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PostPosted: 14 Apr 2015 06:54 
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Folks please pardon me for staring yet another thread - but I think this sort of issue is important for the future of the nation. We need to see results, not announcments. We have seen hundreds of targets set for the LCA all of which have not been met. Some senior offcier says "LCA SP xx will fly in April 20xx" and it never happens. if it does not happen why did the officer say that? was he lying? if he was noy lying why does he not say what the matter is? or else shut the fuk up and do not announce a date.

I start with what I see as one big DRDO bluff, the hypersonic vehicle
nash wrote:
Hypersonic Technology Demonstrator
Vehicle (HSTDV)
: DRDO is developing
HSTDV having speed up to 6.2 Mach.
Successful ground test of full scale scramjet
combustor carried out with gaseous ethylene
fuel for 20 sec in connect pipe mode
test facility. Fuel could ignite at extreme
combustor entry Mach number of 2.7.
Combustor performance meets the mission
requirement in terms of thrust generation.
Prototype of cruise vehicle bulkheads has
been realized. Flight hardware of inter-stage
has also been realized for launch vehicle.

I am sick of hearing about this. DRDO needs to demonstrate that they are not taking the country for a ride. In 1996 or 1998 Aero India the entire DRDO display was dominated by a model of this hypersonic vehicle. 20 years down there is virtually no progress. DRDO is bluffing and we are getting hoodwinked. They are achieving nothing in this regard.

I will post an image ( a video grab) of that Hypersonic vehicle model from 20 years ago

Guess what ISRO has done in this same last 20 years?


Last edited by shiv on 14 Apr 2015 11:39, edited 1 time in total.

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PostPosted: 14 Apr 2015 07:00 
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To me the following report sounds like a bluff designed to make us think that something is ahppening. the language used is the exact meaning of Double speak - i.e vague nonspecific things that lead up to meaning nothing. Just read this travesty
Quote:
Canon Launched Guided Missile (CLGM):
CLGM is the semi active laser homing antitank
missile which is able to engage the enemy
tanks up to 5 km. The kill mechanism with
CLGM is tandem high explosive anti-tank
warhead. Instrumented flight trials from tripod
have been successfully completed and midcourse
guidance has been demonstrated.
Instrumented flight trials from tripod? What the hell does that mean. Did they fly a tripod at 800 meters per sec to simulate an artillery shell?


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PostPosted: 14 Apr 2015 07:01 
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What was the last LCA deadline announced by some big shot at HAL?


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PostPosted: 14 Apr 2015 07:03 
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shiv wrote:
To me the following report sounds like a bluff designed to make us think that something is ahppening. the language used is the exact meaning of Double speak - i.e vague nonspecific things that lead up to meaning nothing. Just read this travesty
Quote:
Canon Launched Guided Missile (CLGM):
CLGM is the semi active laser homing antitank
missile which is able to engage the enemy
tanks up to 5 km. The kill mechanism with
CLGM is tandem high explosive anti-tank
warhead. Instrumented flight trials from tripod
have been successfully completed and midcourse
guidance has been demonstrated.
Instrumented flight trials from tripod? What the hell does that mean. Did they fly a tripod at 800 meters per sec to simulate an artillery shell?


Umm.. because it was launched from a tripod ?
Image


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PostPosted: 14 Apr 2015 07:13 
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Thakur_B wrote:
Umm.. because it was launched from a tripod ?
Image

LOL thanks.

But that is exactly what I call doublespeak. We already have missiles whose guidance and electronics work after the stresses of launch. I do not have figures at my fingertips but I expect missile launches probably put the electronics through maybe 15 or 20G acceleration.

But a cannon accelerates a shell from zero to 1000 meters per second over a distance of about 4 meters (my guesstimate). How do you launch a cannon shell from a tripod? I am no ballistics whiz but that looks like 125,000 G to me unless I am mistaken. Will that guidance system work after being shot out of a cannon?


