US Navy News and updates

[FormerDirtDart]

I think your assumption that the commercial Austal trimaran design and the Independence design are identical is totally incorrect. The bow of the Independence is of the "Wavepiercer and the main hull is of the Tumble home designs. ...

The Independence classes central hull is most certainly not of the tumblehome design, the entire length of the hull increases it's beam, and length above the waterline. In ship designing, the tumblehome is the narrowing of a ship's hull with greater distance above the water-line. The DDG-1000 Zumwalt class is a tumblehome design. So is the Advanced Electric Ship Demonstrator (AESD), Sea Jet, which is essentially an operational scale model of the Zumwalt.

 

[db2646]

The Independence classes central hull is most certainly not of the tumblehome design, the entire length of the hull increases it's beam, and length above the waterline. In ship designing, the tumblehome is the narrowing of a ship's hull with greater distance above the water-line. The DDG-1000 Zumwalt class is a tumblehome design. So is the Advanced Electric Ship Demonstrator (AESD), Sea Jet, which is essentially an operational scale model of the Zumwalt.

Thank you for the correction. I must be referencing the original NAVSEA original experimentation design?

 

[alexsa]

Thank you for the correction. I must be referencing the original NAVSEA original experimentation design?

Really you said

The bow of the Independence is of the "Wavepiercer and the main hull is of the Tumble home designs. The only similarity between the commercial Austal trimaran and Independence is the "trimaran" designation. Even the outside configuration of the two vessels are different. The Longitudinal, traverse, and vertical centers of gravities of the Independence vs the commercial Austal trimaran are completely different.

Which I have suggested is rubbish, but clearly stated the center hull was a tumble home design. Tumblehome in Eyres is defined as " the inward curvature of the side shell above the summer load line". The summer load line being the maximum normal draft (it gets less in winter and winter North Atlantic and more forgiving for tropic zones ................. zones are designated in the Load Line convention). Effectively the ship slopes inward at the side shell from it normal draft (i.e the waterline). Tagget says the same thing (which is not surprising).

By NAVSEA design do you mean "Sea Shadow"

If so this is not a tumble home design (that is reserved for conventional hulls) rather it is a derivation of a SWATH hull form. Much more attractive and with better design for low RCS than SWATH (Small Waterplane Area Twin Hull Designs) that have been built for the USNS ...... i.e:

.............. but it is not a tumble home.

http://www.hnsa.org/seashadow/doc/seashadowASNE.pdf

She was a derivation of the SWATH design but was no racing yacht with a max speed of 13 knots and a economical speed of 10 knots.

Even SWATH hulls do not like being submerged beyond design draft as your increase the submerged area and bring the main hull into the equation. Submerge that in a wave and performance is going to change dramatically. SWATH designs normally have the main hull (bridging structure) well above the design water line

 

[justsomeaussie]

Thank you for the correction. I must be referencing the original NAVSEA original experimentation design?

http://www.navsea.navy.mil/nswc/carderock/seaframe/issues/SEAFRAME-Vol1-Iss2.pdf

 

[Bonza]

Now that you admitted that you made an error, maybe, just maybe, it means that you're NOT always correct and you're just human after all? Nobody is perfect all the time? I could probably get in big trouble with the moderators for asking you that question?

You're the one bringing us into it, do you want us to get involved? It's a serious question, I can't help but see an attitude that prompts you to be pushing on nearly every post you make. Alexas is old enough to take care of himself. I wouldn't even be responding to this if it wasn't for your final sentence. Don't bring it up and surprise surprise, it won't be an issue...

 

[colay]

The Navy appears to have pulled a rabbit out of it's hat, projecting the cost of developing procuring 22 AMDR systems to just over a third of it's previous estimate.

NavWeek: AMDR -- Pulse Check


Technology advancements, Small says, have not only made the AMDR just as – or even more – capable as hoped, but at a much more affordable price tag, Small says.

The AMDR’s total price tag will be about $5.8 billion, says a recent U.S. Government Accountability Office (GAO) report, compared to the $15.2 billion projected last year.

 

[justsomeaussie]

The Navy appears to have pulled a rabbit out of it's hat, projecting the cost of developing procuring 22 AMDR systems to just over a third of it's previous estimate.

NavWeek: AMDR -- Pulse Check


Technology advancements, Small says, have not only made the AMDR just as – or even more – capable as hoped, but at a much more affordable price tag, Small says.

The AMDR’s total price tag will be about $5.8 billion, says a recent U.S. Government Accountability Office (GAO) report, compared to the $15.2 billion projected last year.

The sad part is the US could of used the development of AUSPAR to seed the S Band variant but far far to many senators in big US contractor's pockets.

 

[StobieWan]

The Navy appears to have pulled a rabbit out of it's hat, projecting the cost of developing procuring 22 AMDR systems to just over a third of it's previous estimate.

NavWeek: AMDR -- Pulse Check


Technology advancements, Small says, have not only made the AMDR just as – or even more – capable as hoped, but at a much more affordable price tag, Small says.

The AMDR’s total price tag will be about $5.8 billion, says a recent U.S. Government Accountability Office (GAO) report, compared to the $15.2 billion projected last year.

