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Can ballistic missiles be used as anti-shipping weapons?

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Sentinel Chicken

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This is an except from article someone had sent me:

Even if the Chinese missiles could not accurately hit the aircraft carriers, shooting them in their direction would allow the Chinese military forces to impose "coercive isolation" on the U.S. aircraft carrier battle groups, keeping them out of the Taiwan Strait combat theater.

There has been speculation that China has developed sub-munitions and canister warheads for the DF-15 and DF-21. What progress has the PLA Second Artillery Force made in developing ballistic missile warheads? The answer to this question can be partly found in China's export of P12 ballistic missiles and the development of warheads for the WS-1B and WS-2 multiple-role rocket systems.

Firstly, China's military has invested heavily in developing blasting warheads, blasting cluster warheads for P12, sub-ammunition warheads, cloud blasting warheads and blasting-burn warheads for ballistic missiles and WS-1B and WS-2, all of which are capable of inflicting mass destruction upon designated targets.

Taking the sub-munitions fitted on the WS-1B as an example, the combat part of the warhead weighs only 152 kilograms; it has 475 munitions; the dispersing area of the sub-munitions is 28,000 square meters, and of course this dispersing area can be reset.

If a DF-15 ballistic missile were fitted with a 500-kilogram warhead, the total number of sub-munitions could be 3.2 times those fitted on the WS-1B. In other words, there would be 1,520 sub-munitions or even more depending on the different weights of the sub-munitions. If the dispersing areas of the sub-munitions were the same, that would mean a dramatic increase in unit strike intensity.

If the ballistic missiles used Russian satellite guidance at the middle course plus a certain kind of terminal guidance system, the threat that a DF-15 could pose to an aircraft carrier is very obvious. Psychologically, this would keep the U.S. aircraft carriers 600 kilometers away from the Taiwan Strait combat theater. And if China chose to launch attacks with DF-21M medium-range ballistic missiles, the so-called "coercive isolation" zone would be much broader. Even if these attacks did not seriously damage the aircraft carrier itself, the sub-munitions assault could destroy the radar, command and communications systems of the aircraft carrier battle group and force it to withdraw from the battle.

I'm a bit hazy on the physics, here, but wouldn't the terminal velocity of an MRBM warhead make hitting a moving target a very difficult proposition at best?

I know that the Pershing II used a radar area guidance mode that had a CEP of about 30m, but that was to the best of my knowledge meant to match radar pictures with radar maps onboard as a form of terrain matching. At least that's how I understood the Pershing II's terminal guidance system.

The only way I can see a hard kill on a carrier would be with a nuclear warhead. Barring that, there's the whole issue of firing ballistic missiles that might be construed as nuclear tipped even if they weren't.

According to the article submunitions could be used to increase the lethal radius but I'm guessing those would have to be very large submunitions or something with its own terminal guidance to be effective as an anti-shipping weapon.

I suspect at the end to the day it's the threat of the weapon rather than its effectiveness that maybe its main use.
 

Michel Van

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last time some State Secretary Propose that (ICBM SSBM without Nuke)
the laugh was loud in World Press and Forums

later State Secretary Rumsfeld lost his job....

back to the Chines Problem

for point of view US DoD
they are consider more backwardly as Russia !

oh yeah, this year China shot a satellite down with there ABM system with First Hit Bulleye

the Yankees cannot Hit They Target ABM without an Transmitter screaming "Here I am" ;D
by the way Wat got Russia for advance nasty surprise for US DoD ? ;)

How hit the "backwardly" Chines the Satellite ?
one: they also used a Target Transmitter "Here I am"
tow: They got State of art guidance system better than US Systems :eek:
Tree: They use GPS signal from US DoD ! (my Favorite theory)

why not ? the Dod Use GPS for Bombardment, Cruise missile Attacks.

a DF-15 and DF-21 with GPS guidance system can hit target in 3 Feet (3 meter) Accuracy
US Aircraft Carrier is bigger...
 

overscan (PaulMM)

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GPS gives 3m accuracy hitting a static target. Hitting a moving target requires some form of homing capability.
 

