Indian Missile News And Discussion

[ramana]

Time is coming to confirm the confidence in the delivered payload.

[Arun_S]

Thi sis th emost eye opening article in a long time.





[url="http://www.indiandefencereview.com/spotlights/the-inside-story-k-15/"]The inside story of SLBM K-15[/url]

By Cmde Ranjit B Rai Issue: Net Edition | Date : 11 Feb , 2013 On January 27, 2013 somewhere in the East Coast of India the 10.22-metre long K-15/B-05 solid-fuelled SLBM with a 750km-range and under water missile hit a predetermined target at sea successfully in a final trial from an underwater battery operated submarine like platform at about 20 meters depth. A Dr Chakravarty, a senior capable scientist of the DRDO who IDU learns from media has just been retired undecorated was delighted, and someone phoned Vice Admiral PC Bhasin to inform and congratulate him.



Bhasin was a former DG of the nuclear submarine INS ARIHANT/ATV project till few years ago as Secretary to the GOI. Bhasin was a former Chief of Material(COM) at NHQ and also Director of the ATV project who as a young Lt prepared the Styx Missiles for the Osa class boats used in the 1971 to hit ships off Karachi. All liquid fuelled missiles worked perfectly to Admiral Gorshkov’s delight. Bahsin has since lived missiles and electrics all his life as an electrical officer.



Media has reported that R & D had begun the project in 1998 by an Indian Navy-led team, since at that time the DRDO has only some 200 missile scientists & engineers, none of whom had any experience in developing solid-fuelled rockets.



Media has reported that R & D had begun the project in 1998 by an Indian Navy-led team, since at that time the DRDO has only some 200 missile scientists & engineers, none of whom had any experience in developing solid-fuelled rockets. Mark what media reported Indian Navy-led team as only NDTV Rep was allowed access to the Naval Ship where the DRDO scientists were on the naval tracking and look out ship.



It now comes out that Bhasin was wondering in 1997 why is the Indian Navy building a nuclear submarine for over Rs 3000 crores with a 300 km nuclear missile like Dhanush. Though electrical Bhasin, known as Indian Navy’s Rickover after the legendary US Admiral Rickover who headed US Navy’s nuclear submarine programmes for years, asked Navy and DRDO to think of a Solid fuel missile from under water with longer range as K Santhanam of DRDO was also thinking on same lines. . Bhasin took the risk allocated around Rs 300 crores and a Dr Chakraborty and his team now named by media began work at DRDL Hyderabad with freedom. This is the way projects should go.



Much is secret of the components but HILIFE Batteries Hyderabad had built submarine batteries but the Navy would not test them as Navy has strong bonds first with Standard Batteries who supplied the 200 ton batteries for submarines and later Exide who bought out Standard. HILIFE went to court against the Indian Navy on ‘competition law’ to make Navy buy its superior and cheaper batteries and in court revealed they were supplying DRDO submarine batteries for a project. Now one can link up it was the first name given to the underwater missile SAGARIKA ‘from the seas’, but it was classified. Inadvertently at Aero India when President Pranab Mukherjee as Defence Minister admitted to a journalists question that there was project called Sagarika. The name was changed to B-05 after Bhasin and many say it was named Bhasin and his birthday 5th, but the Scientists said it should be Kalam-15 as former President Kalam is born on 15th October 1931 so K-15. Now its name is K-15/B-05 in the media.



The R & D project, known as Sagarika, saw the development of various sub-systems of the K-15 that were tried out between 2004 & November 2008 in 10 different test-firings many in Bhasin’s time at various shore-based establishments off Balasore took place.. The first fully-integrated test-firing of the 6.5-tonne K-15/B-05 was conducted in January 2010 followed by another one in January 2011, another one in January 2012 & 27th Jan test-firing, in all totalling 4 test-firings of a fully functional SLBM from an underwater pontoon.



