[ATTENTION!] Official article admits DF-21(X) has ability of attacking moving target

[JonAsad]

what is df-21(x) ? some sort of integration ?
or derivatives?

 

[dingyibvs]

The relevant part translates to: The DF-21 has improved continuously...blah blah...from hitting moving targets to slow-moving mobile targets, with precision increasing from CEP of several hundreds of meters to several tens of meters....

 

[JonAsad]

When ever i put the article in google translation it says sm thing like this.

This thing is sick.. This thing gona kick some A$$..

Whats the thing mate? Nyy 1

 

[GUNDAM]

No need to make that assumption yet. Am trying to make some headway with the Google translation. The guy wrote a lot but does not say much to explain how, even in the most general sense, does the DF-21 compensate for target dislocation and resistance to radar transmissions, if the warhead is so equipped. We are assuming the discussion is beyond the detection and ranging stage and on to when the warhead is on the descent. May be our Chinese members are willing to give an honest......translation better than Google can?

You complain about its "no how" because you are not familiar with Chinese official ways of talking about important weapon development.

An article written by a high level engineer or scientist about weapon development are always shown to be praising the dedication, team work or great leadership all the time. And this kind of article is just the final approve of an operational weapon system, more reliable than any military expert on the TV or network. And they won't expain any technique problem in this kind of article even the weapon is out of commission. Just to tell you, we have it.

Chinese official media can avoid to say "This is Su-27 in PLAAF" when broadcasting the Su-27 video for 10 years since Su-27 came to China, while even my 10-year-old nephew was asking me how to distinguish Su-27 from Russia and Chinese J-11, can you image this?

 

[ao333]

You complain about its "no how" because you are not familiar with Chinese official ways of talking about important weapon development.

An article written by a high level engineer or scientist about weapon development are always shown to be praising the dedication, team work or great leadership all the time. And this kind of article is just the final approve of an operational weapon system, more reliable than any military expert on the TV or network. And they won't expain any technique problem in this kind of article even the weapon is out of commission. Just to tell you, we have it.

Chinese official media can avoid to say "This is Su-27 in PLAAF" when broadcasting the Su-27 video for 10 years since Su-27 came to China, while even my 10-year-old nephew was asking me how to distinguish Su-27 from Russia and Chinese J-11, can you image this?

GUNDAM, you should paste and credit my friend's (ao333's friend) translation onto your post. Google translation does not suffice.

 

[GUNDAM]

but AC is not a slow moving target,i would rather wait for the Xinhua to confirm this news,even though i doubt they will ever do that,it's different from the GBI test that lots of countries can detecte the collision

Firstly, this article is from CASIC, where DF-21 was born, in a word, more authoritative than Xinhua. And Xinhua maybe never post it as the reason you know.

Secondly, the AC is fast in the sea, but for ballistic missiles, 33 knot is what called "Slow Moving" because it is even slower than some tanks and trucks. So do you think PLA setup a ballistic missile just to destroy a moving tractor?

 

[GUNDAM]

GUNDAM, you should paste and credit my friend's (ao333's friend) translation onto your post. Google translation does not suffice.

Sorry it is too long and I have not enough time.
Meanwhile, I think most parts of it won't interest our Pakistan friends because, you know, this is generally a "八股文" (no English word can fully express this word...)

 

[below_freezing]

hahahaha 八股文 这个词用得恰到好处~~~

 

[SXNJ]

这种官样文章看着就头疼，很多军迷喜欢在里面找寻蛛丝马迹

 

[Speeder 2]

This is getting juicy

you sound like a hardcorn **** star...

 

[GUNDAM]

what is df-21(x) ? some sort of integration ?
or derivatives?

The Anti-CV type must be one of DF-21B, C and D, but no clear and exact data can tell us which one is it, so I use (x).

I think, type C. No explanation.

 

[GUNDAM]

这种官样文章看着就头疼，很多军迷喜欢在里面找寻蛛丝马迹

That is because these articles are not for military fans or the public. Their purpose is to indicate Chinese military power to enemies in a very low key way.
You feel it dull and boring? No problem, it's not for you.
They just need to be understand by the enemy intelligence analyst.

 

[gambit]

That is because these articles are not for military fans or the public. Their purpose is to indicate Chinese military power to enemies in a very low key way.
You feel it dull and boring? No problem, it's not for you.
They just need to be understand by the enemy intelligence analyst.

As you wish...

I was expecting something a bit more 'scholarly' like:

===
The latest variant of the DF-21 has reaction thrust steering mechanisms. The radar system is high PRF X-band with a scan limit of 60deg. due to nosecone dimension. Since the target is moving, proportional navigation is employed to provide continuous target track. Despite the fact that the target is moving at only 33 knots, the PN guidance output is then converted to bang-bang guidance commands to provide the vehicle with near instant lateral acceleration to reduce interception probability by air defense missiles. Due to vehicle structural constraints, bang-bang guidance commands are limited to 10g. Standard fighter aircraft air to air missiles, because of their smaller warhead, can have bang-bang guidance forces up to 40g with no catastrophic structural failure.

