Informative post
May be a nuisance question, but since i do not know, i would like to ask, what differs a HGV from a general RV? I have heard the mach 5 theory, but a RV, when separates from missiles during re-entry, has far more speed than Mach 5, why does it not act like HGV does? Is it because of there are also matters of aero dynamics?
Before talking about the differences between HGVs and RVs, let's talk about the similarity between different types of missiles. RVs are missiles "packaged" inside a ballistic missile that is only "ejected" after completing the apogee of its trajectory then "diving" straight towards the target at hypersonic speeds, the HGV is also "packaged" into a ballistic missile , but the difference is that the missile is "ejected" even before completing the heyday of the ballistic missile trajectory, when the reinforcement phase ends, where the HGV dives into the atmosphere and begins to glide at hypersonic speeds, in order to perform leaps to avoid both exoatmospheric and endoatmospheric interceptors. As can be seen, RVs are a type of missile that performs most of its trajectory outside the atmosphere, the HGV in comparison performs jumps in and out of the atmosphere, most of which is made while still in the atmosphere, for this reason is called a "boost-glide" which adopts glide at hypersonic speeds.
In terms of speed, an RV can have higher speeds than an HGV, most certainly do. Most of the time the RV is out of the atmosphere, it gains speeds that are only slowed down when the missile re-enters the atmosphere and starts to suffer atmospheric drag, but even this drag is much smaller than an HGV or HCM, because the RV it just re-enters and dives towards the target, the drag is decreased due to this pre-set trajectory of an RV.
An HGV in comparison trades speeds for altitude/range to evade the defensive systems of the West. Just to clarify the terminal phase of a missile that adopts the boost-glide concept is when it leaves the “glide” phase and stops bouncing in the atmosphere to change speed for altitude/range and dives towards the target until impact. At this stage it does not maneuver as it wants to move towards the target and any corrective maneuver implemented by the guidance system is of small amplitude and likely to be compensated by a sur/air missile, any maneuver in this direction is random step, even to achieve the best target location, some correction needs to be made, from HGV let alone HCM. An advantage of the HGV is that as it only allows defense in the terminal phase (for now and for the next 10 or 15 years) being immune from the intermediate phase (glide) to defend itself, the US would have to have hundreds of defense systems protecting the possible high-value targets. Exoatmospheric intercept systems, on the other hand, are capable of protecting huge areas, even the entire country in the case of the GBI, but tracking is made impossible by the curvature of the earth.
To put the scope into question:
The radar horizon of an object that has reached the apogee of 1200 km is 4500 km(RVs).
The radar horizon of an object in orbit at a height of 150 km is 1600 km away (Chinese Glide-FOBS (G-FOBS)).
The radar horizon of an object 50 km high is 950 km(HGVs).
In all cases, there is enough reaction time for a defense, whether continental, area or point.
Considering all cases as being a speed of 7 km/s, disregarding the parabolic trajectory and variations in speed and aerodynamic drag on reentry.
In the first case there would be a time before impact of 10 minutes.
In the second case it would be almost 4 minutes.
In the third case it would be just over 2 minutes.
The difficulty of intercepting hypersonic threats today, especially HGVs, is not due to their speed but to the altitude at which they fly. The endoatmospheric anti-aircraft and anti-ballistic systems in use today have a vertical range in the range of less than 35 km. HGV-type vehicles fly over 40 km. There is a relatively safe range between 40 and 100 km that is currently not reached by either endoatmospheric or exoatmospheric interceptors. With the exception of THAAD which operates between 40 km and 150 km. The SM-6 and the PAC-3 MSE from 30 km down.
A hypersonic (non-engine) glider does not seem to me to be capable of a trajectory into the atmosphere (even at high altitudes) around the earth due to the loss of speed through friction. Even maneuverability is highly restricted because any wider maneuver at these speeds the loss of kinetic energy is significant.
This current technology of hypersonics offers a greater degree of difficulty because it comes “bouncing” in the atmosphere in order to reach the target by “gliding” and naturally changes its trajectory in a random way, which makes it difficult to intercept in the intermediate phase (glide phase). It will still take at least a decade before there are interceptors that act effectively in this phase (the THAAD is a remote possibility), but in the terminal phase, when it stops gliding and dives towards the target, a hypersonic is not much different from a ballistic reentry vehicle, and in theory just as interceptable as this one, it would give interceptors a kinetic window to shoot down the enemy hypersonic missile. Again, this is in theory. Small maneuvers as well as the altitude at which they plan make interceptor systems very limited, hypersonic missiles are changing a whole concept of missile defense, advances with the THAAD and the PAC-3 MSE are currently in development. The SM-6 some sources indicate it is capable of shooting down a hypersonic missile, but nothing has been confirmed so far by testing.
As I said, some assertions realize that current hypersonic missiles only do the same type of work as previous missiles, but only in a different way, which makes it a promising technology, but not a requirement to have a revolution in the world. military affairs.
It's the same problem 70 years ago and it has never ceased to exist for the simple fact that it is impossible to defend against saturation of ICBMs or SLBMs. If the US launches its ICBMs + SLBMs + cruise missiles with the baits, we're talking about 2000 simultaneous targets – Russia and China have similar capabilities. There is, and never has been, a defense for this. For example (I'm guessing numerically in a hyperbolic way), two hundred of these maneuverable HGVs that cannot be intercepted will do the same job as 2000 traditional ballistic missiles, as several of them will be stopped. And the maintenance costs of 200 HGVs would be much less than 2,000 ICBMs. Some advantage these countries are seeing and are not stuck in a technology of the past decades, a new race is in fact underway around these hypersonic missiles.
ICBMs or SLBMs are ballistic missiles. For example. If you launch one of these from China to the US, you'll have a good idea of where it left off and where it's going to go, just by calculating the trajectory. This makes its interception possible. That's how the entire American ABM apparatus works. Russian and Chinese HGVs, on the other hand, have maneuverability, which makes the calculation for interception impossible. These are totally different concepts.
Forgive me if there is any error in the text, I'm using google translator and it's not a good tool.
