As India test-fires indigenous hypersonic missile, here’s how it works

New Delhi: India successfully test-fired a long-range hypersonic missile from the APJ Abdul Kalam Island off the coast of Odisha on Saturday. 

This hypersonic missile is designed to carry various payloads for ranges greater than 1500km for all the Services of the Indian Armed Forces.

This missile has been indigenously developed by the laboratories of Dr APJ Abdul Kalam Missile Complex, Hyderabad along with various other DRDO laboratories and Industry Partners.

How hypersonic missiles work

Describing a vehicle as hypersonic means that it flies much faster than the speed of sound, which is 761 miles per hour (1,225 kilometers per hour) at sea level and 663 mph (1,067 kph) at 35,000 feet (10,668 meters) where passenger jets fly. Passenger jets travel at just under 600 mph (966 kph), whereas hypersonic systems operate at speeds of 3,500 mph (5,633 kph) about 1 mile (1.6 kilometers) per second and higher, according to a newsdrum report.

Hypersonic systems have been in use for decades. When John Glenn came back to Earth in 1962 from the first US crewed flight around the Earth, his capsule entered the atmosphere at hypersonic speed.

All of the intercontinental ballistic missiles in the world's nuclear arsenals are hypersonic, reaching about 15,000 mph (24,140 kph), or about 4 miles (6.4 km) per second at their maximum velocity.

ICBMs are launched on large rockets and then fly on a predictable trajectory that takes them out of the atmosphere into space and then back into the atmosphere again.

The new generation of hypersonic missiles fly very fast, but not as fast as ICBMs. They are launched on smaller rockets that keep them within the upper reaches of the atmosphere.

There are three different types of non-ICBM hypersonic weapons: aero-ballistic, glide vehicles and cruise missiles. A hypersonic aero-ballistic system is dropped from an aircraft, accelerated to hypersonic speed using a rocket and then follows a ballistic, meaning unpowered, trajectory. The system Russian forces used to attack Ukraine, the Kinzhal, is an aero-ballistic missile. The technology has been around since about 1980.

A hypersonic glide vehicle is boosted on a rocket to high altitude and then glides to its target, maneuvering along the way. Examples of hypersonic glide vehicles include China's Dongfeng-17, Russia's Avangard and the US Navy's Conventional Prompt Strike system. US officials have expressed concern that China's hypersonic glide vehicle technology is further advanced than the U.S. system.

A hypersonic cruise missile is boosted by a rocket to hypersonic speed and then uses an air-breathing engine called a scramjet to sustain that speed.

Because they ingest air into their engines, hypersonic cruise missiles require smaller launch rockets than hypersonic glide vehicles, which means they can cost less and be launched from more places.

Hypersonic cruise missiles are under development by China and the US.

The US reportedly conducted a test flight of a scramjet hypersonic missile in March 2020.

The primary reason nations are developing these next-generation hypersonic weapons is how difficult they are to defend against due to their speed, maneuverability and flight path.

The US is starting to develop a layered approach to defending against hypersonic weapons that includes a constellation of sensors in space and close cooperation with key allies. This approach is likely to be very expensive and take many years to implement.

Unique threats hypersonic missiles pose

With all of this activity on hypersonic weapons and defending against them, it is important to assess the threat they pose to national security. Hypersonic missiles with conventional, non-nuclear warheads are primarily useful against high-value targets, such as an aircraft carrier. Being able to take out such a target could have a significant impact on the outcome of a major conflict.

However, hypersonic missiles are expensive and therefore not likely to be produced in large quantities. As seen in the recent use by Russia, hypersonic weapons are not necessarily a silver bullet that ends a conflict.