'Sunburn' vs. 'Sea Whiz' (Are US Carrier Groups Outmatched?)

USS America (Ret.) CVBG

Nothing exemplifies America's ability to intercede in an international crisis and project military force anywhere in the world at a moment's notice more than an United States Aircraft Carrier Battle Group (CVBG). While our strategic nuclear missile arsenal might be considered to be the ultimate weapon by which we may dominate world affairs, it is the carrier group that has been the practical dominant element since World War II. The workhorse of military might bridging the gap between tactical and strategic military objectives with agility, adaptability, and overwhelming firepower.  But is this force something that we as Americans have come to take for granted? Is this illusion of invincibility dangerous? Is there a legitimate threat in the world today that might have the ability to overwhelm a CVBG and ultimately sink an aircraft carrier, that awesome symbol of American military, economic, and political superiority in the world?

If so, it is most likely be the "Sunburn" family of anti-ship missiles first developed by the Soviet Union, still in production and continued development today in Russia. Western intelligence on these missile systems, particularly later models, is believed to be dangerously limited. At the very least, this is probably the front-line of cat-and-mouse naval intelligence operations for more than two decades now. Versions have been sold to China, Iran, Syria, Vietnam, India and Indonesia, but western nations have been barred from purchasing production models. Sunburn is the NATO call-sign for SS-N-22 designation. What we did not learn until after the collapse of the Soviet Union though, is that there were actually two different projectiles being deployed in identical-looking launch units, which confused the intelligence on the weapon(s). One was the P-80 Zubr rocket. The other, a far more lethal surface-skimming, rocket-ramjet driven, supersonic mach-3 nightmare to western sailors.

SS-N-22 Sunburn anti-ship cruise-missile

A wide number of letter/number designated variants of the MKB Raduga manufactured missiles can be deployed from ships, submarines, jet-fighter aircraft, and mobile land-based launchers. Known as the Moskit (Mosquito) by the Russians, it can be armed with a 700-pound (300-kilo) conventional warhead, or a thermonuclear warhead with an estimated yield of 120-200 kilotons. In a high-altitude attack trajectory, the weapon is .5 to nearly 1 mach-speed faster, but when deployed in sea-skimming mode it is unlikely to be detected until literally the last minute, at most, before impact on target giving defense systems precious few seconds to counter the supersonic threat once it appears in line of sight coming over the horizon. Even if detected in time, the unit can be programmed to execute last-minute radical maneuvers in order to counter defensive projectiles emitted from the target. In essence, it makes counter-countermeasures maneuvers to snake it's way into the hull of its victim.

The Sunburn is designed to counter the automated defenses of the Aegis command and control system, at a comparatively very low cost. Named for the shield of Greek mythological hero Athena, the fleet defense system integrates detection, information  and weapon systems. Aegis platforms are even integrated into the larger Aegis Ballistic Missile Defense System of the United States Missile Defense Agency. The system has en proved capable of shooting down satellites, on the far end of it's capabilities. At the opposite end, is the close-quarters last line of defense against threats to the Aegis-equipped ship whichis charged with protecting the flag-ship of a Surface Action Group (SAG) or the aircraft carrier(s) at the core of a CVBG. The Phalanx CIWS, or "Sea Whizz," is the tip of that spear, in which a few seconds will determine the fate of hundreds, if not thousands of lives.




Although the Sea Whiz operates in concert with the other components of the Aegis command and control system, it also has it's own impressive internal capabilities that will let it operate with a a very high degree of autonomy as well. All that it requires externally is power and cooling water, but is equipped with it's own radar and target acquisition system along with other sub-systems. Not only does this give the Phalanx adaptability to other platforms and applications such as fixed placements around high value targets and even land-mobile transports as we saw in the video above, but it also gives it a greater probability of continuing to operate even after a ship has been hit. Releasing a blistering fire-worm of 20-mm depleted uranium at a rate of 4500 rounds-per-minute through it's 6-barreled M-61 Vulcan cannon, it certainly offers a formidable response to interlopers.

