Hypersonic Technology

They are manoeuvrable weapons that can fly at speeds of at least Mach 5, five times the speed of sound.
- The speed of sound is Mach 1, and speeds above Mach I are supersonic and speeds above Mach 5 are hypersonic.
They are different from Ballistic missiles which, even though are travel much faster, follow a fixed trajectory and travel outside the atmosphere to re-enter only near impact. Once the ballistic missiles are launched they cannot alter their course.
On the other hand, hypersonic weapons travel within the atmosphere and can maneuver midway which combined with their high speeds make their detection and interception extremely difficult. This means that radars and air defences cannot detect them till they are very close and have only little time to react.

There are two classes of hypersonic weapons, Hypersonic glide vehicles (HGV) and Hypersonic Cruise Missiles (HCM).
HGVs are launched from a rocket before gliding to a target, while HCM are powered by high-speed, air-breathing engines, or scramjets, after acquiring their target.
- The HGV leaves the Earth’s atmosphere and then plunges back into it. To fool the enemy’s radar, this hypersonic vehicle glides through the upper layers of the atmosphere, through a random series of curves and turns.
- HCM is not as fast as HGV, but is designed to fly low and at extremely high speed. This is to take the enemy by surprise. And there is hardly any time for the enemy to hit back.

Hypersonic missiles are a new class of threat because they are capable both of manoeuvring and of flying faster than 5,000 kilometres per hour, which would enable such missiles to penetrate most missile defences and to further compress the timelines for response by a nation under attack.

Friction is the key challenge as the temperatures go up to as high as 2,200 degrees Celsius. And these missiles have to be designed from highly advanced materials which have the capability of withstanding such high temperatures.
Communication is another issue, as it becomes difficult to connect in these hypersonic weapons as the heat builds up a cloud of super-charged particles known as plasma. There is a blackout moment in communications when a spacecraft is re-entering the atmosphere.
Another challenge faced is maneuverability at high speeds, as it puts a lot of pressure on the structure of the missile.

India became the fourth country to have demonstrated this technology after the USA, Russia and China
India is also developing an indigenous, dual capable (conventional as well as nuclear) hypersonic cruise missile as part of its Hypersonic Technology Demonstrator Vehicle programme and has successfully tested a Mach 6 scramjet
In addition, the DRDO established a Hypersonic Wind Tunnel (HWT) test facility
- HWT test facility is a pressure vacuum driven enclosed free jet facility having nozzle exit diameter of one metre and will simulate Mach No. 5 to 12 speeds. Wind tunnels are enormous tubes through which air rushes at great speeds. Air is directed around an item in these tunnels, allowing it to reach the flying stage. The hypersonic wind tunnel is used to test flight characteristics in a hypersonic region of Mach number 5 or more.
A hypersonic version(BrahMos-II) of the BrahMos supersonic cruise missile, a joint development of India and Russia, is also under development.

Hypersonic technological advancements, along with a rising US-China rivalry and a year-long stalemate with Indian soldiers in eastern Ladakh, pose a significant danger to India’s space and surface capabilities.
To maintain a minimum credible deterrence
It can provide advanced security as they are tough to be detected
As interception is tough, it gives a strategic advantage during war
As the speed is high, it can avoid interception and can have increased efficiency over hitting the target
The technology that is needed to develop the hypersonic technology can be used for developing other scientific discoveries that can help our country
In 2021, China had launched a rocket and it had carried a hypersonic glide vehicle (HGV).

Recently the Russian Ministry of Defence announced that it used the hypersonic missile for the first time in the conflict with Ukraine.

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