Two more test-firings are due in future, these being conducted from the Arihant SSBN sometime next year. The 27th Jan test-firing saw the K-15’s first-stage solid-fuel rocket booster being ignited inside a pontoon-based silo 20 metres under water & being lifted up to an altitude of 7km. Then the second-stage solid-fuel rocket ignited & lifted the K-15/B-05 to an altitude of 40km, following which the K-15 adopted a depressed trajectory flight-path. Being developed now is the follow-on 20-tonne 10.22-metre long but fatter K-4 SLBM which will have a 3,500km-range for the next ATVs with bigger plugs as increasing the range is now possible. This will be followed by an enhanced 12-metre-long version of the K-4 SLBM with a 5,000km-range. IDU congratulated Bhasin and Chakraborty and the unsung team and shows if Navy DRDO teams up with risk management sans bureaucracy more can be achived. In Navy we say BRAVO ZULU

This does tell the diameter of Arihant class is in excess of 13 meter.



The 20 tonne 10.22 m missile is being guessed as much less than 2.2 m (teh dia of teh tube). The 20 tonne mass with 3,500 km range is about right with physics of rocketry.



The 12 m long version will be definitely fatter 2 m or 2.2 m dia, and close to my prediction of Agni-3SL.

[Guest]

Arunji,



1. The Hindu reports that A-6 will be a 65-70 ton class missile with a range of 6000 km for 4-6 warheads. Is this because we are restricted to boosted fission weapons of the sloika type (each MIRV weighing about 500 kg or so for a yield of approx. 150 kt ) ?



2. Did we ever test any boosted weapon of the sloika kind ? Was S-2 (not S-1 primary) of this type as well ?



3. You say that our sloika types of 150-250 kt yield do not weigh 1-ton. Then, what is the 1-ton payload likely to be ? A larger weapon of similar design with higher yield (say 300-500 kt) ?



4. Given that NoKo has tested now (appears they got about 20 kt though news reports play it down to say 6-7 kt), they may have the equivalent of the S-1 primary in their possession. What do you think ?

[Arun_S]

[quote name='Kritavarma' date='13 February 2013 - 05:03 PM' timestamp='1360754752' post='116472']

Arunji,



1. The Hindu reports that A-6 will be a 65-70 ton class missile with a range of 6000 km for 4-6 warheads. Is this because we are restricted to boosted fission weapons of the sloika type (each MIRV weighing about 500 kg or so for a yield of approx. 150 kt ) ?[/quote]

This is the big 'danda' (full range ICBM that other major countries posses) that stabilizes Indian deterrence of punitive retaliation on any country full 360 degrees. While A3 can deliver a single warhead (of limited potency) at full range, A5 can deliver a single warhead of greater potency to full range. A6 of 65 tonne will rain decoy and brahmastra that even a determined enemy with ABM will find it very challenging.

[quote name='Kritavarma']

2. Did we ever test any boosted weapon of the sloika kind ? Was S-2 (not S-1 primary) of this type as well ?[/quote]

Field test - no.

Other - humm.... credible enough alternative .... ?!



[quote name='Kritavarma']

3. You say that our sloika types of 150-250 kt yield do not weigh 1-ton. Then, what is the 1-ton payload likely to be ? A larger weapon of similar design with higher yield (say 300-500 kt) ?[/quote]

Weapon with different level of confidence (certainty) level (and possibly different yield).



[quote name='Kritavarma']4. Given that NoKo has tested now (appears they got about 20 kt though news reports play it down to say 6-7 kt), they may have the equivalent of the S-1 primary in their possession. What do you think ? [/quote]

The previous N test was no simple fission test, but was boosted primary for use in 2 stage TN. NoKo and Pakistan are jointed at the hip in this endevour. Poof goes Indian nuclear warhead qualitative edge against Pakistan.

All N7 nations know that but are keeping quite.

[Guest]

Arunji,



What other credible enough alternative would be there to field testing ? Some kind of laser fusion facility ? But if this gives credibility, why not two stage TNs themselves ?



Bharat Karnad says that a number of in service warheads are untested staged TNs based on a corrected version of RCs fizzle. He says that they come in yields of 125-175 kt.



