What is the Terminal velocity of a Ballistic Missile Warhead? Mach 17 here.

[amardeep mishra]

https://www.rand.org/content/dam/rand/pubs/research_memoranda/2008/RM3475.pdf

The Ballistic coefficient is way different in this research paper ....
Far lesser than the value you are mentioning?

Kindly check the units associated with ballistic coefficients.American literature for some stupid reason still uses FPS unit instead of SI

 

[The Deterrent]

@amardeep mishra @HRK @The Deterrent and others interested

These calculations are not as straight forward as you want them to be. The RVs hit the atmosphere at about ~100km altitude, and from around 50-20km (depending on Beta coefficient) they decelerate rapidly till impact. The impact velocity of ~3000km class missiles is usually less than Mach 5.

Here is another good paper that will give you a better idea, as it considers Soveit IRBMs as targets for ABMs.
http://scienceandglobalsecurity.org/archive/sgs02lin.pdf

Now lets come to the point which you're probably trying to figure out; the interception capability of Indian PDV/AAD/S-400 interceptors against Shaheen series RVs, considering only the velocity as a variable. There are no definite answers to this, but in order for the Indian BMD to be successful:

1. The PDV exo-atmospheric interceptor should be able to intercept an RV having speeds up to Mach 15 at altitudes up to 120km.
2. The S-400's ABM should be able to intercept an RV having speeds up to Mach 12 (its stated capability is Mach 14) at altitudes up to 30km.
3. The AAD endo-atmospheric interceptor should be able to intercept an RV having speeds up to Mach 8 at altitudes up to 20km.

These figures are a bit more realistic assumptions of mine, so you are free to disagree.

@The Deterrent
Here is what I'm doing today--
View attachment 384737
View attachment 384736

A wireless router or radio T/R of your own, I assume?

 

[Safriz]

These calculations are not as straight forward as you want them to be. The RVs hit the atmosphere at about ~100km altitude, and from around 50-20km (depending on Beta coefficient) they decelerate rapidly till impact. The impact velocity of ~3000km class missiles is usually less than Mach 5.

Here is another good paper that will give you a better idea, as it considers Soveit IRBMs as targets for ABMs.
http://scienceandglobalsecurity.org/archive/sgs02lin.pdf

Now lets come to the point which you're probably trying to figure out; the interception capability of Indian PDV/AAD/S-400 interceptors against Shaheen series RVs, considering only the velocity as a variable. There are no definite answers to this, but in order for the Indian BMD to be successful:

1. The PDV exo-atmospheric interceptor should be able to intercept an RV having speeds up to Mach 15 at altitudes up to 120km.
2. The S-400's ABM should be able to intercept an RV having speeds up to Mach 12 (its stated capability is Mach 14) at altitudes up to 30km.
3. The AAD endo-atmospheric interceptor should be able to intercept an RV having speeds up to Mach 8 at altitudes up to 20km.

These figures are a bit more realistic assumptions of mine, so you are free to disagree.


A wireless router or radio T/R of your own, I assume?

I survey Naval structures,both damaged and under construction, so visual comparison of what's mathematically drawn on paper or CGI CAD is what i do.
Purpose of this thread was to make simple what is not simple ,
simple enough for everyone to understand...what is not simple.
I see 21-25 seconds for Russian Yars RV from reentry to impact in the first video. Even lesser for Minuteman 3 in the second video.
Thats the criteria i want to use , not mathematical calculations, as these are actual videos of actual tests.

 

[Taygibay]

as these are actual videos of actual tests.

And if released to the general public,
bereft of useful informations ...

just sayin', Tay.

 

[amardeep mishra]

These calculations are not as straight forward as you want them to be. The RVs hit the atmosphere at about ~100km altitude, and from around 50-20km (depending on Beta coefficient) they decelerate rapidly till impact. The impact velocity of ~3000km class missiles is usually less than Mach 5.

