Qs people asked me on science and my replies to them - Part 271

Q: Is Is the Rudram-3 an anti-radiation missile?

Krishna: You usually don’t get full information on these issues as they are defense related.
RudraM-III is often classified as the air-launched quasi ballistic missile with hypersonic terminal stage.

An anti-radiation missile (ARM) is a missile designed to detect and home in on an enemy radio emission source. Typically, these are designed for use against an enemy radar, although jammers and even radios used for communications can also be targeted in this manner.

Most ARM designs to date have been intended for use against ground-based radars. Commonly carried by specialist aircraft in the Suppression of Enemy Air Defenses (SEAD) role, the primary purpose of this type of missile is to degrade enemy air defenses in the first period of a conflict in order to increase the chance of survival for the following waves of strike aircraft. They can also be used to quickly shut down unexpected surface-to-air missile (SAM) sites during an air raid (1).

 ARMs  have nothing to do at all with “nuclear” radiation.

It is referring to electromagnetic radiation, such as light and radio waves. Specifically in this case, the radio waves from a radar unit.

There are three basic ways a missile can use radar to guide on a target.

1. Semiactive radar homing
2. Active radar homing
3. Passive radar homing

Anti-radiation missiles belong to this third set.

Semiactive radar homing means that a missile requires a Fire Control Director. the Fire Control director illuminates the target with a radar beam. The missile has a radar receiver in the nose and homes in on the reflected signal bouncing off the target. These missiles are not “Fire and Forget” as they require an outside guidance in the form of the fire control radar from the firing unit. The Firing ship or aircraft must maintain a lock with the target for the entire flight of the missile to impact

Active radar homing on the other hand requires no fire Control Radar (though one is often used to lock the missile onto the target initially).
Once fired, The missile has it’s own complete radar in the nose including the transmitter, not just a receiver. It sends out its own radar signal and homes in on the reflected signal bounced back. As it requires no guidance from a separate Fire Control Unit, these missiles are Fire and Forget. The Firing ship can change lock to a new target and does not have to keep guiding the missile as it can now find its own way.

Passive radar homing is similar to Semiactive radar homing in that the missile only has a receiver, not the transmitter. But rather than homing on the reflected signal of your own fire control radar… it instead homes in on the radar signal coming from the enemy radar site.

Tl;Dr… The Missile homes in on the radar signal of the enemy radar site, rather than be guided to the target by a friendly radar or its own radar.

RudraM-III is often classified as the air-launched quasi ballistic missile with hypersonic terminal stage.

It is still at a trial stage.

Rudram missiles are nuclear tipped too.

Rudram-I/II/III Next generation anti-radiation missiles : This has been listed as an antiradiation missile by Wikiwand (2). That’s all we know about it.

Footnotes:

1. Anti-radiation missile - Wikipedia
2. List of missiles by country | Wikiwand