The US military is building its entire force structure around the concept of information which includes data collection, surveillance, networks, etc. In other words, the military is assuming – or, at least, working towards the goal of – perfect battlefield awareness, believing that will make up for vast, self-inflicted shortcomings in firepower. Setting the lunacy of that assumption aside, the implication is that the US believes that all will be known and seen on the battlefield. Accepting that premise for the sake of analysis and discussion, we must also assume that the Chinese will have the same degree of total vision and situational awareness.
What, then, does that suggest about the survivability of naval forces? It’s obvious, isn’t it? Only the most stealthy platforms will be able to evade detection for any useful time period. Unfortunately, none of our current naval surface ships come remotely close to that level of stealth. In order for a ship to survive on the future naval battlefield, it will need to have maximum stealth across the entire electromagnetic spectrum and beyond. With that in mind, why don’t we have a bit of fun and see if we can come up with a conceptual design for a future ship – it doesn’t matter what type – that is the stealthiest possible given our current level of technology?
Before we go any further, we need to briefly review what stealth is.
While most people associate the term ‘stealth’ with radar signature, the term actually encompasses much more. The definition of stealth is the ability to evade detection. That evasion can include measures such as reduced radar signature, reduced infrared signature, reduced acoustic signature, altered visible signature (camouflage), the use of multi-spectral obscurants, decoys (chaff, flares, emitters), electronic warfare, tactics (avenues of approach, use of weather), etc. It should be noted that some of these do not have to be part of the ‘hiding’ platform’s capabilities but can be provided by other platforms in support of the ‘hider’. For example, an F-18G Growler electronic warfare aircraft can provide stealth cover for other ships or aircraft by using its EW/jamming capabilities to reduce the likelihood of detection of the ‘hiding’ platforms.
Of course, having organic stealth measures helps, too!
So, understanding everything that goes into making a platform – a ship, in this case – stealthy, let’s see if we can conceptually design the ultimate stealth surface ship, just for fun. What would it look like? What characteristics would it have? What unique aspects would be incorporated into this design that are not currently common?
For this exercise, we’ll only consider the organic stealth measures and ignore the off-board measures from other platforms. Thus, we’ll concern ourselves with size, radar signature, acoustic signature, infrared signature, optical visibility, electromagnetic emissions, obscurants, decoys, electronic warfare, and wake suppression. Some of these factors are pretty obvious so, for the sake of brevity, I won’t belabor them.
Size – The most basic – and almost universally ignored – aspect of ship stealth is size. Simple size. All else being equal, a smaller ship is harder to detect than a larger ship. A smaller ship naturally has smaller signatures across the electromagnetic spectrum. This is a fundamental truth that the Navy has totally ignored as it continues to produce ever larger ships. The WWII Fletcher class destroyer was 376 ft long versus a Flt IIa Burke class destroyer which is 509 ft long. A WWII Atlanta class cruiser was 541 ft long versus a Zumwalt class cruiser (the Navy misleadingly calls it a ‘destroyer’) which is 610 ft long. The Brooke class FFG was 414 ft long which was followed by the larger Perry class FFG which was 453 ft long which was followed by the still larger Constellation class FFG which is 496 ft long.
One of the largest drivers of ship size is the Navy’s obsession with helicopters. The Navy believes that every ship must have a helicopter with its attendant flight deck, hangar, magazines, maintenance shops, additional crew, etc. which make up a third of a ship’s length and superstructure. No ship should have a helicopter unless it is absolutely required for the execution of its primary mission. For example, an AAW escort has no need for a helo which instantly reduces the ship’s size by a third – a nice chunk of ‘instant stealth’!
Included in size considerations is the superstructure. Superstructures have grown enormously since the ships of WWII (see, “Ship Superstructures”). Every square foot of superstructure area and every cubic foot of superstructure volume increases the ship’s various signatures.
The obvious conclusion is that our stealthy ship must have the smallest hull size and smallest superstructure possible, consistent with its mission requirements (CONOPS).
Radar Signature – This is the commonly understood measure of stealth and needs little further discussion other than to note that a truly minimized radar signature requires that there be no protruding objects such as railings, sensor domes, antennae, line handling equipment, platforms and supports, cabling, electrical junction boxes, firefighting plumbing, etc., all of which our current ships have in abundance. Our conceptual starting point, in this respect, is the Swedish Visby which is nearly as free of protruding items as possible (see, “Ship Stealth and Visby”).
 |
| Visby - Note the relative lack of protruding objects |
Acoustic Signature – Arguably, the most lethal threat to ships is the submarine and the main means of detection that a submarine uses is acoustic sensors. Our ship must be as quiet as possible. Every known acoustic suppression method must be used, including isolation and rafting of internal machinery, selection of inherently quiet machinery, Prairie-Masker, vibration dampening, cavitation suppression, etc. Silence must take priority over speed. The powertrain and propulsion must be the quietest possible. We cannot use massive noise beacons like water jets. I do not have detailed acoustic data about propulsion pods but I suspect they may be a good choice since they eliminate the use of long, large, noisy propeller shafts and combining gear. I also do not have acoustic data on turbines versus, say, diesel engines.
The point is that the propulsion system must be selected for reduced sound rather than maximum power or speed, again, consistent with mission requirements. This would be a radical departure from current ship design.
Infrared Signature - Ideally, our ship should have a temperature identical to the surrounding ambient air and water. One of the major IR sources is, of course, the hot exhaust from the commonly used turbine engines. If we can’t find a better choice than turbines, we need to, at least, suppress the heat of the exhaust by discharging the heated air through a water mist or exhausting the air into the water[4] or very near the waterline in a water-cooled discharge.
