China’s hypersonic glide vehicle test

• Recently, it has been reported that China tested a nuclear-capable hypersonic glide vehicle that circled the globe before speeding towards its target.
• Several countries, including the US, Russia and China, are developing hypersonic missiles which travel at a speed five times that of sound.
• Though slower than ballistic missiles, they are harder to intercept and can be manoeuvred.

Hypersonic Speed and Technology:

About:

• Hypersonic speeds are 5 or more times the Mach or speed of sound.
• Mach Number: It describes an aircraft’s speed compared with the speed of sound in air, with Mach 1 equating to the speed of sound i.e. 343 metre per second.

Orbital Bombardment System

• Fractional Orbital Bombardment System (FOBS) is not a Chinese discovery.
• In the 1960s, the Soviet Uniondeveloped an orbital bombardment system that could carry a nuclear weapon into orbit at a lower trajectory than a traditional fixed-trajectory ballistic missile.
• The idea behind FOBS is, a warhead is put into a stable orbit and it deorbits over the target. If the target and the launch position is lined up and the warhead keeps going round, it will complete a circle.

Types (2):

• Hypersonic cruise missiles: These are the ones that use rocket or jet propellant through their flight and are regarded as being just faster versions of existing cruise missiles.
• Hypersonic Glide Vehicle (HGV): These missiles first go up into the atmosphere on a conventional rocket before being launched towards their target.
• Technology Used: Most hypersonic vehicles primarily use the scramjet technology, which is a type of Air Breathing propulsion System.
• This is extremely complex technology, which also needs to be able to handle high temperatures, making the hypersonic systems extremely costly.

Development of Hypersonic Technology in India:

• India, too, is working on hypersonic technologies.
• As far as space assets are concerned, India has already proved its capabilities through the test of ASAT under Mission Shakti.
• Hypersonic technology has been developed and tested by both DRDO and ISRO.
• Recently, DRDO has successfully flight-tested the Hypersonic Technology Demonstrator Vehicle (HSTDV), with a capability to travel at 6 times the speed of sound.
• Also, a Hypersonic Wind Tunnel (HWT) test facility of the DRDO was inaugurated in Hyderabad. It is a pressure vacuum-driven, enclosed free jet facility that simulates Mach 5 to 12.

Implications for India:

• Hypersonic technology developments, in the backdrop of growing US-China rivalry and a year-long standoff with Indian forces in eastern Ladakh, is certainly a threat for India's space assets along with the surface assets.
• The offence system operating at these speeds would mean a requirement to develop defence systems at these speeds.