It is not equipped with an IFF system which explicitly identify a contact as "friend" or "foe," but variable parameters can be set in order for the system to make that determination based upon other criteria. The computer discards out-bound targets but will contemplate whether a contact's trajectory and velocity in relation to the ship might allow it to perform an offensive maneuver. The operator can program a response envelope in relation to speed and angle that the weapon should either ignore or consider hostile. A slow moving airplane might not be considered a threat, but a faster moving aerial object that might be a missile and should therefore be considered a threat ny the system. Or for another example, a surface contact traveling at 15 knots might not be considered a threat, but if it suddenly turns to directly intersect, it should be considered a threat regardless of speed.

These settings must fall within the maximum performance parameters of the system itself though, of course. It cannot engage a target traveling at a higher rate of speed than the computer can calculate or that the weapon itself can physically turn on target. What the maximum velocity of a target might need to be in order exceed what the Sea Whiz can operate against is most likely classified, and no such data is apparent in recently viewed sources, but we have now obviously shown that the system does indeed have an inherent weakness. While the weapon is sure to make mineral deposits out of things like inbound drones, small boats, airplanes and even many classes of anti-ship missiles, supersonic anti-ship missiles strain the system closer to the maximum performance specifications of the system's various components. Indeed it is possible that the Sea Whiz may not be able to engage the Sunburn with a very high rate of success at all.

There are no documented engagements to date which involved the Sunburn, but there is other information from which we can draw inferences on how well a ship might fare against an assault by a platform utilizing the dangerous anti-ship missiles. The Exocet is a French manufactured sub-sonic anti-ship missile that also travels at low-altitude in order to avoid radar detection, but at less than half the speed of the Sunburn. Nonetheless, this weapon has been deployed in live-fire engagements with some success. In 1983, the Falklands War unfolded between Britain and Argentina. The British guided-missile destroyer HMS Sheffield was sent to the bottom after being struck by an Exocet that had been launched by an Argentinian Navy Super Etendard strike-fighter. A second Exocet missed and fell into the sea. Surprisingly, it was later determined that the warhead of the anti-ship missile failed to explode. The damage was done as the result of kinetic energy and secondary fires.

From this engagement we learn that sea-skimming missiles do indeed pose a serious threat warships for one. Of course, this engagement happened nearly 30 years ago now and new technologies are in use today. Nonetheless, a ship of the Royal Navy might be assumed to be equipped with the best equipment of the time. They failed to even detect the missile in time, much less deploy offensive countermeasures. What we really take from this though, is the devastating affect kinetic energy can have. Considering the larger size and far greater speed, one could expect far more damage coming from the Sunburn through kinetic energy alone, and then of course the successful detonation of the munition itself.

Kinetic energy poses another problem as well. The effective range of the Sea Whiz is about 2 miles. Which means that even if it successfully interdicts inbound traffic, there is a risk that debris will still cause damage. A super-fast Sunburn will only make it that much closer to the ship carrying that much more energy even without the explosive intact after being struck by the Phalanx. In 1983, the USS Antrim was conducting a live-fire exercise which provides us another good example of the affect of kinetic energy. The Phalanx Sea Whiz hit the drone, but the debris skipped across the water and slammed into the ship. The drone's fuel set fire to the ship and a civilian contractor was killed.

Now we also have another example of the sort of damage that the far less capable Exocet can do, and this time directly against an American warship. In 1987 the USS Stark was operating in the Persian Gulf. She was approached by an Iraqi Mirage F1 jet fighter that came within about 15 nautical-miles of the ship and was warned away. The ship's systems did not detect that the plane had in fact launched a pair of Exocet anti-ship missiles. A lookout spotted the inbound tracks visually, but it was not in time for the ship to fire a single round or deploy any other countermeasures. The first missile that struck failed to detonate, but still ripped through the hull. The second impact resulted in an enormous blast killing 37 sailors while another 21 were injured. Despite a serious list initially, the Stark made it back to her home-port under her own power after some assistance and hasty repairs. Though no one would want to call what happened to the Stark lucky, it certainly could have been worse had that second missile detonated, or perhaps if the two had not struck in nearly the same point on the ship. Regardless, we see here a failure against a popular but less capable anti-ship missile which seems to point to the likelihood that the Sunburn would only be that much more effective in an engagement.

