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It is worst of the worst, take anything from that account with a tencere of salt.
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Hypersonic Glide Vehicles and the tech behind simplified:
As most of us know well, a hypersonic vehicle is a platform that travels at speeds in excess of 5 times the speed of sound.
But we must not forget that the speed of sound varies with the density of air and the temperature of air in which it travels. So, at sea level and 15degrees Celsius, the speed of sound is 340m/second. Yet at 11000m altitude and minus 55 degrees Celsius, the speed of sound is 295m/second. So Mach numbers at high altitude and low altitude are attributed to different parameters.
A hypersonic glide vehicle, as the name suggests is a glider – it does not have its own propulsion system and is brought to an altitude of around 110-120 kilometres, with the help of a rocket powered missile. After separating from the launch vehicle, it returns back to Earth in a somewhat gliding manner. At high altitude, after the apogee, a hypersonic glide vehicle moves at an initial speed of more than 6,000 metres per second. As there is hardly any air present at that altitude there is no gliding to speak about in spite of the tremendous speeds it is travelling at. But, once the glide vehicle starts reaching 70km and below on it’s downward flight, it starts to get aerodynamic lift. And can start to glide or bounce over the comparatively thicker layers of air. Hence manoeuvre.
Through it’s flight at high altitudes and gliding at lower altitudes the vehicle can cover very large distances, that would put it in the same level of range as an ICBM.
When the glider is separated from the launch vehicle at high altitude it is virtually at free fall as there is no air with no glide effect and over 6000m/second speed. But as it reaches 70km and below it is having to negotiate air resistance. So it is vital that such a trajectory of low air drag is chosen, that the speed is not too low. Below 15km this resistance will increase to such levels that the speed is no more than 1000m or so when the vehicle hits its target.
A 3000kg rocket can take a 1500kg glide vehicle to the operationally high enough altitude. These glide vehicles have to be small enough to be less noticeable by radars. But due to the size and thus the weight limitations, the terminal speed of the vehicle is restricted.
Another challenge a HGV has is that it has to withstand high tip temperatures due to air resistance that are around 1000degrees Celsius. So heat resistant coatings and materials used become more important. To alleviate the heat problem trajectories of heating and cooling-down phases are applied.
Due to their extremely high speeds until the very last moments, the HGVs are most difficult to be intercepted by anti missile systems. Ground radar stations are capable of detecting small projectiles at around 300 kilometres. Most likely, however, the course of the trajectory cannot be determined because “most” of today’s radar systems only ensure tracking of an object for speeds of less than 1,000 metres per second and a predetermined trajectory.
Weight of the platform is important in its terminal speed. A 105 ton ICBM can hit the target at 3500m/second speed as it still carries a lot of weight even after expending all of its fuel.
As most of us know well, a hypersonic vehicle is a platform that travels at speeds in excess of 5 times the speed of sound.
But we must not forget that the speed of sound varies with the density of air and the temperature of air in which it travels. So, at sea level and 15degrees Celsius, the speed of sound is 340m/second. Yet at 11000m altitude and minus 55 degrees Celsius, the speed of sound is 295m/second. So Mach numbers at high altitude and low altitude are attributed to different parameters.
A hypersonic glide vehicle, as the name suggests is a glider – it does not have its own propulsion system and is brought to an altitude of around 110-120 kilometres, with the help of a rocket powered missile. After separating from the launch vehicle, it returns back to Earth in a somewhat gliding manner. At high altitude, after the apogee, a hypersonic glide vehicle moves at an initial speed of more than 6,000 metres per second. As there is hardly any air present at that altitude there is no gliding to speak about in spite of the tremendous speeds it is travelling at. But, once the glide vehicle starts reaching 70km and below on it’s downward flight, it starts to get aerodynamic lift. And can start to glide or bounce over the comparatively thicker layers of air. Hence manoeuvre.
Through it’s flight at high altitudes and gliding at lower altitudes the vehicle can cover very large distances, that would put it in the same level of range as an ICBM.
When the glider is separated from the launch vehicle at high altitude it is virtually at free fall as there is no air with no glide effect and over 6000m/second speed. But as it reaches 70km and below it is having to negotiate air resistance. So it is vital that such a trajectory of low air drag is chosen, that the speed is not too low. Below 15km this resistance will increase to such levels that the speed is no more than 1000m or so when the vehicle hits its target.
A 3000kg rocket can take a 1500kg glide vehicle to the operationally high enough altitude. These glide vehicles have to be small enough to be less noticeable by radars. But due to the size and thus the weight limitations, the terminal speed of the vehicle is restricted.
