HYPERSONIC WEAPONS: BACKGROUND AND ISSUES

India Surging Ahead in Missile Technology

1. The Hypersonic Technology Demonstrator Vehicle (HTDV) Test. India on 07 Sep 2020, successfully test-fired HTDV. With successful firing of the HTDV, India is the fourth country in the world after the US, China and Russia to develop this technology. Operationalization of this capability will facilitate development of missiles that will travel at six times the speed of sound. Further, HDTV mounted weapons will enable a dynamic and responsive long range time critical strike capability making our number one adversary China vulnerable to a possible cruise missile attack. Even without having the Hypersonic capability, India possess the world’s best and the fastest short range supersonic cruise missile Brahmos which travels with a speed of 2.8 Mach. With proving of HTDV technology India is now truly a world leader in hypersonic rocket technology. Also, US, Russia and China have this capability. Being a dual use technology, it will find usage in defence and civil sectors. Likely employment in defence would be to targets road mobile missile launchers of the adversary. In the civil sector, this technology can be used to launch satellite at very low cost.
2. Important Details. HTDV is an unmanned aircraft designed to fly at speeds above 5 Mach. The Indian vehicle achieved a speed of 6 mach. The hypersonic vehicles are powered by scram-jet engine. A cruise missile continuously propels itself in air by burning fuel- similar to an air craft. It follows a straight-line path, and can fly low to avoid detection. See figure 1 below. Further, since it travels like an aircraft it needs to carry fuel. This restricts the range of the missile. In comparison to cruise missiles, ballistic missiles depend upon initial force of delivery which takes it upto its intended target. Ballistic missiles after the initial launch travel under the influence of gravity. Simply put ballistic missile’s operation is like throwing a stone whose range depends on quantum of force used by your hand. In a scramjet engine of a hypersonic vehicle, air flow is supersonic throughout, and only starts after the vehicle reaches a certain velocity. This minimum velocity is achieved by other means of propulsion like a rocket engine.

Figure 1: Source: CRS image based on an image in “Gliding missiles that fly faster than Mach 5 are coming,” The Economist, April 6, 2019, https://www.economist.com/science-and-technology/2019/04/06/gliding-missiles-that-flyfaster-than-mach-5-are-coming.

• Hypersonic Weapons. While HTDV is a dual technology vehicle, its use in defence programme will be of greater concern to India as both Russia and China have been focusing on the development of hypersonic weapons. A Congress Research Service report suggests that their weapon programmes are in final stages of development. The focus of Russia and China appears to develop nuclear hypersonic weapons. There are two types of hypersonic weapons. 1) Hypersonic glide vehicles (HGV). These are launched from a rocket before gliding to a target. 2) Hypersonic cruise missiles which are powered by high-speed, air-breathing engines, or “scramjets,” after acquiring their target. India has currently demonstrated the hypersonic cruise missile technology.

Status of Other Countries

• The United States has so far actively pursued the development of hypersonic weapons— that fly at speeds of at least Mach 5—as a part of its conventional prompt global strike program. In recent years, the United States has focused such efforts on both the hypersonic glide vehicles and hypersonic cruise missiles. However, in the US many experts and policy makers feel that “hypersonic weapons lack defined mission requirements, contribute little to U.S. military capability, and are unnecessary for deterrence.” Accordingly, it is going slow on the hypersonic weapons programme. On the other hand Russia and China have shown growing interest in these technologies.Both Russia and China, have a number of hypersonic weapons programs and are expected to field an operational hypersonic glide vehicle— potentially armed with nuclear warheads shortly. Most U.S. hypersonic weapons, in contrast to those in Russia and China, are not being designed for use with a nuclear warhead. Hence, US conventional hypersonic weapons would require greater accuracy and therefore, more challenging to develop vis a vis that of Russia or China.
• As far as India is concerned, we have demonstrated our capability to develop hypersonic cruise vehicle technology. Suffice it to mention here that we have truly entered the league of world leaders in missile technology. We need to thank our former President Dr. A.P.J. Abdul Kalam, commonly known as the missile man of India and the other scientists who carried forward his effort for the successful test of this technology.