Submarine Anti-Air Capability

The Navy is looking to develop an anti-air missile for use in submarines (and surface ships).
 

The U.S. Navy has shared details about its vision for a new family of modular surface-to-air missiles that is expected to include a version that will arm future variants of the Virginia class submarine.[1]

The War Zone website has an interesting article about this with a decent discussion of the weapon and some of the benefits and drawbacks.[1]  The weapon is presented as a modular miracle that can include hypersonic versions, various ranges, and various packaging options and will be capable of destroying everything that flies, from drones to hypersonic ballistic missiles.  Truly a miracle weapon … as all new weapons are.
 
Will this be a common sense, evolutionary development or enhancement of an existing, proven weapon?  No!  It will be revolutionary!
 

The United States Navy (USN) is seeking a new, modular interceptor to serve as the basis for the Naval Modular Missile (NMM) program, a next-generation initiative designed to revolutionize surface naval capabilities … [1]

How many weapon systems just over the last few years have promised to revolutionize naval warfare?  Dozens!
 
How many weapon systems have actually revolutionized naval warfare?  None!
 
And yet we keep making the claim.  Hmm …
 
But, let’s get back to the specifics on this particular system.
 
The article describes the potential use by submarines to shoot down ballistic missiles in the launch/boost stage, at any point in flight, or for terminal defense as well as for use in providing AAW protection for carriers and, of course, for shooting down local ASW helos and patrol planes. 
 
To be fair, the article does briefly mention a few potential issues with this and we can think of others.
 
A submarine operating tactically close enough to a surface group to provide anti-air protection is subject to the ages old problem of blue-on-blue friendly fire.  No surface ship is going to allow an unknown submarine to operate near it on the possibility that it might be friendly.  Submarines are a sink-on-sight target, no questions asked.  It is the responsibility of the submarine to not operate near any other friendly submarine or ship because of the inability to distinguish friend from foe.
 
Every subsurface to air missile cuts into the very limited missile inventory of the submarine and reduces its offensive capability which is, of course, the submarine’s entire reason for being.  A submarine’s need for subsurface to air (SSAM) capability would be extremely rare.  Let’s face it, if you’re a submarine captain and you find you need SSAM very often then you’re not doing your job correctly!
 
A submerged missile launch requires the submarine to come to a shallow depth – generally the opposite of what a submarine wants to do in combat.
 
A missile launch creates a great deal of noise, heat, and visual display.  In other words, it likely gives away the submarine’s position.
 
Most obviously, the major issue is targeting.  A submerged submarine has extremely limited air search capabilities so where is the targeting for all these wondrous anti-air scenarios coming from?  Even the local anti-air scenario presents difficulties in targeting.  You may be able to hear a helo and have a general direction but that’s not enough for an anti-air launch.  Surface ships with exact radar pictures have a hard time establishing exact targeting for SAMs and a submerged submarine has far less chance.  Simply launching a SSAM and hoping it can find a target somewhere in the hemisphere around the sub is a recipe for wasting missiles. 
 
As far as receiving targeting from a remote platform, it is challenging, at best, to send real time targeting data to a submerged submarine without unacceptable risk to the submarine.  This also ignores the practical question of what platform could survive long enough to produce targeting data deep inside enemy waters.
 
 
Discussion
 
The SSAM inventory on a submarine would be very small unless someone wanted to abandon the submarine’s primary mission and instead perform AAW.  Is a very small inventory, meaning a very small AAW contribution, worth risking the submarine and compromising its main role?  I think not.  This smacks of yet another example of the Navy’s misguided attempts to make every platform a single-handed war winner.  We have ships designed specifically for the AAW role.  Let them do their job and let submarines do theirs which is offensive operations.  Do we want to risk (due to friendly or unfriendly fire) a several billion dollar sub trying to shoot down a million dollar missile when there are surface ships (Aegis) designed and suited exactly for that task?
 
Some might say that a submarine could be the unseen, forward AAW “shooter” with targeting provided by some other platform in a scenario analogous to the unmanned USV “shooter” vessel being placed far in front of a surface group and cued by a Burke or patrol plane .  Of course, that ignores the problem of how to communicate real time targeting data to a far distant, submerged submarine (as well as the blue-on-blue issue).  As far as I know, that’s a practical impossibility.
 
