Context

Defence Research and Development Organisation (DRDO) successfully flight tested the second indigenously developed ‘Solid Fuel Ducted Ramjet (SFDR)’ propulsion based missile system from ITR, Chandipur, Odisha.

About

What is Solid Fuel Ducted Ramjet (SFDR) system?

• The SFDR propulsion is designed in such a way that it allows for an up and down throttling. This further lets the missile to amplify its speed until it reaches the terminal phase of the flight.
• The speed increases until the point when sharp turns are required to search for highly manoeuvring targets.
• The development and demonstration of SFDR propulsion system is a joint venture of DRDO and Russia.
• Its successful use in missiles will mark India’s entry into a select club of nations that use next-generation missile technology against manoeuvring targets, compromising the effectiveness of conventional missiles.
• SFDR project was started in May 2013 with the objective of developing state-of-the-art SFDR propulsion technology, which can operate at varying altitudes and speeds.

When SFDR missile system was first tested?

• India's new surface-to-air missile, powered by Solid Fuel Ducted Ramjet achieved a speed of Mach 3 during its first test flight in May 2018.
• The missile, which is viewed as the Indian version of the French Meteor, was launched from the Integrated Test Range facility off the coast of Odisha.

How is Solid Fuel Ducted Ramjet better than conventional missile systems?

• The present lot of missiles, which use a booster/sustainer configuration with solid or liquid propellants, have limitations against manoeuvring targets, since conventional missiles, at the terminal stage, cannot provide enough energy to maintain their speed in order to hit the targets.
• SFDR technology will exceptionally enhance endgame manoeuvrability at the terminal stage when the seeker is locked onto a target.
• Ramjets require a rocket booster, or gun launch, to achieve a flight condition where thrust is greater than drag, which for missiles is approximately Mach 2, at which point the ramjet is capable of accelerating to higher speed.
• Since the ramjet propulsion system depends only on its forward motion at supersonic speed to compress intake air, the engine flow-path components have no moving parts.
• Consequently, it has inherent simplicity, reliability, light weight, and high-speed flight capability not possible with other air-breathing engines.
• These attributes make the ramjet a good choice for propelling medium-calibre cannon ammunition at supersonic speed.
• Unlike traditional rocket motor, SFDR can throttle its engine during different phases of flight especially while approaching its target it can throttle up and able to manoeuvre and attack even rapidly manoeuvring targets.

Significance

• It will help the development of extended range missiles such as surface-to-air and long-range air-to-air missiles. Possible uses for the Indian SFDR are in future variants of missiles, including an advanced version of the ASTRA beyond visual range AAM (BVRAAM) expected to extend the Astra Km 1 75 km range to 150 km in the Mk-3 version. According to the DRDO, the SFDR has a range of 120 km with a speed range of 2.3-2.5 Mach.
• Unbound by the diameter of aerial weapons, a ground-launched SFDR would accelerate a missile over 250 km. A potential application of the Indo-Russian SFDR is extended range SAM – such as the futuristic Indian SAM-X.
• Few examples of this tenology are: the MBDA Meteor, Chinese PL-12D and the US Triple Threat Terminator (T-3) missile developed by Boeing as a possible AMRAAM successor.
• The introduction of ramjet propulsion enabled designers in Europe, Russia, and China to extend missile range from 100 km to 200 km, and achieve a maximum speed of Mach 3 – 4, without significantly increasing the missile’s diameter and length.
• In some applications, ramjets were also used to accelerate hypersonic vehicles.