Exactly my thought. Sure hope they “stress tested” it in 50 deg C and not -50 deg C which has hardly any bearing on us.Karan M wrote:Yeah, ask these guys how many of these systems were stress tested in the conditions we face in the plains, in the Thar etc.
Anyhow, some addition to our capabilities. Best not crib.
Quite so, with the introduction of the S400 and NASAMS for the NCR, the Indian airspace would probably be one of the best-defended airspaces in the world., the best of the East meets the best of the west !., probably no other nation would field such a diverse variety of equipment. A potential adversary would . have a headache just thinking about the defences, that said the whole conundrum needs to be integrated to a national grid with input to space command as well., that will give the ABM/SAM systems antisatellite capability as well., better bang for the buck. An ABM firing should include simultaneous launch of anti sat weapons that can knock out of the adversaries satellites, both GPS and comm sats as well. A doctrine in effect to this will serve to contain Chinese assistance to Pakistan as well unless they want to risk their beidou s as well.nam wrote:Our BMD (PDV & AAD) should take the path of S400/S500.
Need to get MRSAM/ XRSAM, a version of QRSAM and PDV/AAD under all integrated Swordfish and mobile search & tracking AESA radars.
All should be one single package, to form the layered defense.
By the way we are spending close to 10 billion on SAM. Despite people crying over falling sqd numbers, the SAM investment is tremendous.
There were some reports of IAF testing R-77-1, RVV-BD (R-37 I think) from Sukohi a couple of months ago. One can assume some sort of DDM in the above report...if at all buying Russian AAMs, hopefully they will be buying the updated ones.In the wake of Balakot, and the Pakistani Air Force's attempts to hit targets in India, foiled by Wing Commander Abhinandan Varthaman and his colleagues, the Indian Air Force (IAF) has begun looking for new armaments for its fighters.
* For any air force, it is not only about a high-quality fighter, but also, armaments, and in this age, missiles fired from beyond visual range (BVR). Wing Commander Varthaman had fired a short-range Russian R-73 missile at the Pakistan Air Force F-16 on February 27 this year. The IAF has just signed a contract for about 400 R-73s missiles worth around Rs 1,000 crore. The IAF sees the heat-seeking R-73 (with a range of about 30 km) as a low-cost, high-efficiency solution as it can be fired from many of its fighter jets, including the newer MiG-21 Bison, the MiG-29 and the Sukhoi-30MKI.
* India has also asked Russia for more X-31 Anti Radiation Missiles (ARM). These can be fitted on to most Russian designed fighters like the Sukhoi or the MiG-29 and even the French-made Mirage-2000 and are very accurate. These are supersonic air-to-surface missiles and the IAF will get about 250 of them (at a cost of about Rs 1,800 crore) and are effective against radar stations. The IAF had got some ARMs from Russia earlier.
* The IAF is also getting the very sophisticated Russian BVV-AE air to air missiles. These are roughly equivalent of the US-made AMRAAM missiles that were fired by Pakistani F-16 fighters on February 27. The BVVs have BVR capability with a range of about 80 to 100 km. About 400 of them are likely to be purchased and can be fitted on to the MiG-21 Bison, the MiG-29 and the Sukhoi-30.
The purchases come in the wake of Balakot, after which the Defence Ministry gave the armed forces emergency powers to make up for shortages in weapons and ammunition. The IAF is also procuring other weapons and equipment to maintain operational readiness. This is also another sign that India continues to buy weapons from Russia despite strong international pressure.
NAG-fire & forget anti tank missile uses imaging infrared seeker in lock-on-before-launch mode.The robust imaging algorithm has made the missile hit the target even in severe summer desert conditions which is unique in its class
OK here is the link.ramana wrote:In statistics there is a concept called rank sample tables. It gives you probability number at different confidence levels. So Nag getting 10 hits out of 10 trials gives a probability number at 50% and 95 % confidence. What are those numbers?
SSridhar wrote:During Aero India 2019, DRDO announced that Nag was finally set to enter production by the end of 2019 after undergoing the final set of summer user trials in May-June, 2019. From the above MoD tweet, it appears that Nag has cleared all trials finally. Hopefully !
रक्षा मंत्री कार्यालय/ RMO India
·
Jul 19
All missiles met the mission objectives including minimum and maximum ranges, direct attack as well as top attack modes and achieved a direct hit onto the target. NAG ATGM has been developed by DRDO to engage highly fortified enemy tanks in all weather conditions
@DRDO_India
रक्षा मंत्री कार्यालय/ RMO India
·
Jul 19
Raksha Mantri Shri
@rajnathsingh
has congratulated the user evaluation teams from Indian Army and
@DRDO_India
on NAG’s successful completion of user trials.
