Hypersonic weapons typically travel at Mach 5 to Mach 10 — or speeds of 3,840 to 7,680 miles per hour. A missile traveling at Mach 5 could hit a target 100 miles away in about 1 minute and 34 seconds. A missile moving at Mach 10, meanwhile, could hit a target 100 miles away in about 47 seconds. Attempts to defend against incoming missiles traveling at these speeds leave very little time to deploy countermeasures.
Hypersonic speed is defined as anything above Mach 5. There are two types of weapons emerging: hypersonic cruise missiles and hypersonic glide vehicles. Most long-range missiles follow a ballistic curve that takes them high above the atmosphere and then down through it, a trajectory that can be detected early and modeled accurately. Boost-glide missiles ride a ballistic launcher to attain hypersonic speed, then use momentum to glide at low altitude while taking maneuvers to elude ground defenses. Scramjets use air-breathing engines to travel far, fast, and lower still, making them that much harder to detect and shoot down.
Hypersonic cruise missiles are powered all the way to their targets using an advanced propulsion system called a SCRAMJET which can operate between Mach 5 and Mach 15. These are very, very fast. You may have six minutes from the time its launched until the time it strikes. However, In order to maintain sustained hypersonic flight, a vehicle must also endure the extreme temperatures of flying at such speeds and require ultra high temperature materials.
Boost-glide vehicles, one of the most common hypersonic weapon designs, are unpowered and require some sort of booster to get them to the appropriate speed and altitude, after which they glide back down to earth. Ballistic missiles, or derivatives thereof, have traditionally served as the launch platform for these systems. Tactical Boost-Glide type approach already tested by both Russia and China: a rocket motor boosts the missile up to hypersonic speed, after which it glides to the target. The goal is to “skip” off the atmosphere like a skipping stone over water, allowing it to go vast distances at extreme speeds
“It’s like a plane with no engine on it. It uses aerodynamic forces to maintain stability to fly along and to maneuver,” said Rand senior engineer George Nacouzi. What’s more, Moore notes that because it’s maneuverable “it can keep it’s target a secret up until the last few seconds of it’s flight.” . Getting this to work requires progress in aerodynamics, stability, and controls, as well as materials, Bussing said. 3D printing can help in all these areas.
Hypersonic cruise missiles can fly at altitudes up to 100,000 feet whereas hypersonic glide vehicles can fly above 100,000 feet. An “air-breathing” hypersonic vehicle approach allows less range than boost-glide but greater maneuverability. Air-breathers can also be significantly smaller. A rocket has to carry large amounts of oxidizer to burn its fuel. A jet just sucks in oxygen from the atmosphere. But normal jets don’t have to suck in air moving at Mach 5-plus. A jet that works at hypersonic speeds will require some breakthroughs — and, again, 3D printing can help grow the exotic components.
Systems that operate at hypersonic speeds—five times the speed of sound (Mach 5) and beyond—offer the potential for military operations from longer ranges with shorter response times and enhanced effectiveness compared to current military systems. General John Hyten has stated, hypersonic weapons could enable “responsive, long-range, strike options against distant, defended, and/or time-critical threats [such as road-mobile missiles] when other forces are unavailable, denied access, or not preferred.” Conventional hypersonic weapons use only kinetic energy”energy derived from motion”to destroy unhardened targets or, potentially, underground facilities.
The lattermost is particularly important because most hypersonic vehicles being tested today are boost-glide weapons, which are dropped from an aircraft, boosted to hypersonic speed at a high altitude by a rocket, then glide down to their target. This means that the missile has to be launched at a very long distance and requires the target to be in a more or less predictable place when the missile arrives. Russia recently unveiled a weapon that is boosted by a rocket to an astonishing Mach 27. China showed off a rocket-boosted hypersonic glide vehicle (HGV) of its own, the Dongfeng-17, in a recent military parade. The United States, meanwhile, is testing several hypersonic weapons. “It’s a race to the Moon sort of thing,” says Iain Boyd, an aerospace engineer at the University of Colorado, Boulder. “National pride is at stake.”
Militaries developing Hypersonic cruise missiles powered by Scramjet engines
Militaries are now building Hypersonic cruise missiles require scramjet propulsions systems that can operate at hypersonic speeds. This would allow the weapon to be launched at a low altitude and closer to the target, and would produce a more maneuverable missile that would be harder to detect. US Russia, and China are building hypersonic cruise missiles. Australia is collaborating with the United States on a Mach 8 HGV, and India with Russia on a Mach 7 HCM. France intends to field an HCM by 2022, and Japan is aiming for an HGV in 2026, the U.S. Congressional Research Service noted in a July 2019 report.
