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NAMICA

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This is the no 2 article in the three part series by Dr Anantha Krishnan M of Tarmak 007 .

He sheds light on the developmental challenges , the various technologies developed and what changes were incorporated in the cruise and launch vehicle after the first test.

View attachment 67228

https://www.onmanorama.com/news/nat...hypersonic.amp.html?__twitter_impression=true

Some points to note.

1. The scientists associated with this project carried out extensive tests on the thermo structural dynamics of both the cruise and launch vehicles , static and dynamic tests of the upper panel separation mechanism, payload ejection for the better part a decade.

The flight envelope of the Agni 1 booster used for this test is distinctly different than when it is used as a ballistic missile. I reckon it has more to do with extended horizontal flight for a good period of time through the dense parts of the atmosphere which imposes additional thermal loads on the booster.

2. Extensive resonance testing were carried out for the cruise and launch vehicle combination to identify and validate the vehicle dynamics
Excessive Vibration levels can make or break a mission by imposing additional aerodynamic loads and stresses on the vehicles. Remember The Martian .

3. The people want the cruise vehicle aka HSTDV to cruise for a distance of 2000 kms. That's the intended target for range. To be covered in 16 minutes . This will be awesome if it can be achieved. I will even be happy for 1500-1600 km range .

4. The actual hardware realisation phase began in 2016 .

5. Extensive thermo aerodynamics studies were carried out on cruise vehicle flow path, intake design, single expansion ramp nozzle, engine flow path, combustors ,etc.

6. After the first test, the scientists and engineers changed a portion of airframe section based on its previous dynamic behaviour. They modified the ejection mechanism and panel seperation scheme too . The first test proved valuable insight on where and how to improve further . The changes were then proved through resonance testing of the integrated vehicles.

7. Thermal barrier coatings have been developed exclusively for use on HSTDV. Besides materials and alloys were properly chosen to cope with the enormous thermal tests and still maintain its structural integrity .

Establishing cost effective production processes with a high QA/QC standard for these various alloys and ceramics will be the next big challenge.

Materials is one side of the coin. The other side is manufacturing them in bulk in a cheap manner buy while maintaining the correct quality and dimensional accuracies. This part is even harder than most of us think.

View attachment 67229
Hypersonic missile is already under development it means HSTDV will be our powered glide vehicle.
 

mist_consecutive

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It's only meant for ship submarine launched variant is under development.
Oh, is it? This article from Jan says it is also for Kilo-class submarines

It will be carried by Kolkata class, Rajput class and Delhi class destroyers. It will also be fitted on to Kamorta class corvettes and Talwar class frigates. Indian Navy's biggest fleet of Sindhughosh Class submarines will also carry Varunastra. The fleet currently has 9 operating vessels.

Didn't knew Varunastra is operational with Navy since Jan btw :)
 

Killbot

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That is excellent news then :clap2: It means we won't have to beg Finmeccanica who were blacklisted for corruption for black shark torpedoes.

And our long-toothless Kalvari's & Shisumar will get lethal attack weapons :)
Varunastra is a ship launched torpedo. Can you put the same one on a sub?
 

mist_consecutive

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Varunastra is a ship launched torpedo. Can you put the same one on a sub?
I am not aware, what I can see is, the diameter of the torpedo & submarine torpedo tube are same.
What differs is the launch mechanism, and theoretically ship-launch torpedoes have to face a larger amount of stress while being launched (they are literally dropped from fast moving ship into water from height).

Any naval expert who can explain difference in ship-launch & submarine launch torpedos ?
 

Gautam Sarkar

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Any naval expert who can explain difference in ship-launch & submarine launch torpedos ?
I am no expert but allow me. Torpedo launch from subs have 2 common modes : Push-out & swim-out.

In Push-out mode the torpedo is pushed out using gas pressure and in swim-out mode the torpedo tube is flooded & then the torpedo swims out of the tube using it own power. Both modes have their own advantages & dis-advantages.

These is a sub version of the Varunastra under development named "Takshak".
 

mist_consecutive

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I am no expert but allow me. Torpedo launch from subs have 2 common modes : Push-out & swim-out.

In Push-out mode the torpedo is pushed out using gas pressure and in swim-out mode the torpedo tube is flooded & then the torpedo swims out of the tube using it own power. Both modes have their own advantages & dis-advantages.

These is a sub version of the Varunastra under development named "Takshak".
But why ship-launched Varunastra cannot be launched from Submarine?

Push-out mode using high-pressure water - same thing (but much safer) as using compressed air / explosive to push out torpedo from ship's launch tubes.

