NMD — The Limits of Technology

Columnist Col (Retd) EAS BOKHARI looks at what technology is offering for NMD.

During the cold war period, and after this every US President had been worried about a possible attack on the US mainland by ICBMs. President Reagan had a passion for the impossible and put up an architecture better known as SDI (Strategic Defence Initiative) in his epoch making speech on 23 March 1983 in which he appealed to the US scientists to produce an architecture to ‘zap’ hostile ICBMs, and thus provide security (he thought that total security could be provided) to the US nationals. 

SDI was a powerful idea, but at the same time it had been conceived and floated by people who had but little knowledge of practical engineering difficulties required for negating the on rushing hostile ICBMs. Reagan put up an outfit SDIO (Strategic Defence Initiative Organisation) under a very capable US Air Force General, Gen Abrahamson (who is also considered as the main proponent of the famous F-16 fighter aircraft). 

Some 6 billion US dollars were set aside for initial research as the basic work was to be done in the field of research. This was so because the well meaning ABM Treaty 1972 specifically prohibited manufacture and deployment of anti-ballistic missile hardware. With the passage of time, and with the Soviet threat receding, SDI became too expensive and partially unworkable as the US scientist community had not been consulted while this grand scheme of things was conceived. I suppose the main proponents (initially) of the scheme were politicians and defence contractors who thought that whatever is thinkable is also possible. Actually this was not all that simple. 

Some wise physicists like the Nobel Laureates Hans Bethe and Dr. Garwin of the Union of Concerned Scientist opposed the scheme of things tooth and nail. A very elaborate treatise was put up by the Union of Concerned Scientist depicting the practical difficulties of such a grandiose scheme of things. 

With the break up of the Soviet Union, and possibly pressure from the scientific community at home the grand scheme was relegated to a saner initiative, a sort of a down sized SDI which is better known as NMD (Nuclear Missile Defence), and the SDI started reflecting ‘sane Defence Initiative’ and not the grand ‘Strategic Defence Initiative’ as visualised by President Reagan. This grand scheme of things is shown in the inset. It has a number of options i.e. to deal with a hostile ICBM from ground stations, a satellite platform in space, and possibly from a ship in the sea. It was thought that the most probable choice would be an engagement by lasers from space, and lasers were to incinerate the onrushing missile and thus damage its electrical system, and thus either change its direction or incapacitate it. But can such a powerful laser and platform be provided in space? The scientist community said — No. Not so easily. 

The Gulf War 1991 came and with the Iraqis in possession of older Scud-Bs which had been doctored by the Iraqi engineers and who had sacrificed ballistic potential of the Scud for additional range to hit Tel-Aviv and Al-Riyaz, the

so-called ‘Patriot’ missile of the Ratheon Company took field in Israel and Kingdom of Saudi Arabia. Interestingly, it was claimed that almost 90 per cent Scud hits were claimed by these ground to air missiles which I thought was a business promotional figure than truth, and even President Bush was made to make such an utterance.

I have come across a document of the CRS (Congressional Research Service) where this claim has been totally debunked. This document, however, does not provide any fresh insight into the cause of the destruction of Iraqi Scuds. Most probably the Iraqis had used two scud motors with a single war head and this ballistic modification made the Scud tumble in its later part of flight especially when on re-entry it just broke into two, which surely was not the handiwork of the Ratheon’s ‘Patriot’. All the same the ‘Patriot’ batteries sold well in Middle East, where the oil rich countries buy all their defence hardware off the shelf. Even Japan and South Korea were no exceptions in this regard. They too bought/inducted the Ratheon product.

Hitting or negating a missile in flight is not a joke and naturally not very easy. Quoting from a recent US source ‘Discover, November 2001’, Tim Folger writes in this connection “...United States cannot shoot down one ICBM, let alone hundreds of them...There are no weapons that can hit a slender projectile travelling at nearly 15,000 miles per hour, about 10 times faster than a bullet. So the obvious question has long been: Can such a defensive weapon be built?” 

President Bush is betting it can. “In a speech at the National Defence University in Washington this past May, the President announced his intention to deploy a system that ‘could provide limited, but effective defences’ against ballistic missiles armed with nuclear, biological or chemical weapons....” 

This defence system, advocates say “... is not really intended to thwart an all out attack by a major nuclear power, which might involve advanced weaponry such as MIRVS (Multiple Independently Targetable Re-entry Vehicles) ie missile that bear many warheads. At best they say it could shoot down a few missiles launched by a rogue state such as North Korea, Iran or Iraq, as well as missiles accidently fired from Russia....”

The US President hopes to make such a missile shield a central accomplishment of his administration. He envisions a complex multi-layered defence that counterattacks with ground-based and sea-based interceptor missiles and aircraft equipped with lasers powerful enough to destroy a rocket in flight. The administration has declared it wants to begin building an interceptor missile base in Alaska that could be operational as early as 2004.

It is only fair that Mr. Bush is so serious about the anti-ballistic missile missile as there can be no other active means of negating an ICBM.