LowObservable

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Maybe GPS won't be delivering 3 m accuracy to all and sundry when the balloon goes up... and in any case it won't hit a moving target unaided.

The lesson on any over-the-horizon anti-ship weapon is that it needs some targeting assistance. That could come from another aircraft (Bear mission) or the launch platform, or a satellite. If the targeting is good enough it may not need terminal homing (Resultant Fury exercise).

How the people who are talking about TBM attacks on ships think that it will be done, I don't know.
 

SOC

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Michel Van said:
for point of view US DoD
they are consider more backwardly as Russia !

No, they aren't. In the media, maybe, but not in the DoD.

Michel Van said:
oh yeah, this year China shot a satellite down with there ABM system with First Hit Bulleye

It was an ASAT, not an ABM, and there is no evidence that it was the first test. They could have failed forty times.

Michel Van said:
the Yankees cannot Hit They Target ABM without an Transmitter screaming "Here I am" ;D
by the way Wat got Russia for advance nasty surprise for US DoD ? ;)

It would help if you cleaned up your grammar slightly, I have no clue what that bit means.

Michel Van said:
How hit the "backwardly" Chines the Satellite ?
one: they also used a Target Transmitter "Here I am"
tow: They got State of art guidance system better than US Systems :eek:
Tree: They use GPS signal from US DoD ! (my Favorite theory)

4. None of the above: they hit a satellite in a preobserved orbit, something that is relatively simple to do, all things considered.

Also, GPS won't help you in space.

Michel Van said:
why not ? the Dod Use GPS for Bombardment, Cruise missile Attacks.

See previous comment.

Michel Van said:
a DF-15 and DF-21 with GPS guidance system can hit target in 3 Feet (3 meter) Accuracy
US Aircraft Carrier is bigger...

What they need is a quick-reaction MaRV, and then this becomes a lot more interesting.
 

SOC

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LowObservable said:
How the people who are talking about TBM attacks on ships think that it will be done, I don't know.

I took a class on Rocket Propulsion Systems as part of my Master's degree program, and one part of it was to design a new propulsion system or component. I went way outside the box and designed a hypothetical MaRV around a new reactive control system design allowing for PGM-type accuracy with ballistic missile speed. After looking at the dynamics of such an engagement, if you were going to do it effectively, that's the kind of system you'll need: a near-precision MaRV.

Otherwise, you have to use a nuke, and you'll want to detonate it subsurface.

Although, an idea similar to Alarm just popped into my head. Why not throw a package into the upper atmosphere. Braking chutes could slow it and an airfoil could allow it to loiter for a few moments upwards of 100,000 feet. Then you could dispense smaller, slower, less complicated weapons to attack the carrier. The problem there is that you loose the speed advantage that's probably your only hope for getting through AEGIS, but it might be more technologically doable.

I still think the best option is a series of torpedoes into the screws, though.
 

sferrin

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Michel Van said:
last time some State Secretary Propose that (ICBM SSBM without Nuke)
the laugh was loud in World Press and Forums

Sounds like they were missing a few facts as it's completely doable. Targeting is the problem but then that isn't weapon specific. It's just as hard to hit the target with a cruise missile if you can't find it. There is nothing special about attacking a ship from above as both the AS-4 and AS-15 (Kickback) can do that and probably others as well.




Michel Van said:
later State Secretary Rumsfeld lost his job....


How is that relevant to anything here?


Michel Van said:
the Yankees cannot Hit They Target ABM without an Transmitter screaming "Here I am" ;D
by the way Wat got Russia for advance nasty surprise for US DoD ? ;)


You might want to lose the nationalism. This site has been blissfully free of that bull$--t unlike most all other forums which are plagued with it. I don't imagine there is a high tolerance level for it here.

As for the transmitter you might want to read up on the issue (somewhere besides a newspaper). It's function was more to ensure we didn't toss $100 million down the drain. The KKV uses IR sensors and is not dependant on outside sources. Much in the same way you wouldn't just randomly lob an antiship missile out into the sea in hopes of getting lucky the transmitter was a way of ensuring the missile was in the basket if you know what I mean. In service ground based radars would provide that info.




