Friday, May 01, 2015

Mini Crazy Thought: the USS Matthew Calbraith Perry, What the LCS Derived FF/G Circa 2020 Ought to be

The US Navy has been buying rather small corvettes which have been called the Littoral Combat Ships. They are fast and intended to be patrol vessels of a sort to deal with the small swarming squadrons of gunboats or fast attack boats and pirates as well as provide for help when there are disasters, etc. They are quite fast at 44+ knots each. However, they are very lightly armed: in terms of armament, a Cold War Coast Guard Cutter (with Harpoons) would be able to take one out.

There are two flavors of them, the Freedom and the Independence classes.

However, there has been a huge hoolah about the fact they are so weakly armed and so expensive (between $450 million to $500 million each, neglecting government furnished equipment).  This prompted a call to cancel the LCS contract and for a replacement which could fight in a full bore battle rather than be glorified coast guard cutter (though admittedly, if they get the Hellfires actually installed, they will be able to kill things out further...a whole 5 miles).  Keep in mind, the ship they are 'replacing' is the Cold War Oliver Hazard Perry class frigate, which no matter how you slice it, they had far more firepower than either of the LCS.

The Navy as a result commissioned the Small Surface Combatant study to see if a full frigate was affordable and what industry could do.  Lockheed and Austal proposed upgraded versions of their LCS classes.  General Dynamics offered an nonpublic bid.  Huntington Ingalls offered an upgraded version of their National Security Cutter.  The Navy settled on modest upgrades to the LCS classes much to the eye rolling of their critics. 

It got me to thinking, what ought we to do, in my opinion?  

A seemingly segue, but its relevant: the US Navy canceled its Zumwalt class destroyers after ordering three.  They were too expensive is the usual commentary, having suffered through the development/procurement death spiral.  There's another consideration too: the Zumwalts were delayed sufficiently that newer technologies were on the cusp of making their armaments obsolete.  Frex, the Advanced Gun System will be outranged  by the railguns being testing at sea next year and the rounds for the railgun will be $25k each or less: far lower than the AGS'. 

While the Navy seriously needs to get its act together for its surface combatants, like getting a new destroyer and cruiser program started and done within budget and on time while dealing with future threats, I wondered what could you incorporate into a frigate.  And where would you want to start?

It does help if it is possible to use as much as the same equipment as before, propulsion, mechanical and hulls, just to save money.  That would imply an existing hull design.  That in turn, based on politics, means something built in the US.  That means one of the LCS or the National Security Cutter.  The cutter isn't in the navy logistical path, so it ought to be cut based on that.  That leaves us with Freedom and Independence.



The Freedom class is a steel hulled ship (a plus) with some room for growth with minimal changes and its faster than the Independence class (47 knots vs 44).  It has 180 tons which it can accept without adding sections and whatnot.  However, significant changes would need to take place for more.  Its internal volume is significantly smaller than the Independence, too.  However, a lot of the upgrades Lockheed proposed for the SSC variant were spot on.  However, some I'm considering here make that internal volume a significant problem. 

The Independence class is aluminum hulled and slower than the Freedom class.  Its also, in terms of volume, enormous.  It also has a very large flight deck.  It also has the capacity to take 210 tons (vs the Freedom 180) as part of its mission packages.

Due to the volume and more mass to work with, the Independence seems like the best starting place.


The 'proposed' Matthew Calbraith Perry class frigate:


for comparison, I left the Independence class under the 'proposed' Matthew Calbraith Perry class.
sorry, couldn't do a good railgun turret, esp in the front, so I left the old one. 
HEY!  Don't mock my meager image manipulation skills!   
The MCP has an enlarge upper superstructure (adding about 300 tons) allowing for the addition of another LM-2500+ (generating 35 MW of power, adding 100 tons) and its fuel stores.  The LM-2500s already installed are replaced with LM-2500+'s.
The aviation hangar is the same volume, but flight deck shrinks by a third: its still larger than the Freedom class' flight deck.  It retains the two SH-60 ASW helicopters, adds a second Fire Scout, and adds two TERNs. 

A hull sonar is added (probably at this point the same as the Burke's AN/SQS-53C, weighing 26 tons) and the towed sonar array is kept.  An Aegis combat system is added with an SPY-1F array, adding another 20ish tons and requiring 3 MW.

The proposed SeaRAM self protection missile system is kept and an additional 32 Mk 57 VLS cells (72 tons) are added.  I'd speculate you'd have a load out of 16 cells of 64 ESSM (or successor), 8 ASROC (or successor) and 8 LRASM.

For close in ASW problems, two sets of Mk 32 Torpedo tubes would be ideal (or a successor, really).  These would weigh a total of 5 tons.

Here's where things get a little radical.

While our little frigate packs the punch of some destroyers now with the configuration above, it doesn't explain why we needed the volume of the Independence class or the power from the LM-25.  By upgrading the current LM-2500s to LM-2500+'s, we get a enough power for the new sensors (sonar and radar) without sacrificing speed.  However, the new weapons require more power than what could be sacrificed even with the upgrade.  What are those?  Yup, lasers and railguns.