Still, I feel that the sooner they test again, the better. No real losses in testing, barring some superficial sanctions. On the other hand, vast gains come from field testing: parity with the PRC/TSP/NoKo axis on the warhead quality front, demonstration of political will power before the world (itself important for deterrence), etc...

[Arun_S]

Arihant can't carry warheads based on Pok-1 Pok-II, due to harmful radiation to men in close quarter.



So either Arihant idles, or Pok-III happens.

[Guest]

[quote name='Arun_S' date='26 February 2013 - 01:49 AM' timestamp='1361864507' post='116495']

Arihant can't carry warheads based on Pok-1 Pok-II, due to harmful radiation to men in close quarter.



So either Arihant idles, or Pok-III happens.

[/quote]



What prevents them from putting untested new warheads on Arihant ? after all, if most of our sloika type weapons are also not field tested but still have undergone some other ``credible" alternative, what prevents HEU based sloikas from undergoing the same alternative you mentioned without actually undergoing field testing ?



Also, if what BK states about 2 stage TNs being deployed (without field tests) after corrections made to RCs fizzle are true, then I would not put it beyond the establishment to deploy untested TNs specially meant for SLBMs. Adm. Arun Prakash hints at such a phenomenon when he mentions in one of his articles that absent further testing, the yield of SLBM warheads will be uncertain. Some in the establishment who for whatever reason may be hesitant to test may be satisfied deploying warheads of such uncertain yield.



I hope, however that this is not the case and that Pok-III happens no matter who in power does it..

[sayareakd]

[Arun_S]

Earlier news reports have thouroughly confused armchair warriors, with speculation of a reusable bomber that carried bombs and comes back.



DRDO has said it is like and better than the unkill tomahawak (THK). It can drop many bomb-lets each weighing few kgs on its way just like THK, doesn't mean it is meant to fly back in which case it be called a UAV or UCAV. Unlike THK however Nirbhay can fearlessly hover around kill zone waiting to choose and engage the target (s) at a time and preferred attitude of engagement (I.e. azimuth of engagement). Better than tomahawk, its engine inlets are recessed thus RCS is really very tiny (compared to THK or its likes) even from frontal perspective. Side perspective RCS is even tinier.



From the available picture one can see the center-of-gravity of the craft as flies the 1000 km (location of wing hing).



IMHO DRDO has done a V good job at the design. Good test.



One can only imagine the smarts of teh system. Navigation is expected to be very accurate thanks to recent advances we have seen in other flying vehicles. DRDO report points to intelligence to do target acquisition late in the game, meaning its tip has range of optical/multispectral/hyperspectral sensors, sensor fusion and more importantly classification, recognition and prioritization of target field. They may start with simpler algorithm, and then graduate to the bleeding edge (if only they choose the person who has the know-how in teh country).

[rosstaylor2440]

These missiles are the great achievement for the India, also thanks from for the providing information about 'Dhanush' anti-ship capability missile . It has payload capacity 500kg. and also having capability to hit the target in the range of 350 km

[osman]

Looks like Agni VI or Agni VII as the case maybe is MIRV/MARV 3 tonne, 6000KM ICBM. The how to get there on Agni VII or Agni VI is also spelt out. Agni V uses a metallic first stage motor. They are planning to use a 40 tonne composite motor. It sort of clears the air on why all stages were Composite. I suppose the composite first stage did not include composite motors. Therefore the final missile hopes to gain a lot of tonnage/range by doing this final step. The largest such motor for Agni VI or Agni VII. It's not sure Agni VI will be the monster. Chander in a recent NDTV? walking in the lawn interview stated that he has not decided what the mirv/marv missile will be called. (Agni V+ or Agni VI or Agni VII), similar to the Agni II+ to Agni IV 1.1 meter counterforce singe warhead missile. Agni V being the counter value MIRV ready missile or a bigger counter value single warhead equivalent.



