Source : Indian Defence Analysis
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| DRDO’s HSTDV glide vehicle based missile (Image Source: Twitter) |
The speed greater than 5-times the speed of sound or Mach-5 is called Hypersonic Speed. Hypersonic weapons are extremely difficult to detect, and counter given these weapons’ speed, maneuverability, low flight paths, and unpredictable trajectories.
While traditional intercontinental ballistic missiles follow relatively predicable up-and-down trajectory, hypersonic weapons are maneuverable and can fly at altitudes where few military sensors & radars are monitoring. They can conceivably be deployed from land, air and sea.
Types of Hypersonic Missiles
There are two types which are under development and in service with various military of the world. First one is hypersonic cruise missiles, which are powered by an air-breathing Ramjet, Scramjet or Dual Mode Ramjet (DMRJ) engine.
Second one is hypersonic glide vehicles, which reach orbit with a conventional booster before gliding towards a target.
The Hypersonic cruise missiles are powered throughout their flight using the scramjet engine, whereas the hypersonic glide vehicle makes use of their aerodynamic shape to glide towards the target after released from a certain altitude and speed.
The Hypersonic glide vehicle follows zig zag trajectory during their terminal phase not a typical parabolic path making them extremely unpredictable. The Hypersonic cruise missile has comparatively smoother path of motion, but their flight altitude is much lower than Hypersonic glide vehicle, hence their detection in radar is nearly impossible due to earth’s curvature.
DRDO Missiles, note HSTDV and Supersonic Long Range Cruise Missile( SLRCM). May be this is the first picture of these missiles. pic.twitter.com/Zk6LNsoXb2
— Varun Karthikeyan (@Varun55484761) January 15, 2023
DRDO HSTDV & Project Vishnu
As we all know that DRDO has been working on developing a Hypersonic Technology Demonstrator Vehicle or HSTDV which is powered by a scramjet engine and will be used to develop Hypersonic cruise missile. The development of the Hypersonic cruise missile which is expected to be a spin-off of HSTDV powered by scramjet engine has commenced under the name Project Vishnu.
Recently DRDL has released a posted with all the missiles under development by the organization which you can seen on your screen. The most important of them is Hypersonic Cruise Missile based on HSTDV. This is the first official image of HSTDV based missile in our knowledge released by DRDL.
If you look carefully, the HSTDV is mounted on a booster with 6 control surfaces. This booster is expected to be derived from K4 missile rather than Agni missile which was used in HSTDV trial of 2020. On the top part of HSTDV as we can see 4 control surfaces. The missile resembles Russian Zircon & Boeing’s -51 Waverider.
DRDO is working on developing the advance material for scramjet engine which can withstand the thermodynamic stresses in the hypersonic vehicles.
Surface and Air Launched HCM
Two different variants of Hypersonic missiles are likely to be developed under project Vishnu. First one is going to be surface to surface missile with range around 2500KM and expected to enter services by 2024-25.
The second one is going to be a smaller and compact version of air launched cruise hypersonic missile with a range in excess of 700KM that can be launched from an aircraft.
The expected speed of these missiles will range from Mach7-10. Not much of the information is not available this program and in future as the development progress, more information will come on public domain. We can expect changes in its specification as well.
