As naval observers and analysts, we need a solid grounding in naval history. The Navy is currently in the process of designing and building an ?ASW? frigate, the Constellation class. Functionally, the WWII analog to the Constellation would be the Buckley class destroyer escort (DE), the iconic DE of WWII. Let’s refresh our memory about the Buckley class DE and see how it compares to the Constellation.
The Buckley was an ocean going, anti-submarine (ASW) vessel. As such, it was optimized for ASW and, more importantly, minimized for ASW. Huh? Minimized for ASW? Yes! This is another way of saying that it had a single, primary purpose as opposed to being a multi-function design. It was built for ASW and nothing else (hence, the minimized statement!).
Here’s a brief comparison of the Buckley and the Constellation FFG.
5500 @ 15 kts
6000 @ 16 kts
Role - DE’s were intended to be ocean-going ASW vessels, providing escort for convoys and acting as dedicated submarine hunters (often as part of escort carrier hunter-killer groups). Notably, they were not normally carrier and battleship group escorts – that role being generally filled by destroyers.
Constellation is, presumably, intended to be the Navy’s main ASW surface ship although the limited numbers render that intent nearly irrelevant barring a massive wartime construction program. Unfortunately, the Constellation design also attempts to be an area anti-air warfare (AAW) ship with VLS, Standard SM-2 Blk IIIC missiles, and SPY-6 Enterprise Air Surveillance Radar (EASR) and an ASuW ship … in other words, it’s a do-everything, mini-Burke that is not specialized or optimized for anything.
Design Focus - As mentioned, the DE was a very focused, limited design. Nothing was added to the design that was not absolutely required for the role. One of the key aspects of the design was the recognition that the DE’s combat risk was limited due to the role’s reduced likelihood of combat. The reduced combat risk allowed for reduced armor, reduced armament, and reduced sensors. Contrast that with today’s attempts to include every capability, sensor, and weapon on every ship which, automatically, makes every ship over-spec’ed and over-priced.
Numbers – Because the DE was a focused, limited design, they were cheap and several hundred were built in WWII. Enemy submarines will go to great lengths to avoid detection (translate: mission kill) and the DE’s large numbers allowed them to be everywhere and hindered submarine operations by their mere presence as much or more than their actual combat actions. In contrast, there are only 20 Constellations planned and they’re likely to cost $1B+. History suggests that even this meager number of ships will be reduced. Twenty ships – if that – are not going to be much of a hindrance.
Range – It is noteworthy that the Buckley is half the size of the Constellation and has the same range. We’ve forgotten what we were once capable of designing in a ship!
Size – Buckley’s focused and minimized design allowed a much smaller size; compare the Buckley to the Constellation’s much greater size which equates to much greater relative cost for what ought to be the same mission as Buckley.
Armament – A direct comparison between the Buckley and Constellation is meaningless as the weapons are from different eras but it is interesting to note the weapon density of the Buckley:
- 3x 3"/50 guns
- 1x Bofors twin 40 mm gun
- 8x 20 mm Oerlikon AA guns
- 1x Hedgehog, 24 round, 144 rounds total
- 200x depth charges in stern racks and eight K-gun depth charge throwers
- 3x 21-inch (533 mm) torpedo tubes in a triple mount
While we can’t directly compare the weapons of the two classes, it is, as we said, worth noting the weapon density of the Buckley and that density is hammered home by examining photos of the ship which show weapons mounted in almost every available space. WWII ship designers understood that numbers of weapons mattered and Buckley had every weapon it needed and in sufficient numbers. In contrast, the Constellation lacks one of the main ASW weapons, the VL-ASROC, and has only a single close in weapon, the RAM, with only 21 rounds per use. The Buckley’s 3x 3”/50 guns (76 mm) put the Constellation’s single 57 mm gun armament to shame.
The Buckley class had the same speed, range, and role as the Constellation but was half the size, or less. What’s wrong with this picture?
What’s wrong is that the Constellation is unfocused and, therefore, large and expensive (only building 20!). Yeah, but it can fill multiple roles! No, not really. The area AAW role, for example, will be filled by the Burkes, not the Constellations so what’s the point of giving them an area AAW role? It just increases the size, complexity, and cost of the Constellation.
The Buckley was an example of a focused design that was optimized for its intended role of ASW and, as a result, was cheap enough to risk in battle and cheap enough to procure in large numbers. In short, the Buckley was an excellent example of intelligent naval force structure design. It was everything it needed to be and nothing it didn’t. We would do well to take that lesson to heart.
The Constellation program, in my opinion, is in direct response to the failure of the LCS and a desire to get anything better as quickly as possible into service.ReplyDelete
As to the AAW vs ASW focus, Navy logic dictates that since most of our enemies have aircraft but not submarines, we need an overmatch and nothing in the other...
"The Constellation program, in my opinion, is in direct response to the failure of the LCS"Delete
Yes, as discussed here: "Constellation"
"As to the AAW vs ASW focus, Navy logic dictates that since most of our enemies have aircraft but not submarines, we need an overmatch and nothing in the other."Delete
That seems to be the plan, but it strikes me as an absurdly stupid one.
As a plankowner on LHD-1, I was very dismayed at the dearth of weapons standard aboard the ship. Even the simple crew served weapons weren't terribly plentiful. They have since increased the meager number of defensive weapons, but, not substantially. There is always a price to pay to learn the lessons required to equip a warship properly and it is paid in the lives of those aboard. It is a terrible price to pay, however, it is even more terrible that it a price paid in the past that we are shouldn't have to relearn.ReplyDelete
You've nailed it. These are old lesssons, already bought and paid for and the Navy is ignoring them. You're absolutely correct that we will have to pay the blood price again to relearn them.Delete
I still think the Navy sees the FFG(X) as a cheaper, less capable, numerical AAW replacement for the Ticonderogas. I don’t think there is ever going to be a CG(X). Otherwise, why go to such trouble to get AEGIS onboard?ReplyDelete
The FREMM was a pretty decent GP escort, a bit short of VLS cells, but the Navy added 40 feet of length which should have allowed sufficient room to address that issue.