Given it's one of his last interviews, he seems to have laid out the final interviews with a defiant: We are close to a Trident II kind of goodbye. I read we are close as 6 to 7 years away, with the landmobile MIRV icbm around 3 to 4 years away.(He says "eventually" Agni VI/VII will be 13 meters in length and 2 meters in dia.) The number of Agni Vtests has gone up from the stated 3 earlier to five in this interview. Hints for the cleaver. Eventually this missile will morph into our final credible deterrent undersea. AKA, this is Surya II and the underwater equivalent will be based on this misslie. Agni V was Surya I.





Based on the earlier projections on enrichment capabilities and the reported 12 nuclear submarines India is interested in it looks like 4 x 4 x 8 dial-able HEU encased nukes is what India wants fielded in the next decade. Arihant might just be experimental and the one after that too. There seems to be a relaxed approach to what we need and there seems to be a plan on howto get there. 2020 might be the target date on the fissile materials and 2025 is more likely the delayed deployment. Of course none of this answers the fissile vs sizzle debate. Would we invest in a 3 tonne 6000km ICBM with MIRV if we did not think we had minaturized nukes or are pretty close to minaturized thermonukes with a couple of tests? It could also be a problem of confidence levels of the thermonukes if and when we need them. Assuming it was a sizzle, it might not be a bad idea to test them when the situation gets out of hand for us(provided they don't spin off too fast). Not ideal, but I guess the best we can hope for now. Either way, these are very determined steps and possibly the genie is out there and there is nothing much to cap and roll back ... I think the Americans and the Europeans have seen the writing on the wall with the Agni V test ... and china to a limited extent ...



Well I think I will stop following the ballistic missile tests for a while... It seems like there isn't much to this space in India except for implementing the designs and hoping things go to plan. The end message seems to be Given Agni V was modular with the largest composite motor so far in India. Agni VI/VII is just a bigger composite motor and additional design changes away ... An engineering challenge, but no longer a technological leap, with most of the technologies firmly under our grasp ... The political will is another question, but so far it seems a lot of governments have had the will ...





Advanced Agni-6 missile with multiple warheads likely by 2017





By Ajai Shukla

Business Standard, 8th May 13



Ending worldwide speculation about the futuristic Agni-6 missile, the Defence R&D Organisation (DRDO) has briefed Business Standard about the direction of India’s ballistic missile development programme after the Agni-5 enters service, probably in 2015.



DRDO chief Dr VK Saraswat, and missile programme chief Dr Avinash Chander, say the Agni-6 project has not been formally sanctioned. However, the missile’s specifications and capabilities have been decided and development is proceeding apace. Once the ongoing Agni-5 programme concludes flight-testing, the defence ministry (MoD) will formally okay the Agni-6 programme and allocate funding.



Chander says the Agni-6 will carry a massive three-tonne warhead, thrice the weight of the one-tonne warhead that Agni missiles have carried so far. This will allow each Agni-6 missile to launch several nuclear warheads --- Multiple Independently Targetable Re-entry Warheads (MIRVs) --- with each warhead striking a different target. Each warhead --- called Maneuverable Reentry Vehicle (MARV) --- performs evasive maneuvers while hurtling down towards its target, confusing enemy air defence missiles that are trying to destroy them mid-air.



The DRDO is at an advanced stage of developing these warhead technologies. But the difficult challenge is building a booster rocket that can propel a three-tonne payload to targets 5000 kilometres away. This weighs almost as much as the satellite payload carried by the Indian Space Research Organisation’s much larger and heavier Global Satellite Launch Vehicle (GSLV).



“Our ballistic missiles must be compact and road mobile, even the Agni-6 with its heavy payload. We will do this by building the first stage with composites, fitting the Agni-6 with India’s first composite 40-tonne rocket motor. This is a technical challenge but we have good capability in lightweight composites,” says Chander.



The road mobile Agni-6 would also have stringent limits on its length. “It must be carried on a standard size trailer that can move from one part of the country to another, turn on our roads, cross our bridges and climb our heights. As the payload weight increases, we will require more advanced technologies to keep the missile’s length constant,” explains Chander.