Interesting -about the X band bit being done by a modified SPQ-9B - I'm puzzled, seems they're relying on a rotating radar for that, fixed panels for the S band end ?

Either way, much reduced power and cooling requirements over the original plans so that takes the strain off the Flight III Burke design as that'll no longer be pushed so heavily for power margins.

I need someone with a brain cell to explain to me how AMDR will work vs SPY-1? I get that it's plugging into AEGIS in any event, but what the physical antennae will look like, and how they'll work... ?

 

[justsomeaussie]

Interesting -about the X band bit being done by a modified SPQ-9B - I'm puzzled, seems they're relying on a rotating radar for that, fixed panels for the S band end ?

Either way, much reduced power and cooling requirements over the original plans so that takes the strain off the Flight III Burke design as that'll no longer be pushed so heavily for power margins.

I need someone with a brain cell to explain to me how AMDR will work vs SPY-1? I get that it's plugging into AEGIS in any event, but what the physical antennae will look like, and how they'll work... ?

It's a replacement for the SPY-1. Think of the SPY-1 family is based off 1970s analogue passive arrays and AMDR will be digital and active. That *should* mean lower power and coolant requirements due to a more efficient radar since it isn't blasting out as much unwanted radiation. The digital beamforming means each radar element (or likely small groups of elements) can effectively operate as a radar own their own allowing you to track far more targets.

The simple thing is, like a F22/F35 and CEAFAR you'll be dealing with the analogue to digital conversion as close to the radar face as possible, that means you have huge amounts of capabilities for post processing giving a significant increase in the fidelity of your picture.

 

[colay]

Interesting -about the X band bit being done by a modified SPQ-9B - I'm puzzled, seems they're relying on a rotating radar for that, fixed panels for the S band end ?

Looks that way, at least for the first dozen units. The new gen X-band has been moved down the road as a separate program and it's cost should be separate from AMDR.

“The X-band portion of AMDR will be comprised of an upgraded version of an existing rotating radar (SPQ-9B), instead of the new design initially planned,” GAO notes. “The new radar will instead be developed as a separate program at a later date and integrated with the 13th AMDR unit.”

There are 22 planned AMDRs.

 

[Resolute]

Carriers are they obsolete or not

Hi All,

I came across this interseting document where Captain Hendrix argues about the advantages and disadvantages of using Aircraft Carriers.

The publication is in CNAS.

Some of the key points are:

A saturation attack by 10's of DF-21D may sink a carrier or atleast disable it

The money spent oc carriers is better spent on UCAV's since they are limited only by their own endurance and not human endurance.(humans cannot withstand beyond particluar G limits)

My own opinion is that:

1. If I can completely dominate the electromagnetic signals and Information Spectrum then I will most likely limit the number of actual hits by DF-21D to near zero

2. It has been proven by Red teams of US forces that UCAV's can be hacked and controlled

In any case it is a interesting read Cheers Resolute.

 

[justsomeaussie]

Hi All,

I came across this interseting document where Captain Hendrix argues about the advantages and disadvantages of using Aircraft Carriers.

The publication is in CNAS.

Some of the key points are:

A saturation attack by 10's of DF-21D may sink a carrier or atleast disable it

The money spent oc carriers is better spent on UCAV's since they are limited only by their own endurance and not human endurance.(humans cannot withstand beyond particluar G limits)

My own opinion is that:

1. If I can completely dominate the electromagnetic signals and Information Spectrum then I will most likely limit the number of actual hits by DF-21D to near zero

2. It has been proven by Red teams of US forces that UCAV's can be hacked and controlled

In any case it is a interesting read Cheers Resolute.

I'm not exactly sure how anyone completely dominates the spectrum. Any mass barrage or active jamming ends up just hitting friendlies. Can you elaborate how this would reduce DF-21 attacks?

That's true about any modern "connected" aircraft. It's purely down to the security of the comma link. Your F22 and F35 are still going to be vulnerable if someone could get inside this link.

 

[Resolute]

I'm not exactly sure how anyone completely dominates the spectrum. Any mass barrage or active jamming ends up just hitting friendlies. Can you elaborate how this would reduce DF-21 attacks?

That's true about any modern "connected" aircraft. It's purely down to the security of the comma link. Your F22 and F35 are still going to be vulnerable if someone could get inside this link.

By dominate I mean, make my network so secure that the possibility of the enemy trying to hack into it is either very tedious or time consuming. My network will have several layers of protection and back up.

I also have very powerful offensive electromagnetic capabilities which will cripple incoming missiles while shielding my own platforms.After all there is a reason why the F-35 radars are so powerful.

 

[justsomeaussie]

By dominate I mean, make my network so secure that the possibility of the enemy trying to hack into it is either very tedious or time consuming. My network will have several layers of protection and back up.

I also have very powerful offensive electromagnetic capabilities which will cripple incoming missiles while shielding my own platforms.After all there is a reason why the F-35 radars are so powerful.

Ok. Well ill just leave this with a couple of points.

1. Making your own network secure is everyone's goal but all cryptography can be broken. So just saying words doesn't actually achieve anything.