Another challenge a HGV has is that it has to withstand high tip temperatures due to air resistance that are around 1000degrees Celsius. So heat resistant coatings and materials used become more important. To alleviate the heat problem trajectories of heating and cooling-down phases are applied.
Due to their extremely high speeds until the very last moments, the HGVs are most difficult to be intercepted by anti missile systems. Ground radar stations are capable of detecting small projectiles at around 300 kilometres. Most likely, however, the course of the trajectory cannot be determined because “most” of today’s radar systems only ensure tracking of an object for speeds of less than 1,000 metres per second and a predetermined trajectory.
Weight of the platform is important in its terminal speed. A 105 ton ICBM can hit the target at 3500m/second speed as it still carries a lot of weight even after expending all of its fuel.
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This is an excellent article. You guys should read it
www.scientificamerican.com
The Physics and Hype of Hypersonic Weapons
These novel missiles cannot live up to the grand promises made on their behalf, aerodynamics shows
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HGV has physical limitations on how much it can maneuver without sacrificing its range. Modern radars like LTMADS or GF300 can provide weapon quality tracks against hypersonic weapons.
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Very good question.
One of the most challenging and demanding parts of the HGV flight is the application of reliable and effective guidance to the vehicle.
Due to high temperature environment a special care has to be taken to overcome problems especially during gliding and terminal stages.
As a good deal of the glide motion incorporates uneven wave-riding flight, it creates a challenge to use effective guidance. During wave-riding, the glide vehicle is subjected to a number of heating-up and cooling down cycles, as well as a bumpy and at times intermittent uncontrollable ride, that causes difficulties for effective guidance.
But with new digitally controlled surfaces and computer programmes, many tests have been performed whereby as an example in one case, after 6000km of flight, the HVG has hit its target with precision.
Review of control and guidance technology on hypersonic vehicle
Air-breathing hypersonic vehicle has great military and potential economic value due to its characteristics: high velocity, long range, quick response…
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A Scramjet engine powered hypersonic missile, if flying through dense atmospheric layers will be subjected to very acute temperature increases at boundary layers due to air molecules ahead of the hypersonic structure are decelerated across the bow shock, and the converted kinetic energy creates very high temperatures at the leading edges.
At lower altitudes, the ambient pressure and density are so much higher that the stagnation and viscous temperature effects are exacerbated.
Typically a re entry vehicle travelling at 6 Mach may generate tip temperatures of 1300Kelvin at 100Km altitude, could have tip temperatures of 2300Kelvln at 10Km altitude.
Scramjet powered missiles, to be effective, have to travel at comparatively lower altitudes and hence denser atmospheric layers. They have to achieve 5 to 10 Mach speeds at these altitudes. This brings with it, a lot of technical obstacles and difficulties to overcome. Materials Science plays a big part in solving these problems. Tungsten, reinforced carbon and carbon composites are used at the affected tips and edges to withstand these high temperatures.
Theoretically a scramjet engine can operate at a maximum altitude of 75km. But lower the flight altitude, lower the chances of detection. However lower the altitude, higher the temperature created limitations.
Most importantly, as Scramjet powered missiles have to travel through comparatively thick layers of atmosphere, they are limited by the fuel they carry. Hence much shorter ranges (less then 10th of) than a HGV.
Below is an interesting article on Zircon, the Russian so called hypersonic scramjet powered cruise missile, and the technical challenges it faces.
The Zircon: How Much of a Threat Does Russia’s Hypersonic Missile Pose?
Russian moves to operationalise the Zircon hypersonic missile represent an important development, but the significance – especially in terms of the current conflict – should not be overstated.
www.rusi.org
Well pakistan has a long range a2a missile and we merged our A2A programs, so like could it involve a new joint long range a2a missile rather than siper based system?
T
Which one is that?
KhanOfEurasia
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I thought the same Way and long Range AA are good for A2/AD Missions, like that Example from the Tweet.
somegoodusername
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Mate, get your information from more, much more reliable sources. Where the hell it says we merged our A2A missile programs with Pakistan. Pakistan is no where that close defence partner of Turkey.
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It was actually reported here.
Official sources stating that,Turkey and Pak will collaborate on A2A missiles.
T
Yes collaborate but where does it say Pakistan has a A2A missile?
They need our help not the other way around.
GIDS has Faaz-2 or is working on it, not sure on status
T
The status is zero,they have a website with some 3D pictures and some specs thats it,nothing more.
GIDS - Road-to-Future
gids.com.pk
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I don’t think that we need something like the AIM-174 when we already have Gökhan in the pipeline.
KhanOfEurasia
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The Question is, can the Range of Gökhan be increased to 400 km, to use it against high Value Assets like Tanker, AWACS &MPA ?
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