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6. Submarine adjuvant vehicles; modified SSN and SSBNs: Submarine-carried ancillary vehicles, including ASDS SEAL-delivery minisubs, unmanned undersea vehicles with mission-reconfigurable sensors, armed unmanned undersea vehicles, and unmanned aerial vehicles launched from submarines, add greatly to the all-weather and littoral advantages of a submarine in both attack and defense, and also significantly enhance that host sub's safety in a wide spectrum of warlike scenarios. The Ocean-Interface Multi-Mission Platform hull module of the USS JIMMY CARTER sets yet another precedent for greater vehicle and weapon capacity and variety, as does the modification of the USS OHIO "boomer" SSBN and three of her sisters into SSGNs (cruise missile and special operations forces platforms).
7. Undersea anti-aircraft weapons: Anti-aircraft weapons launchable from a torpedo tube, such as the Polyphem missile, enable a submarine to destroy enemy aircraft seeking to detect or attack the submarine. This makes the submarine substantially more survivable -- and thus potential loss of stealth is less dangerous to the submarine and her crew.
8. Other active close-in defenses: Several devices are under development to intercept and destroy inbound enemy torpedoes. One such device is an anti-torpedo underwater rocket. Another is an ultra-high-speed dart: A U.S. Navy weapons lab recently announced that it succeeded in firing such a dart underwater at a speed greater than that of sound in water. (The speed of sound in water is approximately five times what it is in air.) One advantage of such a dart is that, by being supersonic in the medium in which the engagement occurs, it cannot be detected acoustically by an inbound torpedo until too late! Yet another means of active defense against torpedoes is a pressure-wave pulse generator array, mounted on the submarine's hull. Such an array would presumably require a large amount of electricity to smash an inbound torpedo with a focused pressure wave; having this power available is one advantage of an all-electric-drive nuclear powered submarine. In the future submarines will be able to actively engage and pulverize a type of weapon -- the ASW torpedo -- which up to now has required more passive defense combined with emergency escape-and-evasion techniques.
To pull together the points established so far, protection of submarines against MAGIC involves a layered defense enabled by network-centric warfare. MAGIC is less threatening if its sensor platforms can be identified and destroyed -- this applies even to space-based platforms, for which anti-satellite weapons (themselves either space-based or ground-based) would be essential. MAGIC is also useless if its data, though accurate, cannot be disseminated to command nodes or to survivable anti-submarine attack platforms having viable weapons. Information warfare assets can be used to target MAGIC's download links. Joint warfighting formations, including active defenses by the submarines themselves and by armed "escort" adjuvant vehicles, can help guarantee that detection does not spell doom.
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Advantage Submarine; the Ocean as Armor
In future naval combat, special properties of the air/sea interface demand full exploitation.
1. Hybrid propulsion, hybrid weapons: Supposing that the seas truly became completely transparent, submarines could restore parity or superiority against surface and airborne platforms if equipped with the proper weapons. Versions of such weapons exist today, or have existed in the recent past but were pulled from operational status because they appeared unneeded in world conditions prevailing at the time. The issue comes down to the speed with which an object can move through the water as opposed to through the atmosphere. Adaptations of SubRoc (a submarine-launched missile that flies through the air and then drops an ASW torpedo or depth charge), and employment of supercavitating underwater rocket weapons (which move at hundreds of knots within a vacuum bubble of their own making), level the playing field between platforms operating in the different mediums of air and seawater. On the one hand, an aircraft (or fixed or mobile littoral land site) can launch a missile armed with a plunging warhead that serves as a depth charge against a submarine, from far away. An aircraft can also cover a large distance rapidly to drop an ASW torpedo -- a self-propelled weapon that attempts to home on the submarine. A surface ship can similarly fire a missile, such as an Updated AsRoc, which delivers an ASW torpedo very rapidly to a distant submarine target. But on the other hand, a submarine's supercavitating undersea weapon might move as fast or faster than an ASW helicopter or maritime patrol aircraft; if such a weapon were equipped somehow with a terminal stage "bouncing betty" anti-aircraft warhead, that plane or helo would be in for a nasty surprise. And a missile launched from a submarine can quickly leave the sea and make great speed through the air -- which was one point of developing SubRoc. The future sub-versus-antisub contest then becomes one of good fire control, adequate weapons capacity, and teamwork and data-sharing with friendly platforms. But with the proper weapons loadout, a submarine and its consorts might even defeat incoming supersonic ASW cruise missiles, or ballistic missile barrages. R&D on submarine-launched supersonic anti-aircraft and anti-missile missiles, and theater ballistic missile defense, become even more potent force multipliers in a world containing MAGIC.
2. The sea/air boundary is asymmetric: It is important to note that for purposes of engineering and design, there is much less stress on a weapon making a high-speed transition from the ocean to the atmosphere, than on one going the other way to make a hard, high-g-force impact with the water's surface tension. In any head-to-head battle with surface or air opposition forces, this gives an advantage to a submarine equipped with the proper weapons. In addition, as mentioned above, the speed of sound in water is approximately the equivalent of Mach 5 in air. Any weapon, or weapons-firing platform, approaching the submarine at less that Mach 5 will give advance warning of its approach, as its engine sounds pierce the water and then propagate on ahead to be detected by the submarine's passive sonars. Furthermore, the viscosity of water is significantly greater than that of air; resistance (friction) to a moving body is much less in air than in water. This presents another asymmetry in a battle between a submarine firing a cruise missile, and a surface ship or aircraft firing a missile-weapon at the sub. In the terminal targeting and impact stage, a missile attacking a surface ship will smash home with tremendous velocity. Last minute close-in defenses have notoriously short periods during which to react effectively. In contrast, the terminal target homing and impact stage of an ASW weapon faces a sudden drop in speed once it enters the water; even if the ASW warhead is itself supercavitating, its speed will drop to some 200 knots after an airborne transit speed of possibly 2000 knots. This gives the submarine a longer reaction time during which to take active measures to defeat the incoming warhead; once again, advantage submarine. This line of reasoning also suggests that greater depth can give a submarine important extra protection, by increasing the distance an inbound air-deployed warhead needs to traverse. (It's the spectrum of adjuvant vehicles, mentioned above, that will allow an SSN or SSGN to reach through the enemy littorals and right into their surf zone, while the parent sub lurks in water of adequate depth.) Thus, we may conclude that the ocean is much more than just a cloak of invisibility. For a submarine the ocean is armor. What's more, that "armor" comes free of any weight or space penalty! Equipped with the proper offensive and defensive weapons, a submarine robbed of its stealth by MAGIC would nevertheless be able to stand and fight against opposition forces, with every expectation of winning.
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