Indian Hypersonic Propulsion Developments

It seems, similar-sized TEL (12 wheels) appears to be carrying both BrahMos and LR-ASHM.

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Correct, the difference is that Pralay is a heavier missile, thus only two per TEL. Brahmos is 3 ton while Pralay is 5 ton.
 
^^
That project (or sub-project if you like) is part of P-191 A5 mkII and was directly under the A5 project director who is now promoted as the overall Agni 5 Program Director. There are various posts like Technology Director, Project director etc so this is likely a TD , gateway to the bigger thing.
 
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One old technical committee report of the scramjet rig work that I saved at the time and forgot.
besides, if we follow the fuel development curve, we would also get into the recipient internal fuel tank part and thereby further across the integration into the CV itself. So the vjravega fuel JP7 shelf life determination work started last year and as the MRSAM propellant ageing test show, takes probably a year or more, maybe differs from solid prop to liquid hydrocarbon obviously, and esp this is endothermic fuel that also act as the coolant ? so they also have to do tests on carbon soot forming etc /
Then we got the 2 types of non axi symmetric fuel tank being made by DRDL for this purpose, those are to be the airframe section itself. This makes it very complex.
Interestingly found other Boron infused solid propellant work that is also for solid ramjet, as well as work on Boron based Gel fuel. But those are for solid ramjet, not liquid scramjet. Though it is possible theoretically to use AL infused fuel rich propellant for mach 6 flight at 25km altitude. The Boron infused solid propellant has shown Isp greater than traditional HTPB AP mix propellant in the range of almost 252 s .

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No , the slide pic. Either here or in the other munition missiles thread, over 2 years ago. The shell one is the reentry vehicle shell structure of Agni 5 class rv.
 

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Thermo structural qualification of HSTDV control surface , believe this was posted before somewhere


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The control surface structure above, is probably similar to how the other RV glider body fins are manufactured to make the leading edges withstand the heat generated during flight. The HGV-KV of LRAShM and the BM-04 RV both are to withstand the aerodynamic heating load for a much longer duration, hence maybe ablation resistant coating is applied on the leading edge part.

LRAShM got less blunt/sharp nose point with heat shield , and the general trajectory showed just about reentry condition at 80-90km altitude in poster (likely representative). So back in 2015-2019 period when DRDL scientists were publishing many hypersonic boost-glide trajectory optimisation related papers, it was conceptualised for optimised trajectory control algorithm based on specific constraints like L/D ratio as control parameter.

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maybe this is why its a hybrid HGV & KV like it was mentioned in the wind tunnel testing tender doc, it will use glide role for midcourse and use the sustainer motor for endgame. Like it is in the papers, the glide flight will happen at altitude of 30-50km region , then for the endgame when seeker is activated it will have juice for final maneuver and impact. Mission wise endgame will be chosen with specific angle of attack aka terminal impact speed will vary like in the graph inside. Enemy radar horizon and FCR will only get glimpse at the last few seconds.
 
Papers of the above post are attached here.

Another interesting part is the booster stage, as per info-graphic and estimates the 1.3meter dia booster is about 3.25meter long. That is a bit less than K4 booster 1.4m dia 5.5m long , but more than A1P P1 motor 1.2m dia 4.5 meter length. So taking K4 mission cue,

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this booster can obviously propel the HGV-KV to desired altitude while keeping the kinematic needed for the HGV to operate as wanted. 4km/s is almost mach 12 at 90km altitude in space , so LRAShM can attain max 3.3km/s speed (mentioned at Vigyan event) at altitude well below 90km before reentry conditions. Hence with optimised trajectory , to satisfy mission specific conditions it can give a range far exceeding the touted 1500km easily without even leaving the atmosphere.
But because it is antiship, it makes no sense to go further hence hybrid HGV-KV design, rather accuracy is the first priority over range due to seeker op. Seeker will be active in the last 30-50km possibly a bit more, do not know. it also depend on the thermal battery. So it is not a powered hypersonic cruise missile but it flies like a cruise missile.

In land attack mode this pure HGV will be able to strike well over 2000-2200 km. Whether they use the same BM-04 RV is to be seen but like the Uttam radar, a base technology is established and flight test proven. Now scale up and down as per platform based product.
 

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Papers of the above post are attached here.

