Arms race continues as we head into 2021. Seems like it will be highly unlikely the pursue of additional and modern weapons will ever stop eventually the world could end up in another world war but this time probably be the last world war by just looking at weapons some countries has acquired including nuclear and biological weapon. Now other countries are even jumping further up to take this race even further into space.
Over the last 60 years, intercontinental Ballistic missiles or ICBM’s have become the ultimate deterrent in the defence arsenals of U.S, U.K, Russia, China, France and other countries. This produced the doctrine of M.A.D or Mutually Assured Destruction where if there was a nuclear conflict, no one would come out a winner. But as anti-ballistic missile systems or ABM’s have become better in recent years there is the belief that at some point a first strike by a country with a fully developed ABM system could lead to a winnable nuclear conflict if the retaliatory strike could neutralise. However in the decade or so a new class of hypersonic weapons has been in development that promises to be able to not only deliver a warhead to a target in record time but to do in such a way as to make it almost impossible to shoot them down, so how do hypersonic missiles compare to the decade’s old tech of ICBM’s and are they really any better?
So, what are hypersonic missiles and why are they causing so much concern and new arms race. Well, first we have to look at ICBM’s and the clue is in the name, intercontinental Ballistic Missiles, a ballistic object is one which is following a path under the force of gravity.
A bullet fired from a gun or a bomb dropped from a plane are also examples of ballistic weapons, once they have been fired of released, they follow a predictable trajectory.
An ICBM is no different, if one is launched from one point on the earth and aimed at another point maybe thousands of km away it will follow the same each time it will launch up into space, the launch phase, fly through space where builds up its speed and does any course correction whilst still under power, the mid-course phase then the payload will detach and the warheads and decoys will then fall to their assigned targets, the descend phase. Because the ICMB’s fly high they can be easily observed with radar and space-based tracking. It’s the mid-course phase where they are most vulnerable and their trajectory can be worked out for an ABM’s to intercept.
Whist this is do-able it is extremely difficult and it’s been described as like shooting a bullet with a bullet. The U.S has spent decades in developing ABM systems and it’s only the last few years that they could say they had a workable solution but it can only deal with a small number of incoming missiles at once and is strategically placed to intercept may 2 or 3 coming in over Pacific from North Korea. Now imagine that you could launch a missile that would travel as fast as ICMB but instead of having it just fall from space on to its target it could fly like a cruise missile and take evasive action. This now becomes virtually unstoppable with current ABM systems, and this is exactly what the Russians and Chinese are doing because they believe that if the U.S can make it’s ABM systems tackle a much greater number of missiles the balance of power would shift to the U.S and allow it to make a first strike knowing it could destroy any missile sent in retaliation.
”There are two categories of Hypersonic weapons, hypersonic glide vehicles and Hypersonic cruise missiles”.
Hypersonic glide vehicles work a bit like an ICBM in that they are launched on a rocket into space but they descend to the top of the atmosphere and use the shockwave created by the body of the craft in a phenomenon called compression lift to skim across it, then as it nears its target it drops drown and acts like a steerable hypersonic glider which makes it much more difficult to target by an anti-missile defence system. Hypersonic cruise missiles can also be launched on a rocket or from a plane but instead of going into space they fly through the atmosphere like a normal cruise missile. The difference is in their speed, instead of using a conventional jet engine like in a Tomahawk cruise missile they use a SCRAM jet engine which only works above MACH 4.
so they have to initially boosted to that speed by a rocket, then the SCRAM jet takes over this is where hypersonic missiles have the upper hand because they can use what is known as depressed trajectories to fly much lower but still hypersonic speed of up to MACH 25 for the gliders, so they can get closer to the target before being detected. This not only leaves very little time for the opponent to figure out their course, they can also fly under existing ABM systems which are designed to look for and intercept ICBM’s coming in high from space and on a predictable trajectory. Their hypersonic speed makes them almost impossible to shoot down at low altitude and they can maneuver so their course can’t be predicted.
Hypersonic cruise missiles have also be touted as extremely potent anti-ship missiles because even without a warhead, hitting an aircraft carrier at MACH 5 or above would cause a lot of damage, it might not sink the ship but it would more than likely put out of action. But there is a problem with hypersonic missiles which is affecting all the countries who are developing them and it’s caused by the very thing that gives them their advantage, namely their speed.
Flying at hypersonic speeds in the atmosphere creates a tremendous amount of heat which increases with speed. The SR-71 Blackbird spy plane flew at MACH 3.2 at 70,000 F where the air is only about 5% the density of that at sea level and that caused the leading edges of its wings to heat up to 560 degrees Celsius, which is hot enough to melt some aluminum alloys. The warheads of ICBM’s also travel at hypersonic speeds during their final descend stage but only for a minute or two, and use an ablative heat shield to protect them much like returning spacecraft.
Hypersonic weapons on the other hand, travel the almost their entire journey which could thousands of kilometers at MACH 5 and above. At sea level where the air is at its descends the maximum speed of hypersonic missiles is about MACH 7. The heat created at these speeds can cause the material that the missiles are made of to exceed 2000 degrees Celsius so they have to be made of exotic composites.
At these temperatures the air starts to chemically react with material causing it to break down. It’s also hot enough to cause plasma to form around the vehicle which can affect the CPS guidance systems and course correction commands sent to it from outside. This also affects the accuracy of the missile.
At hypersonic speeds variations in the wind, temperature and other environmental factors are magnified making it much more difficult to target something like a ship accurately compared to normal subsonic cruise missiles. Hypersonic weapons also places the leaders of the country being targeted in a very difficult position because there is virtually no difference between a nuclear armed missile and a conventional missile when it comes barreling over the horizon at several kilometers per seconds and which so little time to react they might just order an all-out retaliation rather than to see how big the bag is and this why they are seen as so destabilising.
At the moment there is nothing that can stop them except the equally except the equally exotic directed-energy weapons which even further down the pipeline than the hypersonic weapons but with upgraded space based detection it will be possible to track the hot missile bodies almost from their launch which will give about the same amount of warning time as that of an ICBM. So, it’s unlikely to affect the balance of power for now but it doesn’t mean the weapon race will stop but it will continue into future. The U.S has been seen as in a bit of a catch-up situation on hypersonic weapons and both China and Russia taking the lead. The question we should ask ourselves, what good is this technology when this very technology could become the reason to destroy human race for once and all.