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gelgoog said:

I personally think it is a waste of money for a boutique submarine class. They would be better off buying more Virginia class.
I doubt the repairs will only cost tens of millions of dollars once all is said and done.

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The Virginias has smaller (maybe half? ) operational envelope and magnitude less capability than these subs.

The USA navy is between a hard and rock place, the Seawolfs the only subs that can reach undersea cables and do other deep diving missions, and there (was) three of them only.


However the cost of repair easly can go up to the price of a new Virginia sub.

Anlsvrthng said:

The Virginias has smaller (maybe half? ) operational envelope and magnitude less capability than these subs.

The USA navy is between a hard and rock place, the Seawolfs the only subs that can reach undersea cables and do other deep diving missions, and there (was) three of them only.


However the cost of repair easly can go up to the price of a new Virginia sub.

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The other issue is that there is no spare capacity to add a new Virginia to the construction queue in the next 10 years.

I think repair costs would be a maximum of one-half of a Virginia, even if the front 2 sections had to be custom fabricated. But the Connecticut is due to retire in 2038 anyway, so by the time repairs are completed, the submarine will only have 13 years of service life left. And that's assuming the Connecticut repair takes up resources and delays new submarine construction.

AndrewS said:

I think repair costs would be a maximum of one-half of a Virginia

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it's unknown.
There is probably no replacement sensor suites in existence, and replacing the original one with a Virginia suite would be both expensive and will come with a significant loss in capability.

AndrewS said:

so by the time repairs are completed, the submarine will only have 13 years of service life left. And that's assuming the Connecticut repair takes up resources and delays new submarine construction.

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The problem is that with modern expansion of PLAN, USN can't really allow to drop its most powerful torpedo boats anymore.
"just 13 years" is just a fiscal side of the question.

Problem is by the available sources the Seawolf use HY-100 steel, the Vriginia HY-80.

And the HY100 way more difficult to weld and fabricate. This was one of the reasons of the high cost of Seawolf.

The most complicated part of the pressure vessel is the front dome ,that needs to be formed in two direction, and that is the part that damaged.

Anlsvrthng said:

Problem is by the available sources the Seawolf use HY-100 steel, the Vriginia HY-80.

And the HY100 way more difficult to weld and fabricate. This was one of the reasons of the high cost of Seawolf.

The most complicated part of the pressure vessel is the front dome ,that needs to be formed in two direction, and that is the part that damaged.

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Presumably possible to replace the dome with HY80 steel at the cost of max operating depth?

The Hull of the Seawolf class is HY100 the Dome of the Sonar is Composites. The Dome is just a faring meant to give the boat an hydrodynamic shape. Like the Nose cone of a Fighter jet it’s built of a material that allows the sensor to function IE as invisible as possible. But because it doesn’t have squishy Humans or oxygen pressure vessels the dome can be made of lighter materials.

TerraN_EmpirE said:

The Hull of the Seawolf class is HY100 the Dome of the Sonar is Composites. The Dome is just a faring meant to give the boat an hydrodynamic shape. Like the Nose cone of a Fighter jet it’s built of a material that allows the sensor to function IE as invisible as possible. But because it doesn’t have squishy Humans or oxygen pressure vessels the dome can be made of lighter materials.

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And so ?

The problem is not the damage of the sonar dome, but the front sphere of the pressure vessel.

The core of the submarine is a pressure vessel, full cylindrical, and with two half sphere on both side.

Sometime it has more than one vessel, or it has different diamaters with complex surfaces between them.


All other stuff, like sonar, conning tower or ballast tank attached to the pressure vessel, with structures designed to keep them in place, but not more structural strength. Neither of them designed to work as a deformation zone to absorb the impact energy, like with cars.


It is the heaviest part of the submarine, means in a collision the other frontal parts has minimal ipact decrease effects, the main front part of the vessel that absorbing the energy.

Anlsvrthng said:

And so ?

The problem is not the damage of the sonar dome, but the front sphere of the pressure vessel.

The core of the submarine is a pressure vessel, full cylindrical, and with two half sphere on both side.

Sometime it has more than one vessel, or it has different diamaters with complex surfaces between them.


All other stuff, like sonar, conning tower or ballast tank attached to the pressure vessel, with structures designed to keep them in place, but not more structural strength. Neither of them designed to work as a deformation zone to absorb the impact energy, like with cars.


It is the heaviest part of the submarine, means in a collision the other frontal parts has minimal ipact decrease effects, the main front part of the vessel that absorbing the energy.

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Quit making up your own facts. That is Bogus. The Hull was not compromised. If that was the case the Connecticut would not have been able to sail home. The Sphere is the Sonar array it’s not the pressure vessel it’s a sensor. The BQQ5D derived from that used on the I668. The nose is a composite faring. Basically she lost her bumper.

TerraN_EmpirE said:

Quit making up your own facts. That is Bogus. The Hull was not compromised. If that was the case the Connecticut would not have been able to sail home. The Sphere is the Sonar array it’s not the pressure vessel it’s a sensor. The BQQ5D derived from that used on the I668. The nose is a composite faring. Basically she lost her bumper.

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Don't be silly.

It is not the wife's subaru ,that drive well with a few mm deformation on the front cross frame.


10 mm deformation on the frontal vessel end (could be expected if it bumped into a brickwall mountain) means the diving deep decreased to the fraction of the original.


The local curvature of the sphere that needs to be calculated.
If it is a mathematical model then the surface local radius colud be calculated with the partial derivate of the function .

The first one gives the normal vector, the second one the change of the direction of the normal vector ( radius )

The longest radius needs to be put back into the vessel equation.

Just for reference, a flat surface has infinite radius ( in Euclid geometry ), means in the above function it will give infinite stress in the wall . Of course the above equation is for thin wall, it considering the wall as infinitely thin. The "real" pressure vessel equation more complex, but for a simple submarine wall calculation it is good enought.


The manufacturer had to cut off the front part of the submarine, and replace it with the front section of another one.

But there is no decomissioned Seawolf.

You are making up facts. We have no idea what velocity the Connecticut impacted at or how direct the impact was. All we know is what she looks like the Sonar sphere is still attached. The nose is gone. Punched in yet the way it was attached that segment was mounted on the outer hull. The damage is to the outer hull. The pressure hull is sound so it’s super structure.

Note that what we see here as well as other images doesn’t show the same level of damage as the San Francisco. What we see is the rear wall of the Sonar dome array.