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PostPosted: 14 Apr 2015 07:20 
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shiv wrote:
Thakur_B wrote:
Umm.. because it was launched from a tripod ?
Image

LOL thanks.

But that is exactly what I call doublespeak. We already have missiles whose guidance and electronics work after the stresses of launch. I do not have figures at my fingertips but I expect missile launches probably put the electronics through maybe 15 or 20G acceleration.

But a cannon accelerates a shell from zero to 1000 meters per second over a distance of about 4 meters (my guesstimate). How do you launch a cannon shell from a tripod? I am no ballistics whiz but that looks like 125,000 G to me unless I am mistaken. Will that guidance system work after being shot out of a cannon?


I think you are confusing the launch mechanism. It is not a tank shell, it is just a missile that launches from a tank cannon.


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PostPosted: 14 Apr 2015 07:30 
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Thakur_B wrote:
I think you are confusing the launch mechanism. It is not a tank shell, it is just a missile that launches from a tank cannon.

It is entirely possible that I am mistaken. So you are saying that this is like a canister launch of a missile where the missile is ejected from the barrel and the motor ignites after ejection? Fair enough - I can accept that.


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PostPosted: 14 Apr 2015 07:32 
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shiv wrote:
Thakur_B wrote:
I think you are confusing the launch mechanism. It is not a tank shell, it is just a missile that launches from a tank cannon.

It is entirely possible that I am mistaken. So you are saying that this is like a canister launch of a missile where the missile is ejected from the barrel and the motor ignites after ejection? Fair enough - I can accept that.


The missile ignites inside the canon, there is no other propellant to push the missile out.


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PostPosted: 14 Apr 2015 07:34 
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Steps in conventional missile design
- draw up requirements: target, launch platform weight, *ities etc 2-3 years
- create paper design using cad whatnot 1-2 years
Design phase complete
- build prototype, instrument it and launch from stand 1-2 years if tools and fixtures are concurrent
- fine tune as design is never perfect 1-3 years
Begin test phase
- launch instrumented version from platform of choice 1 year
- launch with payload 1 year

Demonstration phase complete

- repeat usually over 40 times to get performance over a variety of ranges and targets. 4-5 years
Production evaluation
~40 times gets you to normal Gauss distribution.

HSDTV will take a long time even in advanced countries.

Time frame 2050.

India is in top five in that area.


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PostPosted: 14 Apr 2015 07:40 
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The timeline issue is a very important one because it has been mentioned as one of the issues that the IAF has.

The forces, (and foreign vendors in general) are very specific about timelines. As we have ourselves seen about HAL and DRDO projects on BRF timelines are always exceeded by unpredictable periods.

I used to be very sympathetic to DRDO saying that technology cannot be restricted to timelines. But honesty demands that no time lines must be given if they cannot stick to a specific timeline. I find it preposterous that the DRDO and PSU heads - all people with comfy jobs and fat salaries cannot say things that are any different from the coconut harvester guy who tells you that he will come "tomorrow" and turn up after 3 weeks


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PostPosted: 14 Apr 2015 08:17 
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IAF wants a fully developed weapon system as soon as they find a requirement.

Anywhere else they do wargames and come up with requirements and develop concepts which turn into demonstration evaluation phase to finally production and induction.

Sometimes process can be compressed but leads to glitches which could be terminal.

I don't know about why timelines are not met.
Usual reasons : over reach, under-estimation of tasks. Underfunding to get the job sanctioned. "Nanda Raja Bhavishyathe!":will see when we have to cross the bridge.

Usual fix is more reviews and deep dives.

Also services have to be more engaged in the process of development and production.


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PostPosted: 14 Apr 2015 08:25 
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ramana wrote:
IAF wants a fully developed weapon system as soon as they find a requirement.

Anywhere else they do wargames and come up with requirements and develop concepts which turn into demonstration evaluation phase to finally production and induction.

Sometimes process can be compressed but leads to glitches which could be terminal.