Here is another good paper that will give you a better idea, as it considers Soveit IRBMs as targets for ABMs.
http://scienceandglobalsecurity.org/archive/sgs02lin.pdf

Now lets come to the point which you're probably trying to figure out; the interception capability of Indian PDV/AAD/S-400 interceptors against Shaheen series RVs, considering only the velocity as a variable. There are no definite answers to this, but in order for the Indian BMD to be successful:

1. The PDV exo-atmospheric interceptor should be able to intercept an RV having speeds up to Mach 15 at altitudes up to 120km.
2. The S-400's ABM should be able to intercept an RV having speeds up to Mach 12 (its stated capability is Mach 14) at altitudes up to 30km.
3. The AAD endo-atmospheric interceptor should be able to intercept an RV having speeds up to Mach 8 at altitudes up to 20km.

These figures are a bit more realistic assumptions of mine, so you are free to disagree.


A wireless router or radio T/R of your own, I assume?

That's Intel centrino n135 wifi card for my Intel Galileo gen 2. I've got my own YouTube channel which I'd like to show you. Those two antennae are connected to the wifi card.

 

[Safriz]

@JamD any comments here?

 

[JamD]

@JamD any comments here?

Thank you for the tag. This isn't exactly my area of expertise so I would have to read up on all this domain knowledge. I'm sorry but busy these days. Amardeep has got the right idea. You would need to solve differential equations numerically. Photogrammometry on a video like that wouldn't be to useful in my opinion.

 

[Safriz]

And if released to the general public,
bereft of useful informations ...

just sayin', Tay.

well yeah they try to filter out any useful info but still much goes out into the wild if someone knows where to look.

 

[CriticalThought]

Sorry but books on signals and systems do not deal with differential equations describing kinematics of RV.for that you'd better need a good book on orbital mechanics or re entry dynamics.

You are right. But they still provide nuggets of information sometimes. Here is what I am referring to:

Book: Signals, Systems, and Transforms, 4th Edition
Author: Charles L. Phillips & John M. Parr
Sec: 2.6
Page: 61

We now discuss further the difference between a physical system and a model of that system. Suppose that we have a physical circuit with an inductor, a resistor, and some type of voltage source connected in series. Equation (2.53) may or may not be an accurate model for this physical system. Developing accurate models for physical systems can be one of the most difficult and time-consuming tasks for engineers. For example, the model that related the thrust from the engines to the attitude (pitch angle) of the Saturn V booster stage was a 27th-order differential equation.

 

[Yaseen1]

Pakistan should develop
hypersonic glide vehicle

 

[amardeep mishra]

Hi @CriticalThought
You wrote-
"For example, the model that related the thrust from the engines to the attitude (pitch angle) of the Saturn V booster stage was a 27th-order differential equation."
Well I am afraid you have not seen the guidance and control loop of any rocket,have you? Any such control loop has a lot of inner loops.It is way of implementing efficient control methodology.An inner loop generally speeds up the response of the outer loop.So,if lets say thrust happens to be one of the control variables in vector U belonging to R4,then pitch becomes one of the state variables.And a linearized relationship expressed in the form of laplace transform might add up to 27th order. This happens as I have explained above--various inner loops coming into play to make the control more effective.So an expression of the sort-
Pitch attitude(s)/Thrust(s) = f(s)/g(s)
Might very well turn out to be 27th order(as in the degree of g(s) to be 27).kindly note (s) represents laplace transform(only applicable to linearized system about an equilibrium point).
However if you care to look closely,our problem,as in problem raised by shaheen missile wasnt about "control",rather it was about finding the trajectory information(in forms of plots) of RV upon Re-entry. There is a HUGE DIFFERENCE between the two. So,the differential equations describing the kinematics of RV do not involve any control variables.Tbh,it is very very difficult to precisely guide any aerial vehicle in hypersonic regime.I wont go into the details of control(no matter how enticing it appears).
Non-Homogenous system is essence of control engineering.

 

[EndangeredSpecies]

@The Deterrent
Here is what I'm doing today--
View attachment 384737
View attachment 384736

Intel Galileo Gen 2 with a WiFi PCI-E daughter board. Making an IoT project or home SAN/video library?