That said, it might be worthwhile having a half dozen or so SSAMs for the local defense scenario (anti-ASW helo) if the targeting issue can be solved.
 
There’s a reason why there has not been wide spread adoption of this technology among world navies.
 
 
 
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[1]The War Zone website, “U.S. Navy Is Seeking A Submarine Launched Anti-Air Missile”, Joseph Trevithick, 31-Jul-2026,
https://www.twz.com/sea/u-s-navy-is-seeking-a-submarine-launched-anti-air-missile

More Defensive Missile Data

I’ve repeatedly stated that ship anti-air / anti-missile defenses will perform far worse than the Navy believes.  I’ve backed that statement up with all the available historical data which, to be fair, is not a lot.  However, what data exists unequivocally proves that defensive surface to air missiles (SAM) have a probability of kill (pK) in the range of 1%-25% with the vast majority falling in the 1%-10% or so.  Despite this, there is a group of observers/commenters who have a vastly inflated confidence in SAM systems that is based on nothing but the same promise of improved technology that accompanies every new SAM system and that, ultimately, fails to deliver.  Well, here’s a new data point for Russian S-300 system performance against Israeli aircraft:

Syrian air defense forces having launched more than 1,000 surface-air missiles to try and foil the repeated Israeli attacks. They’ve had little effect so far. (1)

While this does not provide exact numbers, the trend seems clear.  I’ve heard of no reports of downed Israeli aircraft nor any credible claims of downings by Syria.  Thus, the Russian S-300 system would seem to have a pK of, essentially, zero.

S-300 - Ineffective?

I know exactly what some of you are going to say.  You’re going to wave away the failings of this system and point to the wondrous S-400 system.  Well, I’ll remind you that the S-300 once got the same rave reviews that the S-400 gets today.  Dr. Carlo Kopp, the renowned author, had this to say about the S-300 system in 2006.

The S-300 SAM systems remain one of the most lethal, if not the most lethal, all altitude area defence SAM systems in service … (2)

This is yet another data ‘point’ that proves that SAM success rates are quite poor across all eras and all systems.  Despite this body of evidence, the US firmly believes that its missile systems are extremely effective, to the point that we don’t even mount close in weapon systems on the Zumwalts.  We desperately need to put our defensive missile systems through real, live fire weapon trials on sacrificial barges and find out what they can, or cannot, do.

__________________________________

(1)Breaking Defense website, “Unanswered Israeli Air Strikes Against Syria Raise S-400 Questions ”, Arie Egozi, 9-Jun-2020,

https://breakingdefense.com/2020/06/unanswered-israeli-air-strikes-against-syria-raise-s-400-questions/

(2)Dr. Carlo Kopp, 25-Feb-2006,

https://web.archive.org/web/20110928142727/http://www.strategycenter.net/research/pubID.93/pub_detail.asp

Stand And Fight

There is an old adage that governs the ultimate rationale for naval forces: 

The seat of purpose is on the land.

Sooner or later, a naval force must engage land forces.  That engagement can take the form of direct strikes from missiles or carrier aircraft or can be amphibious assaults to get land forces ashore.  Either way, it means that a naval force must, eventually, approach land.  This is where the Navy/Marine’s idiotic doctrine of conducting an amphibious assault from 25-100+ miles at sea falls apart.  If you won’t approach land, you can’t influence events on land which is where ultimate purpose resides.

Yes, there are other ways to influence events on land.  A blockade, for example, can influence events on land.  For countries that have an alternate, land-only means of engaging an enemy, the naval forces can get by with just playing a minor, supporting role like a blockade.  The Union Navy did this during the American Civil War by imposing a blockade on the South.  However, for a country that has no direct land contact with an enemy, there is only one way to get troops to the enemy and that is by sea.  Yes, air transport can move a few troops but only sealift can move the massive quantities of men, weapons, ammunition, and supplies that are needed for sustained combat.