The rest of the hull and superstructure gets hot from internal heat sources and heat absorption from the sun. The hull and superstructure need a cooling system similar to the Nuclear/Biological/Chemical (NBC) washdown system. In this case, instead of washing away radioactive particles, the washdown would serve to cool the ship’s skin and reduce the IR signature.
Optical Visibility – Many weapons use optical sensing for target identification, terminal guidance, and impact point selection. We must reduce or alter our optical signature as much as possible by reducing ship and superstructure size and by applying camouflage to break up or alter the ship’s outline. Interestingly, early WWII Gato submarines had relatively large superstructures which, in combat, were quickly cut down to reduce their visible detectability. We must follow this example. The least detectable superstructure is no superstructure. While that may not be totally achievable, it is the goal we must strive for. We must ruthlessly eliminate any non-combat compartment in the ship. This means no ship’s post office, no gym, no crew lounge, no chapel, no lawyer’s office, etc. This is a ship of war not a cruise ship. Every non-combat space that can be eliminated allows us to reduce the size of the superstructure. I guarantee that every sailor will gladly choose survival in combat over a coffee bar or video game lounge.
An intriguing area for research is the use of adaptive electrochromic coatings/paint that can alter their color, reflectance, and other properties depending on temperature, light and light angles, and electrical state. To the best of my limited knowledge, these are not available for field use but they should be aggressively pursued as near term research projects.[3]
Electromagnetic Emissions – This is our old friend, EMCON. This is well understood and, until very recently, totally ignored by the Navy. I won’t belabor this further other than to emphasize that our conceptual ship cannot have any stray emissions and must be designed to operate without active emissions to the maximum extent possible. This means emphasizing passive detection and tracking of targets versus active. To the maximum extent possible, fire control must utilize passive sensing. Every piece of equipment on the ship must have a verified EMCON mode of operation. It goes without saying that cell phones, video games, or any other personal electric device must be banned.
Obscurants – ‘Smoke’ has been developed that can provide multi-spectral interference (concealment) and can be deployed as any other shipboard decoy canister.
Decoys – This is a vastly under-emphasized aspect of stealth. Not to belabor the obvious but decoys mimic a real target in hopes that an attacking weapon will be fooled into selecting the decoy instead of the real ship. Decoys can take many forms from simple emitters that broadcast the real ship’s radar frequencies to persistent, floating, radar reflecting, multi-faceted ‘igloos’.
Similar to electronic warfare, the Navy has given relatively little attention to decoy research and development. Current decoys are very basic and limited. What is needed is a decoy that simulates radar, infrared, and visible emission characteristics of the host ship and has a useful degree of persistence.
We also need suitable doctrine and tactics for the employment of decoys. For example, the current tiny handful of decoys embarked on ships is woefully insufficient for a high end naval battle. We need to be capable of dispersing hundreds of decoys, not a handful. Let an enemy weapon find the literal one-in-a-hundred signal that is the real ship.
Insert photo: Decoy 1.jpg -multi-faceted radar reflector
Electronic Warfare (EW) – Despite the fact that historical data shows that EW is far and away the most effective defensive technique, the Navy has virtually ignored EW for decades. Even the SEWIP modernization program barely pays lip service to the role that EW should play.
We need powerful emitters for jamming, false signal injection, cyber attacks, etc. and the entire electronic warfare system must be tied into the Aegis combat system so that it acts in a coordinated fashion.
Wake – Our enemies have wake homing torpedoes and no truly stealthy ship would be without wake suppression measures. Unfortunately, wake suppression is technically challenging and I’m not sure if any practical measures have been fielded. The Navy has a patent on a wake suppression technique using ultrasonics to reduce/remove the microbubbles in the ship’s wake which are what allow a wake to be sensed and tracked.[1] Another patent describes a means of reducing wake vorticity (turbulence) by siphoning off the boundary layer of water along the hull.[2]
Design
Having come to an understanding of the various factors that impact stealth, we can now conceptualize a maximum stealth ship design.
The ship will be as small as possible with only a minimal superstructure – think a slanted, stealth version of a WWII Fletcher class destroyer superstructure, maybe less. All surfaces, hull and superstructure, will be fairly sharply angled and will be completely smooth with no protruding pieces of equipment. The ship will, externally, appear to have no equipment or weapons and items that are necessary for ship handling operations will be fully retractable in one way or another.
Sensors will be either embedded flat panels or retractable with an emphasis on passive sensors providing complete and continuous hemispherical coverage with multitudes of redundant and overlapping sensors. Even navigation radar will be omitted. Instead, infrared and electro-optical sensors will provide navigational information. This may force us to become actual sailors again but that’s not a bad thing, is it? Radar use will be limited to active weapons employment and even that will be minimized.
Weapons will be retractable in various ways. Even the ubiquitous Mk41 VLS will be modified with a completely flat cover instead of a multitude of separate hatches, each with its own several-sided radar reflecting surfaces.
Except for specific ASW vessels, there would be no helo facilities.
UNREP gear will be fully retractable.
This ship will require a complete revision in combat operating procedures. The overwhelming emphasis will be on passive sensors and greatly reduced communications (none, during combat). Admirals will have to trust the ship captains to understand their mission intent and then leave them free to execute as they deem best. The constant verbal diarrhea gushing forth from today’s ships will be a thing of the past. This ship will operate unseen and unheard.
Nothing will be allowed on the ship that does not have a verified, shielded, EMCON operating mode. The ship will not emit a single stray electron.
