Impact of dual impulse , Air breathing and scram-jet technology on Indian missile program.

HariPrasad-1

Senior Member
Joined
Jan 7, 2016
Messages
9,573
Likes
21,017
Country flag
Hi guys,

ISRO is all set to test a loads of new technologies improve the performance of its launch vehicles which includes and low weight parts, Air breathing technology, scram jet etc.

I am starting this new thread to discuss the implications of these technologies on India's missile program. Once we start using All composite missile with high efficiency NEPE like fuel with low weight components and motors with Air breathing and scram jet technology than we may bring manifold efficiency in our missile technology. Can we use that duel pulse technology in our big motors? Once we incorporate all these new technology than what is the degree of efficiency can we achieve in our missiles?

Let us discuss.
 

HariPrasad-1

Senior Member
Joined
Jan 7, 2016
Messages
9,573
Likes
21,017
Country flag
http://www.defencenow.com/news/820/...ding-to-execute-crucial-defence-projects.html

Here is a thread where you will find a mention of NANO missiles.

http://timesofindia.indiatimes.com/...rease-missiles-range/articleshow/15286191.cms

Here the plan to increase the range of missile is discussed. We know that the new AAD with composite structure is tested with longer range and higher speed. Composite motor can play a very vital role in enshrining the the range and boosting of speed. composite structure played a very important role in boosting the range of Agni series in A III onward missiles.
 

HariPrasad-1

Senior Member
Joined
Jan 7, 2016
Messages
9,573
Likes
21,017
Country flag
The weight of hardware is almost 10 to 13% of the weight of missile. Rest 85% is fuel. Out of that 60% shall be oxidizer. This means that almost half of the weight of missile shall be oxidizer. if we can make first stage of missile (Which shall have about 60% of the weight of the missile) air breathing than we can save 30% of the weight of the total missile. (50% of 60% which is 30%). That will give us a 42% higher T/W ratio. This should make our missile much faster and much longer ranged. We can have an A5 like missile of say 10000 to 12000 KM range minimum.If we incorporate Composite motor and dual impulse motor into this stage than our missile can really be very compact, very fast and very cost effective.
 

Screambowl

Ghanta Senior Member?
Senior Member
Joined
Jan 1, 2015
Messages
7,950
Likes
7,908
Country flag
Like Russian Bulava , a qasi BM, India has already shown it's talent in building a qasi BM like shaurya.

I am not very sure about whether dual pulse motor can be used on big rockets. But yes in SAM , AAM or tactical rockets it can be used. But then these are solid fuel motors not scramjet.

The tests are still going on in few countries with dual pulse motor. (Not scramjet)
 

HariPrasad-1

Senior Member
Joined
Jan 7, 2016
Messages
9,573
Likes
21,017
Country flag
Like Russian Bulava , a qasi BM, India has already shown it's talent in building a qasi BM like shaurya.

I am not very sure about whether dual pulse motor can be used on big rockets. But yes in SAM , AAM or tactical rockets it can be used. But then these are solid fuel motors not scramjet.

The tests are still going on in few countries with dual pulse motor. (Not scramjet)
Yes and you forget to mention K4. These missiles never leaves atmosphere and travels at hypersonic speed. Here the secrete of speed lies in its fuel which is once again classified. The benefit of hyper sonic speed with scramjet is that it uses atmosphere air and hence very low weight that once again increases the speed. You can build the missile like shaurya or K series without scramjet but it will have a weight penalty and they will be costly as well. With scram jet, we can do that very cost effectively.

We can use scram jet as well but that would require more than mac 2 speed to start scram jet engine which is a negative point. That will add one more stage into rocket.

Composite motor with dual impulse with air breathing can do wonders if it is incorporated into our missiles.
 

HariPrasad-1

Senior Member
Joined
Jan 7, 2016
Messages
9,573
Likes
21,017
Country flag
Like Russian Bulava , a qasi BM, India has already shown it's talent in building a qasi BM like shaurya.

I am not very sure about whether dual pulse motor can be used on big rockets. But yes in SAM , AAM or tactical rockets it can be used. But then these are solid fuel motors not scramjet.

The tests are still going on in few countries with dual pulse motor. (Not scramjet)
Quasi ballistic is a trajectory which will enhance the missile range compared to lofted trajectory. However accuracy will go down. Our scientist have managed and excellent fusion of quasi ballistic trajectory with very low error in K series. However quasi ballistic is not the trajectory where missile will travel furthermost. It will be minimum energy trajectory where the missile can travel further most.
 

Chinmoy

Senior Member
Joined
Aug 12, 2015
Messages
8,678
Likes
22,541
Country flag
if we can make first stage of missile (Which shall have about 60% of the weight of the missile) air breathing than we can save 30% of the weight of the total missile.
Here you have forgot a very basic thing about propulsion. Air breathing engines like RAMJET or SCRAMJET can't propel a missile or rocket from standstill. So the first stage would have to be a standard rocket engine for standard propulsion.

You could have a RAMJET second stage for cruise or thrust, but IMO it is better to have a pulse jet rocket engine for distance, as RAMJET/ SCRAMJET are simply gas guzzling engines.

My ideal plan for a missile would be to have a small rocket thruster as the first stage to provide the needed thrust to propel the system in air, just like what we have in Brahmos. Then the second stage should have pulse jet engine like BARAK8 for prolonged flight distance with minimum fuel and RAMJET/ SCRAMJET should come in act at the terminal stage to beat up any CIWS.
 

