The arms race towards hypersonic weapons

• Recent developments have put the spotlight on hypersonic weapons development, especially the advancements made by China and Russia.

About Hypersonic Weapons

• They are manoeuvrable weapons that can fly at speeds in excess of Mach 5, five times the speed of sound.
• They are capable both of manoeuvring and of flying faster than 5,000 km per hour, which would enable such missiles to penetrate most missile defences and to further compress the timelines for a response by a nation under attack.
• Most hypersonic vehicles primarily use scramjet technology.

Types:

• 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 HCMs are powered by high-speed, air-breathing engines, or scramjets, after acquiring their target.

What is a Ramjet engine ?:

• It is a form of air-breathing jet engine that uses the engine’s forward motion to compress incoming air without an axial compressor or a centrifugal compressor.
• Ramjets work most efficiently at supersonic speeds around Mach 3 (three times the speed of sound) and can operate up to speeds of Mach 6.
• Ramjet powered missiles provide greater range and a higher average speed compared to missiles powered by solid propellants.

Scramjet :

• A scramjet (supersonic-combustion ramjet) is a ramjet engine in which the airflow through the engine remains supersonic, or greater than the speed of sound.
• Scramjet powered vehicles are envisioned to operate at speeds up to at least Mach 15.
• In the chamber, the air mixes with the fuel to ignite supersonic combustion but the cruiser’s flight will be at a hypersonic speed of Mach six to seven.
• So it is called supersonic combustion ramjet or Scramjet.

Recent Developments in HyperSonic Weapons:

• China: It tested a nuclear-capable hypersonic missile in August 2021 that circled the globe before speeding towards its target, demonstrating an advanced space capability that caught U.S. intelligence by surprise.

• Russia: In early October 2021, Russia had successfully test-launched a Tsirkon hypersonic cruise missile from a Severodvinsk submarine deployed in the Barents Sea which hit a target 350 km away.

• USA: While the U.S. has active hypersonic development programmes, it was lagging behind China and Russia because “most U.S. hypersonic weapons, in contrast to those in Russia and China, are not being designed for use with a nuclear warhead.

• India: It is also working on hypersonic technologies.

• India operates approximately 12 hypersonic wind tunnels and is capable of testing speeds of up to Mach 13.

• India is also developing an indigenous, dual-capable hypersonic cruise missile as part of its Hypersonic Technology Demonstrator Vehicle (HSTDV) program and successfully tested a Mach 6 scramjet in June 2019 and September 2020.

• This test was carried out by the Defence Research and Development Organisation (DRDO) and demonstrated the scramjet engine technology, a major breakthrough.

• In a scramjet engine, air goes inside the engine at supersonic speed and comes out at hypersonic speeds."