DRDO flourishingly flight tested the solid fuel ducted Ramjet technology(SFDR) in an attempt to make indigenous long-range missiles

-By Nikita Vijay Biliye

In a boost to indigenous missile development programs, India’s prestigious Defense Research Development Organization (DRDO) successfully conducted a flight test based on the Solid Fuel Ducted Ramjet (SFDR) technology. The test was carried out on 5th March 2021, from Integrated Test Range (ITR) at Chandipur, Odisha.

In May 2018, DRDO conducted the first SFDR propulsion technology flight test. Later, in February 2019, the Defense Ministry had flight-tested the second indigenously developed Solid Fuel Ducted Ramjet from ITR in Odisha. The reports said that the team used a booster motor to simulate the air-launch scenario. Eventually, the nozzle-less booster stimulated it to the needed Mach number from the Ramjet operation.

Highlights of the test 

According to the reports, the booster motor, nozzle-less motor, and other subsystems performed as expected during the test fire. The test also proved many technologies including, Solid Fuel based Ducted Ramjet (SFDR) technology. The missile’s performance was tracked using the information captured by Electro-Optical, Radar, and Telemetry instruments. This successful flight-test of SFDR technology would now enable the DRDO to develop a long-range air-to-air missile along with several other technological advantages.

Solid Fuel Ducted Ramjet (SFDR) technology 

The SFDR is a missile propulsion system developed by the Defense Research and Development Organization (DRDO). The project aims at developing the critical technologies, which are required in the propulsion systems, to develop long-range air-to-air missiles in India.

At present, such type of technology is available only in a few countries in the world. SFDR is a missile propulsion system containing the thrust modulated ducted rocket and reduced smoke nozzle-less missile booster. The system’s thrust modulation is achieved through a hit gas flow controller. The technology makes use of a solid-fueled air-breathing ramjet engine.

 What is Ramjet technology?

A Ramjet is a variant of an air-breathing jet engine. Ramjet uses the engine’s forward motion instead of a rotatory compressor to compress the incoming air. It helps the missile to move forward by restraining the movements of the major parts of the engine. Ramjet cannot be used to power an aircraft since it cannot work on zero airspeeds. The range of this aircraft is around 100-200 km. Ramjet pulls out the air in a particular passage and compresses the air for combustion. This helps in moving the aircraft to a speed from a point where it begins generating thrust.

Simple ramjet operation, with Mach numbers of flow shown
Source: WikiCommons

The Ramjet engine consists of Inlet, a combustor, and an exhaust nozzle. The engine inlet takes in high dynamic pressure air and slows the air to a subsonic speed using shockwaves waves. The compressed air then enters into the combustion chamber, where it is mixed with fuel and ignited to reaccelerate the exhaust to a supersonic speed. The exhaust gas gets accelerated again as the gas exits the engine due to the exhaust nozzle’s geometric configuration


  1. https://pib.gov.in/PressReleasePage.aspx?PRID=1702670
  2. https://www.skybrary.aero/index.php/Ramjet
  3. https://www.republicworld.com/india-news/general-news/drdo-conducts-sucessful-flight-test-of-sfdr-missile-system-off-odisha-coast.html


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4 Responses

  1. Vikas Biliye says:

    Is it a radar guided or heat seeking missile?
    Is it only limited to ground targets or also moving air targets?
    How does it perform against steath technologies?

    1. The missile was guided to a certain altitude. This was done to create the simulation of the release from an aircraft. Also, the nozzle-less booster was fired after getting desired results.
      This is mainly used for an air-to-air attack but the range can be increased.
      So far, there is no info on whether this is using stealth technology or not but there is another project The Garden Reach Ship Builders and engineers limited, Kolkata, working to achieve the third stealth frigate for the Navy.
      Dont forget to register with us for future updates.

  2. Amrit Biliye says:

    Very well written. Informative.

    1. Thank you so much for your comment. Don’t forget to register on our website.

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