Another interesting part is the booster stage, as per info-graphic and estimates the 1.3meter dia booster is about 3.25meter long. That is a bit less than K4 booster 1.4m dia 5.5m long , but more than A1P P1 motor 1.2m dia 4.5 meter length. So taking K4 mission cue,

View attachment 42584

this booster can obviously propel the HGV-KV to desired altitude while keeping the kinematic needed for the HGV to operate as wanted. 4km/s is almost mach 12 at 90km altitude in space , so LRAShM can attain max 3.3km/s speed (mentioned at Vigyan event) at altitude well below 90km before reentry conditions. Hence with optimised trajectory , to satisfy mission specific conditions it can give a range far exceeding the touted 1500km easily without even leaving the atmosphere.
But because it is antiship, it makes no sense to go further hence hybrid HGV-KV design, rather accuracy is the first priority over range due to seeker op. Seeker will be active in the last 30-50km possibly a bit more, do not know. it also depend on the thermal battery. So it is not a powered hypersonic cruise missile but it flies like a cruise missile.

In land attack mode this pure HGV will be able to strike well over 2000-2200 km. Whether they use the same BM-04 RV is to be seen but like the Uttam radar, a base technology is established and flight test proven. Now scale up and down as per platform based product.
In Hypersonic cruise missiles.
The cruise phase is a flight profile/characteristic.
While it has become common to associate it with scramjet, but ultimately scramjet itself is just a propulsion method to push the missile forward and attain sustained Hypersonic speed at sustained altitude
The rocket in LR-ASHM does the same thing, propelling it forward and attain sustained Hypersonic speed at sustained altitude.
Scramjet uses air as an oxidizer while rocket motor has entire fuel inside the missile.
So scramjets are lot more efficient than rocket engine.
Scramjet right now is the most efficient method of propulsion for a HCM but its not the only method of propulsion to attain sustained Hypersonic speed while cruising at sustained altitude.
Papers of the above post are attached here.

Another interesting part is the booster stage, as per info-graphic and estimates the 1.3meter dia booster is about 3.25meter long. That is a bit less than K4 booster 1.4m dia 5.5m long , but more than A1P P1 motor 1.2m dia 4.5 meter length. So taking K4 mission cue,

View attachment 42584

this booster can obviously propel the HGV-KV to desired altitude while keeping the kinematic needed for the HGV to operate as wanted. 4km/s is almost mach 12 at 90km altitude in space , so LRAShM can attain max 3.3km/s speed (mentioned at Vigyan event) at altitude well below 90km before reentry conditions. Hence with optimised trajectory , to satisfy mission specific conditions it can give a range far exceeding the touted 1500km easily without even leaving the atmosphere.
But because it is antiship, it makes no sense to go further hence hybrid HGV-KV design, rather accuracy is the first priority over range due to seeker op. Seeker will be active in the last 30-50km possibly a bit more, do not know. it also depend on the thermal battery. So it is not a powered hypersonic cruise missile but it flies like a cruise missile.

In land attack mode this pure HGV will be able to strike well over 2000-2200 km. Whether they use the same BM-04 RV is to be seen but like the Uttam radar, a base technology is established and flight test proven. Now scale up and down as per platform based product.
In Hypersonic cruise missiles.
The cruise phase is a flight profile/characteristic.
While it has become common to associate it with scramjet, but ultimately scramjet itself is just a propulsion method to push the missile forward and attain sustained Hypersonic speed at sustained altitude
The rocket in LR-ASHM does the same thing, propelling it forward and attain sustained Hypersonic speed at sustained altitude.
Scramjet uses air as an oxidizer while rocket motor has entire fuel inside the missile.
So scramjets are lot more efficient than rocket engine.
Scramjet right now is the most efficient method of propulsion for a HCM but its not the only method of propulsion to attain sustained Hypersonic speed while cruising at sustained altitude.
 
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In Hypersonic cruise missiles.
The cruise phase is a flight profile/characteristic.
While it has become common to associate it with scramjet, but ultimately scramjet itself is just a propulsion method to push the missile forward and attain sustained Hypersonic speed at sustained altitude
Yes, the key aspect here is the ramjet, scramjet, dual mode ramjet/scramjet etc are varied form of air breathing propulsion. This is where the relation with respect to altitude is easier to understand. The further we go up the atmosphere air density lessen, oxygen is less in air. So a propulsion technique that relies on the airflow turned supersonic inside the combustion chamber need sufficient amount of the oxidizer to keep the combustion running. That is possible in the dense lower altitude region of 20-35km.
Now due to relative dense atmosphere, the aerodynamic drag and subsequent aerodynamic heating is also higher across the leading edges of the aerial vehicle/cruise vehicle due to its speed. So its a design choice to choose at which altitude it can give optimum performance. The HCM will be able to cruise at 25-30km altitude for long duration of its flight.