The ship will embrace bad weather, seeking it out and using it tactically for whatever degree of cover it can provide.
The ship will be constantly passively ‘sniffing’ the electromagnetic spectrum for its situational awareness instead of depending on the brute force of radar. The crew and ship’s systems will be constantly a hair’s breadth from active combat. Combat systems will have a full auto mode which will be the standard mode in a combat zone. There won’t be time for human reactions.
The ship will be built for war, not cruising. Silent. Unseen. Stealthy.
____________________________________
[1]https://patents.google.com/patent/US5787048A/en
[2] https://patents.justia.com/patent/5222455
[3]https://gardnerlaboratories.com/2013/11/22/chemistry-corner-more-color-changing-paint-byk/
[4]Discharge into the water will increase the backpressure on the exhaust flow thereby reducing propulsion system performance. This is an example of prioritizing stealth over speed.
Ooohh...fun exercise!! My first thought was simply "submarine"... But Ill dig out some napkins and start doodling!!!
ReplyDeleteYes, a submarine checks several of the stealth boxes but it can't meet many of the mission requirements. Submarines can't provide fire support (of course, neither can current Navy ships!), can't provide presence (to the extent that's a useful thing), can't conduct boarding operations, can't provide anti-air defense, can't deal with swarms, can't provide wide area surveillance, can't act as escorts, can't protect carriers, can't conduct amphibious assaults, etc. so we still need surface ships.
Delete"But Ill dig out some napkins and start doodling!!!"
This is exactly what I don't see the Navy doing and they should be. They should be constantly working on alternative ship designs - this being one example. The General Board did this routinely as thoroughly documented in any of the ship design history books. We should have dozens/hundreds of total stealth ship designs sitting on shelves, waiting for further development ... but we don't, as far as I know. The Navy has totally abdicated its ship design responsibility and capability to industry. Industry has no interest in producing good/alternative designs. Their only interest - rightly so - is the most profitable design - hence, the endless succession of Burkes that are more obsolete with every new build.
Have you looked at 'doodling' on Shipbucket website? It's free, easy, and offers many hundreds of starting points based on existing or imagined ships.
It could be interesting to design a ship that submerges just a little bit to avoid detection and pops up whenever needed.
Delete"design a ship that submerges just a little bit to avoid detection and pops up whenever needed."
DeleteI've thought about that but the problem is that once you commit to a submersible design, the cost/complexity go way up. That simple retractable door that only has to seal out spray and rain now has to be able to withstand pressurized water and that requires much more in the way of strength, materials of construction, and operating machinery. We have to add ballast tanks which adds cost, size, and complexity. And so on.
You're essentially describing a Gato class submarine!
It's appealing but the cost would be astronomical.
Would it really be that expensive? We built 197 Gato and Baleo class subs 80 years ago. Didn't seem that expensive back then.
Delete"Would it really be that expensive?"
DeleteInstead of throwing out unsubstantiated speculation, why don't you find some actual cost data, adjust it for inflation and tell us what a Gato cost. Then add all the electronics, sensors, weapons, etc. that a surface warship would need and tell us the final cost. That would be a productive comment. Thanks!
Mr Archimedes is more likely to be your problem. An extrapolation from his theory is something called TPC/TPI - Tonnes per cm immersion or tons per inch if you prefer. A simple calc shows that a 100m long ship with a 15m beam would need around 15 tonnes of water ballast per cm you wish to submerge. GIven most ships have freeboard of 4m or better for a number of other reasons, reducing that by only a quarter would need nigh-on 1500 tonnes of WB. Which is about three times the amount of fuel a ship of that size would normally carry. Finding space for that - in the right part of the ship - would be an "interesting" exercise.
Delete"Mr Archimedes"
DeleteMr. Archimedes seems quite happy with the Russian Typhoon submarine which is 175 m x 23 m.
That wouldn't be a problem, there's so much volume wasted on pointless amenities on today's ships.
DeleteWhy does a warship need a meeting room, for example?
Mr Archimedes has a mate. He's called Mr Steel. Have a little think as to whether Mr Typhoons pressure hull has sufficient volume to be buoyant. Or indeed what freeboard Mr Typhoon operates at. There's a reason for Mr Typhoons double hull....
DeleteWarships have meeting rooms so that the command can meet - possibly to do things like plan and brief future operations. Alternatively, they also occasionally need to socialise. Those meeting rooms also tend to be in the upper part of the ship for access reasons among others. I wonder what effect putting a large weight of water high up in the ship could possibly have? There's a reason I used the phrase "right part of the ship".
Delete"Mr Archimedes has a mate. "
DeleteClearly large vessels can be designed to submerge. It's been done. Whether you'd be able to fit all the other surface ship features you'd want into a submersible at a cost you'd be willing to pay is unknown. I'm not sure what further point you're trying to make. Either make a specific point or drop it.
"Warships have meeting rooms so that the command can meet"
DeleteTraditionally, those rooms have been called wardrooms. It's amazing how we managed to build and crew a 6000 ship fleet in WWII and win a global war without any of the things we now misguidedly believe are mandatory: meeting rooms, gyms, lounges, coffee bars, lawyer's offices, game rooms, helicopters, Internet for the crew, etc.
On the other hand, we also literally built ice cream barges to supply ice cream to the fleet, and our WW2 carriers had ice cream making facilities...
DeleteOur navy has always been soft, alas.
Ice cream is a necessity. No one would dispute that!
DeleteHmmm. Fairly sure you've never entered a wardroom, nor appreciate the difference between the facilities needed for planning operations and those for eating. They really are quite different.