I don't know about why timelines are not met.
Usual reasons : over reach, under-estimation of tasks. Underfunding to get the job sanctioned. "Nanda Raja Bhavishyathe!":will see when we have to cross the bridge.

Usual fix is more reviews and deep dives.

Also services have to be more engaged in the process of development and production.


Perfectly reasonable - but I would love to expose the rotten people in the system and the rotten departments of the past that have damaged the country. Of there there are good people and uncertainties. But the rot in PSU and the blindness or unreasonableness of IAF need separate exposure and documentation


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PostPosted: 14 Apr 2015 08:33 
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ramana wrote:
HSDTV will take a long time even in advanced countries.

Time frame 2050.

India is in top five in that area.

Of course

But here is my question.
1. I quote from the report above
Quote:
Successful ground test of full scale scramjet combustor carried out with gaseous ethylene fuel for 20 sec in connect pipe mode test facility. Fuel could ignite at extreme combustor entry Mach number of 2.7. Combustor performance meets the mission requirement in terms of thrust generation. Prototype of cruise vehicle bulkheads has been realized. Flight hardware of inter-stage has also been realized for launch vehicle.

2. I recall reading that one gliding test of this vehicle has been conducted (I would be happy if someone can confirm this)

But we are now 20 years down the line. In 20 years we have done 1 gliding test and one test burn of combustor? This is looking like a low profile project that goes on and on and on allowing a small bunch of people to join DRDO and retire while the project gets a trickle of funds for DRDO bragging rights. Is there no time limit for funding or creation of a product?

Heck private parties are launching satellites and near space vehicles. Where is this program heading?


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PostPosted: 14 Apr 2015 08:48 
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Hakim,

You will appreciate the developments (and the lack of it) when you see the presentations at AI'15 seminar. There are some really nice talks on the state of art challenges we face and have overcome, not just in India, but human knowledge in this flight regime as a whole. By the way, this project is driven by DRDO, but there are a lot of profs from around the country working on this. Seems like the Australians are doing quite well because they experiment much more, while we have been developing theories. I can assure you, it will be time well spent.


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PostPosted: 14 Apr 2015 08:53 
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shiv, The report you quoted is about the engine. It ges very hot and even 20 sec burn time is good with fuel injected while at Mach 2.7
To me it looks like they have a solid booster that kicks it to Ma2.7 and then the combustor takes over.


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PostPosted: 14 Apr 2015 09:17 
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indranilroy wrote:
Hakim,

You will appreciate the developments (and the lack of it) when you see the presentations at AI'15 seminar.

Sorry to be cynical - but I have been exposed to Aero India seminars or reports from them from the first edition of Aero India in 1996. You probably know that I am the only guy who has videos up on YouTube from that show.

It was in one of those videos that I have filmed the DRDO stall with the Hypersonic vehicle dominating. I was, 20 years ago, as hopeful as anyone could be. I am sure one of the engineers who spoke to me at the the DRDO stall in 1996 must be either out of DRDO, working in America or senior management in DRDO by now.

Without meaning to be patronizing I would like to point out that a boy who was in 10th std in 1996 could now be a BRFite in his mid thirties. I was in my thirties back in the 90s. Everything is moving on - except the project which appears to be moving on by periodic updates. Imagine a department that has run for over 20 years, with things moving at a relaxed pace, with no deadline other than the need to provide periodic updates and make Power Point presentations. Power Point did not exist in 1996 and it has increased the power of departments that are required to do very little over a huge timespan with no deadlines visible to us.

In 1996, there was a mock up of Nag. For 20 years we BRFites agonized over Nag and MMR etc. But it has moved forward in 20 years. Mind you it is still not inducted but "it has moved". So yes the Hypersonic vehicle "has moved" in 20 years. But how far? And how much more? No one is going to tell you that.


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PostPosted: 14 Apr 2015 09:19 
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ramana wrote:
shiv, The report you quoted is about the engine. It ges very hot and even 20 sec burn time is good with fuel injected while at Mach 2.7
To me it looks like they have a solid booster that kicks it to Ma2.7 and then the combustor takes over.