Acknowledging, then, the necessity to eventually approach an enemy’s land, the naval force structure planner must ask what forces, weapons, and tactics will allow a reasonable chance of survival while conducting near-land operations.  Assessing survival equipment needs starts by identifying the major threats.

The biggest threats to naval forces wishing to operate near land are,

• Mines
• Submarines
• Anti-ship missiles (ASM)

Ironic and troubling, isn’t it, that the US Navy has no effective combat mine countermeasures capability, no effective, dedicated surface ship anti-submarine (ASW) vessels, and limited and non-survivable aerial ASW capability?  The Navy is ill-prepared to deal with two of the three major near-land threats.  At least the anti-ship missile threat is manageable with our large fleet of Aegis equipped Burke class ships.

It’s further ironic and baffling that the Navy’s stated reason for doctrinally refusing to approach land is the threat of land based ASM’s, the one threat for which we are prepared!  Let’s set aside the mine and submarine threats and examine the ASM threat a bit closer.

The Navy has spent billions of dollars on its Aegis capability.  The system was designed and intended to counter saturation swarms of Soviet anti-ship cruise missiles launched from entire regiments of long range bombers.  Aegis is designed to handle large numbers of targets simultaneously and can do so in a completely automatic mode – and, in fact, is more efficient and effective in that mode.

With all that capability in mind, one has to wonder why the threat of a relatively few isolated, land based cruise missiles so terrifies the US Navy?  Either they know that Aegis is an utter failure or they’ve become so risk averse that they can’t imagine actually standing and fighting and possibly losing a ship.  I tend to believe it’s the latter.  I’ve seen nothing to indicate that Aegis is a failure but, to be fair, there is little actual data to indicate that Aegis is a success!  Still, I’ll assume it’s capable until I see data indicating otherwise.

So, if Aegis is capable of handling the ASM threat, then the Navy is just too scared and too risk averse to stand in harm’s way and execute their function.

Let’s look at the arithmetic of the situation.  For a high subsonic cruise missile, like the Chinese C-802, the missile speed is around 680 mile per hour and it cruises at an altitude of 10-20 m which decreases to 3-5 m in the terminal phase.  The Navy is scared to stand near shore and, apparently, feels that the extra 25-50 miles will enable them to more effectively engage such an anti-ship cruise missile.  Will it, though?

Here’s the raw reaction times for various distances.

10 miles = 0.9 minutes

25 miles = 2.2 minutes

50 miles = 4.4 minutes

Unless an ASM is sited nearly on the beach – in which case it would, presumably, have been spotted, targeted, and destroyed as part of the assault preparations – the launch site will likely be 10-100+ miles away from the assault location.

At the low end of that range, 10 miles, and assuming the defending ship is beached so that there is no extra range added, 10 miles provides around 0.9 minutes of reaction/defense time.  In the world of computers and a fully automatic Aegis system, 0.9 minutes is an eternity!  Longer distances simply provide even longer reaction/defense times.

Stand and Fight!

In any realistic scenario, say with the Navy ships about 5 miles offshore and the enemy anti-ship missile launchers around 10-100+ miles away, the reaction time is more than adequate.

There’s no question that longer distance translates to more time to defend.  However, a couple of minutes is more than enough time.  If you can’t shoot down an incoming missile in a couple of minutes of engagement time, a few more minutes isn’t likely to produce a positive result.

Ultimately, the risk of standing in close and fighting must be balanced against the accomplishment of the mission.  It does no good to remain safe, far out at sea, but unable to accomplish the mission.  If the mission is worthwhile, then the risk is acceptable.  The Navy’s defensive systems were built for this.  Trust them to do their job.  Stand and fight.

AAW - Hard or Soft Kill?

The Navy has been firmly committed to the hard kill option of the Aegis/Standard Anti-Air Warfare (AAW) system as the main line of defense against attacking planes and missiles.  Additional hard kill elements include a variety of shorter range missiles and guns such as RAM, SeaRAM, CIWS, and various rapid firing guns in the 3”-5” range.  A secondary, soft kill system of decoys and electronic countermeasures (ECM) is also used but has not been developed and upgraded with the same attention and priority as Aegis and the various hard kill components.  For example, the Navy’s main ECM system, the SLQ-32, is well behind the times, bordering on obsolete, and the Navy is only just now beginning to look at upgrading it.