DeleteAnd yet we did it throughout WWII. Hmmm.
DeleteBy the way, you don't plan operations on a ship. That's done at a headquarters. The operational order is disseminated to the ships and briefed in whatever space (wardroom) is available.
Didn't battleships and cruisers have operations rooms for the Admirals' staffs? I recall Halsey had a staff with him onboard New Jersey (htough what they were doing, I have no idea)
DeleteQED. Lovely theoretical model of how ops are planned and conducted. Doesn't match reality.
DeleteIf the correct model doesn't match our practice then we need to change our practice, not modify ships to accommodate a flawed practice.
DeleteWe've become accustomed to a badly flawed belief that we must have perfection in everything. If we're going to have a planning session, we've come to believe that it can only occur in a fully outfitted, digital, monitor-filled, comm-linked conference room. We've forgotten that we can plan just as well sitting on the ground outside with a map in our lap as long as we're just planning and not trying to show off our Powerpoint presentation skills.
" I also do not have acoustic data on turbines versus, say, diesel engines."
ReplyDeleteI thought that gas turbines are supposed to be relatively quiet. I hope someone chimes in on this.
Carlton Meyer's diesel-electric corvette concept (a real littoral combat ship) is intended to minimize noise.
http://www.g2mil.com/LCS.htm
I don't have a link, but in one of the older discussions on this blog, someone mentioned diesel-electric propulsion for your ASW corvettes.
I like the idea of trimaran or pentamaran warships because they are theoretically more difficult to sink. But I wonder if the outriggers might create more noise than a comparable ship with a monohull.
I was an EW in the 80's, aboard a DD and a CVN. EW and EMCON were NOT "ignored" by the Navy. It could have been better. SEWIP is a great leap in the right direction. We did not have cellphones in the 80's. They have no place aboard warships.
ReplyDeleteI understand that from your narrow perspective (narrow as in your focus was at the individual ship/equipment level as opposed to the world wide state of electronic warfare) you saw the Navy engaging in EW. However, the reality is that the Navy lagged far behind state of the art in SLQ-32 development which was a 1970's era technology that was never significantly upgraded. Even today's SEWIP upgrade, while significant compared to SLQ-32, is fairly limited and minimal with active defense capability still not ready. Most of the SEWIP upgrades are just hardware obsolescence mitigation efforts.
DeleteCompare the glacial pace of EW development to, say, aircraft and missile development which has advanced almost too fast to keep track of. That's what I mean by the Navy ignoring EW.
The one 'piece' of EW that truly fascinates me, if even a fraction of what I've heard and gleaned is true, is OUTBOARD/COBLU. I've talked to two guys who operated with it and they can't say anything specific other than it's an amazing system.
Would you have any interest in doing a guest post on some aspect of EW? I understand that much of what you know is likely still classified but it would be fascinating to get your general thoughts on various aspects of EW as practiced by the Navy.
Thanks for jumping in, here!
I had assumed your pay-off would identify the merits of a wooden sailing ship with a mast that could be hinged down quickly.
ReplyDeleteP.S. "not available for field use" - for goodness sake don't say that near a university.
Wing Sails. Already being used on commercial ships, could made made out of non reflective materials and very light weight. As an example look at the GP sail series boats (old America cup series).
Deletemight I offer up the sterling engine (for electrical generation) and propulsion pods. Very simple and efficient, low noise signature, multi fuel (ethanol would be nice as it is a renewable resource.). The Swedish Gotland class AIP subs use them for main propulsion.
"sterling engine (for electrical generation) and propulsion pods."
DeleteInteresting combination! Like any engine/power source, it has advantages and disadvantages. It sounds like it wouldn't work well in warm seas (assuming it used water for the cooling portion.
chilled water condensers for cooling. the engine pods also have ducted air to them to cool them. Daikin company has super efficient chilled water units that would be great for shipboard cooling needs. I ran the engineering plant at a hospital a few years back, we had two 200 ton units added in. They came in a standard 40 ft. container box. They had magnetic bearing compressors (no mechanical bearings), at 100% load would only pull around 90-100 amps. (standard size York would pull 260-300 amps).Super compact, quiet and reliable.
DeleteGood point on the holy trinity. Stealth feature grow the ship else reduce payload. Need more cooling? Have less gear.
DeleteI think the nav radar still comes in handy during fog in traffic. I doubt anyone is using one in a combat zone. Not to be solely relied upon in any scenario. I think you are right about rethinking aviation to a certain degree. I know there has been talk of not embarking helos on the Zumwalts for this reason. The same point can be made for the boat launch. 11M RHIBs are great for VBSS, but will do plus why does it matter on a large surface combatant that should be off working on other, high end, missions. In the same way you want more decoys, the decoy launchers could just deploy small UUVs and UAVs for additional means of detection. In shrinking the ship, we can introduce the opportunity to try stealthier materials, but we need to understand we are losing the ability to make big changes and probably have a limited service life. Specifically thinking Visby and the potential of a composite ship. In terms of VLS, I'd rather shorten up a mk 57 or just scale down the whole system. In kluging up Zumwalt we have lost the opportunity to appreciate some of the systems that are in it. The guns wrecked it.
ReplyDelete"I think the nav radar still comes in handy during fog in traffic."
DeleteAnd yet sailors managed to operate for centuries without radar! Remarkable.
"probably have a limited service life."
I've pushed hard to 15-20 year service lives for ships. That used to be semi-standard.