Michel Van said:
a DF-15 and DF-21 with GPS guidance system can hit target in 3 Feet (3 meter) Accuracy
US Aircraft Carrier is bigger...


1. As it'd been pointed out a carrier is a moving target. and 2. you still have to target the thing. Doesn't matter if you can hit within an inch on a moving target, if you don't know where it is your missiles aren't going to be hitting anything.
 

Michel Van

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first
sorry about my bad English

second

sferrin said:
Michel Van said:
the Yankees cannot Hit They Target ABM without an Transmitter screaming "Here I am" ;D
by the way Wat got Russia for advance nasty surprise for US DoD ? ;)

You might want to lose the nationalism. This site has been blissfully free of that bull$--t unlike most all other forums which are plagued with it. I don't imagine there is a high tolerance level for it here.

As for the transmitter you might want to read up on the issue (somewhere besides a newspaper). It's function was more to ensure we didn't toss $100 million down the drain. The KKV uses IR sensors and is not dependant on outside sources. Much in the same way you wouldn't just randomly lob an antiship missile out into the sea in hopes of getting lucky the transmitter was a way of ensuring the missile was in the basket if you know what I mean. In service ground based radars would provide that info.

i m sorry about therm "Yankees" but there ABM system plans are in Europe a "Red Flag for a Bull"
but fact is USA want to install a ABM system in Europe, how has made NONE hit under real condition
(the only Hits were possible by install a transmitter in target Drone were ABM Warhead zooms in )


I m afraid that USA install Nuke on ABM system to have chance to Hit the enemies Target
with that system they risk a new cold war with Russia !

P.S.
Please can some one Explane me, why GPS dosend Work in Space ???
 

sferrin

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Michel Van said:
i m sorry about therm "Yankees" but there ABM system plans are in Europe a "Red Flag for a Bull"

That may be but it's a defensive missile (and there will only be ten of them) so it is no threat to Russia.



Michel Van said:
but fact is USA want to install a ABM system in Europe, how has made NONE hit under real condition
(the only Hits were possible by install a transmitter in target Drone were ABM Warhead zooms in )


Again, you need to go read about the reasons for it and familiarize yourself with testing.


Michel Van said:
I m afraid that USA install Nuke on ABM system to have chance to Hit the enemies Target


You should probably familiarize yourself with the system.
 

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Reality - read the Pentagon's Chinese Military Power 2009 report mandated by Congress, especially pages 20-24 and page 48.
http://www.defenselink.mil/pubs/pdfs/China_Military_Power_Report_2009.pdf
 

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while it is good to be "allowed" back , would SOC's smaller weapons be like those Japanese IR homing headed bombs ? USN survived a lot of 250 kg bombs in WW2 and it is also true that they are unlikely to hit or even survive the Cruisers but they would allow survival of aircraft . A proxy war where a third party provides targeting , and a third rate sandlot can do a lot in this case , can't it ? The only problem would be finding the sandlot .
 

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The Aegis and SM-3 ABM capability come right at hand here. BTW, back in the late 60s early 70s there was some talk in using medium-range SLBM to attack carrier TFs. The thinking back then was to use either nuclear or FAE heads.
 

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The USSR attempted such a system back in the day with the SS-NX-13 (a mod of the SS-N-6 IIRC). For that reason the USN kept the nuclear-armed version of Terrier around for a bit longer than they'd intended. When the USSR gave up on the concept the US got rid of the rest of the nuclear Terriers. As for this Chinese incarnation of the concept it appears to be similar in concept and capability to Pershing II albeit with the antiship capability. PAC-3 has hit manuevering Pershing II RVs in testing. LM is looking into sea-based PAC-3 MSEs (although I don't know if the USN is). As Jonsey frequently points out on Key Pub. though, you still need to be able to supply targeting data to the ballistic missiles. If China can't maintain a track on a carrier then those ballistic missiles are pretty much worthless.
 

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I was unaware of the Soviet system, thanks sferrin!
 