I will repeat, in my opinion the surface/escort force needs 4 types of ships:
- True cruisers, based on the Des Moines hull, which would give room to larger guns (2x2 or 2x3 8”), more VLS cells (including potentially up to about 16 larger cells for something like supersonic/hypersonic Russian Shipwrecks or SRBMs or IRBMs), and a deck and hangar area for operating a number of small UAVs, plus USVs and UUVs over the side
- AAW destroyers, which could be Burkes or upgraded Burkes
- GP escorts, which could be FREMMs, but more like the original FREMMs (with the increased number of VLS cells for VL-ASROC, Standard, and NSM) than the AAW FFG(X)s
- ASW frigates, basically ComNavOps’s ASW escort, which would be the conceptual heirs to the Buckleys, Knoxes, and Perrys.
I’d build them and operate them in squadrons of 10—1 cruiser, 2 AAW DDGSs, 3 GP DEs, and 4 ASW frigates. I’d accompany each CVBG or SAG/HUK group with a full squadron (operating that many ships in a group would initially present a challenge to today’s Navy, but they’d learn how). If we had 12 CVBGs (1 CVN, 1 CV) and 8 SAG/HUK groups (1 BB, 1 helo carrier) we would need 20 squadrons (200 ships) to provide each group with a notional squadron. Obviously in wartime they would not necessarily operate that way, but that would be an approach to making sure we had a decent number, and they would benefit significantly from training together in peacetime.
At $3.5B for the CG, $1.8B each for the AAW DDG, $1B each for the GP DE, and $500MM each for the ASW FF, each squadron would cost about $12B. That means you could build a CVBG with escorts—1 Nimitz ($9B), 1 CV ($6B), and 1 escort squadron ($12B)—for $27B, or about the cost of 2 Fords with no escorts. And I know which option I’d rather have. Obviously, all those costs are estimates, based primarily on CBO’s numbers, and like all estimates they could grow, but I’d bet on being able to hold the line better for 12 ships with basically all proved technology than for 2 Fords with state of the art technologies that still don’t work.
To cut down on operating costs, I would plan to rotate them—10% of the time in major maintenance, 30% of the time in reserve (reduced manning) status, 30% of the time in home fleet training, and 30% of the time in deployed/deployable status. For additional personnel, I would cut admin/overhead headcount in half and free up about 22,000 personnel for shipboard duty and 11,000 for combat support.
If I was tasked with putting together the navy's surface ASW fleet I would do something like this:ReplyDelete
My primary ASW vessel would be a blue-water frigate like the one CDR Chip described in the comments section of the "LCS Crew Size" post, weighing in around 5500 tons full-load.
They would be fast enough and capable enough to escort the Carrier and Surface Battle Groups. The Cadillacs of ASW.
To supplement these I would have three types of corvettes, the Chevrolets of ASW:
A blue-water corvette with hull sonar, a towed array, torpedoes, RBU, one Phalanx, one SeaRAM, and one 76mm gun. No helicopter.
Maybe around 2000 tons?
For every 5 or so of those corvettes I would have a larger corvette that could carry an ASW helicopter. These would be added for escort duty to supplement the other corvettes that don't have helicopters and aren't sailing with a helicopter carrier. Something along the lines of a Kamorta class.
The third type would be a smaller vessel optimized for brown-water ASW.
I think those ships would cover the surface ASW needs.
I like your Cadillac/Chevy designation, fits with my High/Low concept. As noted above, I was thinking of about 80 of the blue-water frigates, would like to get the size down to a little bigger than the Knoxes/Perrys, around 4500-5000T. They would be the primary fleet ASW escorts and would be fast enough to keep up with carriers. Probably CODLOG so it could use gas turbines to keep up and switch to electric for quiet running to hunt subs.
I was also thinking of about 30 of the Kamorta types for coastal/littoral work and convoy escort.
For the corvette escort roll, I kind of like the small 'cheap' idea that CNO suggests with the historical DE example.
I'd want to keep it small and limited to keep the unit cost down so as to have more of them.
I think that it would be nice to have some ASW helicopters on all of them, but I think it would add too much to the corvette cost to set them all up that way.
And not every convoy would be able to have a helicopter carrier, those would probably be in the hunter-killer ASW groups.
So adding a few Kamorta class type of corvettes to the mix would give that helicopter ASW capability to the group.
But I don't think they could all be of that larger Kamorta type as it would be expensive and reduce the overall number of corvettes.
"For every 5 or so of those corvettes I would have a larger corvette that could carry an ASW helicopter."Delete
"Kamorta class type of corvettes to the mix would give that helicopter ASW capability to the group."
For all you helo-toting corvette enthusiasts out there, remember that a corvette is limited as to the number and size of helo(s) it can carry. The Kamorta class, for example, carries a SINGLE Ka-27 style helo which is half the size of a SH-60 Seahawk type, can only carry a single torpedo, and has smaller payload. Unless you want to build frigate size corvettes, you're going to be limited to small to medium size helos which, by the way, the Navy doesn't have! The SH-2 Seasprite was the last small/med helo the Navy operated and those have long since retired.
Beyond that, a ship with a single helo is a ship with almost no helo. Helos are notorious for maintenance and being unavailable. A corvette with a helo would have that helo in the air for only one or maybe two sorties of a 2-3 hrs each per day. That's 4-6 hrs of coverage out of a 24 hour day and that's being optimistic. There are going to be many days where the helo is down for repairs and maintenance and can't fly any sorties.
So many people seem to have a vision of 24 hr continuous helo coverage if a ship has a helo and that's not even remotely true. A good rule of thumb is an average of ONE 2-3 hr sortie per day.
So, before you go assigning helos to corvettes and one or two helo-corvettes to a group and think you've provided total helo coverage, consider the preceding points.
I don't really know how the navy runs it's ASW helicopters.Delete
In my mind I would think that they would only be launched if there is a suspected contact, to help box in the enemy sub, and I would think that their high speed relative to ships and subs would make them very valuable.
What I'm trying to figure out is how to get even a limited amount of helicopter ASW support to convoys to supplement the lower tech corvettes without needing to have a dedicated helicopter ship tagging along with a merchant convoy.
But I wouldn't want to add that capability to the corvettes either as that adds size, weight, crew, and ultimately cost...which would defeat the purpose of large numbers of ASW escorts available for non-battle groups.
Something like the Kamorta type would seem like it would be a good addition, but it sounds like even that isn't big enough to fulfill that helo capability.
And if a ship needs to be bigger than the Kamorta, it starts to become a frigate.