2. The F35's radar is a radar not a jammer. What if you couldn't jam the DF21 or another weapon because it wasn't able to be jammed? Since you don't have a DF21 to test, how would you know if you could?

 

[Resolute]

Ok. Well ill just leave this with a couple of points.

1. Making your own network secure is everyone's goal but all cryptography can be broken. So just saying words doesn't actually achieve anything.

2. The F35's radar is a radar not a jammer. What if you couldn't jam the DF21 or another weapon because it wasn't able to be jammed? Since you don't have a DF21 to test, how would you know if you could?

Yes it is theoritical but far from impossible.As i said earlier even if enemy understands that trying to hack into the network is very tedious or difficult it still is an advantage in war.

We don't necessarily have to have the exact enemy's missile to simulate and perfect our own systems.We need something that is better or is similar in many parameters.

 

[Todjaeger]

A saturation attack by 10's of DF-21D may sink a carrier or atleast disable it

One thing which at present remains theoretical is whether or not a DF-21D could even hit a maneuvering CVN/CBG.

Such a weapon would need a terminal guidance system which is capable of maneuvering and either an on-board sensor suite and/or datalinks with in-flight updates from accurate offboard sensors.

Given the sort of sensor footprint which a CBG can have (nevermind feeds from other US assets), I believe that the CVN would be aware of something like an MPA getting close enough to produce targeting data.

Then there is the whole question of whether or not the ballistic missile could maneuver sufficiently to perform the required course corrections.

While the potential of such a weapon must be kept in mind, at present it does not seem like a 'game-changer'. That may change in the future, but does not appear the case for now.

-Cheers

 

[Resolute]

One thing which at present remains theoretical is whether or not a DF-21D could even hit a maneuvering CVN/CBG.

Such a weapon would need a terminal guidance system which is capable of maneuvering and either an on-board sensor suite and/or datalinks with in-flight updates from accurate offboard sensors.

Given the sort of sensor footprint which a CBG can have (nevermind feeds from other US assets), I believe that the CVN would be aware of something like an MPA getting close enough to produce targeting data.

Then there is the whole question of whether or not the ballistic missile could maneuver sufficiently to perform the required course corrections.

While the potential of such a weapon must be kept in mind, at present it does not seem like a 'game-changer'. That may change in the future, but does not appear the case for now.

-Cheers

Hi Todjaegr,

It is captain Hendrix who has suggested that a saturation attack by DF-21 could sink or disable a carrier, Not me.

I well understand that the US is already working on several ways to disrupt the DF-21 killl chain. cheers.

 

[Todjaeger]

Hi Todjaegr,

It is captain Hendrix who has suggested that a saturation attack by DF-21 could sink or disable a carrier, Not me.

I well understand that the US is already working on several ways to disrupt the DF-21 killl chain. cheers.

I know. I was pointing out that at present, the 'threat' presented by a DF-21D saturation attack is a theoretical one, and that there are some real questions as to whether technical issues which would need to be resolved before an ASBM attack would be a viable threat.

Some commentators on defence matters tend to look at new/upcoming weapon systems and treat them like 'silver bullet' systems, while ignoring the supporting systems which either support the new weapon system, or would be used to oppose it.

In this case, the ballistic missile which the DF-21D was based off of has a CEP of ~50 m IIRC. That is against a stationary target. Using the same or a very similar sort of ballistic missile against a maneuvering vessel at sea adds in several additional variables which would be inclined to reduce the chances of a hit, beyond what a CEP of 50 m already does.

To ignore the need for the incoming ballistic missile/warhead to be able to maneuver to adjust for changes in the position of the target, and particularly the difficulties in being able to have something on a ballistic trajectory maneuver, is to overstate the threat.

At the same time, the PRC has not demonstrated the sort of broad area maritime surveillance capabilities which would allow mid- to long-ranged warshots at a CBG.

All of this is without the US devoting resources to making it more difficult to target USN vessels. I fully expect that the US is carefully watching Chinese ISR developments, along with ballistic missile technology, to see if the capability is or becomes real.

-Cheers

 

[Belesari]

Don't know why thats so hard to consider for some. But then I'm sure when the first bow was used in war some guy was standing there leaned over and said, "you know..this spells the end of all war with swords and spears right...won't happen anymore!".

Or like the RPG/ATM leading to the ending of all tanks...The Nuke leading to the end of all conventional war etc.

.............................................

Some commentators on defence matters tend to look at new/upcoming weapon systems and treat them like 'silver bullet' systems, while ignoring the supporting systems which either support the new weapon system, or would be used to oppose it.

.....................................

All of this is without the US devoting resources to making it more difficult to target USN vessels. I fully expect that the US is carefully watching Chinese ISR developments, along with ballistic missile technology, to see if the capability is or becomes real.

-Cheers

 

[Belesari]

I seem to remember reading about the LCS-2 class being lengthened to increase bunker capacity. Not sure if there were other considerations or what.

But that may not just be due to be due to hull form and it is hard to assess that without information on bunker capacity and engine fuel burn figures.


But in fair conditions and 'efficient speed of 18 knots' they get a fair range....... but this is a great deal less than the 6000nm at the same speed by the ANZAC class.