Ramana - I should not be asking you this question - so it is not directed specifically at you and obviously I will not hold you responsible for the answer. But exactly what is it about this engine that took 20 years to achieve? I want to be proud. I want to praise our folks.


Last edited by shiv on 14 Apr 2015 09:26, edited 1 time in total.

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PostPosted: 14 Apr 2015 09:25 
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Since this appears to be an ungli thread, Shiv, I would suggest you call in Rajat Pandit and Shiv Aroor to help you out further.

I agree we should shut down this DRDO, and whichever PSU you please.

What is your alternative to making product roadmaps? Your suggestion will be revolutionizing any product development world over!
fwiw, and you might not want to deal with real world data on this thread, but 67% of projects fail to meet their deadlines. Must be DRDP/PSU project managers running the show in private organizations world over. But you are right. Of course.


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PostPosted: 14 Apr 2015 09:32 
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DexterM wrote:
Since this appears to be an ungli thread, Shiv, I would suggest you call in Rajat Pandit and Shiv Aroor to help you out further.

I don't need their help. Where spaces exist for unglis. unglis will be inserted.

I have been at the forefront of praising and supporting DRDO and I still do in places that you do not see. If you feel taqleef, I ask you to answer questions if you have answers. It is in the very places that answers don't exist that there are holes for unglis - and speaking of holes for unglis - I have been a supporter of INSAS and OFB products.

But the morons at OFB, in reaction to the Delhi rape have produced a revolver for women made of Titanium alloy called "Nirbheek" which costs Rs 200,000 - which is more than the annual earnings of 80% of all Indians (and 99% of Indian women). Exactly what were the morons at OFB thinking when they made that?

Is that an answerable question or a hole for an ungli?


Last edited by shiv on 14 Apr 2015 09:43, edited 1 time in total.

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PostPosted: 14 Apr 2015 09:36 
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DexterM wrote:
I agree we should shut down this DRDO, and whichever PSU you please.

What is your alternative to making product roadmaps? Your suggestion will be revolutionizing any product development world over!
fwiw, and you might not want to deal with real world data on this thread, but 67% of projects fail to meet their deadlines. Must be DRDP/PSU project managers running the show in private organizations world over. But you are right. Of course.

Ah so this is the edited message "added later"

I did not say shut down DRDO. That is a strawman you are creating

What is my roadmap?

My roadmap is to rip a new one where it needs ripping so that anyone who reads the thread knows that a younger generation is aware that good things and bad things are happening and that the bad things will, hopefully, be tolerated less and less.


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PostPosted: 14 Apr 2015 09:47 
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shiv wrote:
ramana wrote:
shiv, The report you quoted is about the engine. It ges very hot and even 20 sec burn time is good with fuel injected while at Mach 2.7
To me it looks like they have a solid booster that kicks it to Ma2.7 and then the combustor takes over.

Ramana - I should not be asking you this question - so it is not directed specifically at you and obviously I will not hold you responsible for the answer. But exactly what is it about this engine that took 20 years to achieve? I want to be proud. I want to praise our folks.


I would point out that hypersonic flight is not simple stuff. It's a major problem in metallurgy just to keep the darn thing from melting in on itself. If you want it easy then do the ram jet/scram jet thing and I would point to the Bhramos missile as a huge success story. But please, don't jump on absolutely bleeding edge, world class technology as an example of squander. It's tough, I mean really tough to step out into the void and go before all others.

And before you go there, yes, the US is also doing this bleeding research and we haven't made a whole lot of progress. We do have some interesting data though. Whoopee. But we will grunt it out eventually, stubbornly spending gazillions and making lots of mistakes. It's what we specialize in.

Here is a prime example. (and we will overcome this)

http://www.adn.com/article/20140825/arm ... nch-kodiak

Sorry to bother you.