Russia’s air-launched cruise missile dubbed “Kinzhal,” which means “dagger” in Russian, has been tested at least three times and was mounted and launched 12 times from a Russian MiG-31 fighter jet. In July 2021, Russia’s military has announced a successful test launch of its new Zircon hypersonic cruise missile. The Russian defence ministry said that the missile, launched from an Admiral Groshkov frigate in the White Sea, successfully hit a target more than 217 miles away on the coast of the Barents Sea. The defence ministry added that the missile flew at Mach 7, or seven times the speed of sound, approximately 5,381 mph.
Russian president Vladimir Putin has said that the missile would be capable of flying at nine times the speed of sound, and would have a range of 620 miles. He added: “Equipping our armed forces – the army and the navy – with the latest, truly unparalleled weapons systems will certainly ensure the defence capability of our country in the long term”. The Zircon hypersonic missiles can be used on surface ships and
Meanwhile, in August, China announced the first successful testing of a hypersonic aircraft, a feat the U.S. has yet to accomplish. China Academy of Aerospace Aerodynamics, described the August 2018 test hypersonic cruise missile test, “High in the sky over northwestern China, a wedge-shaped unmanned vehicle separated from a rocket. Coasting along at up to Mach 6, or six times the speed of sound, the Xingkong-2 “waverider” hypersonic cruise missile (HCM) bobbed and weaved through the stratosphere, surfing on its own shock waves.” At least that’s how the weapon’s developer, the . The HCM’s speed and maneuverability, crowed the Communist Party’s Global Times, would enable the new weapon to “break through any current generation anti-missile defense system.”
Scramjets, though conceived in the 1950s, still remain a work in progress. In the early 2000s, NASA’s X-43 used scramjets for about 10 seconds in flight. Since 2013, the United States Air Force X-51A Waverider has held the duration record with a 210-second burn that pushed the plane to Mach 5.
In May 2020, workers at the Beijing Academy of Sciences ran a scramjet for 10 minutes, according to a report in the South China Morning Post. The Chinese breakthrough was based on the “world’s first systematic investigation into the effect of hydrocarbon fuel state change on the performance and stability of supersonic combustion”, the article said.
DARPA/US Air Force HAWC project
DARPA, in partnership with the U.S. Air Force, completed a free-flight test of its Hypersonic Air-breathing Weapon Concept (HAWC) in Sep 2021. The missile, built by Raytheon Technologies, was released from an aircraft seconds before its Northrop Grumman scramjet (supersonic combustion ramjet) engine kicked on. The engine compressed incoming air mixed with its hydrocarbon fuel and began igniting that fast-moving airflow mixture, propelling the cruiser at a speed greater than Mach 5 (five times the speed of sound).
Goals of the mission were: vehicle integration and release sequence, safe separation from the launch aircraft, booster ignition and boost, booster separation and engine ignition, and cruise. All primary test objectives were met. The HAWC flight test data will help validate affordable system designs and manufacturing approaches that will field air-breathing hypersonic missiles to our warfighters in the near future.
The DARPA/US Air Force HAWC project’s goal is to essentially build a hypersonic cruise missile that breathes air to feed its engine. The technologies offered should feature ramjet, scramjet or dual-mode propulsion — a major difference from the hypersonic weapons currently under development by the Defense Department, which are all boost glide missiles.
The HAWC vehicle operates best in oxygen-rich atmosphere, where speed and maneuverability make it difficult to detect in a timely way. It could strike targets much more quickly than subsonic missiles and has significant kinetic energy even without high explosives.
To achieve this, contractors Lockheed Martin and Raytheon Technologies are each working on advanced air vehicle configurations that will have a hydrocarbon scramjet-powered propulsion and thermal management system for sustained hypersonic flight during the first free-flight tests. Two variants of the Hypersonic Air-breathing Weapon Concept (HAWC) being developed for DARPA and the US Air Force have completed their final captive carry flight tests and are now cleared for their first free-flight tests within the 2021.
Completing the captive carry series of tests demonstrates both HAWC designs are ready for free flight,” says Andrew “Tippy” Knoedler, HAWC program manager in DARPA’s Tactical Technology Office. “These tests provide us a large measure of confidence – already well-informed by years of simulation and wind tunnel work – that gives us faith the unique design path we embarked on will provide unmatched capability to US forces.” Their upcoming flight tests will focus on hydrocarbon scramjet-powered propulsion and thermal management techniques to enable prolonged hypersonic cruise, in addition to affordable system designs and manufacturing approaches.