Coaxing higher performance from smaller rockets becomes especially important in submarine launched ballistic missiles (SLBMs), which can be no longer than 13 metres so that they can fit into the cramped confines of a submarine. Even long-range SLBMs that can fly 14,000 kilometres, like the Chinese JL-2, are built no longer than 13 metres. The DRDO faces this challenge as it develops the K-4 SLBM for the country’s Arihant-class nuclear-propelled ballistic missile submarines (SSBNs).



Eventually the Agni-6 will be no taller than the Agni-5, i.e. about 17 metres, says Chander. It will, however, be heavier and thicker --- slightly over 2 metres --- which will cater for the different shape of the MIRV payload.



“The timeframe for developing a new missile system is about 5 years and the DRDO has mostly achieved this in the Agni programme,” says Chander. Calculating five years from April 2012, when the Agni-5 had its debut launch, the first test of the Agni-6 could happen in 2017.



The DRDO says the Agni-6 will have a longer range than the 5000-kilometre Agni-5, but is not mentioning figures. “The MARVs and MIRVs will give us extended range. I will not be able to tell you how much because that is secret,” Saraswat told Business Standard.



Ballistic calculations, however, suggest that at least some of the MIRV warheads on the Agni-6 would reach at least 6,000 kilometres. In a missile that travels 5,000 kilometres, the last MIRV warhead released flies an extra 1,000 kilometres.



Currently, the DRDO is readying for the second test next month of the Agni-5 Intermediate Range Ballistic Missile (IRBM). This will be fired in the same configuration as its debut test a year ago, in order to establish the missile’s reliability. A third test by end-2013 will see the missile fired from a canister.



“We will conduct at least 5-6 more Agni-5 tests before the missile enters operational service. After the repeat test this month or the next, we will conduct two test firings from a canister. Then the military units that will operate the Agni-5 will conduct 2-3 test firings as part of the induction process. Even after induction, the users conduct test firings as part of the Strategic Forces Command (SFC) training plan,” says Avinash Chander.



The Agni-5 is a three-stage, solid-fuel missile but its first stage consists of a metallic rocket motor, while the second and third stages have composite motors.

[Arun_S]

I am having the last laugh on some fools who were outraged/incredulous at my articles on Agni series with variants carrying MIRV, both for land based systems and submarine based Agni missiles.



Agni with MIRV was called by some idiot as my imagination and my frustration with BARC was for not delivering a weapon design that can be MIRVed ; that India will never need MIRV and BARC was never required to provide light weight high yield (I.e. TN) warheads.



R Chidumbram doomed Indian nuclear deterrence. The shameless moron still lives his miserable life glued to his chair (SA to PM) to cover up fizzle hole he dug for India.



India had to suffer a lot to work around and clean up the Sh*t he created, and settle with deterrence options that befit a second-rate power.



The untested "patched" up TN design will never fully populate Indian MIRV missiles, at best they will be mixed (interleaved) with heavier FBF based warhead to carry a semblance of assurance warhead yield to nations that need be deterred.



The "patched" up TN design is anyway not applicable as useful warhead for Arihant submarines. Unless the navy readies sacrificial crew to die of radiation sickness due to proximity with warheads.

[shyam1]

India to use geo-stationery satellites for missile defence

Manoj K Das, TNN | May 19, 2013, 04.41 AM IST

http://timesofindia.indiatimes.com/indi ... 130007.cms?

Quote:

KOCHI: India has launched an ambitious programme to use its array of geo-stationary satellites (G-sats) to monitor missile activities in an area of 6,000 km. With this, the country's constellation of G-sats will become the first line of defence in its anti-missile shield. This programme is independent of the observation grid installed by defence and intelligence agencies. The advantage of using geo-stationary satellites is their fixed position at a height of 36,000 km and synchronised with the earth's movement.



Allaying fears that this deployment could compromise India's space policy, sources clarified that it is not meant as an offensive posture and data won't be shared with any other country. "We're using these satellites to warn us of an impending danger even as they continue with their primary tasks of transmission and meteorological observations," sources said.



