General Electric Aerospace (GEA) announced that it has successfully tested its hypersonic ramjet that uses a rotating detonation combustion (RDC) at its research centre in Niskayuna, New York according to a company statement on 14 December, 2023.
It is believed that “this could help enable high-speed, long-range flight with increased efficiency” due to the ramjet’s improved propulsion.
A typical air-breathing ramjet propulsion system can only begin operating when the vehicle achieves supersonic speeds greater than Mach 3, or three times the speed of sound. GEA engineers are working on an RDC-enabled ramjet that can operate at lower Mach numbers, enabling a flight vehicle to operate more efficiently and achieve longer range.
Hypersonic refers to aerial objects—including aircraft, missiles, rockets, and spacecraft—that can reach speeds through the atmosphere greater than Mach 5, which is nearly 4,000 miles per hour (6437 km/h).
Using the right materials
Amy Gowder, president and CEO of GEA Defense & Systems, stated: “The highly successful demonstration of the [ramjet] with RDC is an outgrowth of our 10+ years of RDC work.”
The successful high-speed propulsion demonstration is part of a larger portfolio of technology programmes that GEA is developing and scaling to advance hypersonics, including high-temperature materials and high-temperature electronics.
As hypersonic objects travel faster, technical challenges such as atmospheric heating increase exponentially, a paradigm that has historically limited designers. Hypersonic missiles or vehicles will reach speeds of up to Mach 20, causing extreme atmospheric friction which can result in component surface temperatures upwards of 9400°C, thus necessitating the use of ultra-high temperature (UHT) materials to mitigate the risk of thermal damage.
GEA focuses on key advanced materials such as high-temperature ceramic matrix composites, silicon carbride power electronics, additive technologies and advanced thermal management.
The hypersonic scene today
According to a GlobalData thematic intelligence report on Hypersonics (2023), the US, Russia, and China are all testing hypersonic technology, generating fears of escalating global competition for weaponry that has the potential to render current defenses inadequate.
Russia’s use of hypersonic missiles in Ukraine has been confirmed, representing the first combat use of these weapons, and Ukraine has claimed the first successful interception of hypersonic missiles
Although, claims that the Russian Kinzhal missile is a hypersonic weapon is a misconception. During an international press event at MBDA Germany’s Schrobenhausen facility in late October, Dr Dirk Zimper, Director of Future Systems, argued that “a hypersonic weapon system must also be able to manoeuvre” in flight, which Kinzhal cannot achieve.