Russia and India are seeking to build hypersonic cruise missiles. NPO Mashinostroeyenia, is collaborating with India’s Defence Research and Development Organisation (DRDO) to develop BrahMos-II or or BrahMos Mark II, a hypersonic cruise missile . Currently BRAHMOS AEROSPACE manufactures BRAHMOS I with a range of 300 km and with a travelling speed of 2.8 to 3.0 MACH roughly three time the speed of sound. BRAHMOS I has been described as the fastest missile in the world. BRAHMOS II is expected to have a range of up to 600 km and a speed of Mach 7, this speed is over double that of the current operational version of Brahmos. According to the company’s website, the BrahMos-II will be powered by a scramjet engine instead of a ramjet one. “As a variation of the ramjet,” the company explains, “scramjets allow combustion to occur in a supersonic airflow, thereby expanding the operating range above Mach 4.”
Brahmos II was expected to undergo its first flight test in 2020 and enter in into service in 2025. In 2012, According to Brahmos chief they had carried out series of lab tests at the speed of 6.5 mach. According to some reports in media First prototype of Brahmos hyper sonic missile will be ready by 2024.
Russia’s successful test launch of a new Zircon hypersonic cruise missile in July 2021 has many strategic implications. One of these could be termed as good news for India as it will hasten the development of the delayed BrahMos-II hypersonic cruise missile, a joint India-Russia project. The missile reportedly has a maximum range of 1,000 kilometers, with a flight speed of nearly Mach 7 (and as has been tested, it can go up to Mach 8). It is also spelled as Tsirkon and known as 3M22 in Russia and as the SS-N-33 by the NATO countries.
In 2016, an Indian test vehicle reached Mach 6 with the engine running for just five seconds. In Sep 2020, the Defence Research and Development Organisation (DRDO) performed a major technological feat on September 7 when it flew a cruise vehicle at a hypersonic speed of Mach six for 20 seconds. The DRDO called the cruise vehicle Hypersonic Technology Demonstrator Vehicle (HSTDV). The centrepiece of the HSTDV was the indigenously developed air-breathing scramjet engine, which formed the HSTDV’s propulsion system. If the mission’s aim was to prove this air-breathing scramjet engine in flight, it was achieved.
The critical technologies developed for the HSTDV mission were the scramjet engine and its ignition, sustaining the ignition, ethylene fuel, generation of maximum energy from the engine, development of materials to take care of the high temperatures that occurred due to air friction on the leading edges of the cruiser’s wings, tail surface and nose tip, and controlling the HSTDV with minimum drag and maximum thrust.
Dr. Avinash Chander, former Director General, DRDO, said: “The fuel should be ignited in milliseconds. Not many countries were able to do it at the first instance… Energy generation should be maximum and drag should be minimum.” The ignition should be sustained for the duration set for the flight. The entire HSTDV should be controlled but with maximum thrust.
Joint US-Australian Hypersonic Cruise Missile Moves Ahead
The Defense Department’s joint effort with Australia to develop an air-breathing hypersonic cruise missile took a step forward yesterday, with the Air Force issuing round-two contract options to Boeing and Lockheed Martin. The program, called Southern Cross Integrated Flight Research Experiment (SCIFiRE), is aimed at maturing “a solid-rocket boosted, air-breathing, hypersonic conventional cruise missile, air-launched from existing fighter/bomber aircraft, through the completion of a preliminary design review,” according to the DoD contract announcement.
“The new weapon will be a Mach 5-class precision strike missile that is propulsion-launched and powered by an air-breathing scramjet engine,” states the Australian Air Force website. “It will be capable of being carried by tactical fighter aircraft such as the F/A-18F Super Hornet, EA-18G Growler and F-35A Lightning II, as well as the P-8A Poseidon maritime surveillance aircraft.”
SCIFiRE is an outgrowth of a previous US-Australian collaboration, begun in 2007, called the Hypersonic International Flight Research Experimentation (HIFiRE) program, which aimed to develop baseline hypersonic technologies. “The most recent HIFiRE test, successfully conducted in July 2017, explored the flight dynamics of a Mach 8 hypersonic glide vehicle, while previous tests explored scramjet engine technologies,” explains the Congressional Research Service (CRS) in a report updated Aug. 2021.
SCIFiRE, CRS explains, is aimed at furthering air-breathing hypersonic technologies, with demo tests “expected by the mid -2020s.” A key advantage for DoD in working with its Australian counterparts is the Woomera Test Range, which is one of the largest weapons test facilities in the world. “Australia reportedly operates seven hypersonic wind tunnels and is capable of testing speeds of up to Mach 30,” CRS notes.