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PostPosted: 14 Apr 2015 10:07 
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I recall reading a quite a detailed article from DRDO on the state of the high Mach number research in India. The article was presented by someone from DRDO in Australia.
All I can remember from that are
- pictures of test equipment being used and being developed.
- with high Mach numbers fluid flow , there are intense shock waves and interference shock waves
- fluid inside cannot be treated as gas.
- something about sustaining the fuel flame or some such.

To me it looked like just getting to design the !test! !equipment! itself is a multi-year project.


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PostPosted: 14 Apr 2015 10:16 
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shiv wrote:
DexterM wrote:
I agree we should shut down this DRDO, and whichever PSU you please.

What is your alternative to making product roadmaps? Your suggestion will be revolutionizing any product development world over!
fwiw, and you might not want to deal with real world data on this thread, but 67% of projects fail to meet their deadlines. Must be DRDP/PSU project managers running the show in private organizations world over. But you are right. Of course.

Ah so this is the edited message "added later"

I did not say shut down DRDO. That is a strawman you are creating

What is my roadmap?

My roadmap is to rip a new one where it needs ripping so that anyone who reads the thread knows that a younger generation is aware that good things and bad things are happening and that the bad things will, hopefully, be tolerated less and less.


Just how will stop any research team that is looking for funds from making grand promises? You do understand the constraints we impose on our folks.
If you want to approach the problem with the intent for a solution - look for the root causes. (And one of those does include Self-Aggrandizing political leaders within research labs - this is undeniable). But to ascribe it to the entire organization is not ripping a new one - it is merely ranting without outcome. After all these years, if you wish to expend your intellectual capital on a rant, that is your choice. But like you demand the right to rip a new one, we demand the right to a solution from you!

There is no single problem afflicting every research lab out there. Academics here will attest to their own funding constraints. Product managers who rely on labs for real world solutions will also attest to the failure of the lab rats to provide anything on time (read, to capture market share/make more money/give me a quick raise to CMO and so on). What you really want us to do is to list the reasons for failure. Please pick the same projects and RCA them. If at all these inefficient labs are doing the same, they would already have implemented the lessons learned for everything other than the promotion-grabbing announcements.

But if you ascribe negative connotations to something as simple as vendor failure (read this as Cobham), you are on the wrong path and we need to tell you as much!


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PostPosted: 14 Apr 2015 10:19 
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Neela wrote:
I recall reading a quite a detailed article from DRDO on the state of the high Mach number research in India. The article was presented by someone from DRDO in Australia.
All I can remember from that are
- pictures of test equipment being used and being developed.
- with high Mach numbers fluid flow , there are intense shock waves and interference shock waves
- fluid inside cannot be treated as gas.
- something about sustaining the fuel flame or some such.

To me it looked like just getting to design the !test! !equipment! itself is a multi-year project.


I am hoping there are spinoffs from this that I don't know about. Velcro and nonstick cookware as spinoffs of the US space program is piffling thing compared to the cost input - but it is tomtommed till every school child knows. If this research program has spinoffs in data and equipment that can help other programs like missiles or propellants or metallurgy for aircraft engine blades fine. But surely DRDO should mention at least one possible spinoff. So far they have stuck to the original story of around the world in 4 hours and reusable sat launch vehicle. It strikes me that ISRO should know something about shock waves and hypersonics and high temperature resistant materials. Is there a firewall between ISRO and DRDO because of the feared "sanctions" word?


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PostPosted: 14 Apr 2015 10:26 
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DexterM wrote:

Just how will stop any research team that is looking for funds from making grand promises? You do understand the constraints we impose on our folks.
If you want to approach the problem with the intent for a solution - look for the root causes. (And one of those does include Self-Aggrandizing political leaders within research labs - this is undeniable). But to ascribe it to the entire organization is not ripping a new one - it is merely ranting without outcome. After all these years, if you wish to expend your intellectual capital on a rant, that is your choice. But like you demand the right to rip a new one, we demand the right to a solution from you!