SLQ-32 - Not Enough Love?



We see, then, that the Navy uses both hard and soft kill systems for AAW with an overriding emphasis on hard kill.  Is this wise?  What is the success rate of each?  Which is more likely to be successful against future threats?  Is the Navy pursuing the best course in AAW development?

We’ve already discussed the historical data regarding anti-ship missile attacks on passively defended (soft kill) vessels.  The data shows defensive success rates of around 80%.



Historically, there have been very few combat AAW missile launches so there is not much of a database to draw conclusions from.  The best data set that I’m aware of is from the Falklands War between Britain and Argentina.  During that conflict, at least 26 Sea Dart missiles were launched.  Wikipedia reports that of 5 missiles launched against helicopters or high flying, relatively slow aircraft, 4 hits were achieved.  By contrast, there were only 2 hits out of 19 launches against low flying aircraft.  The Falklands totals for the Sea Dart, then, were 6 hits out of 26 launches (23% success).  Wikipedia further notes that an unspecified number of launches were made without guidance in an attempt to break up low level attacks as a result of limitations of the missile system.  In addition, the Sea Wolf missile, designed for use against low level targets, achieved 2 kills in 8 launches for a 25% success rate, according to Wikipedia.

Note that the Falklands AAW actions were against planes, mainly, rather than missiles which are a much more difficult target.

To the best of my knowledge, Aegis/Standard has never been fired in combat in the AAW role so there is no direct data to examine.

We’ve also discussed from time to time that Aegis is such a complex system that it has fallen into a fleetwide state of reduced performance and readiness.  The Navy has had to implement special programs in an attempt to bring Aegis back up to standard but the system remains degraded across the fleet.  The complexity of the system largely precludes on-board repairs by the crew and, in fact, makes it virtually impossible for the crew to even spot degraded performance.

What do all of these bits and pieces tell us?

One obvious conclusion is that soft kill methods have a far better performance record than hard kill.  That’s probably not all that surprising given the difficulty of trying to guide an AAW missile on to an incoming, high speed, maneuvering target.  To be fair, that conclusion is drawn with no data input from the Aegis/Standard system.  Will Aegis perform markedly better than Sea Dart?  My guess, based on nothing, is that Aegis will perform better but nowhere near the 80% success rate demonstrated by soft kill systems.

Another point to consider is that any AAW system works best in a fully automatic mode.  Unfortunately, commanders are reluctant to operate that way for fear of unintended mishaps.  Indeed, there have been numerous such incidents.  For example, Sea Sparrow has fired on friendly ships during exercises and CIWS has fired on friendly chaff and helos with each example causing damage and casualties.  Contrast that to soft kill systems operating in automatic mode.  There is no danger.  Soft kill systems can be left on continuously, EMCON considerations not withstanding.

Further, consider the cost of upgrading the capabilities of hard and soft kill systems.  Hard kill systems require software upgrades, which are relatively easy to implement, and hardware (the missiles) upgrades.  The Navy has spent a great deal of money upgrading the Standard missile from Block 1 through the various versions to Block 6.  Soft kill system upgrades, by comparison, are almost exclusively software based, again relatively easy, and the hardware upgrades are far less expensive.  Thus, soft kill systems can be more easily kept up to date and responsive to the ever-changing threats.

Next, consider the real estate required for hard kill and soft kill systems.  Missiles and their launchers require enormous amounts of deck space and internal ship’s volume.   Soft kill hardware requires very little space.  The result is that the smaller the ship, the less hard kill defense capability it has.  To a large extent, soft kill systems are independent of ship size.

Finally, consider the danger that hard kill systems pose to themselves.  The missiles represent a source of internal explosions in the event of a hit on the defending ship.  Soft kill systems present little self-threat.

It’s clear, then, that soft kill systems offer historically superior performance, easier upgrade paths, can be operated more freely, require little space, and present no threat to friendly forces or the defender.  The Navy should be much more focused on soft kill systems than they currently are.