Some years back in 1988, even Iraq put up a mock up of such a technology during a weapon exhibition in Baghdad. The equipment was named ‘Al-Faw’. It appears that this anti-missile missile was never made as is clear from the freedom of the US and Allies missile and air attacks on the Iraqi assets during the Gulf War. And then there are news about the Israeli fabrication of the ‘Arrow’ anti-missile missile which I am told is funded by USA, and  the project is in the hands of the Israeli Air Force. And of course I have already discussed the ‘Patriot’ to some extent in the previous presentation.

For any ICBM to be engaged effectively the very first step is to locate the monster. For this specific purpose the US has the NORAD (North American Aerospace Defence) command centre, located deep inside Cheyenne Mountains in Colorado. This centre monitors all missile launches around the world. Data from satellites and global network of radar stations flow into computers at this centre. “Hardly a day passes without the detection of a launch somewhere around the world, such as the Russians firing Scud missiles at Chechens or the French lofting a satellite into the orbit.... But in the 36-year history of the Cheyenne Mountain, there is one type of launch the staff has never seen and does not want to see: an ICBM on its way to United States...” The threat perception, however, is there.

Russia possesses about 5,200 warheads mounted on missiles, probably some 2,000 fewer than the United States. “An accidental launch, or an unauthorised one by a rebellious officer would involve probably at least a few dozen warheads... The commander of a single Russian submarine for example, could fire as many as 64 warheads at the United States enough to kill tens of millions of people....” China is believed to have no more than 20 ICBMs that could reach USA. China also has a submarine with nuclear capability, but luckily the boat remains close to the Chinese mainland. It is considered that within a decade North Korea, Iran and Iraq will be in a position to fabricate multi-staged missiles which could hit targets in the USA. 

A possible threat scenario will be something like this, if it occurs at all. A missile launched from a site halfway around the world can reach the United States within less than 25 minutes. In such an engagement, “within a few seconds, computers plot the missile’s trajectory. If it is head for North American an officer at the NORAD alerts the Pentagon task force and the White House. Major Barray Venable, an Army spokesman at the Cheyenne Mountain operation centre says, the President has exactly two options at that point... He can order a massive nuclear counterattack against the aggressor nation. Or he can wait as the incoming missile or many missiles vapourises a city, or many cities, which will happen whether he retaliates or not.” Given the present technology there is no other option for the President.

At the cost of some repetition “.... As desirable as even a limited shield might be in an uncertain world, physicists and independent defence analysts who have carefully studied the problem of missile defence argue that the President’s plan is deeply flawed, more a product of wishful thinking than sound scientific analysis... ‘The proponents of missile defence for the most part are totally non-technical. Or they are defence contractors,’ says Richard Garwin, a physicist who, with Edward Teller, helped create the world’s first hydrogen bomb 50 years ago.” It is argued that the top levels of the Defence Department are political and managerial and not technical.

Missile defence is a gigantic technical challenge and according to Philip Coyle “For missile defence to be effective, every component — radar systems, satellites, missiles, communication networks, would have to perform flawlessly in the heat of combat.” Coyle had directed the defence departments office of testing and evaluation during the Clinton administration. He says “... All the pieces of the system, which are major systems in themselves, have to achieve reliabilities that military equipment rarely has.” 

Employing a little bit of ballistic rhetoric the flight of an ICBM is a tragic drama that unfolds in three relentless acts: boost phase, midcourse, and reentry. By all consensus the boost phase is by far the best chance to shoot down a hostile ICBM, but tragically it lasts just 300 seconds, the time that a missile takes to clear the atmosphere. A rocket rising into the air presents a clear target, and satellites can easily spot its hot exhaust fumes. Two very different types of weapons are being considered for this stage of negating the hostile ICBM, and neither will be ready for at least several years. These two technologies are ship launched interceptor missiles, and an exotic airborne laser. 

Of these only the airborne laser is in active development presently. Boeing, Lockheed Martin and TRW are trying to equip a modified 747 jumbo jet with upto 17 lasers. Perhaps, even in theory several such aircraft will be needed to fly constantly above such pariahs like Iraq and North Korea, ready to shoot down a missile within a minute or two of its launch.

A number of missile interceptor tests have been carried out in USA, but so far on the whole the results have not been very promising. During one trial, in April 1998, the rocket never left the launch pad due to a programming error. During four subsequent tests since October 1999, the target missile was equipped with a homing beacon. In two of these tests, the interceptor missed the dummy warhead completely.

Then there is another basic problem in this business of missile defence, and according to Coyle “....one of the dilemmas involved in creating a missile defence system is that the offence always has an advantage...They can always figure out how to beat it”. 

Ted Postol, a nuclear physicist and a former advisor to the Pentagon on ballistic missile technology says that there is little chance the airborne laser will be ready in 2008 as its developers say. “...There are lots and lots of technical questions that are unresolved.” He continues “My guess is that it is decades away, if it can be built at all”.