There is no single problem afflicting every research lab out there. Academics here will attest to their own funding constraints. Product managers who rely on labs for real world solutions will also attest to the failure of the lab rats to provide anything on time (read, to capture market share/make more money/give me a quick raise to CMO and so on). What you really want us to do is to list the reasons for failure. Please pick the same projects and RCA them. If at all these inefficient labs are doing the same, they would already have implemented the lessons learned for everything other than the promotion-grabbing announcements.

But if you ascribe negative connotations to something as simple as vendor failure (read this as Cobham), you are on the wrong path and we need to tell you as much!


That is a fair argument. But how I approach this topic is my business. Thanks for indicating how you think I should approach it.

I have picked on two projects to diss for the time being - the "Hypersonic vehicle" and the "cannon launched missile" and I have some useful replies and information. I intend to argue out any weak argument and shut up when i am wrong and the answer is adequate - such as Thakur's reply about cannon launched missile.

I will in due course come up with other projects that I fell like ripping a new one for and hopefully will get some excellent replies as have been provided so far.


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PostPosted: 14 Apr 2015 10:27 
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Since I have worked on Hypersonic vehicle Physics in past (not HSTDV but the one which ISRO is developing), I think I have some idea of the stuff. I would consider myself lucky if I could see practical hypersonic plane flying before I die (missiles with scramjet technology might come a little sooner than that). And I do have at least 40-50 yrs of life left still (hopefully :mrgreen: ). And I am quite hopeful that India will be among the creators of the first hypersonic plane, whenever it happens.

I agree what Indranil has mentioned few posts ago. We don't seem to be doing enough experimental stuff, both due to lack of facilities and funds and because it doesn't seem to be of particular priority.


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PostPosted: 14 Apr 2015 10:29 
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have to say the SR71 designed by a lean team and fairly small budget in 1960s is a true miracle for the tools and knowledge base of that era. its peers were the sabrejet and F-104 types. the combined turbojet + annular ramjet at higher speed....very non-linear A++ thinking level, the materials used, the space suits for the pilots, dealing with the leaking fuel, thermal management. probably these all were all first timer problems encountered.


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PostPosted: 14 Apr 2015 11:40 
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Thread title modified to a less provocative one


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PostPosted: 14 Apr 2015 11:53 
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Singha wrote:
have to say the SR71 designed by a lean team and fairly small budget in 1960s is a true miracle for the tools and knowledge base of that era. its peers were the sabrejet and F-104 types. the combined turbojet + annular ramjet at higher speed....very non-linear A++ thinking level, the materials used, the space suits for the pilots, dealing with the leaking fuel, thermal management. probably these all were all first timer problems encountered.




IIRC, the fuel leaked only on the ground. in flight, at higher airframe temperatures, the leaks sealed up on their own due to expansion


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PostPosted: 14 Apr 2015 18:11 
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It is one thing to have a heat shield on a nose cone or a manned capsule upon atmospheric re-entry. It is quite another thing to slam hot plasma gases through an engine and still have a working engine afterwards.


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PostPosted: 14 Apr 2015 18:38 
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Quote:
have to say the SR71 designed by a lean team and fairly small budget in 1960s is a true miracle for the tools and knowledge base of that era. its peers were the sabrejet and F-104 types. the combined turbojet + annular ramjet at higher speed....very non-linear A++ thinking level, the materials used, the space suits for the pilots, dealing with the leaking fuel, thermal management. probably these all were all first timer problems encountered.


Fuel leak was calculated down to the number of drips and they wrote acceptable limits into the SOP's. Kelly was once asked by a young engineer on what could be done to stop the drips, and he put a cash reward for anyone in the company that could solve the issue because he did not think it to be relevant operationally. The prize was never claimed throughout the life of the aircraft.

The biggest issue was the Titanium and machining it, and they had multiple design iterations. First they tried to run this thing on Liquid Hydrogen, and that did not go well for them ;) before it was dropped. The A-12 was the 12th iteration so they tried quite a bit. I may not remember exactly but i read somewhere that there were as many patents filed for the manufacturing process as were for the design features and components.