A top source told TOI that special lens and processing electronics are being developed to significantly improve the power of G-sat cameras and telescope. "The Centre has given ISRO the go-ahead. The programme is into a crucial development phase,'' he said.



The project is aimed at installing sensitive surveillance equipment along with other payload on the G-sats. "They will capture the signature of any missile launch activities happening in a radius of 6,000 km.This signature will be transmitted to a central control unit which would initiate necessary counter-mechanism," sources said.



The Defence Research Development Organisation (DRDO) is developing the interceptor missile which has entered trial phase. "Given their strategic position, we can even have exclusive facility to monitor a country or a particular region. Given the G-sat's capability to map anything to a resolution of one metre, we will be able to capture the slightest of movements or even heat signatures,'' sources said.

[sayareakd]

two interesting pics







and this







K15 underwater launch and platform pic.

[osman]

[quote name='sayare' date='10 June 2013 - 09:03 PM' timestamp='1370877907' post='116674']

two interesting pics







and this







K15 underwater launch and platform pic.

[/quote]



https://www.youtube.com/watch?v=KQUgFz4QWKc





A couple of observations based on these images and the video from which these images are extracted.



The blue drum of the underwater launch rig is possibly 1.5 to 1.75 meters high. The hatch cover of the launch rig is almost twice the size of the blue drum. Therefore the outer diameter of the hatch door looks like it's approximately 3 to 3.5 meters. The inner k5 silo seems to be slightly smaller. Seems to confirm Arun's numbers of 2 to 2.2 meters with maybe a little clearance.



If you notice the outer hatch cover has five sensors horizontally and an additional five sensors vertically. These are placed on the diameter of the hatch cover. 3 to 3.5 meter hatch cover has six such divisions including the outer end where there are no sensors(two of these). So the spacing between the sensors is half a meter to 0.6 meters. The diameter of the missile launched form the the launch rig captured in the image is 1.5 to 1.8 meters. Which indicates it could be a test launch consistant with the reports of a k05(?). Also the sensors seems to be positioned to verify the exact position at launch of the missile along the x-y axis on launch to identify any deviation of the misslie on canister launch (?) You will notice the down bubble on the whole rig and the missile more to the left when it leaves the launch tube. The sensors on the right are left exposed (This assumes the camera is set to always show the plumb line position using gyros which are common on RC aircraft for stabilization and fairly easy to get hold of for mounting ...). Additionally, you can also make out the diameter of the missile launch cap under water is 1 to 1.2 meters. This cap is then jettisoned on launch in the video after it climbs a few meters above the sea surface(?). So this missile test was for a ek phool wala misslie(?).



The questions I am mulling over is: Does a down bubble launch require more silo clearance than a vertical launch (?) to prevent the missile trying to correct itself on launch to align with the waters natural buoyancy forces? Maybe this force has to be overcome in a submarine launch and hence the high thrust launch from the canister at approximately 30m/s(?). Maybe this is why the initial tests were of a smaller diameter missile with progressive launches being performed with lower clearance. Get comfortable with launches of 1.5 to 1.8 meter missiles before pushing the envelope on the silo clearance(?).





Additionally from the video the 10.2 meter missile launch seems to traverse the 3 to 3.5 meter launch hatch completely in a second or so. The last frame is cut off so I am not very sure this is true. The launch velocity is 25 m/s to 30m/s(? my arithmetic skills aren't great ) Of course the missile after clearing the surface is ignited and has a different launch velocity when the rockets power up.



Additionally at 3.53 in the video the mockup shows 4 missiles in each silo (?) So that's sixteen per submarine? Interesting. 4 silos or launch tubes.



Disclaimer: Take all of my calculations with a pinch of salt. I have a tendency to mess up on arithmetic by making some really unforced errors in silly places.

[osman]

Additionally thats 4 launch tubes x 4 missiles x 9 submarines = 144 nukes without MIRV. Some of the later subs will likely be hunter killers. So India is building both kinds of subs or maybe all three kinds. They want 12 nuclear submarines ... with 3 out of commission or on backup patrols thats 9 subs. I would assume we will use 4 subs for the ballistic role and the rest will be special ops and hunter-killer roles. Well all of this assumes we have four misslies per silo as shown in the figure. With MIRV the numbers will change dramatically. Maybe we won't need four missiles per silo. One misslie will be enough per silo ... Interesting choices ... But then again who knows ... It's all guess work ...



