New stealth destroyer turned over to U.S. Navy, Capt. James Kirk

[Skroe]

Why aren't ships driven with jet pumps instead of propellers?

They're more complicated (and thus more expensive) than propellers, but the real reason is that Pump jets are historically mostly used only for ships that need high speed at all times (such as submarines). Engines that power ships (or anything else for that matter) are most efficeint at a certain output and it isn't desirable to go high speed at all times for endurance/efficiency reasons.

On a DDG-51 Arleigh Burke Destroyer, the ship carries 4x LM2500 gas turbines that power the main propulsion system as well as 3 service turbine generators for ships sytems. 2 turbines are tied to a mechanical drive through the Main Reduction Gear Assembly, that is connected to the shaft and the propeller. The turbines have 2 speeds: off and on. And that's it. To control speeds, the ships turn on or turn off LM2500s... the faster they go, the more they use. At about 18-24 knots, the Destroyer is highly efficient and can go 7-10 days without refueling because it's using 2 LM2500s. At high speed (24-28 knots), endurance is 3 days (3 engaged). At "flank speed", 28-30+ knots, a destroyer can go as little as 9 hours before refueling (4 engaged). However below (15-18 knots) endurance is still `~10 days as 1 LM2500 and one service turbine generator is used. This is highly inefficient.

Presently the Burkes are starting to be refit with Hybrid Electric drives that will power the Burkes below 15 knots, and will add days to their endurance by allowing 2 of the 3 service turbine generators to handle propulsion at that speed and all LM2500s to be turned off.. Integrating a pump jet into this would be counter-intuitive - a surface ship simply doesn't need to go that fast all the time.

In fact, the high speed/complicated propulsion of the LCS class, which has Pump Jets, is one of the big problems with the ship.

More on this: http://www.defenseindustrydaily.com/...to-them-07142/


The Virginia class submarine, the Seawolf class submarine, and the Ohio replacement submarine use (or will use) pump jets. However they're all nuclear. They don't need to be refueled. The Ohio class and Los Angeles class do not use pump jets.

GE is working on it though for surface ships.

http://www.gereports.com/post/745451...-pump-jet-for/

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They should totally transfer him to command of the Ford class USS Enterprise when its commissioned, assuming of course that he's qualified. And if he needs additional training beforehand , get the f on it right now.

Can you imagine being a harbormaster somewhere and getting this over the radio:

" This is Captain James Kirk of the USS Enterprise, requesting permission to dock."

He'll be an Admiral by then, if he is still serving. The CVN-80 (USS Enterprise) won't be launched until 2023, commissioned until 2025 and likely deployed until 2027-2028.

The FY2017 budget by the way includes long lead in time for the Fourth Ford class carrier, after Enterprise. Since America is now a Amphibious Assault Ship, they should go with Midway or Franklin D. Roosevelt, or maybe, just maybe Arizona.

[Hooked]

What do we do with our old destroyers, submarines, and aircraft carriers?

[Kellhound]

The main issues with them is they are under "gunned",over priced, and under manned.

[Skroe]

Yes, as I noted in a later post the truth about the Zumwalt is quite possibly somewhere between the extremes. We can and should expect Russian sources to downplay the Zumwalt, just as we should expect news from the US side to be cherry picked to highlight the most positive aspects of the project. The problems with labor at the shipyards are known, and are cited as a significant reason the cost of production for the Zumwalts has increased substantially.

Concept vehicles have their uses, they just get expensive on the Zumwalts' scale. Even within your own post, you touch on some of the problems this presents. The Zumwalts were a 90s wet dream that may not be up to the challenges of 2020.

Well the US already has lived this with the Seawolf class attack subs. The Seawolfs are different and more capable and advanced in some areas than the Virginia's that suceeded them, but like the Zumwalts, only 3 were produced because they dended up being too costly. The Navy's solution has been to use them where the most potent Submarine threat is, which is the Pacific Ocean. So all three are based in Washington.

It will be the same deal with the Zumwalts. They'll be "problem solvers".


The DDG-21 class design from the 1990s was refined into the Zumwalt design. Like the F-35, the Zumwalts look are one thing, but the most advanced aspects of it are what's inside. That matters. And it's very, very 21st century.

Undeestimate at your peril, what it means for the Zumwalts to be generating 80MW of energy. The Burkes do 8 now (I wrote 9 by mistake earlier, forgot it's 2MW x4 generators, not 3x 3 generators). They'll do 12 with the Flight IIIAs. At 12MW, they'll be able to host a laser powerful enough to shoot down an intermediate or medium range ballistic missile. But to shoot down an ICBM, you'd need roughly a 20-25MW laser. The Zumwalts could host two of those each. So think about what that means when we're talking about a ship that will stay in service for 35 years minimum. The Burkes show that, retrofitting an existing ship with more power generation means putting new generators within the same dimensions. It only takes you so far (a grand total of 4MW over the Flight IIA). No other ship in the world that isn't nuclear will be able to get closer to the Zumwalts power generation, and that's critical since moving to electrical weapon systems is the direction the Navy has been planning for 20 years (similar to how Aegis and VLS tubes were introduced, don't be surprised if ships with lower power generating capacity have short service lives).