When Kelly originally designed the SR-71, his roadmap envisioned speeds all the way up to Mach 4 as the design matured as he thought that this would be required to keep the thing relevant over its entire 30+ year life. The maximum speed claimed is mach 3.4 by the lockheed test pilot but that was heat limited. Of course with the SR, it was as much about top speed as it was about sustaining Mach 3.2 (thats the speed where the sensors worked their best) for prolonged periods at altitude. Who knows what the skunks did that is not known to us as till this many aspects of the design program (In addition to the operational, and development of the oxcart and SR programs) are not openly discussed (and may even be classified). Interestingly when they were testing the RATTLRS in one of their briefings the lockheed employee said that we have testing data for this concept till mach 4 before he shut up and changed topic. There used to be a video of that somewhere on the internet, i'll try to find it.


Last edited by brar_w on 14 Apr 2015 18:40, edited 1 time in total.

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PostPosted: 14 Apr 2015 18:40 
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Shiv, I understand your frustration at non-completion of projects by DRDO( others too but this thread is about the DRDO/OFB and Indian PSU military industrial complex). And we should discuss them. Not cuss them.

In the annual MOD reports on DRDO they write about a high powered committee that meets to review all the projects going on and so far haven't seen them cut off funding or terminating the projects.

Funding is a big problem. If trickle funding is given to do paper studies but not to experiment or build anything, it hurts the projects many ways. Also there is a penchant to announce that India is at the cutting edge of many technologies when all that is being done is paper study. E.g.. LCA proposal was first made in 1984! That date is stuck in peoples minds. In a R&D you need all kinds: big thinkers who can conceptualize big goals, seat of the pants experimentalists who implement the ideas and hardworking technologists who can make it production worthy reliable weapons system.

An aside: DRDO promotes the big thinkers who get access to politicians. All the famous DRDO chiefs are that category. As goes the chief so goes the band.


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PostPosted: 14 Apr 2015 19:02 
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ramana wrote:

Funding is a big problem. If trickle funding is given to do paper studies but not to experiment or build anything, it hurts the projects many ways. Also there is a penchant to announce that India is at the cutting edge of many technologies when all that is being done is paper study.

Too true. But "survival" is like asymmetric warfare - meaning "that which is being discouraged from surviving manages to survive in a small niche where it cannot grow, but just survives."

What I mean is - if there is poor funding for a particular project and not much attention being paid then an incumbent head may retire or resign. The department attracts little attention until one incompetent whom no one wants is pushed in there to do his thing.

I am not saying that this is happening specifically with regard to hypersonic vehicle research, but this is exactly the sort of thing that I am trying to dig up. I have heard similar stories from all sorts of places - including people who would not fit in or could not rise in Yamrika finding a niche job in India to spend a couple of decades doing zilch.


Last edited by shiv on 14 Apr 2015 19:08, edited 1 time in total.

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PostPosted: 14 Apr 2015 19:07 
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Perfect. Now that the true goal is identified fire away.


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PostPosted: 14 Apr 2015 19:20 
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Evaluation of Kerosene Fuelled Scramjet Combustor using a Combination of Cooled and Uncooled Struts

Quote:
CONCLUSIONS

The static test of the kerosene fuelled scramjet combustor has been carried out for the supersonic combustion test duration of 20 s by creating low back pressure at the exit of the scramjet combustor using ejector system. In this test, cooled strut configuration for the Stage-II and heat sink design for the Stage-I and Stage-III struts have been used. They are made of Nimonic C-263 alloy. Test was carried out at a global fuel equivalence ratio of 1.0.

The performance of the kerosene feed system along with the fuel injection struts is found to have met the desired requirement based on the performance parameters viz., Strut injection pressures and mass flow rate of kerosene. These parameters are found to be steady with respect to time for the entire test duration.

