Ideal PLA Ground Based Air Defence (SAM etc)??????

That's air launched. Not sea launched. A ramjet requires a certain launch speed to ram the air in to get effective combustion right at the start. You get that from a jet fighter, preferably at supersonic launch speeds. You won't get that from a vehicle on the ground or a ship in the sea.

kanwa report that China for year trying to develop mobile SAM,during the late 80's they develop mobile HQ-2 sam system,but it never enter service.later they develop KS-1 (HQ-12) intend to replace HQ-61,but KS-1 needed 30 minute to prepare the launcher combine with the lesson from bekaa valley and gulf war, realized that KS-1 may be vulnerable to attack by high performance ARM,if the radar were to be taken out,the entire missiles launcher could turn into sitting duck.therefore the missile were relocated to point defense .
according to report China is interesting on SA-17,each launcher has there own FCR.

I don't think KS-1 and its successor KS-1A is point defense. Its more like medium range defense (HQ-12), in relation to the HQ-16 used in the 054A. Probably looking around 50km slant range or effective range. The system has a fairly large PAR so that does not look like its a mere point defense system.

crobato said:

That's air launched. Not sea launched. A ramjet requires a certain launch speed to ram the air in to get effective combustion right at the start. You get that from a jet fighter, preferably at supersonic launch speeds. You won't get that from a vehicle on the ground or a ship in the sea.

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Where do you get your material from? Subsonic launch speeds are more than enough for ducted rocket ramjets. ALVRJ mentioned earlier was launched from a very subsonic A-7. The MA-31, the drone version of Kh-31 bought in some numbers by the US Navy was launched at subsonic speeds ( because the Russian launch rails were so dodgy ) from either an F/A-18 or a QF-4. If you ever see a video of one of these things in flight, the launch rail is rocking side to side slightly in the airflow. After the missile launches the pigtail is twisting around in the breeze and the two launch arms hang in the airflow. They found that occasionally the pigtails did not separate from the missiles, creating an immediate hazard to the launch aircraft. Kludge! Evenutally the folks at Point Mugu adapted the MA-31 to a standard USN launch rail, for safety of flight.



In the second video, shot from in front of the missile you can see the nose movement before flight. It is slight, but this is a large missile. The torque loads this slop put on the wing was not a good thing. Russian stuff really is junk.

Igniting and optimizing are two different things. Optimal combustion of ramjets are dependent on air speed, meaning the speed of the air going into the intake for the ramming effect. The slower the ramjet is, the less efficient it is. As a matter of fact, ramjets are quite inefficient under supersonic speeds and at low speeds, have slow acceleration in relation to turbofans and turbojets. You are asking where this information comes from? Its textbook. Go pick up one.

Missiles is all about packaging and making decision calls on the design. You put a booster to just enable the ramjet missile to ignite means not having a booster optimized to put the missile on an optimal flight path. You're not getting the best bang out of your space. Compared to a ramjet, a rocket can accelerate much faster and reach an optimal ballistic trajectory much sooner.

None of the current ducted ramjets in operation can be adapted to SAM use which requires prodigious amounts of acceleration. How many times do I have to tell you that AIR LAUNCH and GROUND LAUNCH creates specific flight conditions that does not make an AAM with its burn profile good for SAM use without heavy modification and incurs severe range penalties at that. Ground launch missiles have to escape gravity and going up while air launched missiles are mainly going horizontal and then headed down. You keep talking about a ramjet that happens to be air launched. That particular ramjet once it was launched from a surface rail only had its range cut off even further.

If you have time check out a US Navy program called TARASM for Thrust Augmented Rocket Surface to Air Missile. It was to be a surface launched ducted rocket ramjet. There is no reason such a missile won't work. TARSAM was tested but for reasons I will mention later shelved. The only change from something like ALVRJ or Ma-31 for surface launch would be to increase the size of the booster grain to achieve the necessary boost thrust. The boost grain burns out and leaves a hollow tube for the ramjet, which is also solid fueled, but the fuel uses a very different grain than the boost fuel. This is what the US Navy tested, with the first series of tests successful. There is a trade off between the speed of conversion from rocket propulsion to ramjet propulsion, with a lower conversion speed reducing the weight of boost propellant significantly. This is not science fiction, it has been around for a long time. Here is the first page of some more recent research on the topic. You have to pay for the whole paper. DR/SFRJ stands for Ducted Rocket/Solid Fuel Ram Jet.



What killed ramjet missiles for the USN back then was something discovered with Talos intended follow on, called RIM-50 Typhon. At Mach 3.8 that missile was so fast that the fire control radars and computers of the day simply could not keep up with such fast missiles. TARSAM worked, but unfortunately was too fast for those old radars. Btw, TARSAM had a range of 80nm and there was a TARSAM-ER with a range of 160nm.

A big rocket can even go faster. An S-300 missile is said to reach Mach 6.