Supersonic Missile Assisted Release of Torpedo (SMART): DRDO has taken up a project to develop and demonstrate a missile assisted release of light weight anti-submarine torpedo system for ASW operations far beyond torpedo range (50-650 km). During August, 2018, pneumatic ejection test of TAL dummy torpedo from canister was carried out at 150 bar which established the design of safe shear pin failure. Ejection speed of torpedo was also estimated during the trials.
A typo.nam wrote:https://mod.gov.in/sites/default/files/MoDAR2018.pdf
I hope I understood it correctly.
SFDR is been developed for impluse of 1200 Sec! that is 20 minutes of flight! Claimed range is 340KM.
Now 20 mnts of flight at Mach 3 gives ... 1000KM+ range! Even if not that range, it can keep chasing the target for 20 minutes!
Ya Allah, What am i missing?
Unless someone can correct my understanding of impulse.srin wrote:^^^ I don't understand the confusion, saar.
Specific impulse of rocket is around 200s, so the SFDR is much much more efficient. Interestingly, the ramjet's specific impulse is around 800 (per wiki), so the SFDR is more efficient than a ramjet (something that I hadn't thought of).
The range is factor of both the specific impulse and how much fuel/oxidiser is carried, no ? I honestly didn't get the calculation you presented above.
nam wrote:Unless someone can correct my understanding of impulse.srin wrote:^^^ I don't understand the confusion, saar.
Specific impulse of rocket is around 200s, so the SFDR is much much more efficient. Interestingly, the ramjet's specific impulse is around 800 (per wiki), so the SFDR is more efficient than a ramjet (something that I hadn't thought of).
The range is factor of both the specific impulse and how much fuel/oxidiser is carried, no ? I honestly didn't get the calculation you presented above.
SFDR missile is suppose to achieve 1200 sec impulse. It means the fuel + aerodynamics allows it a flight time of 1200 sec. Calculating a straight line theoretical range of travelling at Mach 3 for 20 minutes, gives a range more than 1000 KM!
It is also claimed SFDR is ranged to be 340KM. Even if I consider practical constraints, 1200 sec, should give us more than 340KM range.
So either 1200 sec impulse is wrong or we are understating the range... by a lot.
Does any one believe a Mach 3 missile flying for full 20 minutes, will reach only 340KM?
It is clearly mentioned as Specific impulse which is measure of how effectively a rocket uses propellant and not the flight time, srin has explained the sameMoDAR2018 wrote: boron based sustainer to deliver specific impulse of 1000 - 1200 sec in ramjet
From the wiki link:Kakarat wrote:It is clearly mentioned as Specific impulse which is measure of how effectively a rocket uses propellant and not the flight time, srin has explained the sameMoDAR2018 wrote: boron based sustainer to deliver specific impulse of 1000 - 1200 sec in ramjet
Your understanding is wrong please correct it
Isn't that fundamentally flight time or part of flight time? Granted we don't know at what Mach speed is the 1200 sec defined, however being a Ramjet, it has to be more than Mach 1, before the engine kicks in.The curious unit of seconds to measure the 'goodness' of a fuel/engine combination can be thought of as "How many seconds this propellant can accelerate its own initial mass at 1 gee".[9] The more seconds it can accelerate its own mass, the more delta-V it delivers to the whole system.
Specific impulse is a measure of how efficiently the propellant is used not for how long the motor is working .SFDR missile is suppose to achieve 1200 sec impulse. It means the fuel + aerodynamics allows it a flight time of 1200 sec.
nam first thing Specific impulse is for a engine not for the entire rocket, but seriously I don't know how to make you understandnam wrote:From the wiki link:Kakarat wrote:
It is clearly mentioned as Specific impulse which is measure of how effectively a rocket uses propellant and not the flight time, srin has explained the same
Your understanding is wrong please correct it
Isn't that fundamentally flight time or part of flight time? Granted we don't know at what Mach speed is the 1200 sec defined, however being a Ramjet, it has to be more than Mach 1, before the engine kicks in.The curious unit of seconds to measure the 'goodness' of a fuel/engine combination can be thought of as "How many seconds this propellant can accelerate its own initial mass at 1 gee".[9] The more seconds it can accelerate its own mass, the more delta-V it delivers to the whole system.
I am thinking it is Mach 1, because 1200 sec flight gives around 350KM range!