Why, then, is the Navy so focused on hard kills?  Well, for one thing, hard kills are dramatic, definite, and occur at some distance away from the defender.  Soft kills tend not to show a definite result until the missile has approached quite closely and passed the defender.  It’s a lot more reassuring to see missiles disappear at a distance!

What’s the takeaway from this discussion?  I’m not suggesting that the Navy abandon hard kill systems, so half of you can take your itchy fingers off the keyboard where they were preparing to lambaste me.  What I’m suggesting is that soft kill systems are part of a layered AAW defense, along with hard kill systems, but that they should be given much higher priority than they have historically received from the Navy.  As stated, soft kill systems are more effective, cheaper, easier to maintain and upgrade, and safer to operate.  You would think those characteristics would garner far more attention than they do.  C’mon Navy, pay attention to what works even if it isn’t the “sexy” approach.  Soft kill provides more bang for the buck – stop ignoring it!

Helos in the Littorals

The Navy is heavily invested in helicopters from a tactical perspective and few people even pause to consider the limits of their applicability.  Before I go any further, let me state that I, too, see the obvious capabilities of helos.  However, I also see their limitations.  Let’s look at bit closer at the use of helos in a littoral combat zone since helos will be a major, or perhaps the major, weapon system of the LCS. 

SAM - Counter to the Helo?

Regarding the littoral surface warfare scenario (ASuW) and setting aside the question of why we would be there, as discussed in a previous post, I’ve often heard comments that a couple of helos will make short work of a swarm of small craft and, to be fair, in an otherwise permissive environment, that’s probably a true statement.  But think about it …  Is there anything in a littoral zone, and a small craft swarm scenario, that might negate the effectiveness of a helo?  How about man-portable surface-to-air missiles (SAM) like the Stinger or SA-16/18/24 family?  Such missiles have max ranges of around 5 miles and effective ranges of 3-4 miles.  Compare those ranges to the helo’s air-to-ground (AGM) weapons such as Hellfire (5 miles) or Griffon (3 miles).  The opposing ranges basically overlap.  If one’s in range, so is the other.  SAMs can be fired from shore, from hiding in civilian/commercial small craft or, in what should be an obvious tactic, from each boat in a swarm.  The other obvious danger to helos, since we’re going to be fighting in someone else’s littoral zone, is aircraft from nearby airfields.  So, absent a permissive environment, the helo versus swarm is hardly the one-sided affair that many visualize.  Throw in a helo’s limited number of weapons and possibility of mechanical unavailability when needed and the situation is further complicated.  Finally, what about good old fashioned surprise?  If the helo is not in the air when an attack begins, the attack will be over by the time the helo can get airborne.  Helos are not a rapid reaction weapon system.

The above comments also apply in general to littoral ASW.  In the ASW role, helos made their reputation, and deservedly so, during the Cold War sub hunting days in the open ocean which did, indeed, constitute a permissive environment.  In the littoral zone, as described above, the helo is capable of being targeted multiple ways and may well find itself at high risk.  One wonders if this may have been part of the rationale for the original LCS conceptual ASW module consisting of multiple, off-board unmanned underwater and surface vehicles – an attempt to reduce dependence on easily targeted helos.

Helo - Endangered Species?

In summary, the helo is a powerful weapon system but is not the invincible platform that many make it out to be.  The closer helos operate to shore and shallow water with its fleets of small civilian boats, any one of which may harbor a man with a Stinger, the more at risk they are.  For the helo, operating near shore is analogous to the Army fighting in a city.  Snipers can hide anywhere and blend in with the population.  Stingers can be anywhere and can hide amongst the civilian craft.  One has only to look at the Soviet's Afghanistan experience to see how helos fared against Stingers.

The point of this little thought exercise is that we should not become overly dependent on the helo alone.  The LCS (or any ship attempting to fight in the littoral zone) needs a range of options which should include a small ship-launched Griffon/Hellfire-like missile with a range of several miles or more as well as a robust gun arrangement with multiple guns and fields of fire to the stern so that the LCS can use its speed as a tactic to maintain separation.  What’s needed for shallow water ASW is a topic for another day.