"What I'm trying to figure out is how to get even a limited amount of helicopter ASW support to convoys to supplement the lower tech corvettes without needing to have a dedicated helicopter ship tagging along with a merchant convoy."Delete
I would offer the usage of ESBs, that would serve as cheap helicopters escort carriers. An ESB in its current state could carry 4 helicopters in its landing spots and 2 additional in the hangar. Using CNO's example above, we should get around 12-18 hours of coverage on a good day for the price of $650 millions per ship (not counting the helicopters itself). An issue you might want to consider is the nature of the ship's survivability as it is essentially a converted tanker.
Additional information can be find here: https://www.forbes.com/sites/davidaxe/2020/08/01/big-ugly-dock-ship-could-replace-the-us-navys-burned-up-bonhomme-richard/#529e16c22957
" I would think that they would only be launched if there is a suspected contact"Delete
You've just asked the key question which is how would helos be used (CONOPS, as we continually harp on!)? When we had S-3 Vikings, they acted to search the route well out in front and surface ships supplemented them with passive detection. Helos were used for inner zone search and attack. Now, we have no 'far front' detection an only have surface ship passive detection. We COULD use helos for slightly in front search but then that risks not having helos available for attack or, conversely, if we keep the helos in reserve then we have to far frontal search capability.
As far as convoys, the same thoughts apply. Unless you have dozens of helos, you can't really sustain a far front search. You can compensate, to a degree, with more numerous ASW ships. Or, you can do like the WWII convoys and conduct ASW on a largely reactive basis which means the enemy subs kind of get a free first shot. ASW on a shoestring budget has no good options!
"ASW on a shoestring budget has no good options"Delete
Abandoning the S-3 Viking without a replacement seems to have taken away options in a lot of areas too.
"Abandoning the S-3 Viking without a replacement seems to have taken away options in a lot of areas too."Delete
An incredibly dumb move IMO. We can't cover the whole world with P-3s/P-8s, particularly not with the numbers of each, and a carrier long-range ASW/patrol capability would be extremely useful.
I have been told that the S-3 ASW suite is considered outdated. Seems to me we have three alternatives:
1) update what we have,
2) keep the airframe but gut and replace the hardware/software, or
3) design and build a replacement.
Even if we don't do any of those, it would surely seem that having something is better than having nothing.
I would like to see a squadron of 12 S-3s (or replacements) on every carrier, 6 in the ASW/patrol mode, 5 as tankers, and 1 as COD.
Is the Constellation-class nothing more than a band-aid on a sucking-chest wound? The LCS was a mistake as was the Zumwalt DDGs It appears to me that the Navy is not exactly certain it knows what it wants. If they are dead set on a dedicated ASW Frigate, why did they not consider the Royal Navy's Type 26 City-class ASW Frigate (Global Combat Ship or GCS is the program name)? These are the specifications for the City-class:ReplyDelete
General characteristics (City class)
Type Anti-submarine warfare frigate
Displacement 6,900 t (6,800 long tons; 7,600 short tons), 8,000+ t full load
Length 149.9 m (491 ft 10 in)
Beam 20.8 m (68 ft 3 in)
1 × Rolls-Royce MT30 gas turbine
4 × MTU Type 20V 4000 M53B high-speed diesel generators
2 × electric motors
Speed In excess of 26 knots (48 km/h; 30 mph)
Range In excess of 7,000 nmi (13,000 km) in electric-motor (EM) drive
Boats & landing
craft carried 2
Complement 157 (capacity for 208)
3D radar - Type 997 Artisan
Kelvin Hughes Ltd SharpEye navigation radar
Terma SCANTER 6000 2D X-Band navigation radar
Sonar 2087 (towed array sonar)
Ultra Electronics Type 2150 bow sonar
& decoys IRVIN-GQ DLF decoys
12-cell VLS for 48 Sea Ceptor anti-air missiles
24-cell Mark 41 VLS for Tomahawk, VL-ASROC, CAMM or ESSM (quadpacked), and anti-ship missiles.
1 × 5-inch 62-calibre Mk 45 naval gun
2 × 30 mm DS30M Mk2 guns
2 × Phalanx CIWS
2 × miniguns
4 × general purpose machine guns
Accommodation for two helicopters:
Wildcat, armed with;
4 × anti-ship missiles, or
2 × anti-submarine torpedoes
20 × Martlet multirole air-surface missiles
Mk 11 depth charges
AgustaWestland Merlin, armed with;
4 × anti-submarine torpedoes
Large Chinook-capable flight deck
Facilities for UAVs
Flexible Mission Bay
Rolls-Royce Mission Bay Handling System
It seems much closer to what the USN actually needs. The continual improvements to the capabilities of AEGIS and the Standard Missile family, why burden an ASW platform, using space that could best be utilized for ASW capabilities, with long-range SAM's? Isn't that why we have the numerous Arleigh Burke's?
A caveat to my original post. The standard US Mark-32 SVTT of one on each side could be added as well as eliminating the TLAM's and add NSM launchers for a surface defense capability. The Mk 110 57mm is not going to scare anything above a SEA DOO.Delete
Type 26 costs more and isn't in the water after a generation.Delete
Thing being, the Navy WASNT dead set on an ASW frigate... I wish they had been, but when they created a mini-Burke, clearly they werent thinking ASW-centric. This was a great opportunity to build an optimized, focused warship. But they failed.Delete
"These are the specifications for the City-class:"Delete
If you do an exact copy/quote from another source, please remember to credit it. This appears to be a Wikipedia copy?
My apologies on the omission for credit of the source. I want to say yes that it was Wikipedia.Delete
To evaluate a Constellation Class frigate, we need to understand for what it is designed. Usually, Navy wants frigates can independently perform limited battles thus Navy want them can do everything although nothing is perfect. LCS were designed on this thinking except then, Rumsfeld, etc. thought that US would only face low tech low power enemies.ReplyDelete
This time, a key question is - who are the potential enemies? From its top speed, we know that this ship is not suitable to be part of a carrier group. Certainly, this frigate is not suitable to fight near Chinese coasts.
Navy have learned lessons from LCS. Rather than plan to use new underdevelopment weapons, Navy uses known systems. At the same time, Navy has planned for its future upgrade. For instance, a Constellation can generate same electricity as a much larger Burke. Limited amount of electricity makes upgrade Ticonderoga very expensive. Advanced radars consume lots of electricity!
