Nirbhay Cruise Missile Development

Chinmoy

New Member
Joined
Aug 12, 2015
Messages
8,930
Likes
23,094
Country flag
Do the math again...........It's 0.8 Mach
647 km = 647000 m
50 mins = 3000 sec

Means on average it traveled about 215 meter per second which when converted to mach comes to 0.62 mach. Now on average keeping higher and lower speed on mind, it traveled anywhere in between 0.6 to 0.7 mach on average. So we could safely say that on average its constant speed is somewhere near 0.65 mach.
 

john70

New Member
Joined
Nov 23, 2011
Messages
708
Likes
1,019
Country flag
Why India used a Turbojet engine in latest Nirbhay Cruise missile trial ?


Turbo jet engine developed by HAL for use on pilotless target aircraft, Lakshya likely used on recent Nirbhay Trial In Recent successful test flight of India’s first indigenously designed and developed ‘NIRBHAY’ Long Range Sub-Sonic Cruise Missile achieved the range of 647 km for a total time duration of 50 minutes which was less than what it had covered in its second flight when it covered over 1050 km for a 1-15 minute duration due to which it was widely speculated that drop in performance was largely due to use of Turbojet engine instead of Turbofan engine for the first time . DRDO has not confirmed nor denied use of Turbojet engine instead of a Turbofan engine nor clarified on exact reasons behind the need to use it, but this has not stopped many Defence Analysts from coming up with their own theory why a Turbojet engine was used instead of Turbofan engine used in all previous trials.



Russian supplied NPO Saturn 36MT turbofan engine :
India’s worst kept secret has been that India has been using Russian supplied NPO Saturn 36MT turbofan engine for all previous tests and best two possible reasons why India decided to use older Turbojet engine could be due

1) India might be out of supplied NPO Saturn 36MT turbofan engines and Russians might have hiked prices of them . another reason could be that due to delays in certification of Indigenous Manik Turbofan engine currently under development by GTRE, India might have decided to instead use older Turbojet engine for time being rather than import fresh batch. GTRE’s Manik Engine going though ground tests

2) Another theory is that recent flight test largely stressed on validation of the in-flight performance of the missile and its onboard systems like navigation system and software that use of older Turbojet engine didn’t matter for recent trial.

3) Another speculation is that Manik Turbofan engine which reportedly has completed all ground-based testing successfully is going through final weight reduction measures and might be closer to production and will be ready for flight trials soon on next Nibhay trials and that recent tests were done using older Turbojet engine to validate other key parameters instead.

Use of a turbofan engine in Subsonic cruise missile is quite common and it has been used in many modern Subsonic cruise missiles like American Tomahawk long-range cruise missile and even on Pakistan developed Babur land attack cruise missiles and is widely used on other subsonic cruise missiles.

A Turbofan engine is efficient at subsonic speeds and produces less noise along with it also has better fuel efficiency. A turbofan engine is actually a further development of Turbojet engine which was developed to improve their performances in subsonic regime. A Turbojet engine is inefficient at low-speed flight and is extremely noisy when used in subsonic regime.

Turbojet engine might not be widely used engines on cruise missiles around the world this days but they are still operational around the world and are still used in many mid-range (<500km) Subsonic cruise missiles like Chinese C-802 Anti-ship Subsonic cruise missiles for example due to low cost of production and high reliability largely to cater to export market .


A Turbofan engine like Manik will always remain a preferred choice of the engine which will part of the Production version of Nirbhay Cruise missile when it enters production. Next series of Nirbhay Cruise missile will actually see the use of Manik Turbofan engine which will be a key milestone on long-delayed Nirbhay Cruise missile program.

idrw.org .Read more at India No 1 Defence News Website http://idrw.org/why-india-used-a-turbojet-engine-in-latest-nirbhay-cruise-missile-trial/#more-153054 .
 

Immanuel

New Member
Joined
May 16, 2011
Messages
3,605
Likes
7,574
Country flag
647 km = 647000 m
50 mins = 3000 sec

Means on average it traveled about 215 meter per second which when converted to mach comes to 0.62 mach. Now on average keeping higher and lower speed on mind, it traveled anywhere in between 0.6 to 0.7 mach on average. So we could safely say that on average its constant speed is somewhere near 0.65 mach.
The missile travelled through several waypoints, I am sure they also trialed 'loiter' mode where the missile's speed is decreased and put into a holding pattern. This could explain why the average speed is rather low.
 