Stargazer2006

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see
http://www.secretprojects.co.uk/forum/index.php/topic,766.msg23779
 

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I may be asking a dumb question here, but is there the possibility of a MaRV that can soft land (for various definitions of "soft", from some sort of lifting body that swoops down in a high G liftup maneuver and trails an inflatable drag anchor to cut speed before ditching, to a very reinforced somewhat blunt body RV with a supercavitating nose that dives into the ocean at a shallow angle before floating to the surface), get GPS bearings and maybe radar contacts or a downlink, and then dump a multiple long range torpedo payload into the water?

The point being, a kinetic kill tungsten rod cluster requires fancy terminal guidance but makes some use of the speed, anything that tries to slow down at high altitude makes easy pickings for AEGIS prior to submunition release (and if the submunitions are parafoil born most of the way down then they are slow enough to be picked off by Phalanx), and anything that dumps submunitions at speed requires a much fancier submunition and still needs fancy terminal guidance.

Going the torpedo route and deliberately getting close to the ocean surface, either by quickly diving, or by using the same effective trick as a sea skimming missile, makes it harder to intercept, and underwater defenses aren't so hot especially with multiple fish in the water.
 

sferrin

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Well. . .apparently DARPA thinks it can deploy an inflatable prop plane from a ballistic missile so I don't see why not. :D
 

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At now,no scientific pubblication or reliable sources have supported the PLA capacity to develop at a operative stage a similar weapon. The greater technical problem in this type of project remain accuracy and ,above all, efficient cooling system for the seeker(the required high precision guide-correction system,instead has been resolved by chinese some years ago-2001,cfr.:DF-21/Cs modification at Jane's defence).
The choice of the principal seeker for terminal acquisition(this ASBN will have,anyhow,space for a muti-mode-radar and passive anti radiation-one)will probably fall on a passive multispectral optical one,above all if the aim is to reach a CEP of less than 26m(the presence of sea and the angle of interception,reward this choice and rule out,ostensibly,all effective employement of classical countermeasures).
While the rapid diffusion of QWIP-Quantum Well Image Photodetector-in the next half decade will give to a evolutive DF-21 seeker the range accuracy and high immunity to countermeasure (togheter with the already mentioned specific, favourable, kinematical and“environmental”elements) to accomplish its mission,the cooling question remain irrisolved,above all if we considere superficial temperature of MaRV –Maneuverable Reentry Vehicles-and remarkable retard of China,above all,respect to USA,in HPCG- Hyperdense Cooling Gel- and SNFB-Subcooled Nucleate Flow-Boiling- research’s field(cfr “Brian Donovan Thermal Management Challenges for Future Military Systems” 2006).
This don’t cancel who the operative deployment of a similar weapon will effectively put USA Navy in a very difficult position,and would require probably many years of research to develop a reliable,credibile defence(HEW will be probably the response's choice).
At now,in fact, the intercepting of also only ONE ballistic missile with these capacity of: cruise-altitude control, speed, ECCM, terminal manoeuvrability and so low involved time from the detection to the impact(in a favourable situation ,about 7-8 minutes!!) is a challenge also for large ground based ABM structures with much more powerful wide-spreaded tracking and supporting systems and much more numerous and efficient intercepting missiles( ground installation don’t suffer for space and weight limitation problems).
But like i have stated at the beginning,from all verifiable accessible sources nothing can likely induce to thinking who this could be a imminent danger.

NOTE for the tempted by easy platitudes: The capacity of movement of a carrier group from the missile launch time to impact has NO TANGIBLE EFFECT on the engagement! At a speed of over MACH 10 (10,3 or 3660 m/s) a DF-21 can cover the entire distance traveled by a carrier at its max speed from the launching istant to its maximum range (2100 km)in about ...3 SECONDS!!and descending from 40 km of altitude it is a angular correction of FEW CENTIMETRES!!!
 

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a DF-21 can cover the entire distance traveled by a carrier at its max speed from the launching istant to its maximum range (2100 km)in about ...3 SECONDS!!and descending from 40 km of altitude it is a angular correction of FEW CENTIMETRES!!!

