Hi
@Shaheen missile
Lets delve into this issue of "maneuvering". First of all,there isnt any atmosphere to speak of above 60-70kms altitude.So RV wont exhibit any "aerodynamic maneuvering". Lets just for a second try to find out as to "why" we want a maneuvering warhead in the first place?.The reasons might include-
1)To evade interceptor
2)To confuse the tracking radar --I mean making the prediction of coordinates for firing solution more difficult.
3)To compensate for any gravitational anamolies RV faces while in elliptical free fall(after burnout point).
Lets start with #1:
Once the burnout point has been reached,and as RV crosses this point,it is traveling in an "elliptical" orbit--neither circular nor parabolic or what not.The kind of orbit is determined by the mission profile,range we want to cover etc etc.This orbit again is rendered by the angle at burnout and the speed at burnout.Both of them determine the apogee that a RV will attain--a higher apogee results in higher downrange.
Now if lets say,in some hypothetical universe shaheen or Agni-1/2 RV had active RF seeker,and they were able to detect the interceptor coming in itz path.It takes an evasive maneuver.This engagement roughly takes place when the RV has well past the apogee and is at altitudes of ~150km(still no atmosphere).Now you might ask,why is atmoshphere important? Well,as you might know control commands to RV is given in the form of short couples--to pitch and and yaw it--in order to change the trajectory.Now difference between performing this pitching and yawing in space and in atmosphere is what is known as "dynamic damping"--which is dependent on the effective area--in case of space you dont get any damping whereas in atmosphere there is dynamic damping. It is beautifully captured in the mathematical form by what are known as "damping derivatives". Ok now coming back to the topic,once the pitching and yawing command has been issued(at lets say 155kms) in order to evade the interceptor,the RV now is essentially falling on an altered ellipse(with changed eccentricity and semi-major axis)--and if it continues on this trajectory--it will surely miss the target.Now the only thing left to do is to come back to the original trajectory so as to not miss the target. These steps are incredibly complex as these have to be performed "before"-- mark the word "before" RV gets into atmosphere. What I am trying to say is the RV has got only 13-14 seconds(travelling at 18Machs) to come back on right trajectory so as to not miss the target. Because once the atmosphere starts,RV will have to encounter one more force and that is Aerodynamic forces! When you write force-balance equations, aerodynamic forces are absent in space and hence a neater differential eqn results.
You see,to implement all of what I have written above,you would essentially need a very very tight control system with latency figures in extremely tight tolerances. For god sake,you dont even know if shaheens or even ababeel uses a FOG or RLG based gyro.
My main intention here is to point out that changing trajectories in a matter of 13-14 seconds is extremely difficult if not downright impossible.And please just because US had this tech in 80s,doesnt mean pakistan or even India has it now.There are a lot of things that US have had since probably mid 60s that pakistan is nowhere close to getting--semi cryogenic engines being one of them!So,please get real!
@ghazi768
Hi,I gave out "scientific reasons" as to why one is superior to another.In case you want "proof" I would be much more happy to post plethora of literature here.But alas,I know research papers and patents are of no use to majority of pakistanis(barring a few exceptions) here. Now if you wish to refute it--as one gentleman above did with his "layman analysis",then kindly furnish "proofs".I hope you get what I am saying.