The rocket in LR-ASHM does the same thing, propelling it forward and attain sustained Hypersonic speed at sustained altitude.
Scramjet uses air as an oxidizer while rocket motor has entire fuel inside the missile.
So scramjets are lot more efficient than rocket engine.
Scramjet right now is the most efficient method of propulsion for a HCM but its not the only method of propulsion to attain sustained Hypersonic speed while cruising at sustained altitude.
Yes, here the difference is very high initial kinematic thrust provided by a solid rocket motor for LRAShM / HGV case vs a throughout powered flight for scramjet powered HCM.
The rocket motor booster give high thrust initially but can only burn for a limited time, even if we consider max burn time of say 60-80 second which would be a very long burn in case of rocket motors. This is possibly satisfactory for an HGV operating over a 1500km range at a 30-45km altitude region.
In comparison the scramjet will be able to burn for a sustained period of 120-200 seconds duration. This operational period is after the scramjet ignition once the initial booster propels the cruise vehicle to desired altitude and satisfies the required initial thrust condition so the scramjet can ignite which is ~ mach 2 airflow for ignition. This is why it is called Long Duration HCM where we need suitable material that can withstand internal combustion chamber pressure and heating for long duration > 100 sec.
Yes other than scramjet, a rotating detonation wave engine can also propel to hypersonic speed.
 
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Yes, the key aspect here is the ramjet, scramjet, dual mode ramjet/scramjet etc are varied form of air breathing propulsion. This is where the relation with respect to altitude is easier to understand. The further we go up the atmosphere air density lessen, oxygen is less in air. So a propulsion technique that relies on the airflow turned supersonic inside the combustion chamber need sufficient amount of the oxidizer to keep the combustion running. That is possible in the dense lower altitude region of 20-35km.
Now due to relative dense atmosphere, the aerodynamic drag and subsequent aerodynamic heating is also higher across the leading edges of the aerial vehicle/cruise vehicle due to its speed. So its a design choice to choose at which altitude it can give optimum performance. The HCM will be able to cruise at 25-30km altitude for long duration of its flight.


Yes, here the difference is very high initial kinematic thrust provided by a solid rocket motor for LRAShM / HGV case vs a throughout powered flight for scramjet powered HCM.
The rocket motor booster give high thrust initially but can only burn for a limited time, even if we consider max burn time of say 60-80 second which would be a very long burn in case of rocket motors. This is possibly satisfactory for an HGV operating over a 1500km range at a 30-45km altitude region.
In comparison the scramjet will be able to burn for a sustained period of 120-200 seconds duration. This operational period is after the scramjet ignition once the initial booster propels the cruise vehicle to desired altitude and satisfies the required initial thrust condition so the scramjet can ignite which is ~ mach 2 airflow for ignition. This is why it is called Long Duration HCM where we need suitable material that can withstand internal combustion chamber pressure and heating for long duration > 100 sec.
Yes other than scramjet, a rotating detonation wave engine can also propel to hypersonic speed.
One doubt- What about Zircon? Is it fake- what my hunch is that Russians are fooling us all these times that it is not some Hypersonic Scramjet but your regular Rocket Powered Hypersonic Cruise just like our Shaurya Missile or am i wrong?
 
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One doubt- What about Zircon? Is it fake- what my hunch is that Russians are fooling us all these times that it is not some Hypersonic Scramjet but your regular Rocket Powered Hypersonic Cruise just like our Shaurya Missile or am i wrong?
Zircon is their system. if it happens ie Brahmos 2 it may happen through the jv route but unlikely at present. So far all Brahmos related work has been happening locally for a few years now.
 

This technology will serve as a foundation for the upcoming Indian missiles. The development of anti-aircraft (bomber), hypersonic missile defense with remarkable speed, accuracy, and range. For increased range, it should have a computerized throttleable (stop/start) capability. Let ISRO know about this... they might use this technology. Bravo for this accomplishment, DRDO scientists 💐 (y)
 
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