Are you saying the missile can cover 2000 km in 3 seconds? a better math will be needed
 

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Spring said:
a DF-21 can cover the entire distance traveled by a carrier at its max speed from the launching istant to its maximum range (2100 km)in about ...3 SECONDS!!and descending from 40 km of altitude it is a angular correction of FEW CENTIMETRES!!!

Are you saying the missile can cover 2000 km in 3 seconds? a better math will be needed

"....a DF-21 can cover the entire distance traveled by a carrier at its max speed from the launching istant to its maximum range (2100 km)in about ...3 SECONDS!!"

Now the math: Mach 10,3 = 12.614,4 Km/h or 210,4 km/min , then it cover its max range(2100km)in 9,9809886 minutes,i have rounded up to 10 min. A Nimitz class aircraft carrier have a max speed of 30 Kt/h or 55,56 Km/h.
In 10 minutes the carrier can travel 1/6 of this distance or 9,26 km. Mach 10,3 is about 3,5 km/s (rounded down), a DF-21 then can cover 9,26 km in 2,6457143 seconds (i still have rounded up to 3 second in Nimitz carrier's favour!).
Also the data on the detection time i have gived, are on carrier group favour!! In reality ,in IDEAL conditions ,you cannot track a ballistic missile before 3-4 minutes from launch (but this data is for medium ground-based, DEDICATED ABM sites),but one more time i have gived (without "grounded" reasons) to a carrier group 7-8 minutes of time to find a "fire solution", and ,believe me, this is way a too short time also against ONE only missile(a likely attack will involve 10-15 missiles!! each capable to sunk a wole carrier with one hit!)
 

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Ok, now i understand you better, but then we are talking about relatives, yes these are "3 seconds", but are also "10 km" -if mach 10 is the average velocity-

To guide something even beyond 40-30 km against a mobile target will require in-mid flight guidance, which, most likely will be done by aircraft, or sattelite, at the end , i see that as the most problematic issue, is even possible to remove any kind of seeker, and still the hit will be successful against such big and slow target, terminal seeker is still important though

Taking just the terminal velocity as the average one in not how ballistic works, i think the missile will take even more time to reach the ship

And for demostrative calculation, in general, no more than 3 decimals are needed (actually 2 are more than enough)
 

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SS-NX-13 aka R-27K (4K18)
2.0 to 3.5 MT warhead
 

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voidmage

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I seriously think who the idea you have of ballistic intermediate missiles speed are at least distorted. DF-21 is a SUBOPTIMAL ballistic missile!,for its category its speed is LOW!(and this is one of the reasons PLA selected it for this specific program!).
"Taking just the terminal velocity as the average one in not how ballistic works"
No i don't take ANYTHING! Let me understand...you think i have posted re-entry speed of DF-21? Ah-ah, oh no Spring, Re-entry speed of a MaRV today reach 12-13km/s-also much more-!!!! (for DF-21 the re-entry speed is only 3,7 km/s who is very low for today standard!!),but if the other technical problems(previously cited) was resolved a Mach 10 speed allow the high-orbital corrections necessary to the right alignment to the target,in fact,from 40km of height also 50-60km are only 4-5 cm of angular correction away!!!("To guide something even beyond 40-50 km against a mobile target will require in-mid flight guidance",you confound cruise missiles-who,of course need this-and ballistic missiles).
At now anyhow the problem is not-existing,for the reasons previously exposed.
 

sferrin

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voidmage said:
Ah-ah, oh no Spring, Re-entry speed of a MaRV today reach 12-13km/s-also much more-!!!!

Apparently you're unfamiliar with the term "escape velocity". ::)
 

voidmage

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I know perfectly the word AND the associated physics.But now,more than before, i am really interested in knowing the way in which you want to use THAT to defend your position.....Please,before launching yourself at 400 km/h against a steel pole,i recommend you to urgently check the path covering time of "basic" version DF-21 to its max range (2000 km in 12,3 minutes or MACH 8....). Please,please, REASON !!
 

sferrin

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voidmage said:
I know perfectly the word AND the associated physics.But now,more than before, i am really interested in knowing the way in which you want to use THAT to defend your position.....

