“The approach marks an essential risk reduction step in enabling solid fuel ramjet propulsion to help close a critical performance and cost gap. (Representational image)” (Interesting Engineering, Next-gen ramjet fuel propulsion system for future offensive, defensive missions tested)
A big problem. With ramjet technology. It’s that the ramjet engine cannot start in a static position. The system requires speed. About Mach 1 to ignite the engine. The engine itself has no compressors. The normal way is to launch those aircraft and missiles from another aircraft. Or the rocket accelerates the plane to the needed speed. There is a possibility. To use rockets or jetpacks. The jetpack is a normal jet engine. That accelerates the ramjet-driven aircraft to the speed that it needs. When the ramjet is started. The jetpack can be separated. Or the system. It can close airflow into the turbine. Basically, the jet fighter. It can pull the ramjet-driven system. Into the needed speed.
The other answer. It's the rocket ramjet. There is also the possibility of using a flap system. That system closes the engine inlet face when the speed is too low. Then the system uses compressors to inject air into the combustion chamber. When the speed of that rocket ramjet is high enough. The system opens the engine inlet. And lets the air flow in. There is also the possibility of using an ion system.
To accelerate air to the needed speed. The system ionizes air. And then pulls it through the ramjet engine. The dual-mode ramjet (DMR). It can mean a ramjet. That can operate at low speeds. Or it can operate at high supersonic speeds. And speeds over Mach 7. The dual-mode system. It can have both. Ramjet and scramjet engines. The scramjet engine. It's the hypersonic ramjet. The ramjet engine accelerates the system. Into the needed speed.
And then it starts to use the scramjet. Basically, the afterburner is the ramjet engine. That is behind the turbojet. Similarly, the scramjet can act as an afterburner for the ramjet. The scramjet can be installed next to the ramjet. Or a cone in the ramjet. Its mission is to slow the airflow. It must be burned. Or somehow detonated. If that cone can be turned into ash. The scramjet. It can be put after the ramjet.
The new rotating-detonation engines (RDE). They can operate as both engine types. They can operate as scramjets and ramjets.
The difference between a rocket and a ramjet is that a rocket uses internally stored oxygen. A ramjet engine takes oxygen from the air. So, if we replace the rocket engine with a ramjet. That gives those systems more range. The ramjet engine can store more fuel than a rocket. The big difference between a ramjet and a solid-fuel rocket is that the rocket fuel is like explosives. The problem is short burning time. The bright exhaust gas also helps to detect the missile.
The ramjet engine. It can make it possible. To create new long-range ammunition. The ramjet-driven artillery shell. It can operate at long distances. Unlike rocket-propelled shells, the ramjet keeps pressure in the cannon lower. If it ignites after the grenade leaves the tube.
The air-breathing ramjet can burn its fuel much longer. The exhaust gas is colder. And that makes it harder for the satellite to see the infrared signature of those engines. One of the main problems. With ramjet engines. It is this. They use gas or liquid fuel. Solid ramjet fuel. It gives the ability to store that fuel. In hypersonic systems. The high-speed, hypersonic ramjet system can fly at very high altitudes. The speed of the system. It compresses air in the ramjet engine.
The effect is the same. As in cases like the SR-71 “Blackbird”. The SR-71 can fly so high because of its shape. Its shape. It aims. The air cone or pressure wave into the jet engine compressors. Hypersonic ramjet-based systems can fly in the high stratosphere. But lower than satellites. And that system. It can use advanced stealth technology. The ramjet-driven miniature shuttle. It can be shot on a trajectory. By using a ballistic missile. Then that cruise missile dives back to the high atmosphere.
“Simple ramjet operation, with Mach numbers of flow shown” (Wikipedia, Ramjet)
“Diagram of principle of operation of a scramjet engine.” (Wikipedia, Scramjet)
“Breakthrough Hypersonic Dual-Mode Ramjet with Rotating Detonation Combustion” (Nextbigfuture)
SR-71
And starts its ramjet engines. The idea. For those missiles comes. From the Soviet era. Soviets tested or planned the missile. That rises as a high-speed ramjet-driven cruise missile into a high ballistic trajectory. Then that ramjet-driven stage falls back into the atmosphere. And starts its engines. The collapse of the Soviet Union ended those projects. The difference between that Soviet-era system and “Avangard” is that. Avangard is a glider. The hypersonic glider has no active engine system. But that Soviet-era system. It had an active engine system.
The dual-mode ramjet engine is the system. That is even more effective than a ramjet. A Dual Mode Ramjet (DMR) is a ramjet engine. It can operate in both subsonic and supersonic combustion modes. DMR operation. It can be. Obtained using a fixed geometry if the overall Mach number range is not too wide. Like Mach 4 to 8.
The dual-mode ramjet (DMR) engine. It can also mean that. Those engines can operate in high-supersonic and hypersonic areas. If the Russian Zircon missile operates at Mach 8. That means. That missile. It needs. Dual-mode ramjets. Or the system must boost the speed that a scramjet requires using the regular rocket engine. Or could it be possible? That the Russians lied about the speed of that system? Could it be lower? If the missile flies at speeds of Mach 4-6. That requires only a ramjet engine.
I think that. At least the Russians thought. About the possibility. To install the hypersonic “Zircon” missiles on targets by using long-range ballistic missiles. The ballistic missile returns to the atmosphere far away from its target. And releases the ramjet-driven part into the atmosphere. Normally, those Russian hypersonic cruise missiles are launched from ships using a rocket stage. Then the missile starts. To use a scramjet or dual-mode ramjet. The simplest possible dual-mode ramjet engine. It means the ramjet engine with the scramjet afterburner. Simplest way. It's to put the scramjet separately in the missile or aircraft body.
https://interestingengineering.com/innovation/ge-aerospace-hypersonic-dual-mode-ramjet
https://interestingengineering.com/military/next-gen-ramjet-fuel-propulsion-system
https://www.nextbigfuture.com/2023/12/breakthrough-hypersonic-dual-mode-ramjet-with-rotating-detonation-combustion.html
https://theaviationist.com/2023/12/16/ge-aerospace-demonstrates-hypersonic-dual-mode-ramjet/
https://timesofindia.indiatimes.com/defence/international/can-ukraine-stop-russias-zircon-missile-all-about-moscows-mach-9-hypersonic-weapon/articleshow/132276845.cms
https://en.wikipedia.org/wiki/3M22_Zircon
https://en.wikipedia.org/wiki/Avangard_(hypersonic_glide_vehicle)
https://en.wikipedia.org/wiki/Lockheed_SR-71_Blackbird
https://en.wikipedia.org/wiki/Ramjet
https://en.wikipedia.org/wiki/Rotating_detonation_engine
https://en.wikipedia.org/wiki/Scramjet





