Given the developmental maturity of ballistic defense missile system like the latest US SM-3, it is determined that the best execution altitude for vehicle deceleration for evasive maneuvers to be at 25 km above ground level (AGL). The longer the vehicle remains static, it will provide air defense radars with consistent vehicle profile and descent rate, also with the lower altitude, the higher air density would not allow the 20g evasive maneuvers, therefore the greater the odds of a successful interception. Further, this 10g bang-bang guidance limit is necessary to prevent the vehicle's radar system from losing target line-of-sight (LoS).

If this vehicle is used against fixed land targets that has air defense deployments, the vehicle can afford to lose target LoS with higher g-rating evasive maneuvers as target geo-coordinates are also fixed in memory. The vehicle will remember heading offset and deviation rate and can make appropriate return bang-bang guidance commands for the radar to reacquire target information. Against a moving target, even though one moving at only 33 knots, the current technology level does not afford the vehicle to lose a moving target LoS.

The latest US SM-3 missile is capable of reaching speed of 9600km/h with a climb rate of 5km/m in altitude, making early descent phase evasive maneuvers important to reduce interception probability. Missile against aircraft engagements typically occurs at or below 10km altitude, making feasible aerodynamic forces exploitation. But because this vehicle will begin to execute evasive maneuvers at very thin air altitude that reduces aerodynamic forces exploitation effectiveness, reaction thrust mechanisms are necessary and this will cost vehicle warhead payload.

During development, in post evasive maneuvers, an interface was thought to be required between bang-bang to proportional navigation guidance. Velocity compensated proportional navigation guidance (VCPN) was briefly tested as that interface and but was found to offer statistically negligible improvement in target tracking and guidance. Target lead angle and its rate change are nowhere as extreme as in a missile versus aircraft engagement and any vehicle descent rate change is already reflected in closing speed calculations. Therefore, it was decided to use only proportional and bang-bang navigation guidance methods.

Another developmental exploration was the order of guidance laws. The program decided to conduct dual testings. One strategy was bang-bang guidance for initial vehicle-target orientation, evasive maneuvers, then switches to PN guidance at 2km AGL. A parallel strategy has the reverse, PN for initial vehicle-target orientation and bang-bang guidance for evasive maneuvers. It was found that because bang-bang guidance is already sensitive to LoS change and rate of change, hardware related LoS noise can induce evasive maneuvers thrust command oscillations as the guidance laws attempt to null the LoS rate after every execution. This condition is similar to constantly oversteering an automobile, either due to driver ability or steering mechanism 'slop'. When PN guidance takes over at 2km AGL, the program recorded a higher miss rate than the pn_bang-bang strategy. In some instances, the vehicle's radar could not reacquire the target after several violent maneuvers to evade air defense missiles.
===

So even if just %50 of what I said above is true, what make you believe that we do not have a viable defense against the DF-21? Because the Chinese government said so...???

 

[GUNDAM]

As you wish...

I was expecting something a bit more 'scholarly' like:

===
.......
===

So even if just %50 of what I said above is true, what make you believe that we do not have a viable defense against the DF-21? Because the Chinese government said so...???

So this theory you mentioned here is not a new one: because radar limit, high-g limit, speed limit, ... the SAMs will have enough time and distance to destroy the warhead.
Well, no problem if every group of interceptors gets a good kill, and no problem if only 5 or 6 warhead are approaching.
But could this be realized?
I'm sure US NAVY can kill most warheads, but for DF21, 1 hit is enough, because its purpose is not to sink a CV but to give a big bang to the deck and stop the air strike.

 

[gambit]

So this theory you mentioned here is not a new one: because radar limit, high-g limit, speed limit, ... the SAMs will have enough time and distance to destroy the warhead.
Well, no problem if every group of interceptors gets a good kill, and no problem if only 5 or 6 warhead are approaching.
But could this be realized?
I'm sure US NAVY can kill most warheads, but for DF21, 1 hit is enough, because its purpose is not to sink a CV but to give a big bang to the deck and stop the air strike.

The issue here is the CONTENTS of the report that got all the Chinese fanboys going Lady Ga-Ga over. That report is mostly a rehash of the Chinese ballistic missile program. It does not say anything new about the DF-21 beyond what is already out there. What I posted came from me based upon my personal experience. That is what SHOULD be in order to earn credibility. I do not care if just half of what I posted is correct about the DF-21. That was not my intention. The lesson for you here is be more incredulous, even with what I posted. Just from using keywords search alone, you will learn far more from me than from Mr. Wang Ginben in his report regarding missiles.