Explain how a BALLISTIC missile traveling at greater than Earth's escape velocity is going to reenter the atmosphere.
 

voidmage

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You simply don't know balistic missiles functioning. A balistic missile don't cruise,it start with a boost phase(2-4 minutes for odiern ICBM missiles)with a asymptotic post-troposphere power decrease but speed gain(at about 7km/s for a ICBM),in this phase it lose majority of its fuel mass and enter low-Earth orbit (LEO)and stabilize itself in a suborbital elliptic orbit the apogee of which is directly proportional to distance to reach - probably you have thinked who the missile go over the atmosphere at so high speed and go lost in the outer space,i hope now it is more clear-;after it begin the second stage or midcourse phase where,following this “ballistic” traiectory it reach the aimed point ,then realign itself for coordinates collimation and start the third phase :the re-entry.
In my PC some years ago i have saved a link to a interesting scientific study on BM defences, at the beginning are the(simplified) equations of a typical bournout phase for this type of missiles: www.fas.org/rlg/garwin-aps.htm.
Now(at return from work)i have also searched for you on internet some link who can aid you to form a more complete picture of the speed question(but you can littelally find thousands of others!):
www.globalsecurity.org/wmd/systems/lgm-30_3-specs.htm (it give Minuteman III,who are much more slower than example R-36,burnout speed)
blog.wired.com/defense/2007/06/global_strike_p.html (i chosed this from the hundreds possibilities because it refere to a “likely” situation-attach to Theran from California-see the update part) you can deduce the “direct distance Los Angeles-Theran from this site : www.convertunits.com/distance/from/Los+Angeles,+CA/to/Tehran,+Iran (if you are curious the media speed –attention NOT the speed of re-entry...much ,much, much greater-is about 7,54 km/s or about MACH 22!!!)
Like you can see DF-21 is a slow missile also for a intermediate ballistic missile standards.I hope sincerely to be clear. Best regards.
 

flateric

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Guys, please watch your step. SPF is civilised place and it should be so always. You can offer your arguments in quite polite manner, *I know*. Let's go this way in future.
 

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flateric said:
Guys, please watch your step. SPF is civilised place and it should be so always. You can offer your arguments in quite polite manner, *I know*. Let's go this way in future.

I second this request!

Regards,

Greg
 

sferrin

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voidmage said:
You simply don't know balistic missiles functioning.

Apparently not. In this universe when something is space is going greater than escape velocity it doesn't come back down. What does it do in yours?
 

sferrin

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flateric said:
Guys, please watch your step. SPF is civilised place and it should be so always. You can offer your arguments in quite polite manner, *I know*. Let's go this way in future.

Watch my step? Is it too much to ask that someone explain one of their comments? I don't meant to be difficult but it doesn't seem impolite to question something that somebody says, particularly when it's so far detached from reality.
 

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for DF-21 the re-entry speed is only 3,7 km/s who is very low for today standard!!

What i'm saying is that such velocity can't be taken as the average (or "cruiser") speed, by reasons you already pointed out, yes it can be improved, everything can be, but i was talking about the normal rocket

I don't know what is the max. ceiling of the chinese missile, but the max ceiling has to do with the terminal speed, larger rockets (like ICBMs) have a higher ceiling, so their mirv re-entry velocity is higher

I don't understand the extensive explanation/debate about the escape velocity, meteorites fall into the atmosphere at higher velocities, they don't escape, because they are falling
 

sferrin

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Spring said:
What i'm saying is that such velocity can't be taken as the average (or "cruiser") speed, by reasons you already pointed out, yes it can be improved, everything can be, but i was talking about the normal rocket

I don't know what is the max. ceiling of the chinese missile, but the max ceiling has to do with the terminal speed, larger rockets (like ICBMs) have a higher ceiling, so their mirv re-entry velocity is higher

Typically RVs decelerate significantly during reentry (one of the safety mechanisms of many nuclear armed RVs even REQUIRE that in order to satisfy legitimate conditions for detonation).



Spring said:
I don't understand the extensive explanation/debate about the escape velocity, meteorites fall into the atmosphere at higher velocities, they don't escape, because they are falling

That's just it. If you're not aimed AT the earth and you're in space going escape velocity or better you will not come back down. That's what escape velocity MEANS. ;)
 

voidmage

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sferrin said:
voidmage said:
You simply don't know balistic missiles functioning.

