History of air breathing engine (Ramjet) development programs around the world has been published in books and journals covering no classified information. The previous literatures have been reviewed and highlights are briefly presented here. The ramjet concepts were conceived in the early 1900s, although, actual ramjet testing started after 30 years. Several researchers started rigorous investigation on ramjet and the major challenge was associated with low thrust to weight ratio. China Lake (California, USA) and Rene Lorin (France) and their colleagues investigated obstruction free jet propulsion devices which is currently called ejector ramjet. Finally, a patent was filed by China Lake in the year 1909 for a subsonic ejector ramjet. After that, in 1913 Lorin published the first article on subsonic ramjet, although, in which there was no discussion related to high subsonic or supersonic ramjets. During World War I (WWI), Morize (France, 1917) and Melot (France, 1920) designed a conceptual ejector ramjet which was tested in France and USA; testing continued till 1950s. In 1926, Carter (United Kingdom) submitted a patent for first practical device like a ramjet for artillery shells, Carter employed a shock (normal shock) induced inlet having conical nose with annular duct or central cylindrical duct. Albert Fono (Hungary) in 1928 received the patent for their conical-nosed LFRJ which has been recognised as the first supersonic ramjet engine. In mid-1930s, France, Germany, and Russia started research on the viable ramjet design. During 1960-1970, Russia sorted out the limitation of zero static thrust of ramjet engine by the integral rocket motor design (SA-4, SA-6, SS-N-19, and AS-17/Kh-31), although, the revolution of integral rocket concept started during 1950s (USA: RARE and CROW). Ramjet development received international attention in the beginning of 1980s, which continues till today. Apart from France, Russia, Germany, USA, and UK, some other countries (since 1990s) such as China (C-310), Israel (Gabriel IV), and India (Akash and BrahMos) are actively involved in research and development programs of ramjet as well.
In India, Akash, a surface to air missile (SAM) has been developed by Defence Research and Development Organisation (DRDO) which is in operational service in Indian Air Force (since 2009) and Indian army (since 2015). The Akash (speed: Mach 2.5) is like the Russian 2K12 Kub (SA-6 Gainful), having an integrated ramjet-rocket propulsion system. The other Indian missile equipped with solid propellant rocket booster with liquid fuel ramjet sustainer propulsion system is the BrahMos, which has been developed as a joint venture between India’s Defence Research and Development Organisation (DRDO) and Russia’s NPO Mashinostroyenia. The agreement was signed by the former President of India and a missile technologist, Late Dr. A. P. J. Abdul Kalam and Russia’s first deputy defence minister, Mr. NV Mikhailov on 12th February 1998 at Moscow. The first missile was successfully test-fired on 12th June 2001 from interim test-range Chandipur coast Odisha, India. BrahMos has different variants (surface/sea/air platform): the operational range varies between 450-600 km with flight speed of Mach 2.8-3. It has been inducted in operational service in Indian Army (since 2007), later in Indian Navy (since 2013) and India Air Force. The next-generation BrahMos (BrahMos-II and BrahMos-NG) is also in the development phase. In this context, Late Dr. A. P. J. Abdul Kalam discussed with BrahMos Aerospace to develop hypersonic version of BrahMos missile, to maintain India’s lead in the field.
Dr. Syed Aaly Hashim
Associate Professor, Aerospace Engineering Dept.
Alliance University