Bigger Sea Shadow
ReplyDeletePerhaps. The question is whether you could fit the required sensors and weapons into such a form? I'm also unsure (as in, I have no knowledge one way or the other) about the combat damage resilience of that type of hull form. I suspect (with no specific knowledge) that it would not do well as regards combat damage. Issues like wetted are, reserve buoyancy, stability if one side takes damage, etc.
DeleteBattlefield awareness utilizing what sensors? Passive sensors often lack range and active sensors significantly reduce stealth measures. The sensors need to have a platform to operate from and I would assume those are the same platforms that are trying to remain stealthy.
ReplyDeleteGoing dark is taking a huge risk because if the enemy has detected you that won't be obvious until a few moments/minutes before their strike. If you are going to be forced to use active sensors anyway then your investment in stealth measures isn't going to be of much benefit. Removing the active sensors to another platform or using drones with active or passive sensors could help but that would get expensive fast.
"Going dark is taking a huge risk"
DeleteIn war, EVERYTHING is a risk. Go fast or zigzag? Charge quickly or sneak.slowly? Radiate or remain passive?
"Passive sensors often lack range"
It depends what specific sensor you're talking about. Signals analysis can detect comms halfway around the globe. Passive sonar can, under the right conditions, detect acoustic sources multiple convergence zones away and almost invariably outdistances active sonar. Radar is limited to the radar horizon (15 miles or so) unless the target is elevated. F-14 Tomcats were able to use optical cameras to detect bombers 70-100 miles away. And so on.
" If you are going to be forced to use active sensors anyway then your investment in stealth measures isn't going to be of much benefit."
Active sensors would only be used during an actual engagement at which point it doesn't matter because the enemy has already found you. However, remaining passive prior to that point greatly reduces the chance of being found.
Everything's a risk.
I'm in favor of losing the helo capability but assume you'll keep the flight deck to facilitate VERTREPs.
ReplyDeleteAs long as you're thinking napkins and alternative designs how about trading off stealth for longer range weapons?
What does a SSM with a 3K+ range provide in terms of ocean to hide? Would that mitigate stealth which is costly in terms of not only money but design tradeoffs? Who cares about detectability inside the first island chain? Never have to go there.
What about an arsenal ship the size of a RO-RO fielding 400, 600 or a 1,000+ VLS tubes (hell, that's enough capacity you can throw in AAW, ASROC (yeah, that's old) and anti-surface)? No superstructure and no radar mast; photonics only and dishes capable of receiving surface plots from Global Hawk successor and RORSATs. What if that same ship had a 8-foot, or less, freeboard? Yep, now draft is going to complicate life (and ports)- Nuclear powered, guarded by attack subs (think 2 can provide enough coverage?) and, why not, armor the big SOB to your hearts' content. Or your budgets'-
Nope. No NGFS capability. Not on these.
One of the things we're seeing in Ukraine is the value of standoff weapons which can be launched OUTSIDE of the air defense umbrella. That's why I want lots and lots of missles launched from afar. Mid-course guidance to be provided by other platforms (B-21, satellites, etc.).
I acknowledge that stealth is a good thing. Seems to me it's also so expensive and indeterminately effective (how do I know I'm stealthy enough? oh... I'll know only when I get hit. Or not.)
I worry that pursuing stealth for surface ships is like the Her Majesties 1700s Admiralty asking Larry Ellison for advice on carbon composite sails (airfoils!) to upgrade their Man-of-War mainsails.
And finally, off-topic but you brought it up "The constant verbal diarrhea gushing forth from today’s ships will be a thing of the past.-" I hated the 1MC with a white-hot passion. Damned thing never shut up. Never ever a moment of respite lasting longer than 3 minutes or so.
Just one of the things I'm going to change when I take office. Because, just like COMNAVOPS, I want USN to get its head out of its ass and start thinking about alternatives.
"Weapons will be retractable in various ways. Even the ubiquitous Mk41 VLS will be modified with a completely flat cover instead of a multitude of separate hatches, each with its own several-sided radar reflecting surfaces. "
ReplyDeleteI'm rather fond of how the French Lafayette and Singaporean Formidable FFGs have a take on this - there are six "spaces" which are flush with the superstructure and not open or exposed, so they benefit from the reduced RCS shaping. These spaces are sized to hold quad launchers for ASCMs (in practice 2 of those spaces are used for cranes for the ship's boats).
It seems to me that instead of retractable covers, perhaps it would be better to build a sort of stealth "fence" around the foredeck VLS farm (meanwhile, we can contain the aft VLS within a stealthy superstructure).
I think the idea of smaller stealth ships can only really work for ships with the ASuW/ASW mission; AAW and BMD requires the radars being turned on and sweeping, and that means we can't get away from larger superstructures - SPY-1 panels are 14 feet diameter, SPY-6 panels are said to be 21 feet, requiring the Flight III Burkes and Large Surface Combatant to be much bigger.
It's a pity the Zumwalts mission creeped so hard from the original idea; if they'd stayed as stealthy Spruance replacements, we'd have been much better off.
" better to build a sort of stealth "fence" around the foredeck VLS farm"
DeleteThat might be better than the open arrangement we have now but it's still less than can be achieved. A fence, no matter how effective, is still open from all but shallow angles and whatever it's enclosing would still be visible to radar at higher angles. Remember, this exercise is an attempt to design the ultimate stealth ship not just a decent one. Now, whether the cost/design tradeoffs are worth it is another issue.
" AAW and BMD requires the radars being turned on and sweeping"
NO! Radar is only required for the actual engagement at which point it's not a problem since, by definition, the enemy has already found you.
