Tuesday, April 7, 2009

Are US Aircraft Carriers Vulnerable to Chinese Missile Attack ?

North Korea's missile "exploits" have gained much attention recently. Perhaps more ominous, however, is new that its more powerful neighbor may be perfecting a weapon that could alter the balance of power in parts of the Pacific Theater.

The U.S. Naval institute is reporting that Communist China has developed an intermediate range ballistic missile capable of striking an aircraft carrier from a distance of 2000 kilometers. (Note, it is about 1800 kilometers from Shanghai, China to Tokyo, Japan.) The missle reportedly travels at Mach 10 and can reach its target in as little as 12 minutes. The missile relies upon unmanned aerial vehicles, radar and satellites for guidance. The warhead is apparently conventional and not nuclear, and the missile is based upon the DF-21, pictured above on a mobile launcher, thanks for Max Smith, who took the picture and released it into the public domain. The aircraft carrier pictured is the USS Nimitz.

If the report is accurate, America's ability to project power near China, e.g., defend Taiwan, could be greatly diminished, absent effective counter-measures that could thwart such a missile.  Readers might wonder "didn't we face this sort of threat from the Soviet Union during the Cold War and, if so, were we not then able to neutralize such a threat?" The answer is "yes and no." Yes, we faced a threat of ballistic missiles, but only those with nuclear warheads. Soviet ICBMs were not sufficiently accurate to strike a ship on the high seas. The Soviet's most accurate missile, the SS-18 Satan, deployed 10 warheds with a Circlular Error of Probability (CEP) of 500 meters. That is, one half of such warheads would land outside a 500 meter radius of a fixed target, while the other half would land somewhere within that radius. Note that I have emphasized the term "fixed." In wartime aircraft carriers are anything but a fixed target, but can instead travel at over 30 knots (34.5 miles per hour). That's fast enough to cover 8 miles in fifteen minutes, probably the minimum time it would have taken an SS-18 to reach its target in, say, the Atlantic after launch from the Soviet Union. Moreover, like other ships, aircraft carriers need not travel in straight lines, but can instead make high speed turns or zig zag in case of attack. (For a photo of the USS Nimitz making a high speed turn, go here.) I have heard no indication that the Soviets developed ballistic missile targetting systems capable of hitting such moving targets. Absent use of nuclear warheads, then, ballistic missiles simply were not a threat to ships during the Cold War.

Instead, during the Cold War, the main threat to aircraft carriers came from air launched cruise missiles. Launched from bombers such as the TU-22 "Backfire," such missiles would skim above the ocean torward their targets. The AS-16 "Kickback," for instance, had a range of 300 kilometers and could travel at 5400 Kilometers per hour. the older AS-20 had a shorter range and was slower. At the same time, such missiles could only threaten an aircraft carrier if their bomber platforms could make it to within 300 kilometers (about 200 miles) of their targets without being shot down by the carriers' own fighter aircraft or surface to air missiles deployed on escorting ships. As a last resort, a carrier would rely upon 20 mm radar-targetted Vulcan cannons. Those of you who have read Tom Clancy's "Red Storm Rising" will recall that these various layers of defense were not successful in an early engagement that Clancy portrays, in which the Soviet Naval Air Force sinks the French Carrier Foch and cripples the Nimitz and Saratoga with air launched cruise missiles.

For more on Air to Surface missiles, see this Wikipedia entry: http://en.wikipedia.org/wiki/Anti-ship_missile
If the U.S. Naval Institute story is true, then the Chinese must have overcome the obstacles that prevented the Soviets from threatening our fleet with ballistic missiles. If so, there would be several implications to such a development, in no particular order.

1. Hopefully President Obama will ignore Candidate Obama's promise not to "militarize space," whatever that means, exactly. The US should continue to develop its capability to shoot down the sort of satellites that China would employ to guide these missiles.
2. The US may have to accelerate its development of long-range manned and unmanned bombers that can operate from land bases less vulnerable to attack.
3. The US may consider developing smaller, faster, stealthy aircraft carriers less vulnerable to such attacks.