Edit:
Oh got it, MQTT experiment. Interestingly, MQTT assumes a lossless ordered stream transport (http://docs.oasis-open.org/mqtt/mqt...3.1.1-errata01-os-complete.html#_Toc442180911).

This means some loss of realtime behaviour during communication, especially when there is a packet loss. Any idea why MQTT chooses such transport charecterstics over best-effort UDP?

Interestingly there is a MQTT-SN for sensors. Would it make sense if you use MQTT-SN for publishing data to your server. Will make it more realtime with a bit loss of data at times. Guess for Telemetry it would be better.

 

[Mrc]

missiles especially the latest ones are a generation ahead of their Pakistani counterparts

Any reason for that belief??
Caz in my mind this is making your whole post biased... as i firmly believe it may be other way around

 

[CriticalThought]

Hi @CriticalThought
You wrote-
"For example, the model that related the thrust from the engines to the attitude (pitch angle) of the Saturn V booster stage was a 27th-order differential equation."
Well I am afraid you have not seen the guidance and control loop of any rocket,have you? Any such control loop has a lot of inner loops.It is way of implementing efficient control methodology.An inner loop generally speeds up the response of the outer loop.So,if lets say thrust happens to be one of the control variables in vector U belonging to R4,then pitch becomes one of the state variables.And a linearized relationship expressed in the form of laplace transform might add up to 27th order. This happens as I have explained above--various inner loops coming into play to make the control more effective.So an expression of the sort-
Pitch attitude(s)/Thrust(s) = f(s)/g(s)
Might very well turn out to be 27th order(as in the degree of g(s) to be 27).kindly note (s) represents laplace transform(only applicable to linearized system about an equilibrium point).
However if you care to look closely,our problem,as in problem raised by shaheen missile wasnt about "control",rather it was about finding the trajectory information(in forms of plots) of RV upon Re-entry. There is a HUGE DIFFERENCE between the two. So,the differential equations describing the kinematics of RV do not involve any control variables.Tbh,it is very very difficult to precisely guide any aerial vehicle in hypersonic regime.I wont go into the details of control(no matter how enticing it appears).
Non-Homogenous system is essence of control engineering.

And you have missed my point completely. The point I was trying to drive across is given the complexity of the equations determining upward trajectory, it is highly dubious that simple triangulation can provide information about re-entry velocities.

 

[amardeep mishra]

Caz in my mind this is making your whole post biased... as i firmly believe it may be other way around

Hi @Mrc
Well no no, certainly not, I'm not biased.I'll give you reasons, it is for you to believe them.
The latest indian strategic missiles posses following technologies origin of which can be verifiably traced to indian labs, indian patents etc.
1)degree of Use of composite in indian missiles is far higher than their Pakistani counterparts making it light.For instance Agni 4 at just 17t can throw a payload of 1t to 4000kms!
2) Use of compact FOG and RLGs again designed and productionized by RCI Hyderabad.
3)Use of flex nozzle instead of either jet vanes or external control surfaces
4)canisterization
5) Abandoning the use of truss structure in between two stages.
6)Abandoning the use of any external control or stabilization surface.

Intel Galileo Gen 2 with a WiFi PCI-E daughter board. Making an IoT project or home SAN/video library?

Edit:
Oh got it, MQTT experiment. Interestingly, MQTT assumes a lossless ordered stream transport (http://docs.oasis-open.org/mqtt/mqt...3.1.1-errata01-os-complete.html#_Toc442180911).

This means some loss of realtime behaviour during communication, especially when there is a packet loss. Any idea why MQTT chooses such transport charecterstics over best-effort UDP?

Interestingly there is a MQTT-SN for sensors. Would it make sense if you use MQTT-SN for publishing data to your server. Will make it more realtime with a bit loss of data at times. Guess for Telemetry it would be better.

Hi!
I've never tried MQTT-SN,however at present MQTT gives me performance I'm looking at.My main objective is to code control algorithms into Intel Galileo gen 2