HariPrasad-1

Senior Member
Joined
Jan 7, 2016
Messages
9,573
Likes
21,017
Country flag
Here you have forgot a very basic thing about propulsion. Air breathing engines like RAMJET or SCRAMJET can't propel a missile or rocket from standstill. So the first stage would have to be a standard rocket engine for standard propulsion.

You could have a RAMJET second stage for cruise or thrust, but IMO it is better to have a pulse jet rocket engine for distance, as RAMJET/ SCRAMJET are simply gas guzzling engines.

My ideal plan for a missile would be to have a small rocket thruster as the first stage to provide the needed thrust to propel the system in air, just like what we have in Brahmos. Then the second stage should have pulse jet engine like BARAK8 for prolonged flight distance with minimum fuel and RAMJET/ SCRAMJET should come in act at the terminal stage to beat up any CIWS.
Ramjet and scramjet need air (Oxygen) and hence can not operate outside atmosphere.
 

Chinmoy

Senior Member
Joined
Aug 12, 2015
Messages
8,678
Likes
22,541
Country flag
Terminal phase shall by and large be gravity and kinetic energy driven flight and will not require air breathing.
Now that is one serious flaw. We are talking about MIRV and MaRV, but not about thrust in reentry.

Now in reentry phase obviously its gravity which does play the vital part, but along with it if you could use maneuverability with added guidance, then you are talking about one heck of an system.

Moreover, I was talking about all sort of missiles including BM, CM, QBM, SAM. Just think about using pulse jet engine in Akash system for mid course propulsion and RAMJET for terminal phase instead of just RAMJET like now.
 

HariPrasad-1

Senior Member
Joined
Jan 7, 2016
Messages
9,573
Likes
21,017
Country flag
Now that is one serious flaw. We are talking about MIRV and MaRV, but not about thrust in reentry.

Now in reentry phase obviously its gravity which does play the vital part, but along with it if you could use maneuverability with added guidance, then you are talking about one heck of an system.

Moreover, I was talking about all sort of missiles including BM, CM, QBM, SAM. Just think about using pulse jet engine in Akash system for mid course propulsion and RAMJET for terminal phase instead of just RAMJET like now.
Its all right if you talk about using them in atmosphere. In reentry vehicle, other small engines are used for course corrections only.
 

HariPrasad-1

Senior Member
Joined
Jan 7, 2016
Messages
9,573
Likes
21,017
Country flag
I would obviously love to use dual impulse motor in SAM like akash. I think tht when Akash was conceived, no advance duel impulse motor technology was available. Now we can switch over to dual impulse motor like LRSAM.
 

Chinmoy

Senior Member
Joined
Aug 12, 2015
Messages
8,678
Likes
22,541
Country flag
Its all right if you talk about using them in atmosphere. In reentry vehicle, other small engines are used for course corrections only.
If you look into the reentry of Prithvi, you could see that it doesn't follow a predetermined path and does do a bit of glide maneuver. Now in this stage, if you could use a RAMJET engine, you could boost its flight path by another 20 to 30 km easily from the intended point of impact if need arise.

But again I think using it in ICBM would be loss of resource. Its suitable for SRBMs and MRBM along with TBM and QBM.
 

HariPrasad-1

Senior Member
Joined
Jan 7, 2016
Messages
9,573
Likes
21,017
Country flag
If you look into the reentry of Prithvi, you could see that it doesn't follow a predetermined path and does do a bit of glide maneuver. Now in this stage, if you could use a RAMJET engine, you could boost its flight path by another 20 to 30 km easily from the intended point of impact if need arise.

But again I think using it in ICBM would be loss of resource. Its suitable for SRBMs and MRBM along with TBM and QBM.
No that glide maneuver is to avoid ABM. How Scramjet can be used in terminal phase? It is a huge stage may be many more time bigger than reentry vehicle itself. How can that be fitted in small reentry vehicle?
 

Chinmoy

Senior Member
Joined
Aug 12, 2015
Messages
8,678
Likes
22,541
Country flag
No that glide maneuver is to avoid ABM. How Scramjet can be used in terminal phase? It is a huge stage may be many more time bigger than reentry vehicle itself. How can that be fitted in small reentry vehicle?
A very good question. I was always wondering that why don't we ask such questions which could tickle your grey matters.

Now lets have a look at Brahmos or Akash, which does use RAMJET propulsion. You could see that the air inlet in brahmos is right there at the war head whereas those in akash are around midway.

Now in principle a RAMJET/ SCRAMJET engine are basically long hollow tube, where pressurized air is flown in and mixed with fuel (lot of it) and then let out. The only difference in these two is the air inlet surface area. Look at the hypersonic version of Brahmos which is in planning stage. The air inlet is located at the bottom of the vehicle. This in turn as turned it into a huge system.

You need a supersonic air flow and a surface to accomodate that flow and pressure. Now you don't need a huge intake system like those we are testing to make a SCRAMJET engine. With conveniently placed multiple inlet on the tip, like those in Brahmos, you could compensate for the size of the system.

But again SCRAMJET is not an ideal system for distance. And as I've already mentioned, using it in reentry vehicle would be loss of resource. It would be ideal for system like SHAURYA or SAMs only.
 

Latest Replies

Global Defence

New threads

Articles

Top