I will be happy be corrected, if some one can tell why would seconds be used as unit to depict efficiency, other than to indicate the duration of thrust/power provided by the engine for a standard mass of fuel.
Specific impulse is for propellant and engine by virtue, what does it have to do with range .. unless you think of only the "engine" blasting off to somewhere, i guess when you talk about range of a rocket/missile its more about quantity of fuel it carries and the velocity the engine can achieve plus burn time that is directly proportional to both !Kakarat wrote:nam first thing Specific impulse is for a engine not for the entire rocket, but seriously I don't know how to make you understandnam wrote:
From the wiki link:
Isn't that fundamentally flight time or part of flight time? Granted we don't know at what Mach speed is the 1200 sec defined, however being a Ramjet, it has to be more than Mach 1, before the engine kicks in.
I am thinking it is Mach 1, because 1200 sec flight gives around 350KM range!
I will be happy be corrected, if some one can tell why would seconds be used as unit to depict efficiency, other than to indicate the duration of thrust/power provided by the engine for a standard mass of fuel.
The Specific impulse of CE-20 is 443 does it mean that it flies for 443 seconds? It actually flies for 643 seconds. Specific impulse is a measure of engine efficiency and flight duration depends on available fuel and other factors
Its not so much as 'more efficient fuel utilization', but simply having fuel with more energy density and the fact that its air-breathing propulsion (unlike solid rocket motors, DR motors don't have to carry oxidizing agent on-board). Boron is pretty much the highest energy density (by volume) material (considering only chemical energy and not nuclear reaction based energy).Katare wrote:1200S is pretty impressive, best a rocket can achieve is with Liquid H2 @ 550 seconds. Solid rockets max out just above 200seconds, Jet engines can achieve up-to 3-4000 seconds.
So going from ~200 S to 1200S is 6x more efficient fuel utilization. Since there will be additional dead weight, controls etc that will eat into much of the gains but still one can expect 2x the range of a similar solid rocket missile
Is it true that DR motors don't have an oxidizing agent ? My understanding was that there will be a fuel rich (ie, with lesser oxidizer than in normal rocket) which feeds the exhaust gases into the ramjet (where it then burns completely due to atmospheric oxygen).JayS wrote:Its not so much as 'more efficient fuel utilization', but simply having fuel with more energy density and the fact that its air-breathing propulsion (unlike solid rocket motors, DR motors don't have to carry oxidizing agent on-board). Boron is pretty much the highest energy density (by volume) material (considering only chemical energy and not nuclear reaction based energy).Katare wrote:1200S is pretty impressive, best a rocket can achieve is with Liquid H2 @ 550 seconds. Solid rockets max out just above 200seconds, Jet engines can achieve up-to 3-4000 seconds.
So going from ~200 S to 1200S is 6x more efficient fuel utilization. Since there will be additional dead weight, controls etc that will eat into much of the gains but still one can expect 2x the range of a similar solid rocket missile
Can I suggest a small amendment ....Katare wrote:Jay,
This is a side discussion but specific impulse is a unit of efficiency of fuel utilization in a propulsion system. .....
Nothing beats air breathing engines since they don’t carry oxidizer or at least not all of it. So that is the rocket propulsion 101 that I know. .
.Nothing chemical beats air br ...for specific impulse
When you say "6x more efficient fuel utilization" it suggests some different way of burning the fuel vis-à-vis solid rockets. In fact exact same fuel as the solid rocket motor can be used in DR and they would burn in pretty much the same way i.e. chemical reaction. The difference factors are presence of Boron and Air-breathing. Just wanted to point that out.Katare wrote:Jay,
This is a side discussion but specific impulse is a unit of efficiency of fuel utilization in a propulsion system. We know that H2 being the smallest molecule achieves the highest efficiency and releases highest chemical energy in oxidation chemistry while there are some crazy fluoride based chemistries (I don’t know about boron but may be possible) that are marginally better than H2 but they are not worth the trouble of enhanced EHS concerns.
Nothing beats air breathing engines since they don’t carry oxidizer or at least not all of it. So that is the rocket propulsion 101 that I know.
For same fuel and over all rocket weight a ducted motor would produce a much longer impulse or carry the same weight a lot longer distance.
India needs to take a lesson from this and make MMRCA award conditional on the winner having to share the source codes and complete readiness to integrate third party missiles and armaments on the platform.Indrajit wrote:The Economic Times · 5 hours ago
India, Russia sign Rs 1,500 crore deal for air-to-air missiles to be used by Su-30.
https://www.google.com/url?sa=t&source= ... nm&cf=1
Of all R-27!