"21 feet"
Today's superstructures are hundreds of feet long, wide, and tall. Cut all but the panel area away and you'd be left with a minimal superstructure - exactly what the post is calling for.
"Today's superstructures are hundreds of feet long, wide, and tall. Cut all but the panel area away and you'd be left with a minimal superstructure - exactly what the post is calling for."
DeleteThat's what I'm saying - this is one of those tradeoffs that we talk about.
A minimal superstructure means that the ship can't carry 21 foot radar panels for AAW, but if the ship's job is ASuW/ASW, then it doesn't NEED to carry an AAW-grade radar, and a minimal superstructure is a worthwhile tradeoff.
"A minimal superstructure means that the ship can't carry 21 foot radar panels "
Delete?????? If there were nothing but the panel, the superstructure would be an incredibly small 21 ft on a few to several hundred foot long ship. Minimal doesn't mean no superstructure. It just means the minimum required for the primary function. You seem confused. What are you confused about?
Sorry, I didn't make myself clear. What I'm trying to say is that an ASuW/ASW focused ship does not need to carry multiple 21 foot AAW radar panels. We can thus get a significantly smaller superstructure that way, and be even more stealthy, like the Visby in the example picture.
DeleteYes, this is the primary function philosophy that so many people have such a hard time with. Added to the primary function philosophy is the design requirement that says you provide the ship with only the MINIMUM required to execute the primary function. Most people want to provide the ship with the maximum they can fit on it but that only serves to drive up the cost and reduce numbers.
DeleteYou pick a primary function and then you provide the MINIMUM outfit required for that function. Thus, as you correctly say, an ASuW or ASW ship does not need a full, max size radar suite.
A concern I have is the evolving missile threat. Depending on when and where we're fighting the Chinese, within the next 10 to 20 years they're going to have multiple carriers and air wings online, and their MPA fleet and naval bombers will be expanded: it is not inconceivable that the PLAN will have the capability to generate saturation attacks with hundred-plus missiles.
DeleteI'm not confident that relying on a few Aegis DDGs in the flotilla is going to provide enough of an umbrella, especially if the Chinese use their ASBMs in concert with the ASCM attack to form an additional attack axis - at some point, what we consider an AAW grade radar today may well be the cost of entry in 20, 30 years from now. (I'm reminded of how the Perry's radar, modest by 80s standards, would have been a gamechanger in WW2, just 40 years earlier.)
"a few Aegis DDGs in the flotilla"
Delete????!!!!! No sane naval commander is going to enter a combat zone with just a few escorts. We've thoroughly examined this. See, "Escorts"
No sane naval commander, sure - but given the readiness rates of the Navy, are we really going to have the numbers of escorts we need? As your own post acknowledged, we have about 80 Burkes and Ticos, which is only really enough for two task forces - and that assumes we're able to get all our ships surged into combat. Given the current trends in our shipbuilding, will we still have 80 major combatants in 20, 30 years from now?
Delete(More pessimistically, will we even have a navy anymore in that time frame? The World Wonders.)
Blogger seems to have eaten my post so I'll try again:
Delete- Our major combatants (CG/DDG) are limited and only in sufficient numbers today for 2 full task forces of escorts, centered around carrier task forces.
- Given the readiness issues plaguing the Navy, it is questionable if we can get sufficient numbers of warships to the field today - let alone in 20, 30 years from now, as ships get more expensive and building runs continue to shrink.
- if the limited CGs and DDGs are serving as FCTF escorts, this means either:
= Frigate SAGs led by a single CG/DDG for air cover (i.e. the Japanese/Korean method) - this is not viable in the face of saturation attacks.
= DDG SAGs, which dilutes the escorts available for carrier task force.
= Pure frigate SAGs, accepting that these ships are expendable, and are being expended to achieve an objective.
In the worst case, if our ship numbers shrink, we might have to choose between assigning our CGs and DDGs to either be FCTF escorts, OR SAGs on independant actions, which will limit us operationally either way.
But well, sometimes you have to roll the hard six. This is one of those times.
Admittedly, this would be where stealth measures would serve to mitigate a certain level of risk towards ships that are not intended to perform AAW.
"Blogger seems to have eaten my post"
DeleteYour comment went to the blog spam folder which is why it didn't appear. This is a sporadic, on-going problem which has no apparent cause and no fix. I check the spam folder several times per day and immediately clear any comments for publication. In the future, if a comment seems to disappear, just wait a short while and it should show up as I check and clear the folder.
Out of the hundreds of comments, only a couple percent wind up inadvertently in spam but I know it's frustrating for writers. My apologies and I wish there was something I could do about it.
This is an older study that looked at making a stealthy lower cost destroyer that went nowhere. Interesting design iteration.
ReplyDeleteI would like to see someone build it.
DD21a
the final design had pod propulsion and the prime movers outside the hull in the hanger.
DeleteMLW
The study really looked at trying to retain capability with minimal cost
DeleteWhy don't you analyze the design and tell us what's good and bad about it?
DeleteI'll try. The paper is about a method of design iterations that use a computer program the navy used back in 1993 to evaluate ships using a set of components in the design library.
DeleteThe baseline design was a conventional destroyer similar to a Burke with multiple (4)propulsion turbines and multiple turbine generators.
The final design with a transom flap had the following features
-12000 NM range
-lower radar signature (tumble home hull)
-lower infra red signature (exhaust outlet is similar to Visby's"
- podded propulsion that didn't cavitate until 25 knots.