So, we should not just lament its fire power vs its size. Rather, it has large spare capacity for future upgrade. Of course, worrisome thing is defense industry's R&D capabilities appear lower and lower. In past two decades, most R&D ended up in failure.
"...a Constellation can generate same electricity as a much larger Burke. "Delete
"Rather, it has large spare capacity for future upgrade."
Heres the problem I see with celebrating all that. First, any excess power generation will be used for what?? No room for more/larger radar arrays, but maybe future directed-energy stuff?? That's generally for self defense, and since its already an Aegis ship, does it really need it? Sure that could allow a more offensive missile loadout, but with the small number of cells aboard, how much is truly gained? Second, the Navy has a poor track record for implementing those "planned future upgrades", and basically, once a class is done building, with some admittedly noteable exceptions, "what you see is what you get". So if a ship doesnt have things from Day One, chances are it probably never will. So designing in significantly extra unused capacity, to me is wasteful. Especially considering the other track record the Navy has built, of early retirements. So ill respectfully disagree, and lament firepower vs size, because history shows us we can do much better!!
Would note that though both the Burke Flt III and Constellation can produce ~12MW of electric power, Burkes power purely for its weapon systems, SPY-6 etc and hotel load.Delete
Constellation power required for its HED propulsion and weapon systems/hotel load. A guess Constellation to hit its max 16/17 knots in HED mode requires ~8 MW?, leaving 4MW for its weapon systems and hotel load, one third the power of the Burke (Fincantieri did offer to up the power to 16 MW replacing the four 3 MW DGs with 4 MW DGs)
PS The proposed Navy FY2022 budget for the third Constellation $1,087.9million includes Plan Costs of $131.5 million which understand initial funding for the establishment of the FFG-62 Land Based Engineering Site, LBES, to test the new HED propulsion system, so actual build cost just under $1 billion for the third ship.
The other take away to note from the budget is the Navy only funding one ship as in FY2020 and FY2021, original Navy program was one in FY2020 and then two per year, so already slipped 40% behind build schedule. Waiting to see the new Navy five year build plan, its been delayed, normally comes with the Presidential budget, will see if they plan to up the build rate.
The budget games theyre playing are somthing else. The budget was also a Burke short, but Congress will add the funding for it anyway. I bet we wish we all had employers that would just add more money when we dont manage our finances properly!!Delete
"includes Plan Costs of $131.5 million which understand initial funding for the establishment of the FFG-62 Land Based Engineering Site"Delete
From the description in the budget docs, it is not clear to me that the construction for the LBES is included in that amount. It might be or it might just refer to the cost for planning efforts, as the category title suggests. One could expect the LBES costs to come out of the Navy R&D budget, as the Navy did for the first two LCS. Do you happen to have a more definitive statement about the LBES funding source?
"any excess power generation will be used for what?"Delete
I think that Navy has learned hard lesson so they need to prepare some spare capacity for possible future upgrade. Chinese navy does well in this front. For instance, while they added towed sonar to type 056 to become o56a, there was no any issue.
If Constellation uses out all its potential to load sensors and weapons, then, in future upgrades, you can only swap or face prohibitly high cost of upgrade power system together. It is not a waste to leave some spare. Even now, in war time, Navy can add some modules to them.
Constellation is not designed to use 10 year but a long haul. You never know what new technologies will be down the road.
"I think that Navy has learned hard lesson so they need to prepare some spare capacity for possible future upgrade."Delete
Have you read any of the posts on modernization and early retirements? I ask because you seem to be totally ignoring history which demonstrates that the Navy almost never does these kinds of upgrades so your comment is completely unfounded.
"includes Plan Costs of $131.5 million which understand initial funding for the establishment of the FFG-62 Land Based Engineering Site"Delete
"Exhibit P-5c, Ship Cost Analysis: PB 2022 Navy Date: May 2021 Appropriation / Budget Activity / Budget Sub Activity: 1611N / 02 / 1 P-1 Line Item Number / Title: 2128 / FFG-Frigate FY 2020 FY 2021 FY 2022"
"Remarks: The changes from FY 2021 to the FY 2022 request are due to the completed Component Cost Position and the Detail Design and Construction contract award. Plan Costs: Changes from FY21 to FY22 account for program Component Cost Position and establishment of an FFG 62 Land Based Engineering Site (LBES). Change Orders: FY22 increased to account for technical baseline changes pursuant to Buy American"
As you would have expected LBES to be funded from R&D budget not SCN.
Financially, US is no longer what impressed most veterans. Price of weapons grow way out of control but ability to pay them simply cannot cope.Delete
Rein in cost is vital or down the road, you can find US Navy becomes smaller and smaller.
While todays DDs dwarf WWII examples, and at some point, comparisons are apples and oranges, I was curious about some basics, so did a little surfing about propulsion plants. And found somthing interesting. The LM2500 engine/genset, at 13x48, could be used in the Buckley hull!! At 107 tons each, versus the 81 ton boilers, the total plant weight would probably be a wash once the turbines, piping, other tanks and accessories are added in. So generally speaking, a Buckley-sized hull COULD have Burke power!! To be fair, I think thered have to be increased bunkerage, as the mpg is probably less. Other factors like the modern weapons and sensor systems could account for the huge size and displacement gains from WWII designs to todays, but at least the powerplant can not be blamed.ReplyDelete
As an interesting footnote, and recalling many previous comments about small ship habitability and seakeeping, a large group of Buckleys were converted to fast transports, trading their 3in guns for two 5in guns, and berthing for 160+ troops!! Yet they still kept their torpedo and depth charge armament!!Delete
Contrast a transport Buckley in terms of speed, armament, and troop capacity with the Marine's Light Amphibious Warship and you see just how poor today's designs are! A transport Buckley would have twice the troop capacity, twice the speed, and hugely more armament! We've come to settle for so much less in our ship designs today.Delete
I was wondering how long it'd be before that comparison came up!! Certainly makes for an easilly damning statement on where we've ended up, doesnt it?? Ive heard so often how you cant make these old/new comparisons, but I totally disagree!! Between the lack of urgency and an abandonment of any appropriate weapons density, our shipbuilding has gone waaaay off the rails!!Delete
Remember the Froude number! The speed listed not not match with with the length given.ReplyDelete
Which speed? We've covered two vessels.Delete
If you think there's a problem, why don't you describe the hull speed calculation to us and demonstrate the problem? That would be helpful and informative.
