(cont2)
It should be noted that there are still weak points to this configuration, the most striking is that it is more sensitive to the variation of the center of gravity and the aerodynamic focus compared to that with more control surfaces. However, the combustion of propellant will quickly place the center of gravity of the missile forward, the aerodynamic focus changes and especially non-linearly. This type of "simple" configuration naturally imposes stronger constraints on the design of the control system.
After the aerodynamics then comes the choice of propulsion. Most Air-Air missiles today use the solid propellant rocket engine, and the disadvantage of a conventional rocket engine is its relatively short working time (as long as the propellant is totally consumed). So when the missile arrives at the end of its course - towards the right part of its flight envelope - it will fly only with its inertia and this induces a lower maneuverability. It is then said that energy management is not ideal.
When the announced range of some Air-Air missiles is 100 kilometers, in reality it rarely exceeds 50 kilometers in practical use.
To overcome the problem and increase the effective range of Air-Air missiles, the missiles first opted for the ramjet solution. This type of propulsion has many advantages - on the one hand, the missile no longer needs to transport its own oxidants, because air plays this role, so the mass of the missile is more easily controllable. On the other hand, the operating time is also longer, the energy management throughout the missile flight is therefore better managed, the maneuverability at the end is superior to that of the missiles with conventional rocket engine.
But despite these very interesting advantages, which have moreover justified the development of the Meteor missile in Europe, the ramjet engine unfortunately generates other disadvantages - A ramjet requires compulsory air intake and with a flying speed It is necessary to ensure that the air can enter the engine whatever the flight profile, even at high incidence. The design of the integration of the air inlets with the missile cell is therefore relatively more difficult.
The other constraint is also related to these air intakes - they increase the size and volume of the missile, which is not favorable for the integration of the missile in an airplane with an armaments hold, in particular on the new ones New generation fighter aircraft said stealth.
The range of Chinese Air-Air missiles scheduled in the late 90's' (Source: AVIC)
The range of Chinese Air-Air missiles scheduled in the late 90's' (Source: AVIC)
For all these reasons, the Americans, Russians and Chinese all quickly abandoned their ramjet missile projects - such as the first version of R-77M or the first version of PL-12D and PL And turn to another technological path which is the double-pulse rocket engine.
It consists of separating the solid propellant from the missile in two or more segments. Once launched, instead of consuming all of its propellant at once as in a conventional rocket engine, the missile consumes only one segment of its propellant to achieve cruising speed and altitude and the second segment Lights up according to the need and therefore the flight profile of the missile.
Double pulse rocket engine (Source: DRDO)
Double pulse rocket engine (Source: DRDO)
This mode of operation makes it possible to considerably extend the range of an Air-Air missile, the AIM-120D for example practically doubled its range compared to the previous versions thanks to this. By far the same interest can be found in a space launch with a cryogenic stage where the engine extinguishes before re-igniting after a planar orbital flight in order to save its fuel and thus increase the carrying capacity of the launcher Less fuel to carry so more load to be mounted for a constant capacity).
Several Chinese missile manufacturers, such as the CASC and CASIC, have mastered the technology of the double-pulse rocket engine for almost 10 years. The ABM HQ-26 missile developed for the Chinese Navy as well as the Air-Air PL-15 missile of the Chinese Air Force are among the new missiles that have implemented this type of motorization.
General Hawk Charlisle of Air Combat Command of the United States expressed his concern, in a conference that took place in September 2015, on the range of PL-15 which is estimated to be nearly 200 kilometers. It considers that "exceeding (in performance) the Chinese missile PL-15 is an extremely high priority".
Charlisle says outmatching the Chinese PL-15 air-to-air missile in particular is an "exceedingly high priority"
The new Chinese missile BVRAAM missile PL-15 on a J-11B
The new Chinese missile BVRAAM missile PL-15 on a J-11B
And on the new missile that appeared under the J-16, it can reasonably be thought that it is also powered by a double-pulse motor.
With a much larger size, an aerodynamic configuration optimized for high speed, and potentially an adequate engine allowing to lengthen the flight distance, one can deduce from it, without too much mistake, that it is an Air missile -Air of very long range, at least superior to that of the PL-15.
Once these hypothesis work done, one can ask the most important question - Was it designed why?
Since the bombing of the Chinese embassy in Belgrade by NATO air forces in May 1999, the number of published research papers shows that the subject of how to reduce the advantage of the Which has become a high priority for the Chinese army, including the removal of so-called high-value or high-threat targets such as AWACS, tanker planes and strategic bombers.
Many associated projects have emerged very quickly, first in the field of surveillance with the increase in the development of OTH, V / UHF, passive, MIMO ... radars, but also "offensive" weapons such as defense missiles Anti-aircraft.
The SAM HQ-8 system, very little known to the public until now, is part of one of these multiple projects. This Sol-Air missile weighing nearly 2 tons and equipped with a Solid / Liquid mixed jet engine is specifically designed to drive AWACS over a distance of 400 kilometers. The system, developed by the CASIC group, had successfully completed its last closed circuit test in 2013.
This new Air-Air missile would, in my opinion, be another response to the same need. Although we are lacking official data, we know that to increase the probability of "kill" against these types of targets, which are usually well escorted with a carefully calculated flight route, That the effective range of the missile is at least greater than that of target detection.