-podded propulsion designed to be removed/replaced at pier side
-better maneuverability
-modular power units(2) with energy storage that allowed for more efficient fuel use and reduced the number of turbines needed.
- same weapons load as baseline destroyer
the major detraction to the paper is the experience with the WR-21 turbine that was used in the study. The WR-21 turbine has had a poor track record installed in the type 45 destroyer.
MLW
The design placed the prime movers outside of the hull which removes the ducting for the turbines and gives more volume in the hull for the crew. I don't know if that is a good or bad thing.
DeleteMLW
mounted at deck level you keep the center of gravity lower than at 01 or 02 level as they proposed. build a low profile superstructure around the power plants.
Delete"I'll try. The paper is about a method of design iterations"
DeleteThanks for summary! I have so many documents to read each day that this kind of summary really helps.
It sounds as if the study focused mainly on power aspects? I like the idea of propulsion pods. They have several obvious advantages but I'd like to see the Navy evaluate them for combat duty. I did a post on pods. See, "Pod Propulsion"
Perhaps i have wrong impression but where is the ONR budget/programs for developing low observable hulls eg Wakes, in Europe developing the simple Hullvane, main driver to reduce fuel consumption but major side effect is it reduces the ships wake, if so why is ONR not looking into to see if effective/practical.
ReplyDeletehttps://www.youtube.com/watch?v=4Npm5FXnOLE&ab_channel=HullVanebv
Propulsion/noise, what surprised me is with the Damen design of the new German F126 frigate, have opted for large main diesels over GT's, the diesels come with much better fuel consumption, a big plus for operating in Pacific, lower infrared signatures and equipped with a high-displacement, soft-resilient mounting system to minimise shock and noise and expect lower cost than GT's. Another intriguing choice was a DC grid not AC, allows the diesel generators to operate at optimal variable speeds to match actual power required (with the Burke the Navy requires two of its AG9140 GTGs to be operating all the time, even if the power is not required so if one fails for any reason instant power available to avoid electric power outages as it takes approx a minute to synchronize a GTG with AC grid whereas near instantaneous with DC grid). Other pluses with DC bus it also saves weight/cost/space as it eliminates the main switchboards and drive transformers.
"Hullvane"
DeleteThe Navy has investigated and installed a similar system on many ships. I haven't heard a formal name for it so I just refer to it as a stern flap. It's readily visible in any drydock or closeup stern photos. As the name suggests, it's a flap installed at the stern, just at or below the surface of the water. It is claimed to produce power savings, fuel efficiency, greater range, etc.
Looks like Congress agrees with ComNavOps that there is a problem in naval procurement. This story is about how the last National Defense Authorization includes a "National Commission on the Future of the Navy" consisting of eight (unknown) advisors. The driver is that "the Defense Department and the Navy have lost credibility in force planning and acquisition." Not sure if this will help, but at least more people are becoming aware of the problem.
ReplyDeletehttps://www.defensenews.com/opinion/commentary/2023/01/17/how-a-new-commission-will-fix-disputes-over-us-navys-force-structure/
" at least more people are becoming aware of the problem."
DeleteSpot on, sir! That's what we're striving for: awareness, followed by eventual action.
Good observation!
"For example, an AAW escort has no need for a helo which instantly reduces the ship’s size by a third – a nice chunk of ‘instant stealth’!"
ReplyDeleteIsn't there a finess ratio (length/beam) to consider? Most warships have a finess ratio in the 8-10 range. Reducing a ship's by a third is going to reduce its beam which will affect, among other things, how many weapons it could carry.
Of course. One wouldn't just chop a third of the ship off and slap a stern on it. You'd redesign and reproportion the ship appropriately.
DeleteAs far as weapons, you make the ship whatever size it needs to be to fit all the weapons it needs for its primary function.
Without a helo deck your ship becomes logistically unsupportable inside of a week.
ReplyDeleteAnd yet we managed to logistically support 6000 ships in WWII without helos. How do you explain that?
DeleteWe had a lot more logistics ships for one thing. We also had ships that by and large were not reliant on complex electronics (that require constant CASREPS).
Delete"We had a lot more logistics ships for one thing."
DeleteTrue. However, today we aren't supporting 6000 ships. We're supporting 280. How many logistics ships do we need?
"We also had ships that by and large were not reliant on complex electronics"
Instead, they were reliant on mechanical devices, fuses, vacuum tubes, pumps, valves, etc. that constantly broke or were damaged in combat and yet we managed to repair or replace them and keep the ships running.
If a piece of gear (electronic or mechanical) has a part that is known to fail then we should be stocking replacement parts on board the ship, in the short term, training sailors to repair the items, in the medium term, and redesigning the equipment so that it doesn't fail, in the long term. Instead, we've abandoned the concept of on board repair in favor of the illusion of shore side maintenance savings. We've abandoned ship board fabrication shops. We've abandoned sufficient manning to conduct maintenance and repairs.
Helos are neither the problem nor the solution.
Hmm. What's that saying about amateurs talk tactics and professionals talk logistics? :)
DeleteAccording to Naval Vessel Register
8/14/45: the US Navy had 6,768 active ships: 833 surface warships (frigates through carriers), 2,547 amphibs, 1,790 patrol and mine warfare ships, 232 submarines and 1,267 auxiliaries. So the proportion of auxiliaries to warships then was 1,267/6,768 18.7%
1/18/23: the US Navy has 293 active vessels of which 29 are combat logistics force. 29/293 = 9.8% So we've probably got about half the numbers we need. And that's conservative since the Navy is a lot more globally dispersed and has a lot less bases than in 1945.