Froude # = V / sq root(g l). L=lwl in feet V=speed in knotsDelete
Buckley listed at 306 feet means a Fr of 23.44 knots
Constellation @ 496 has a Fr of 29.84 knots
I am suspicious that the real, as opposed to stated, reason for the length of the Constellation class has more to do with Froude # than damage control.
I'm not a naval architect but there's something wrong with your example. Froude number, as I understand it, is a dimensionless number, meaning it is not a speed in knots.Delete
From your formula, you can solve for V, the speed in knots but then the formula becomes
V= Fr * sqrt(gL)
but, this requires knowing the Fr. What value did you use for Fr and where did it come from? I'm assuming you used g=32 ft/s*2 ?
Where did you hear that the Constellation class length has to do with damage control and how would length impact damage control?
As CNO and others have stated, our current warship designs are relatively de-weaponised. This is acceptable, so long as every likely opponent fields equally de-weaponised ships. However, the first opponent to judge there is advantage in prioritising firepower will do so.ReplyDelete
There are a number of historical analogies. The clearest I can see is the pre-Dreadnought battleships. With the coming of the Dreadnought class in 1906, that every pre-Dreadnought ship was considered to be obsolete and vulnerable.
The first Power to design and launch the modern equivalent to the Dreadnought might once again render existing navies, if not obsolete, then at least less important. Pre-WW1 Germany succumbed to temptation and started an arms race, but was in the end out-built by the greater shipbuilding capability of the UK. Unfortunately for the US, the situation is reversed today.
I do not believe that it is certain that arms races make conflict more likely. But I am reasonably sure they don't make conflict less likely. Our current state of naval design encourages an arms race, and does not reduce the risk of conflict long-term. I would argue that this lies at odds with our stated goal of avoiding war.
The US has a long history of, understandably, avoiding developments that disadvantage it. For example, it spends more effort on designing better body armour than designing better bullets. However, this practice is based on a lengthy recent history of the US being able to out-build everyone else if it's technological bluff is called. With the current ratio of China vs US shipbuilding capability, the US inevitably relies more on it's pre-built fleet, and can less afford less efficient peacetime designs.
What is interesting is that the last UK pre-Dreadnought mounted 4 major offensive weapons (12 inch guns) on a 15,358 long ton hull. HMS Dreadnought mounted 10 such guns on a 18,120 long ton hull, a much better ratio. Even back then there were major design compromises that reduced firepower.
The history of the design of HMS Dreadnought has many analogies that still ring true today.
If you go to the Fleet Structure tab above, ComNavOps has proposed what strike me as two very useful ship typesReplyDelete
60 Destroyer Escorts (ASW Escort) – Provides open ocean ASW escort to carrier, amphibious, surface action groups, and logistics convoys.
· 1x 76 mm Super Rapid STRALES/DART
· 2x Mk32 Triple Torpedo Launchers
· 2x RBU-ish ASW rocket depth charges
· ASROC trainable box launcher
· Hull mounted multi-frequency sonar
· SQR-20 Multi-function towed array
· Wide aperture lightweight fiber optic sonar array, consisting of three flat panels mounted low along either side of the hull (Virginia class side arrays)
40 ASW Corvettes – Provides ASW for shallow water, choke point, harbor defense, and convoy escort. This is not a battle carrier or surface group escort.
· 1x 76 mm Super Rapid STRALES/DART
· 2x Mk32 Triple Torpedo Launchers
· 2x RBU
· Hull mounted multi-frequency sonar
· SQR-20 Multi-function towed array
I call them ASW frigate and corvette, respectively, in my fleet proposal, and conceptually would work off a stealth-ized Perry for the frigate and a Kamorta for the corvette, while considering a few modifications:
- I don't like single shafts for combatants, so I'd modify the Perry hull and power plant to have 2 shafts and a 30-knot capability to keep up with task forces;
- I like electric power for quiet running, so I would see if I could fit a CODLAG/CODLOG or IEP plant into at least the frigate; might have to live with diesels and 25 knots for the Kamorta corvette;
- The MK-32 torpedo launcher cannot really be reloaded underway, so I'd prefer fixed tubes like the Knoxes, with a sub-like torpedo room with reloads; with homing torpedos, you don't really have to aim them; I'd consider stacking a 324mm tube over a 533mm tube in order to carry some bigger torpedos that carry a bigger punch and offer longer range
- Instead of the ASROC box on the frigate, I'd prefer some VLS cells; working off a Perry template, I'd move the 76mm gun to the fo'c'sle with the RBU-ish launchers behind it, and try to fit as many VLS cells where the gun mount went; a typical loadout for a 32-cell VLS might be 32 ESSM quad-packed, 12 VL-ASROC, and 12 VL-NSM, so it would have significant self-defense as well as ASW capability;
- As far as high weight, lowering the gun should give a break on weight, and extending the superstructure out to flush with the hull for stealth should create some interior space that might let me lower the superstructure somewhat;
- Because of the capabilities of helos for ASW, I'd keep the 2 helo deck and hangar from the Perrys; in my days, every ASW force commander wanted them because of the two helos and tail;
- I really like the idea of the Virginia arrays, if they can be mounted low enough on the hull to avoid surface noise
Anyway, those are the things I would consider, but I think ComNavOps is right in the ballpark with what we actually need. I have proposed 80 of the ASW frigate and 30 of the corvette, but the numbers of both could move around a bit.
The Kamorta carries a single helo, and ComNavOps's comments about helo reliability are noted. But I don't think the corvettes would usually operate singly, and having 4 corvettes would give 4 ships and 4 helos, which should ensure 1 or 2 helos are available the vast majority of the time. Helos can cover a lot more territory in a short time than surface ships.Delete
Let's say for convoy escort you used one of the frigates and 4 of the corvettes. That would give you 5 ships and 6 helos. You should be able to get pretty good coverage with that.
"4 corvettes would give 4 ships and 4 helos, which should ensure 1 or 2 helos are available the vast majority of the time."Delete
It depends on your definition of available. Using the numbers I threw out, a single helo is available 4-6 hrs/day so for 4 helos that would provide 16-24 flight hours of coverage per day. So, you'd get an optimistic 24 hrs of A SINGLE HELO COVERAGE and, more likely, less than full coverage.
Note what I just said even about the best case: A SINGLE HELO of coverage. If you only encounter one possible (or real!) contact at a time, that will work. HOWEVER, in combat, you'll get multiple possible contacts ALL THE TIME and no commander can afford to ignore a possible contact, no matter how unlikely, in a real, shooting war. One helo (at best!) isn't going to cut it!