As far as the Zumwalt being able to get closer to shore, that's probably great for bombarding Somali pirates. I'm not sure it is an effective trade in terms of the South China Sea.

They'll be able to get in closer than any other destroyer in the world will, and regardless of that, they'll carry more land attack missiles than anything besides an Ohio SSGN. I mean it's either an advanced stealth ship that can get closer, or it hangs back with the rest of our destroyers and just has a truly massive "clip". It's win-win.

The tumblehome hull design is controversial, and one of the issues is that there are questions about how it will hold up to damage.

It was controversial, about 8 years ago. That argument is over now.

The railgun may go a long way towards offsetting the problem the Zumwalts would have in the South China Sea, but as things stand now they would be operating in a comparatively confined space that plays well towards things like visual observation by UAVs tied into missile attacks.

The rail gun is going to see in 2017 on test ships. The third ZUmwalt will be built with it and enter the fleet in 2021. The range of the railgun is sufficient that it wouldn't be in a "confined space". It would also have substantial air defense (including its own).

As you said, the damned things are huge, and the third one (the one that may get the railgun) is going with a steel deckhouse that will probably offer less stealth.

The Deckhouse will be overall more compact because the dual-band radar will be physically reduced in size. This isn't unusual. The USS Jimmy Carter, the last of the Seawolfs, was substantially different from the other two.

What we can know right now is that, given the Zumwalts' design, deploying them in the South China Sea is likely to be seen as increasing an already tense situation. The Arleigh Burkes are multi purpose, the Zumwalts aren't really. Wherever they go, they're the naval equivalent of waving a loaded gun.

China can always back down and abandon it's illegal islands before somebody gets hurt or we evict them. The Cops should have loaded guns after all.

[Skulltaker]

They should totally transfer him to command of the Ford class USS Enterprise when its commissioned, assuming of course that he's qualified. And if he needs additional training beforehand , get the f on it right now.

Can you imagine being a harbormaster somewhere and getting this over the radio:

" This is Captain James Kirk of the USS Enterprise, requesting permission to dock."

"Kirk sucks. Come back when you are Jean-Luc Picard. Permission to dock denied."

[Skroe]

What do we do with our old destroyers, submarines, and aircraft carriers?

A ship... any ship, just like any tank, or your car, has a recurring cost of ownership. For a carrier, it costs about $300 million per year to operate on average. For a destroyer, it's about $40 million give or take. That's the cost of crewing, operating, fueling, and deploying the ship, per year. Everything has this. Your car has this; you call it annual total gas money + annual inspection.


The Navy calculates the total number of deployments every ship it has will get over it's lifetime, stretching 30 years into the future. So for example, the Ohio Replacement program has built zero subs so far, but the Navy already knows that because it will need less maintenance than the Ohio class, that each ship will do ~120 deterrence patrols over their 30 year lives. And they know which ones will be deployed when, through 2070 (roughly).

When ships hit their deployment target, unless the navy decides to overhaul and keep them a while longer (which it does periodically), it retires them to make room on the budget for newer ships, that hopefully are cheaper to own. Reducing recurring cost of ownership is a primary goal of naval procurement at the moment. For example a Ford class carrier costs ~$12 billion, nearly double that of the $6.5 billion the last Nimitz cost just a few years prior. But design changes, fewer crew members needed, shaved off billions of dollars of lifetime of the ship costs.

Carriers are typically dismantled and sold for scrap. The USS America was sunk a few years ago as a test target but that was an exception.

Subs are dismantled. Since they have nuclear cores, they can't be used for practice or sold.\

Destroyers are usually used for practice. About 15 years ago the Navy VERY rapidly retired the Spruance Class destroyer in order to free of money and protect the Areligh Burke destroyer program. The Spurances were a fine ship class, less advanced, but numerous, and could have served until 2020 (this was around 1999 we're talking here, so 20 more years of life). In order to avoid a repeat of that time Reagan ordered a 600 ship Navy and the Navy was forced to reluctantly mothball and retrofit obslete ships, the Navy sunk every single one of it's Spurances within five years. Hard to recommission ships at the bottom of the ocean!

The 4 most advanced Spruances, which had Air conditioning and other advances (the Kidd subclass) because they were originally meant to be sold to Iran pre-revolution, ended up being sold to Taiwan.

The Navy keeps 2 carriers, some destroyers, some cruiser and some supply ships in reserve fore reactivation, usually around 180 days, in a national emergency. It's unlikely that would ever happen though. The USS Enterprise was cut open almost immediately because she was by far the most expensive and complex nuclear carrier in the fleet (being the first and all).

What the Navy needs is a 5000-6000 ton surface combat frigate that doensn't suck and it can build six of a year. Instead we got the LCS Death Trap.