Swim-out mode - Even safer, as torpedo just moves on its own propulsion.
 

Gautam Sarkar

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But why ship-launched Varunastra cannot be launched from Submarine?
The ship launch of torpedoes require the torpedo to withstand a violent crash on to water. Then the torpedo swims out. To withstand that the torpedo's front end has to be reinforced which will add weight. Then you have to balance the weight to ensure the torpedo doesn't go nose down when in water.

No such problems exists for sub launched torpedoes. A ship launch Varunastra can be used form a sub in theory. But it will be inefficient. Space & weight is a premium on subs. Don't carry more than needed.

The sub version is likely going to be faster & longer ranged. It will have a 300KW battery instead of Varunastra's 250KW. It will have better RLGs too. The battery is a weight worth carrying & it is placed at the mid section so minimum problems with balancing.
 

Arihant Roy

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I am unable to fully comprehend some parts of the part three of the series by Tarmak . Although as usual its a great piece and emphasises on the right areas.

https://www.onmanorama.com/news/nat...fly-part-3.amp.html?__twitter_impression=true

The engineers are working on a new booster motor which will reduce aerodynamic forces and stresses induced on the HSTDV vehicle. This will allow the vehicle to be launched without any fairings. And the scientists are hoping to test this out in the very next launch.

As far I know, the stresses induced and aerodynamic forces are proportional to the booster speeds and the AoA of the cruise vehicle. Lower speeds means lower dynamic stresses and also lower skin drag . Lower kinetic heating .

So are you we to assume that the current booster takes hSTDV to a much higher Mach no during the later stages of flight regime. More than M6.5 . Which necessitates the use of the fairings . With a newer booster the peak velocity would be within the speed limits of the HSTDV. So a launch without any fairings can be attempted .


PS- This means our oballisticmissile tech from the late 90s and early 2000s and solid propellants science of that era is almost at par with other countries . We are so sophisticated that we need a new booster to be able to launch HSTDV without fairings . This is just awesome.


APJ KALAM is a legend of a legend. An ultra legend. If I bring a Dragon ball analogy here , HE is super saiyan four level.

He dreamt big on Hypersonics . He got his inspiration from Lord Krishna's lord 🙏 sudarshan chakra. He envisaged a hypersonic mother missile/drone which would carry smaller guided missiles warheads , take them to the general area, launch them and return back to base. Reusable .He was ahead of his time by 20-30 years . Even Uncle Sam with a defense budget that is almost two times of India's total budget doesn't have such a niche capability .
 

NAMICA

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I am unable to fully comprehend some parts of the part three of the series by Tarmak . Although as usual its a great piece and emphasises on the right areas.

https://www.onmanorama.com/news/nat...fly-part-3.amp.html?__twitter_impression=true

The engineers are working on a new booster motor which will reduce aerodynamic forces and stresses induced on the HSTDV vehicle. This will allow the vehicle to be launched without any fairings. And the scientists are hoping to test this out in the very next launch.

As far I know, the stresses induced and aerodynamic forces are proportional to the booster speeds and the AoA of the cruise vehicle. Lower speeds means lower dynamic stresses and also lower skin drag . Lower kinetic heating .

So are you we to assume that the current booster takes hSTDV to a much higher Mach no during the later stages of flight regime. More than M6.5 . Which necessitates the use of the fairings . With a newer booster the peak velocity would be within the speed limits of the HSTDV. So a launch without any fairings can be attempted .


PS- This means our oballisticmissile tech from the late 90s and early 2000s and solid propellants science of that era is almost at par with other countries . We are so sophisticated that we need a new booster to be able to launch HSTDV without fairings . This is just awesome.


APJ KALAM is a legend of a legend. An ultra legend. If I bring a Dragon ball analogy here , HE is super saiyan four level.

He dreamt big on Hypersonics . He got his inspiration from Lord Krishna's lord 🙏 sudarshan chakra. He envisaged a hypersonic mother missile/drone which would carry smaller guided missiles warheads , take them to the general area, launch them and return back to base. Reusable .He was ahead of his time by 20-30 years . Even Uncle Sam with a defense budget that is almost two times of India's total budget doesn't have such a niche capability .
Then HSTDV would require canister for storage if I am not wrong similar technology will be used in our hypersonic missile too as it will be also launched without fairings.

Regarding abdul kalam dream I think he was talking about avatar.
 

SavageKing456

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Then HSTDV would require canister for storage if I am not wrong similar technology will be used in our hypersonic missile too as it will be also launched without fairings.

Regarding abdul kalam dream I think he was talking about avatar.
What exactly is avatar?
Is it one of our reusable shuttle type vehicle?
 

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