Chinmoy

New Member
Joined
Aug 12, 2015
Messages
8,930
Likes
23,094
Country flag
The missile travelled through several waypoints, I am sure they also trialed 'loiter' mode where the missile's speed is decreased and put into a holding pattern. This could explain why the average speed is rather low.
That's what I am saying. One step closer to low speed loitering, although news is that it is designed to fly at a lower speed then earlier said Mach 0.8. Another thing is that they had done it with TurboJet rather then TurboFan.
 

lcafanboy

New Member
Joined
Mar 24, 2013
Messages
5,875
Likes
37,838
Country flag
Why India used a Turbojet engine in latest Nirbhay Cruise missile trial ?
Published November 8, 2017 | By admin SOURCE: Anand SG / FOR MY TAKE / IDRW.ORG


PTAE-7 Turbo jet engine developed by HAL for use on pilotless target aircraft, Lakshya likely used on recent Nirbhay Trial

In Recent successful test flight of India’s first indigenously designed and developed ‘NIRBHAY’ Long Range Sub-Sonic Cruise Missile achieved the range of 647 km for a total time duration of 50 minutes which was less than what it had covered in its second flight when it covered over 1050 km for a 1-15 minute duration due to which it was widely speculated that drop in performance was largely due to use of Turbojet engine instead of Turbofan engine for the first time . DRDO has not confirmed nor denied use of Turbojet engine instead of a Turbofan engine nor clarified on exact reasons behind the need to use it, but this has not stopped many Defence Analysts from coming up with their own theory why a Turbojet engine was used instead of Turbofan engine used in all previous trials.


Russian supplied NPO Saturn 36MT turbofan engine

India’s worst kept secret has been that India has been using Russian supplied NPO Saturn 36MT turbofan engine for all previous tests and best two possible reasons why India decided to use older Turbojet engine could be due 1) India might be out of supplied NPO Saturn 36MT turbofan engines and Russians might have hiked prices of them . another reason could be that due to delays in certification of Indigenous Manik Turbofan engine currently under development by GTRE, India might have decided to instead use older Turbojet engine for time being rather than import fresh batch.


GTRE’s Manik Engine going though ground tests

2) Another theory is that recent flight test largely stressed on validation of the in-flight performance of the missile and its onboard systems like navigation system and software that use of older Turbojet engine didn’t matter for recent trial. Another speculation is that Manik Turbofan engine which reportedly has completed all ground-based testing successfully is going through final weight reduction measures and might be closer to production and will be ready for flight trials soon on next Nibhay trials and that recent tests were done using older Turbojet engine to validate other key parameters instead.

Use of a turbofan engine in Subsonic cruise missile is quite common and it has been used in many modern Subsonic cruise missiles like American Tomahawk long-range cruise missile and even on Pakistan developed Babur land attack cruise missiles and is widely used on other subsonic cruise missiles. A Turbofan engine is efficient at subsonic speeds and produces less noise along with it also has better fuel efficiency. A turbofan engine is actually a further development of Turbojet engine which was developed to improve their performances in subsonic regime. A Turbojet engine is inefficient at low-speed flight and is extremely noisy when used in subsonic regime. Turbojet engine might not be widely used engines on cruise missiles around the world this days but they are still operational around the world and are still used in many mid-range (<500km) Subsonic cruise missiles like Chinese C-802 Anti-ship Subsonic cruise missiles for example due to low cost of production and high reliability largely to cater to export market . A Turbofan engine like Manik will always remain a preferred choice of the engine which will part of the Production version of Nirbhay Cruise missile when it enters production. Next series of Nirbhay Cruise missile will actually see the use of Manik Turbofan engine which will be a key milestone on long-delayed Nirbhay Cruise missile program.

http://idrw.org/why-india-used-a-turbojet-engine-in-latest-nirbhay-cruise-missile-trial/#more-153054 .
 

lcafanboy

New Member
Joined
Mar 24, 2013
Messages
5,875
Likes
37,838
Country flag
Cross post from IDF PARIKRAMA

Some small snippets

Nirbhay Missile
  1. I had written here about the new guidance system work by Israel given to India with full TOT.
  2. The first trial of that was done in a limited test of Nirbhay Missile at 0.6M (much lower than 0.8-0.85M ) for a ~650km
  3. Israel worked on nirbhay in secret, guidance operations and targeting sensors were changed among other things.
  4. This was a sample work for them the work was done along with Indian scientists.
  5. In total the work to be done over multiple tests will catapult Nirbhay to a flight time of approx 90 Minutes and sustained speed of 0.8M over 80% of the flight.
  6. The targeted range is approx 1500km to be tested step by step.
  7. Proposed Cruising mode over 70 Minutes is targeted to cover approx 1150+ km other than boost and final engagement phase covering other 20 minutes.
  8. Warhead design is further minutarised for more mission specific needs.
  9. There are small changes in the body of the missile as well with trimming of wingspan marginally and optimising certain other aspects.
  10. Now the whole missile and canister together is just under 1500 kg.

Rafale
  • MOD had suggested a CBU completely Built Unit procurement for Rafale M owing to time needed to operationalize the DRAL facility.
  • IN is insisting on MII proposition for additional benefit for MIC.
  • IN has also written that beyond MRCBF it's looking at additional Rafale Procurement as well.
  • In the discussion, IN clearly said it has the capacity and need of Rafale numbers which can standalone warrant a MII line for itself.
  • MOD will internally discuss and call IAF and IN for joint discussion on the same.