That's why helicopters are important for logistics. (Also ASW, VBSS, etc.) The alternative is to buy and maintain tons more CLF ships. Note that the first flight of BURKEs were built with decks and no hangars to maximize stealth as you suggest. I was told they rapidly saw the folly in that approach when AEGIS stuff started breaking!
As for extra spares. Nice idea but hugely impractical given reliability and failure rates. Stockpiling enough spares would make the ship the size of a battleship which defeats the stealth idea you are pushing. Making equipment more reliable is also great but there's a (very big) cost to that too. There are no free lunches in logistics.
" I was told they rapidly saw the folly in that approach when AEGIS stuff started breaking!"
DeleteEither someone is feeding you nonsense or you're drawing conclusions of your own that are unsupported. The Flt I Burkes had both a forward VERTREP area laid out on the deck and a full flight deck aft. Thus, they had plenty of capacity to receive spare electrical components via helo. Wherever those components were coming from would have their own helo, if needed.
The 'folly' of the missing hangar/helo was in ASW not electrical component replacement.
"Stockpiling enough spares would make the ship the size of a battleship"
If a ship is suffering breakdowns sufficient to require spares storage making it the size of a battleship, the ship and its components desperately need to be replaced with components that have a mean time between failures of greater than a couple of minutes. Again, someone is feeding you nonsense or you're engaging in hyperbole in attempt to make an unsupported point.
We supported a global navy of over 6000 ships. Today, we have an average of around 30 deployed ships on any given day. The Navy would like to get that number up to around 50 but is so far failing. Our actual logistic support requirement is for around 30 ships.
Helos are neither the problem nor the solution. We've grown lazy and have come to believe that the convenience of a helo has become mandatory rather than an unnecessary luxury.
"Today, we have an average of around 30 deployed ships on any given day. The Navy would like to get that number up to around 50 but is so far failing..."
DeleteThe USNI News Navy tracker as of Jan 17, 2023 showed 102 ships deployed (67 USN, 35, USNS) of which 56 are underway (41 deployed, 15 local). Not sure what the average is but seems a bit higher than what you claim.
https://news.usni.org/2023/01/17/usni-news-fleet-and-marine-tracker-jan-17-2023
Regardless, we were comparing the needs of a 6,000 ship navy to a 280 ship navy. Were all 6,000 of those ships deployed? Seems unlikely. I will also note that we don't (or shouldn't!) buy our logistics capacity solely to support forward presence needs.
You don't seem to understand how afloat logistics work. Not an insult. It's complicated. In general, CLF ships offload to the carrier and the accompanying small boys treat the carrier as the storefront. Not having your own helo is actually a huge disadvantage. The Flight I DDGs were generally not looked upon favorably by our CSG CDR for that reason. I can only imagine the difficulties that DDGs are doing more independent deployments, although I would think most of Flight Is will retire in next 5-10 years which solves that mistake.
A warship that cannot embark a helo and cannot do ASW as you propose is pretty worthless unless paired with one that can which pretty much defeats the "stealthiness". History has shown that we never quite know where all the submarines are even when we think the battle is won.
https://en.wikipedia.org/wiki/USS_Eagle_56
I follow the USNI fleet tracker and the long term average deployed ships is around 30. However, even using a figure of 41 or even 56 compared to a logistics fleet of 29 says we absolutely don't need helos to keep Burkes from drifting helplessly in the sea after a week, as you claim will happen.
DeleteYou clearly don't understand how at-sea resupply works. There is no global fleet of helos waiting to make daily deliveries to each ship of the hundreds of parts that failed that day. Resupply is handled by ships that can directly transfer large quantities of material. Helos may be used BY THE RESUPPLY SHIP as a matter of convenience but they are not necessary. Once the resupply ship finishes and leaves, it doesn't come back every couple of days.
You also seem to have an absolutely ridiculous notion of how often/many failures occur. A ship can easily store all the reasonably anticipated spares without becoming the size of a battleship. Until the LCS, ships have always carried all the spares they need and it has not affected their size to any appreciable extent.
We conducted resupply routinely in WWII without a single helo. Amazing, isn't it?
Regarding logistics support, helos are an unnecessary luxury not a necessity.
question - if our electronics are going to break when we take missile hits, and we need spares to fix them.... wouldn't that mean that our spares are also at risk of getting broken in the same shockwaves that our ships are taking? They're colocated on the same ship, afterall.
DeleteI don't see how spares in a box are going survive impacts that are gonna break computers in racks.
"wouldn't that mean that our spares are also at risk of getting broken in the same shockwaves that our ships are taking?"
DeleteYou may not be understanding the mechanism of electronic shock damage. While individual components certainly can break, it's more an issue of system level failure. For example, the Aegis radar arrays require extremely exact alignment. When the Port Royal drifted aground (about as far from a combat explosive shock as possible!) it knocked the arrays out of alignment and the Navy was unable to re-align them to a satisfactory degree and wound up recommending the ship be retired. Similarly, the VLS tubes apparently have very precise alignment requirements and were also knocked out of alignment.
Missiles have lots of circuit boards and electronics and the shock of catapults and landings wreaks havoc on them by knocking individual chips, resistors, etc. loose. Explosions would cause similar damage to ship's computers and electronics as well as physical destruction.
Spare boards and components would be stored throughout the ship and would be at no greater risk of destruction than any other piece of equipment in the ship. Since the spares are not installed in anything, there's nothing to come loose and, being cushioned in original packing, they'd have a much better chance of surviving shocks.
Hopefully, this gives you a better understanding of the issue.