No one, not the US, not the Russians, not the Chinese, not the Europeans, have any plans or project or even a concept for a ramjet SAM now. The Talos/Sea Fury days have gone past. Ramjets are still useful for supersonic/hypersonic cruise missiles but cruise missiles have different flight profiles and trajectory requirements than SAMs.

Simply said, a rocket always have constant thrust, which is always independent from the air speed and air density. A ramjet does not. A rocket can always immediately seek the optimal ballistic trajectory regardless of speed and air density, whereas a ramjet has to consider a flight path that accounts for speed and air density to achieve optimal performance for its engine.

crobato said:

A big rocket can even go faster. An S-300 missile is said to reach Mach 6.

No one, not the US, not the Russians, not the Chinese, not the Europeans, have any plans or project or even a concept for a ramjet SAM now. The Talos/Sea Fury days have gone past. Ramjets are still useful for supersonic/hypersonic cruise missiles but cruise missiles have different flight profiles and trajectory requirements than SAMs.

Simply said, a rocket always have constant thrust, which is always independent from the air speed and air density. A ramjet does not. A rocket can always immediately seek the optimal ballistic trajectory regardless of speed and air density, whereas a ramjet has to consider a flight path that accounts for speed and air density to achieve optimal performance for its engine.

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Nope, the USAF is considering one right now.







What happens is that these things percolate along for years in R&D almost invisibly, before the technology emerges in an operational form. Other times a technology or new weapon will mature then be shelved for lack of a "customer". Procurement of a "system" requires something called an ICD, for Initial Capability Document, to state a need for some material solution to a perceived "gap" in capabilities. Once a need is identified and it is determined a material solution is required ( as opposed to different procedures or training ) you can ask for money to test and manufacture something.
A lot of interesting toys are developed at different R&D facilities then sit gathering dust because the engineers could not find a customer for their invention. That shouldn't imply the technology doesn't work, or that it's somehow out of date. The R&D work comes out of a different pile of money that is designed to keep the best engineers employed devising new stuff. An example of an after hours garage project that became a great weapon is an anti-ship missile called Skipper II. This was literally a hobby project of some engineers at China Lake ( incidentally Sidewinder was developed at China Lake in an engineer's garage because the Navy would not fund it ). They took a 1000 lb Paveway II bomb and stuck a rocket motor on it from a guided missile. The end product was a lazer guided anti-ship missile with a 1000 lb warhead. Bitchen!
Another good example was Agile. This was the original trust vectored IR missile. It used helmet mounted cuing to slew the seeker, and thrust vectoring for superb maneuverability. Sounds pretty modern, eh. This was a 1970's design. It worked as advertised but was shelved in the 1970's as a cost saving measure. AIM-9L was reckoned to be good enough for the "known threat". Well, the Soviets thought Agile went Black and worked feverishly to come up with something better. Something better was the R-73. When the German's obtained these along with their MiG-29's during unification everyone was shocked at their maneuverability. Our answer is AIM-9X, but the groundwork for AIM-9X was laid back in the 1970's with Agile. There is a very clear progression from one to the other, so we didn't have to start from scratch with a new concept. Good engineering does not go away.

And this is what your links says. Nothing new really. Everything here has been known before, and there are similar projects in other countries.

" 06 June 2005
US Air Force eyes flight of ramjet missile

By Michael Sirak JDW Staff Reporter
Washington, DC

After decades of research, US Air Force engineers say they are now on the cusp of testing in flight a novel solid-fuelled propulsion system designed for next- generation air-to-air missiles.

However, standing in the way of them flight testing this Variable Flow Ducted Rocket (VFDR) system - a type of ramjet - is a lack of funding, since the missile work has to compete with more pressing service priorities. Nonetheless, engineers said they are hopeful that the funding will materialise in the next few years.

Developmental efforts by the Air Force Research Laboratory (AFRL) to date have matured the preliminary flight design of a VFDR-powered missile concept.

While Europe's MBDA is developing the ramjet-powered Meteor beyond-visual-range air-to-air missile, the VFDR concept is the only US air-to-air system of this ilk.

The AFRL's 7 in-diameter VFDR model is in the same size class as the AMRAAM, and its inlets have been sized for compact carriage in the internal weapons bays of the F/A-22 Raptor and F-35 Joint Strike Fighter, in addition to other AMRAAM carriage concepts, said Fred Davis, technical director of the directorate's assessment and demonstrations division. The AFRL is "very encouraged" by the design, Davis told JDW. "


It says AIR TO AIR missile. Where does it say SAM? I already told you that the flight profile and requirements of an AAM is different from a SAM. Come back to me when you actually have a real ramjet SAM project.

ramjets rely on atmospheric conditions to obtain optimal velocity, in which random air pockets of thin and dense clustered air can alter the ramjet from low low to high speed, so its launch to target is atmospheric condition dependant. while rockets retain constant velocity, without atmpospheric parameters hampering its velocity and range. its purely relied on its combustion and volume of fuel.