Ignition and stable combustion of kerosene fuel with vitiated air have been achieved at a combustor entry Mach number of 2.0 for 20 seconds test duration.

During the supersonic combustion of kerosene fuel with vitiated air, the maximum rise in non-dimensional wall static pressure and non-dimensional gas temperature measured near the inner wall of bottom wall are obtained to be 0.24 and 6.85 respectively.

Adverse pressure gradient has been overcome by employing ejector system and its effect is seen between 27.3 s and 39.1 s during the supersonic combustion. Due to the ejector action the non-dimensional wall static pressure at the exit of combustor has dropped from 0.12 to 0.064. Low back pressure created by the ejector system has aided in generating full supersonic flow in the entire length of the scramjet combustor.

It is concluded from the results of the scramjet combustor test carried out for 22.5 s (i.e., 20 s supersonic combustion (reacting flow) + 2.5 s vitiated air flow (non-reacting flow)) using kerosene fuel that the fuel injection struts have withstood the severe flow field conditions during the test. This is corroborated from the steady fuel injection pressures of the struts and from the mass flow rate of kerosene injected into the combustor. The combustor performance in terms of the thrust is found to be meeting the mission requirement. Hence, the cooled strut configuration used for the Stage-II and heat sink configuration for the other two stages with Nimonic C-263 alloy as material of construction would suffice the 20 s hypersonic flight mission requirement.


I remember there being another paper about the scramjet combustor struts containing experimental results and pics of struts post 20s burn but can't locate that now. The strut pic in this paper is in way way better condition than the one's in the paper I am unable to locate. I will say that we have come a long way w.r.t. scramjet combustion.


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PostPosted: 14 Apr 2015 21:57 
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TSJones wrote:
But we will grunt it out eventually, stubbornly spending gazillions and making lots of mistakes. It's what we specialize in. ...
Sorry to bother you.


We also specialize in cutting food stamp weekly allowance per person from $29 to $20.01 while going on nonsensical ego trips - building a manned rocket that goes nowhere.

Me too sorry to bother you.


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PostPosted: 14 Apr 2015 23:58 
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Since I have worked on Hypersonic vehicle Physics in past (not HSTDV but the one which ISRO is developing), I think I have some idea of the stuff. I would consider myself lucky if I could see practical hypersonic plane flying before I die (missiles with scramjet technology might come a little sooner than that). And I do have at least 40-50 yrs of life left still (hopefully :mrgreen: ). And I am quite hopeful that India will be among the creators of the first hypersonic plane, whenever it happens.



The point is not that this is a technically demanding field. It is more that DRDO has set numerous flight announcements-it used to be four years in the future, more recently there was supposed to be a flight package for March 2015.

Of course there is nothing.

Now if an engineering team cannot determine in January, as announced, that they do not have a flyable prototype for March, well that is simply a lie. It is not even incompetent-one can't possibly be that derelict.


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PostPosted: 15 Apr 2015 00:19 
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Sorry to be harsh/truthful.


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PostPosted: 15 Apr 2015 01:21 
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Aah galloping milestones.


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PostPosted: 15 Apr 2015 01:37 
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1. Funding was oozing out of every orifice for any research oriented institution starting about 15 years ago in India. So much that folks didnt know what to do with the money.
2. The ARRA (I aint expanding it for ya) was a similar gross waste, and on a smaller scale, things like NRI (imagine your own expansion) have spent billions putting pools in peoples backyards on this side of the pond.

Research is a magnet for fraud. 99% of honest experimental effort is doomed at the start. Combine the two and you quickly see why the smart brains of eyeeyetees and emeyetees want to only do theoretical/simulashun work. Getting your hands dirty is a very dirty business.

If you work on a khadi gramodyog scale, you will end up in this situation. The only solution to actually accomplishing a half-assed solution on time is to fund r&d at multiple independent and competing institutions on an industrial scale.

You can have greed (and a working prototype on time), or job security and exclusive mining rights to an entire field of science but not both.


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