.

These new shoulder joints allow it to really have an

improved reach.

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[Humphris] I think the one discovery that really attracted

the attention of the public was Alvin's investigation of the

Titanic. Alvin went back in '86 and actually took a lot

of the imagery that we all now know

and Alvin is very famous for.

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[Girguis] It really remains to be seen where humankind

goes with these deep diving subs. There really is nothing

like seeing the environment first hand. Other nations are

building their own subs, such as Japan, Russia, China and

India, and France I should add. So there's been a lot of

talk about this sort of deep sea arms race and if anything,

all that's doing is pushing the technology envelope on these

human occupied vehicles and making it so that they're

more sophisticated and capable of doing the kinds of science

that we'd like to do.