That means either accepting a degree of risk by accepting periods of no coverage (not completely unreasonable or unavoidable in war) or increasing the number of helos significantly by providing a helo carrier or many more helo carrying ships. There's no good solution but this also emphasizes why it is SO IMPORTANT to minimize the cost of each individual ship so as to maximize the number of ships you can build and field. Thus, your desire to include VLS on a low end ASW corvette is highly questionable since it will reduce the number of ships you can buy. Remember, VLS costs will include the cost of not just the VLS but the higher end radar(s) to conduct the search/targeting, a higher end fire control of some sort, more operators which means more berthing, heads, galley, food and water storage, etc. There's so much more to adding weapons than just finding an open deck space.
By the way, have you checked to see that your proposed trade between the weight of a 76mm gun and a 32 cell VLS are roughly equivalent? I haven't looked but I suspect the VLS is much heavier. If so, you're introducing stability issues. Just something you might want to look into.
"5 ships and 6 helos"
Six helos gives better coverage than four (24-36hr coverage) but it's still quite limited.
"The Kamorta carries a single helo"Delete
As I noted, it carries a single small/med helo which the Navy doesn't have. What helo are you envisioning using? And, if it's a smaller helo, that might adversely impact even the poor availability I cited!
As I have said before, it's all tradeoffs and the cost (both monetary and otherwise) of each option has to be weighed against the benefits. I laid out a laundry list of proposals, and realistically I would expect some to be adopted and some rejected, but I do think all are worth considering. Keep in mind that where I am coming from is that I want to see much greater weapons density on USN ships and am trying to figure out ways to accomplish that. However we resolve the tradeoffs had better involve a lot of war gaming, and as much live game play as possible.Delete
I think any serious ASW platform needs at least one helo, with a possible exception for very small coastal/littoral shallow-water ASW, and as you have noted, two helos are substantially more effective than one. The tradeoff is what you give up to make room for the helo(s), but if you are focusing on ASW I think having helos wins most of those tradeoffs. Somebody posted somewhere (don’t remember whether it was here or WarOnTheRocks or CDR Salamander or elsewhere, and I can’t find it now, but it had some big vertical bar charts with sub wins in blue and surface ship wins in red if anybody remembers) an Australian simulation study of ship versus sub encounters. IIRC it compared an Aussie Adelaide class with and without helo versus a Burke with two helos and versus a helo carrier with multiple helos. The Adelaide without a helo fared very badly, with one helo slightly better, the Burke with two helos actually won 60% of the time, and the helo carrier did quite well. That comports pretty well with what ASW experience I had over 20 years ago. I’m still searching, and if I find it I will post, but for now, responding to a few of your comments:
“Thus, your desire to include VLS on a low end ASW corvette is highly questionable since it will reduce the number of ships you can buy.”
As I thought I made clear, I am not proposing VLS for the low end Kamorta-type corvette, but for the Perry-type ASW frigate. I would plan to deploy them in outer screen rings for either battle groups or convoys, and thus would want them to have at least minimal self-defense capability against all threats, if nothing else until help could arrive.
“By the way, have you checked to see that your proposed trade between the weight of a 76mm gun and a 32 cell VLS are roughly equivalent?”
Stability is a function of both weight and height. I would expect that the VLS would weigh more than a single 76mm, but the center of gravity of the VLS would be considerably lower than that of the 76mm on the Perry, plus I would lower the 76mm a couple of decks. Also extending the superstructure out to the sides for stealth creates a fair amount of additional enclosed space on the main deck, so perhaps the 01 level superstructure can be reduced substantially, again to minimize high weight. I always wondered why we built ships with what looked like so much wasted space in outside passageways when extending the superstructure flush with the hull would create a fair amount of interior space that could have served to relocate stuff like CIC/Ops Room lower in the ship and reduce superstructure height. Stealth seems to be driving us in that direction, and that is a good thing.
“As I noted, it carries a single small/med helo which the Navy doesn't have.”
Well, they don’t come much smaller than the Wessex Wasp and the Royal Navy got pretty good service out of them, usually one per ship, for two decades plus, including a win against a sub in combat. We would obviously need to develop a smaller helo for use on a Kamorta-clone, but we would have time and at least a starting place by starting with the SH-2 or reverse engineering the HAL Dhruv.
“Six helos gives better coverage than four (24-36hr coverage) but it's still quite limited.”
I would obviously propose doing a lot of war gaming and live training to determine the optimum mix and tactical employment.
I don’t propose to have all the answers, just offering ideas for consideration
My recollection from the mid-1980s is that every surface commander planning any kind of ASW exercise wanted as many Perrys as he could possibly get, because the combination of two helos and a tail made them our most effective ASW platform. The Knoxes were designed to be the primo ASW ship, with their state of the then art bow-mounted SQS-26 sonars, but the operators in the fleet preferred Perrys. With that in mind, my priorities in planning any ASW frigate would be two helos and a tail.Delete
I really, really like the idea of the Virginia side arrays, if that can be done on a surface ship. And I really, really like CODLOG/CODLAG or IEP propulsion to allow running in the much quieter electric mode when actually searching for or prosecuting subs. I originally hated the fixed torpedo tubes on the Knoxes, but came to realize that 1) with homing torpedos, original launch azimuth is not so critical and 2) they could originate in a sub-like torpedo room to facilitate reloads. The combination of a 324mm tube over a 533mm tube is my own idea, out of wanting to be able to launch something with longer range and a bigger punch. And if it's going to be operating in the outer screen ring, 30 miles from the main body, or leading the screen for a convoy of merchants, I would want it to have at least some minimum self defense capability against air and surface threats, enough to hold the fort until help arrives. And of course, I would want CIWS, either SeaRam or Phalanx or both.
I suppose the lowest priority for me is the gun. If needed to save weight, I could be dragged kicking and screaming into supporting a 57mm, or perhaps eliminating guns altogether except for CIWS.
For the corvette, I don't think that size ship can support two helos, but I would still like one, even a small one. I can probably push that into the nice to have category, but if Kamorta can carry one then it can clearly be done. The one question I have not addressed is whether the corvette sonar should be optimized for shallow water ASW. To the extent is would be used in coastal/littoral areas for choke point and harbor defense duties, optimizing sonar for shallow water would be useful, but that would presumably be a negative for convoy escort ops.