This seems to favor arun_s point of view on the fizzile debate and the corrected bums being not MIRV-able in submarines atm ... or it could also be the first stage before MIRV after a few more nuclear tests ... Unkil is bound to test his nukes in the next decade or so. I think that's when we test on their tail.

[osman]

@Ramana,



I used this terminal velocity calculator to get some approximate answers to your question. Might be way way off the mark.



http://www.calctool.org/CALC/eng/aerospace/terminal



Terminal velocity of A1 is approximately 244 m/s for a cross section of 1 meters, weight of 500kg and a drag coefficient of 0.1.



Terminal velocity of A1 is approximately 345 m/s for a cross section of 1 meters, weight of 1 ton and a drag coefficient of 0.1.



The last frame of the fuse being tested on A1 enteres the frame at 1.26 explodes at 1.27 and a part of the entry vehicle seems to touch the sea at 1.29 or 1.30.



So the fuse seems to be blown at 345 x 2 or 244 x 2 = 488 m to 690m



If the cs of the reentry vehicle is smaller the terminal velocity could be higher at 550 m/s which makes the fuse at 1000 meters high. It will change according to the warhead design but Agni I seems to be housing the 15kt fission warheads for deterrence against Pakistan or at least that seems to be the fuze tested. If the fuze tested was TN the reduced cross section would have increased the height to 1000 or 1100 meters.



Please feel free to point out any errors in the calculations. I don't have rocketsim or similar packages. I am a bit short on time now. Will read up some more on derivation from the first principles some other time to confirm these numbers using basic physics of ballistic missiles.

[osman]

http://4.bp.blogspot.com/-aRQgOKv2NYY/UQ...issile.jpg



Sub launched missile cap separation.

[ramana]

So its about 1500 to 2100 feet.



My guess was 500 to 1000 feet. maybe its more draggy.



You think its radar sensing or some other thing?



BTW whats the beta in lbs units?

[osman]

[quote name='ramana' date='20 June 2013 - 01:25 AM' timestamp='1371671227' post='116685']

So its about 1500 to 2100 feet.



My guess was 500 to 1000 feet. maybe its more draggy.



You think its radar sensing or some other thing?



BTW whats the beta in lbs units?

[/quote]



I didn't get the beta question. By beta are you referring to coefficient of drag or angle of attack? I have discounted the angle of attack in the calculations as the warhead is like a bullet or at worst conical and cross sectional area won't vary too much between the different angles of attack.



Some quick numbers. I haven't used fluid dynamics in a while (ten years). From memory Cd is dimensionless. Cd of a warhead in my opinion is that of a streamlined cone or bullet or even better. This is done to reduce the drag and keep the reynolds number down. Reynolds number(above 10^5) if it increases too much leads to turbulence and flow separation. While engineering the flow the warhead should produce laminar flow as opposed to turbulent flow even at high velocity ranges. cd of 0.1 might be way too much its probably more streamlined. A cone has a cd of 0.5. A bullet has a cd of 0.3. A cd of 0.5 will most likely lead to turbulent flow (Will have to look up reynolds number equations to be sure).



115 to 161 m/s for a cd of 0.5 1 ton to 500kg warhead.



150 to 210 m/s for a cd of 0.3 1ton to 500kg warhead.



The fuze could be triggered by measurements from the accelerometer in the warhead on reaching the right terminal velocity. There are mil grade accelerometers in small packages. I don't know if they have a gyroscope as well for orientation. The non BGRV, MARV, ones are pretty dumb and may not have the gyroscopes. We recently had the system on chip news for the INS. These might enable our warheads to carry an INS if they are sufficiently small. (This is purely speculation though).



Let me see if I can find some of my old fluid dynamics text books to verify these numbers this weekend.