Apparently not. In this universe when something is space is going greater than escape velocity it doesn't come back down. What does it do in yours?

sferrin i know who a speed of 3,5 km/s can appear very high,but it is absolutely insignificant in respect to escape velocity. At earth's level escape velocity is about 11,2 km/s or Mach 34 (it increase or diminish at second of direction of launch in respect to earth’ rotation)and this velocity ,of course,decrease as more a object move away from gravitational field of the planet(at example at apogee of a Minuteman III(1120 km) it is “only” 10,57 km/s, at 8500 km of distance from earth it would be 7,3 km/s).
DF-21 is not a ICBM ,it is a intermediate ballistic missile and ,among these, also a “slow” one. I hope sincerely who,now, the misunderstanding on the speed question was dissolved. Best regard
 

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voidmage said:
sferrin i know who a speed of 3,5 km/s can appear very high,but it is absolutely insignificant in respect to escape velocity.

If you'd read my post a little closer you'd see this was the bit in question:

"No i don't take ANYTHING! Let me understand...you think i have posted re-entry speed of DF-21? Ah-ah, oh no Spring, Re-entry speed of a MaRV today reach 12-13km/s-also much more-!!!! "

Which is entirely incorrect.
 

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sferrin said:
voidmage said:
sferrin i know who a speed of 3,5 km/s can appear very high,but it is absolutely insignificant in respect to escape velocity.

Maybe English isn't you're first language but if you'd read my post this was this bit in question:

"No i don't take ANYTHING! Let me understand...you think i have posted re-entry speed of DF-21? Ah-ah, oh no Spring, Re-entry speed of a MaRV today reach 12-13km/s-also much more-!!!! "

Which is entirely incorrect.

Yes, English is not my first language,but this statement (like "meteorites fall into the atmosphere at higher velocities, they don't escape, because they are falling") is true.
Re-entry vehicles can greatly accelerate while reposition its axis toward earth's gravitational field, ICBM builders simply,where this don’t hamper efficiency and operativity of the system,chose to don't do it for dodge enormous precision(CEP -Circular Error Probability-) and aerodynamic heating’s dispersion problems.
Today,not only MaRV but even spacecrafts,like return capsules with heat-sensible space "laboratory",satellites and experimental electronics systems,can exceed 11 km/s of re-entry speed (also if,for clear reasons,makers try where it is possibile,to avoid that),example: three years ago NASA’s Stardust has reached nearly 13 km/s http://www.businesswire.com/portal/site/home/permalink/?ndmViewId=news_view&newsId=20090223005140&newsLang=en, and the last year (2008) a russian one has reached about 14 km/s (13,8 )
I hope who, this time, all was clear. Best regards.
 

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Sorry my full naivety in field of ballistics, but wasn't Stardust recovering with such a speed due to its orbit parameters?
 

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flateric said:
Sorry my full naivety in field of ballistics, but wasn't Stardust recovering with such a speed due to its orbit parameters?

Yes flateric, also orbit parameters count, rather,for this type of spacecrafts,it is the discriminant function.
In fact,for a non military re-entry vehicle,accelerate toward earth's gravitational field, is not only pointless,but also dangerous.Nevertheless orbital elliptic trajectory's apogee is a decisive factor also in deciding ultimate speed of balistic missiles(in general,with a great simplification,we can say who the most far is the target ,the more "hight" is the apogee and,consequentely highter will be the final speed).
I want only to show who ,today,atmospheric re-entry with similar speeds involved are(also if rare)technically feasibles even for non military,"structurally" enormously more "sensitive"and frail systems. Best regards.
 

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flateric said:
Sorry my full naivety in field of ballistics, but wasn't Stardust recovering with such a speed due to its orbit parameters?

If you have a very elliptical orbit (that swings very low) you can get to a pretty high speed but not escape velocity. Now if you're orbiting around the SUN that is a different thing altogether as the numbers would be different. In short you cannot orbit around the Earth at greater than Earth's escape velocity.
 
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