That's kind of how I am reasoning through my suggestions.
This comment has been removed by the author.Delete
And if anybody else can recall that Aussie simulation article, I would appreciate it if you could post a link. It's bugging the crap out of me that I can't find it and apparently did not save a copy (which I usually do). I think I have read it within the last week or so, and something tells me that I actually found it by rereading an earlier thread on rather than somewhere else. But I think it would be useful to post a link here for comment.Delete
You just designed the Constellation! An ASW frigate is not tasked with area air defense. It's only AAW need is self-defense. The maximum it would need is an 8-cell VLS (32 quad packed ESSM). More than that is just increasing the cost and size of the ship and creating an expensive mini-Burke like the Navy is doing. Division of labor is how to control costs.
"Aussie simulation article, I would appreciate it if you could post a link"Delete
I think this is what you're referring to: ASW Simulation
The 'simulation' was performed using a computer game, ‘Command: Modern Air/Naval Operations’, a successor to the famous Harpoon series of games. The person who performed the simulations created a truly unrealistic one-on-one scenario in which the sub and ASW were constrained in a 'box'. He ignored the presence of ASROC, among other things. There was nothing operationally realistic about the scenario.
All it did was demonstrate that helos are useful for ASW. It did not consider mission kills, mission priorities, calling reinforcements (as would happen in any submarine detection), avoidance, or any other operationally realistic response. It was an artificially contrived, one-on-one shootout using a video game (though a good one considering it uses only public domain information!).
"You just designed the Constellation!"Delete
No, I did not.
First of all, I did not include AEGIS, which adds a bunch of cost and high weight.
And what would I do with the 32 cells? 8 for 32 quad-packed ESSM, as you propose, At least 12 for VL-ASROC, which is 50% more than the 8-cell matchbox launcher provides. And up to 12 for VL-NSM for some self-defense against surface threats.
As I said, if it's going to be in the outer ring of the screen, 30 miles from the main body, or screening a merchant convoy with no warship in the center, then it needs to be able to defend itself, at least until help (if any) can arrive.
I laid out my priorities above. I would resolve tradeoffs based on those priorities. The one I didn't mention is that from the propulsion standpoint, I think combatants need two shafts for redundancy, and anybody who is going to accompany carriers needs to be able to do at least 30 knots.
You're confusing 'mandatory' with 'nice to have if you have an unlimited budget'. The primary mission of an ASW corvette is to deter (mission kill) a submarine through simple presence. If it detects a submarine, it calls for support. If, and only if, there is no support available and there is no choice but to engage then it engages. Only the latter, least likely scenario calls for a helo and even that isn't a requirement but a nice-to-have.
In recognition of the ASW corvette's limited capabilities, the goal of the ASW corvette is mission kills, not actual kills. An exception might be a dedicated hunter-killer scenario but that would require a dedicated, highly trained squadron (recall my story to that effect).
The main characteristic of a ASW corvette is cheapness which translates to numbers. Every helo, hangar, flight deck, larger magazine, larger fuel storage, more berthing, etc. that you add makes the ASW corvette more expensive and reduces the numbers you can build.
The ASW corvette does not operate isolated. It is part of a multi-faceted ASW response. It does not have to have a helo and, given its main design characteristic, SHOULD NOT HAVE A HELO.
"I think this is what you're referring to: ASW Simulation."Delete
Yes, thanks, and upon rereading it I refreshed my memory. The Aussie frigate in the simulation was a Hobart class, not Adelaide, and I had the colors in the bar graphs backward.
You are right, it was not a very rigorous exercise. But do you really think it was less realistic than the "war games" that we are making billion-dollar acquisition decisions based upon? Worst case, it has some meaning and relevance. Whatever, I've been pretty clear that results would need to be proved up with actual exercise play (live, not desktop).
And as I said, it comports with my own recollection from the1980s (to be fair I think I remember that better than the bar graph colors from the article, I'm old but not that old) where ASW commanders preferred Perrys with 2 helos and tail over Knoxes with SQS-26 and ASROC and maybe 1 helo.
"You're confusing 'mandatory' with 'nice to have if you have an unlimited budget'."Delete
I said very clearly that a helo for the corvette is a nice to have rather than a requirement (quoting me, above,"I can probably push that into the nice to have category, but if Kamorta can carry one then it can clearly be done"). It's a tradeoff, whatever capability a helo adds versus maintainability versus cost versus numbers. The helo probably comes out on the short end of that comparison, but I don't have enough data to make that call.
"You just designed the Constellation!"Delete
And for the record, I've made it clear that I wouldn't do the Constellation the way the USN is doing the Constellation. I'd prefer the original FREMM for more of a GP role, particularly if you add the FBNW 16 additional VLS cells.
I've posted elsewhere about things I'd do to increase the weapons density of the FREMM. AEGIS is not one of them.
I still think the USN sees the Constellation as the cheaper, less capable numerical replacement for the Ticos. I think that's absurd, but I think that's the plan.
Just an observation:Delete
Does anybody on here truly believe that our Navy and Marine leadership are having the kind of give-and-take discussions that we are having on here? Does anybody believe that if they were, they could be coming up with the level of nonsensical ideas that they are?
"do you really think it was less realistic than the "war games" that we are making billion-dollar acquisition decisions based upon?"Delete
The simulation simply concluded that blindingly obvious conclusion that more helos are better for ASW. Duh. What it didn't address was the multitude of real world trade offs between numbers of ships, costs, mission requirements, support from other assets, etc. THAT WOULD BE USEFUL. To be fair, the 'simulation' made no attempt to do so. It falls on us, the astute readers, to recognize the near worthlessness of the 'simulation' and not accord it any great relevance beyond duh.
"Navy and Marine leadership are having the kind of give-and-take discussions"Delete
I don't think the Navy is having any discussions just because they have no interest or focus on warfighting.
As far as the Marines, the Commandant flat out stated that his vision was NOT up for discussion and the resounding silence coming out the Corps is proof of that.
"I said very clearly that a helo for the corvette is a nice to have rather than a requirement"Delete
You're flipping back and forth. Here's another of your statements:
"I think any serious ASW platform needs at least one helo"
So, is a ASW corvette a 'serious ASW platform' or not? If it is, you're calling for a mandatory helo. If it is not, then there's no need to load much of anything on it in the way of equipment. Presence is sufficient.