The naval option under these circumstances looks a bit better but a ship launched interceptor will have less than 300 seconds to destroy a missile before it went completely out of range. This leaves little time, perhaps no time, for the President to be consulted about a decision to fire. According to Coyle again “You might have to shoot within as little as two minutes, certainly within three or four....”

Here is another analysis of Postol about the efficacy of the much trumpeted and fabulous ‘Patriot’ in the Gulf War against the Soviet supplied Scuds. I suppose the ‘Patriot’ was designed to deal with fast moving high altitude aircraft and not missiles. And the performance of this anti-missile missile is really sobering. Here is Postal’s analysis. “...Although the exact number of Scuds, Patriot encounters during the war is classified, these are thought to have been about 80. The Army initially claimed that Patriots hit 96 per cent of their targets. Postol found, as did the Government Accounting Office in a separate study (inquest) that the Patriots hit at most 6 per cent, fewer than five out of 80. In fact, Postol could not confirm that any Patriot Missile ever actually hit any Scud missile. So when a target is a missile instead of a plane, the performance of Patriot is not print worthy. 

The purists are still enthusiastic about the NMD whereas the more knowledgeable physicists dub it as unworkable at least for now, and in the very near future. This 1240 seconds battle against a hostile missile is perhaps too technical. Some of the more difficult problems are the procurement of the desired lasers and the platforms in the space. And then for total coverage of the hostile missiles flight a very large number of satellites are needed. All this is mouthful. Then there are the problems of the decoys which can be profitably used by the hostile country.

And then what happens if the engagement is a failure and the interceptor missile misses? Lt. Gen. Ronald Kadish, head of the Ballistic Missile Defence Organisation (BMDO) argued in a testimony before the Senate Armed Forces Committee that there should be sufficient time during the mid-course phase to fire additional interceptors at a hostile warhead. He said, “Multiple shots at the target give a higher probability of being able to hit it”. It appears that Gen. Kadish is not seriously catering for the decoys used by the enemy. 

Gen. Kadish insists, and so has Gen. Abrahmson the first director of SDIO that the critics of the arrangement are too pessimistic. His reply to the critics “...I do not share the assessment that what we are attempting to accomplish with our system is in any way impossible....Over the coming months and years I believe programme results can speak for themselves in responding to the criticism that the (missile shield) cannot operate as designed against the projected counter measure threat that a state of concern may pose”. 

Coyle, Postol and other experts do not share Kadish’s faith and believe that both Russia and Usa has designed missiles which contain decoys and in fact any country who can design a workable missile can easily design a less complicated decoy. The simplest decoys are Mylar balloons, just like those which are sold in the super markets, except that each one is about the size of a house. They reflect radar and present tracking stations with hundreds of problems as they can produce hundreds of of signals. There could also be some other chaff making which makes the problem of tracking really horrendous.

The chaff would envelope the warhead and make it difficult to actually determine the exact location of the real warhead, and in this way the interceptor could sail through the cloud without touching the warhead. Some chaffs could be empty and creating still more problems and false targets. 

The radar stations and satellites the United States use can track the launch and flight of a missile very accurately, but they cannot distinguish decoys from real targets. To do that the missile defence system must rely on a powerful new radar, called X-band, now being tested on Kwajalein Atoll in the Western Pacific. Like all radar, it sends out electromagnetic pulses that reflect back off the targets. This i.e. X-band has a much shorter wave length than any existing radar, just over an inch long, which allows it to resolve details of range, size and shape that remains invisible to standard radar. The prototype is reported to be able to detect objects as far away as 1200 miles. When the radar is fully developed, that range is expected to increase double fold to about 2400 miles. Of course, for an effective ballistic missile defence several such radars will have to be built around the world. 

According to some experts such radars of high resolution properties can create problems of their own, and will reflect off rain or hail in the line of sight between the radar and the object it tracks due to extremely short wave length. 

And let us even believe that the radar does find out the target and distinguishes from the chaff-even then the engagement poses serious problems. Postol points out “...Should the X-band Radar somehow manage to single out the warhead from the herd of decoys, that information might be useless for the interceptor...If the radar correctly identifies an object as a warhead, it does not mean that the kill vehicle will know which object to home in on. The problem is that once the radar has relayed its information to the interceptor, the targets, travelling at about 5 miles per second, will have moved away. And by the time the kill vehicle encounters the targets, they will have been mixed up. “Closing on the flock of balloons, chaff and warhead at more than 15,000 miles per hour, the interceptor would have to rely on its own sensors and would likely miss the warhead....” 

The final part of the tragedy is the brief climatic act i.e. the re-entry phase. This follows the midcourse phase of the ICBM’s flight. This phase is the shortest and may only last 40 seconds or so and chance of interception of a hostile ICBM during this phase is nil. 

Finally, and to sum up Colson provides a homely analogy saying “...We know how to hit a bullet with a bullet, so that is not really the analogy. It’s like when you were a kid and somebody threw a ball at you. You could stop that. But if they threw a handful of rocks you could not stop them all. That’s the problem. We don’t have enough bullets”.