To be accurate though in this match-up analyses, the failure does not appear to rest entirely with the Sea Whiz. Several of the ship's top commanders faced court-martial and were forced into retirement after the event. Had the ship been cruising at a higher state of readiness, would the Sea Whiz have knocked down the Exocets? Possible, even likely that it would have gotten at least one of them. But now this also brings up another inherent weakness with the system.

Although a ship may be equipped with more than one Phalanx mount, each one can only engage a single target at any given moment. It can track multiple targets, but cannot engage them simultaneously, again making it more likely that faster inbound traffic will make it through the defenses before the Sea Whiz has the chance to respond, if there are multiple targets. A saturation raid by multiple ASM's will overwhelm the Phalanx's response capabilities, and again especially with higher velocity inbound traffic.

Let's break this down mathematically. We will still have to shoot from the hip here so to speak though, considering that we do not know the exact capabilities of the weapons systems. The effective range of the Sea Whiz is a little over two miles with a muzzle velocity of 3,600 feet-per-second. This means that it takes about three seconds for the bullets to reach the effective interdiction point against the Sunburn. At mach 2.2, the Sunburn is traveling at a little under 2500 fps. Assuming that the Sunburn is detected at 12 miles out with an approximate half-mile per-second rate of closure, that gives the Sea Whiz no more than 24 seconds to process data, calculate response, swivel in order to position the barrel accurately and fire. Keep in mind too that we must now also subtract another three seconds for the rounds to reach the 2-mile effective range of the weapon. Interdiction at a greater distance will likely cost in ammo expenditure with loss of accuracy and increasing bullet-velocity decay. This of course means that fewer ASM's would be necessary to saturate the defense as the Sea Whiz will no longer have the necessary ammunition to respond.

This saturation effect could be even more pronounced with the next generation of CIWS systems as well. The Raytheon SeaRAM essentially replaces the 20mm six-barreled whirling cannon, with an 11-shot Rolling Airframe Missile launcher, leaving the rest of the CIWS unit intact. So there is no upgrade to the system itself, only to the munition, which Raytheon promises will deliver increased range, accuracy, and maneuverability.

When we look at increased range, we still have to consider the limitation of the CIWS system itself. It does not have over-the-horizon detection capability, but the anti-missile missile will not have to wait for the inbound traffic to come closer into the 2-mile effective firing range of the Vulcan cannon either, effectively increasing the standoff range of the system overall. The accuracy and maneuverability will have to make up for the fact that the launcher only houses 11 missiles. It is likely that most of the 11 missiles will hit their mark if the accuracy and maneuverability are delivered as promised, but there is no guarantee that they will in fact effectively counter the evasion techniques of the Sunburn missile, or other hostile inbound traffic. There is no immediate reload either, leaving the ship defenseless once the ammunition has been expended. This means each missile must hit their mark and that launching a second missile as insurance will be out of the question, with the need to preserve ammo a paramount concern for the operator. Do you want to bet that a single shot will indeed be accurate enough to counter the Sunburn's avoidance techniques? Or do you fire another missile at it just in case, risking that you will have no ammo left should you become saturated by inbound targets?

It is also important to note that this faster, more accurate anti-missile defense system is still under development and that the first one was only deployed in 2008, aboard the USS Independence. So most ships in the US Navy are still operating with the 20mm canon CIWS system. At the end of the day, are either system really up to the task of countering the threat posed by the Sunburn family of anti-ship missiles? It is my opinion that it is a dodgy proposition at best, and that nations such as Iran do indeed pose a very serious threat to US Naval forces.







Here are links to more information:


http://navlog.org/sea_ram.html

http://www.freerepublic.com/focus/f-news/966345/posts

http://www.softwar.net/3m82.html

http://en.wikipedia.org/wiki/P-270_Moskit

http://en.wikipedia.org/wiki/SS-N-22

http://www.globalsecurity.org/military/world/russia/moskit.htm

http://www.ausairpower.net/APA-Regional-PGM.html#mozTocId998316

http://www.informationclearinghouse.info/article7147.htm

http://www.nogw.com/ruweapons.html

http://abundanthope.net/pages/True_US_History_108/Russian-Super-Sunburn-SS-N-26-ONYX-Missiles-Make-US-Navy-Obsolete-US-Attack-on-Iran-Suicidal.shtml