I think it should, but it may not always be doable. I would argue pretty strongly for the helo in any discussion of tradeoffs, but if the cost in numbers is too great, then I would have to give in.Delete
A lot of my thinking comes from operating with the Brits in the 1970s when they had helos (Wasps) and we didn't. Even that minimal capability enabled them to do a lot of things that we couldn't.
"Even that minimal capability enabled them to do a lot of things that we couldn't."Delete
I think you may be looking at isolated ships and doing a comparison. We don't fight with isolated ships but with groups and, hopefully, large groups (refer to the various posts on WWII escort sizes!) the aggregate of which will have all the capabilities we need. That an individual ship on detached duty doesn't have a helo and can't do a helo task is irrelevant since we don't fight that way … he said, ignoring distributed lethality idiocy.
Yes, it was largely ships independently. Probably in many cases ships that should not have been operating independently, but that's what we had, so that's what we did.Delete
Maybe this would help you understand my thinking. A helo adds some fraction of the capability of a surface ship, but also adds some fraction to the cost. Obviously but unrealistically, if you can add a helo for zero additional cost, you do it. Equally obviously, but equally unrealistically, if the helo costs as much as a ship, so the tradeoff is one ship plus one helo, or two ships, you don't do the helo.
For the corvette, helo cost (including the space and support and everything else required) probably comes closer to the ship cost, and if the cost of the helo is one fewer corvette, then clearly you don't do the helo. For the blue-water ASW frigate, the benfits of a helo, indeed two helos, seem to be enough to justify the cost in any event. Different people can be of different minds, and reasonably so, but the tradeoffs need to be considered seriously.
I don't think the USN gave reasonable consideration, for example, to the tradeoffs involved in converting the FREMM to the Constellation, and I think we are getting a worse ship as a result. Same for the Fords, the Zumwalts, and the LCSs.
ComNavOps, you can take great satisfaction (as well, I'm sure, as a lot of frustration) from the fact that your forum is probably entertaining more reasonable discussion of the tradeoffs involved in USN and USMC strategy and planning issues than is the Pentagon.
Maybe to state a bit more clearly, if my choice is 50 corvettes without helos or 45 with helos, I probably take the 45 with. If the choice is 50 without or 25 with, I probably take the 50 without. My guess is that the realistic tradeoff point is somewhere in between those two extremes.Delete
"if my choice is 50 corvettes without helos or 45 with helos, ... the realistic tradeoff point is somewhere in between those two extremes."Delete
There's plenty of evidence to answer the question. Take a look at the size of corvettes without aviation capabilities. The Russian Buyan, for example, is 203 ft long, the Tarantul class is 183 ft, the Nanuchka class is 194 ft, and the Malaysian Laksamana class is 204 ft.
Now compare to the size of corvettes with aviation (hangar and flight deck). The Russian Steregushchiy class is 343 ft long, the Israeli Sa'ar V is 295 ft, and the Kamorta class is 358 ft.
So, the addition of aviation takes a basic corvette from around 200 ft to around 300-350 ft. That's a 50%-75% increase in length. As we've seen from the Burke class cost breakdown, the hull and basic construction is, by far, the main cost component and for a corvette that has much less in the way of expensive electronics and weapon systems, that hull/construction cost is probably the vast majority of the total cost. So, very crudely, the addition of aviation imposes a 50%-75% cost increase based on length which would result in a loss of a third to a half or so of the number of vessels. In my mind, that's not a good trade for a class whose main characteristic is affordability and numbers. And, this is before factoring in the cost of the actual helo, extra crew, extra fuel, extra munitions, extra spares, etc.
"So, the addition of aviation takes a basic corvette from around 200 ft to around 300-350 ft."Delete
The Visbys at 239ft/640T have a helo pad but no hangar. The UAE Baynunahs at 239ft/915T have a helicopter deck and hangar. So somewhere around 250ft/1000T looks like the minimum for a small helo. The Kamortas are 358ft/3500T, which I think of more as a small frigate than a corvette. I think of a corvette as being on the order of 300ft/1500-2000T, probably about the size of a WWII DE, and under 1000T would be more a patrol boat.
One counter consideration is that in the convoy escort role, the difficulties of taking off from or landing on a platform that is apt to bounce around in open seas as much as a ship that size will could pretty much ground the helos much of the time. There are a lot of factors to consider, and a number of tradeoffs to be made. Obviously we don't have all the answers, but I do think we are asking at least some of the right questions, which the USN isn't.
The Visby is NOT an aviation corvette since it has no hangar. A landing pad-only works only for operations within one's territorial waters. A Visby could not operate a helo on a convoy, for example. Therefore, the considering the Visby in a discussion of corvette size is invalid.Delete
The Baynunah flight deck is 58 ft long. The SH-60 Seahawk series helos are 65 ft long. Do you see a problem when the helo is 7 ft longer than the flight deck? Even the SH-2G Super Sea Sprite is 53 ft long, leaving a 5 ft safety margin. The Navy is not going to operate a helo from a ship with a 5 ft safety clearance. The Baynunah can only operate some kind of very small, personal, civilian type helo. The Baynunah is invalid as an aviation corvette example.
Therefore, my assessment that an aviation capable corvette is around 300-350 ft stands.
OOP's! My bad. I was confusing Froude # and hull speed. Hull speed, as I understand it is 1.34 times the square root of the LWL. Numbers I gave are close for hull speed.ReplyDelete
We all 'oops' from time to time so don't worry about it.Delete
Regarding calculated hull speed, it is important to remember that hull speed is not an absolute physical constraint that a ship can't get past. It's just the limit of EFFICIENT AND ECONOMICAL speed. The addition of more power will push the ship past the calculated hull speed but doing so enters the region where larger increases in power produce smaller increases in speed - in other words, the region of diminishing returns.
I'm not a naval architect and I'm sure a naval architect would take issue with my simplified explanation but it's basically correct, as I understand it.
So, if a ship has a max reported speed greater than the calculated hull speed, it may just mean that it has excess power or some other factor positively impacting the speed or it may be a case of an incorrect report.
In the case of the Buckleys, I've seen reports of max speed of 24-27 kts. The calc hull speed is, I think, 24 kts so those reports seem perfectly believable. I don't really consider 24 kts to be significantly different than 27. The difference is more likely due to variations in measurement than a real difference.