Proposed here is to replace the 57mm cannon with a 155mm railgun, like what is to be tested next year on the JHSV.  The range will certainly be longer 60+ km vs 17 km.  The impact damage certainly higher.  The railgun can also be used in an antimissile capacity.  The rounds are very cheap, relatively speaking.  Amusingly, the railgun itself is pretty light weight: around 15 tons, about the same as the 57mm cannon!  However, its pulsed power system is very heavy and takes up several shipping containers in size.  That enormous mission bay of the Independence ought to be able to fit the pulsed power system.  Additionally, the weight ought not to be over 180 tons.  Together with the railgun itself, this is around 200 tons.

The second 'radical weapon' would be a laser.  I don't mean the LAWS system, but rather a weapon's grade laser (100 kw+) which would be used for both small surface targets and anti air and anti missile roles.  Considering we want to have a very low dwell time, we need a megawatt (erm, really megajoule) class laser.  There are two ways to do this.  Either we can wait for the free electron laser (on track, but going slow) or use a solid state laser.  DARPA's HELLADS laser fits the bill and has demonstrated a weapon already at General Atomics.  One which GA is planning on integrating on its Avenger drone (which I took and ran with).  If we aggregated the HELLADS modules, we can get a megajoule/pulse class laser: you need a total of 20 modules.  If one is half a ton, then twenty is 10 tons more.  If you count in optics, beam director, and extra cooling and power, you're looking at somewhere around 30 tons.  And the power requirements!  Oh the power requirements!  Let's just leave it at 'gimme.'  Okok, each pulse minimally will need 1.2 megajoules and if you plan on having more than one pulse per second you need to multiply the number of pulses you want by the 1.2 MJ.  The absolute most you can get is 22 pulses/second. 

(yes the butchered RAM launcher on the top of the MCP doodle is meant to be a beam director.  stop mocking my art!).

Now the question is, 'how fat did our baby get?'

Truthfully, we have added 750 tons of structure, sensors and weapons.  That pushes our ship to being 3800 tons fully loaded...without the extra fuel for the LM-2500+ for the new weapons and sensors!  Fortunately, even if we are carrying an extra 400 tons of fuel, we are will still be able to eek out another 2 knots from the upgraded engines.

Now how expensive is our baby?  We get roughly a cost of $820 million vs $464M for an Independence class.

So.  Why?  Why do it?  Its almost twice as much as an Independence class LCS.

The first answer it gives the US a huge numerical edge with well equipped, well armed combatants: the Burkes cost $1.8B each.  For five Burkes, you can get 11 MC Perrys.  

Second, you have a ship which act as an escort for an aircraft carrier.  One of the amusing bits is the monster sized aircraft carriers can sprint far, far faster than the escorts can.  The escorts, destroyers, etc, can do around 30 more than 30 knots, but the carriers can do well over 40 knots with the nuclear reactors.  In emergencies, carriers have sprinted ahead and rendezvoused with different escorts at its destination or been forced to be unescorted at its destination.  While the MC Perry is not a Burke in terms of capability, it will have some distinct capabilities: lasers and railguns are rather cheap per shot.  And, this is done without needing to resort to nuclear power plants for your escorts.

Finally, even when the Burkes and Ticonderogas or follow-on replacements are present, these new FFGs add a distinct capability as advanced screening ships like the previous Perry Frigates did for the carrier battlegroups. 

Aren't the laser and railgun a little immature?

If the lead ship, called Matthew Calbraith Perry here, is laid down in 2020 as the SSC plan calls for, then commissioning will take place in 2024.  Ten years from now.  The railgun is most likely going to be replacing one of the Advanced Gun Systems on the USS Lyndon B Johnson, the last Zumwalt.  The USS LBJ will be commissioned in 2021, a year after the laying down of our proposed MCP.  The HELLADS program will have been wrapped up and could, like with LRASM, be transitioned into a procurement relatively easily.  
 


Now, do I think this will happen?  

...

Yer funny.

However, back in the mid 90s, a silly for fun project I did on Usenet caught the attention of the Navy before and they asked me to do a little analysis for them.  I did but didn't take what was offered afterwards.  While I doubt I'll be offered anything here, maybe, just maybe, this might tickle someone with influences own ideas and alter course a bit.  

Maybe. 





Afterword:  its becoming obvious in the coming world of hypersonic weapons and antiship ballistic missiles and potential peer naval powers, a lot of our Navy's kit needs replacing.  I am not talking about the ships: that too.  Rather I am talking about the missiles and whatnot.  The Standard Missile is being upgraded, so less worries there.  LRASM is in play, so good start, but progress towards a VLS launched hypersonic missile is needed.  Likewise for a hypersonic Tomahawk replacement.  The ESSM has a range of 10 miles....that's 10 seconds for a Mach 5 missile and 5 for Mach 10: if it misses or fails to take out the hypersonic missile, you're not getting a second shot at that distance.  

For that matter, ASROC definitely is old and ought to updated if not had a replacement made.   etc. 

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