[Kellhound]

The USN just needs a modernized OHP frigate. Simple, robust, effective.

[Skroe]

If you're interested in what the Total Ship Computing Environment is, this is a great article. It's a pretty revolutionary system.
http://arstechnica.com/information-t...ered-by-linux/


Zumwalt's Operations Center


The ship's systems diagram

[Elim Garak]

So how does it destroy stealth?

[Skroe]

The USN just needs a modernized OHP frigate. Simple, robust, effective.

Some of the Freedom Class LCS designs get pretty close. Or hell, militarize the National Security Cutter, which is a better design than either LCS models.

That moment when the Coast Guard gets a better basic frigate design than the Navy.

The Navy not wanting to put VLS tubes on the LCS-FF edition is silly. I'm wondering if it's some black magic to protect Destroyer procurement.

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So how does it destroy stealth?

I don't follow. What do you mean?

[endersblade]

It makes you wonder if he worked intentionally on becoming a Captain, to fulfill, what I'm sure was a lifelong running joke.

I knew an Army grunt named Sgt. Sledge. As in, the G.I. Joe guy. He said he enlisted specifically just to be called that lol.

[Theodarzna]

How expensive are those things should one be sunk?

[Elim Garak]

I don't follow. What do you mean?

Really? It's the stealth destroyer - destroyer of stealth.

[Skroe]

How expensive are those things should one be sunk?

http://www.bga-aeroweb.com/Defense/D...Destroyer.html
$3.1 billion for the first in class.

$21.66 billion ($12.55B procurement + $9.11B RDT&E)

That's what happens when you only build three.... same shit as the Seawolf class, and the B-2 bomber and the F-22. Maybe we'll learn one day.

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Really? It's the stealth destroyer - destroyer of stealth.

I'm dense lol. Good one.

Should be a battleship or "battlecruiser". It's nearly identical in size to some early battleships. It is optimized for land attack like battleships eventually became. Calling it a Destroyer still is bizarre.

Maybe it'll get a late change, like the the "F/A-22" became the "F-22" again the day of entering service.

[Theodarzna]

http://www.bga-aeroweb.com/Defense/D...Destroyer.html
$3.1 billion for the first in class.

$21.66 billion ($12.55B procurement + $9.11B RDT&E)

That's what happens when you only build three.... same shit as the Seawolf class, and the B-2 bomber and the F-22. Maybe we'll learn one day.

That seems rather large for a piece of metal unlikely to ever see any practical use IMHO. Will it ever be used?

[Kellhound]

Some of the Freedom Class LCS designs get pretty close. Or hell, militarize the National Security Cutter, which is a better design than either LCS models.

That moment when the Coast Guard gets a better basic frigate design than the Navy.

The Navy not wanting to put VLS tubes on the LCS-FF edition is silly. I'm wondering if it's some black magic to protect Destroyer procurement.

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I don't follow. What do you mean?

The cutter is too lightly built for combat. The LCS is good for a set of missions as is, anything involving real combat requires a real warship.

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That seems rather large for a piece of metal unlikely to ever see any practical use IMHO. Will it ever be used?

It will be used as much as any other surface combatant in the USN.

[Theodarzna]

The cutter is too lightly built for combat. The LCS is good for a set of missions as is, anything involving real combat requires a real warship.

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It will be used as much as any other surface combatant in the USN.

Have we had any major naval battles lately?

[Skroe]

That seems rather large for a piece of metal unlikely to ever see any practical use IMHO.

Yeah heaven forbid this country spend money on things that aren't grandma's pills or fixing rusted bridges in Tulsa.

But really, it fits a specific military niche very well. The Ticonderoga cruisers, meant for air defense, will be slowly retired over the next 15ish years, and their replacements are the Flight III Arleigh Burkes, at the same time some early Flight I Burkes will retire too. So you'll have multirole/surface combat ships no specializing in Air Defense as the refurbished, newer Ticonderoga's become the air defense leader. So the fleet will need VLS tubes filled with land attack missiles, especially since it will lose 154 tubes per Ohio class sub, when they start retiring around 2030-ish.

DDG-1000 fills a specific niche. It's not the originally envisioned one, but it's a fine place for it. And the Arleigh Burkes have seen tons of use. Chances are these will too.

Sometimes the Pentagon gets it wrong. In the Arleigh Burke, it got it really, really, really right.

[Gorgodeus]

Have we had any major naval battles lately?

Has your house burnt down lately? No? Better cancel your insurance.

[Skroe]

Have we had any major naval battles lately?

The Zumwalts (DDG-1000) are designed around Land Attack, not anti-surface warfare. They can do it, since they'll carry Tomahawks, Harpoons and SM-6s. But they're specialized for attacking targets deep inland in contested areas.

This is going to be the ship bombarding the country in the war you'll be protesting a decade and a half from now, Theodarzna.

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The cutter is too lightly built for combat. The LCS is good for a set of missions as is, anything involving real combat requires a real warship.

I heard and uparmored/upgunned variant was being shopped around the export market.