Safranised Kaveri
  • The present Safran core installed had given Safranised Kaveri an unstable thrust of 6x/9x.
  • The step 1 is stable 65/98 and step 2 which is to be officially targeted to be deployed is 72/110.
  • A further discussion with Saab on fitting this engine on Gripen E had resulted in a mixed response.
  • Safranised Kaveri is much too large for unmodified Gripen so major modification is needed.
  • When asked for the same , saab said it will take time.
  • It has requested India to first finalize the design and operationalize the engine and then give us 5years to modify the bay and equalize the weight, etc etc to start certification process for the Safranised Kaveri Gripen E
  • OTOH F16 is indeed a better host for that engine since the engine willcome with stealth features"Lower IR read" among other features.
  • The F16 has enough space to play around and let that engine breath properly, the air intakes are big enough for uprated Safranised Kaveri engine also.
  • F16 design is said to be an easier integrator for the engine where as the Gripen would need years and years of testing and redesign.
  • The target rate for the engine is 110 with Afterburner but it has not yet reached that.
  • Its high altitude testing will be done in France but stall test here in India.
  • The engine is expected to have similar life values as Russia engines in 72/110Kn format and 65/98 is targeted to be at par with ECO pack like features.
  • It's said that both these engines are targeted to be like M88-4 and M88-3 like needs, life and serviceability.
  • A separate ECO pack for each is planned to enhance its life , serviceability and maintainence perspectives as much as possible.
 

Hari Sud

New Member
Joined
Mar 31, 2012
Messages
3,945
Likes
8,863
Country flag
Need a discussion on shooting down Pakistani Babur cruise missile.

Need an informed opinions only.
 

porky_kicker

New Member
Joined
Apr 8, 2016
Messages
6,030
Likes
44,621
Country flag
guys what if the recent testfire of nirbhay was not with a turbojet engine as being speculated

it could have been a turbofan engine all along

POEIR JETS had a turbofan engine generating 350kgf thrust under manufacturing ,which they tagged under strategic applications.

http://pixr8.com/poeir-jets-indias-first-ever-jet-engine-developed-by-a-private-firm/

this same company had helped develop the Combustion Chamber in about 3-4 months using Metal Additive Manufacturing for HAL 25KN engine, whereas, traditionally, the development of the part would have taken 18-24 months.

just saying everything is possible , since drdo till date has not confirmed the use of turbojet for nirbhay test and also Indian private companies don't exactly tom tom their involvement with strategic projects.

anyways lets keep our options open, since only a fool will trust Indian presstitudes

1.jpg


pic of POEIR JETS SJE-350 turbofan engine
 
Last edited:

Kshithij

DharmaYoddha
New Member
Joined
Jul 25, 2017
Messages
2,242
Likes
1,961
guys what if the recent testfire of nirbhay was not with a turbojet engine as being speculated

it could have been a turbofan engine all along

POEIR JETS had a turbofan engine generating 350kgf thrust under manufacturing ,which they tagged under strategic applications.

http://pixr8.com/poeir-jets-indias-first-ever-jet-engine-developed-by-a-private-firm/

this same company had helped develop the Combustion Chamber in about 3-4 months using Metal Additive Manufacturing for HAL 25KN engine, whereas, traditionally, the development of the part would have taken 18-24 months.

just saying everything is possible , since drdo till date has not confirmed the use of turbojet for nirbhay test and also Indian private companies don't exactly tom tom their involvement with strategic projects.

anyways lets keep our options open, since only a fool will trust Indian presstitudes

View attachment 21498

pic of POEIR JETS SJE-350 turbofan engine

other offerings from POEIR JETS

View attachment 21499
View attachment 21500
Turbojet can't be used on subsonic cruise missile. Turbojet and turbofan are extremely different. Turbojet is you traditional jet motor which uses solid fuel and solely relies on the thrust from the fuel ejection to fly. Due to this, high speed can be achieved by keeping such kind of fuel that is expelled quickly. Ramjet is another form of Turbojet which uses solid fuel but has no solid oxidizer mixed with the fuel. Instead, oxygen is sucked from the air to burn the fuel.

Turbofan is an engine that burns liquid fuel like kerosene, ether etc to rotate the fan and not eject fuel with high momentum. Something like a helicopter fan but smaller. The fan sucks the air and then pushes it back with greater force to propel the vehicle. Here, the fuel is not ejected directly but the fan merely pushes the air back faster - called bypass. The cruise missiles have high bypass while jet engine has low bypass. Cruise missiles are more fuel efficient than jet aircraft. The after burner in jet engine works something like a turbojet by wasting huge fuel

The result of this difference is that turbofan can't fly much faster and is subsonic. Turbojet, however works well when supersonic.

Nirbhay couldn't have been turbojet at all. It is mandatory for it to be a turbofan. Turbofan for cruise missiles have no link with Kaveri engine. Though both are turbofan, Nirbhay uses 4kN thrust while Kaveri is 90kN. The difference in thrust is so huge that Nirbhay turbofan is far easier than Kaveri engine. The problem of single crystal blades, melting points, super alloy etc doesn't arise. 4kN thrust has minimal temperature or pressure, even for the smaller size of Nirbhay and hence easily accomplished.

There should be no doubt that Nirbhay used Turbofan engines
 

Kay

New Member
Joined
Feb 15, 2014
Messages
1,029
Likes
1,354
Country flag
Turbojet can't be used on subsonic cruise missile. Turbojet and turbofan are extremely different. Turbojet is you traditional jet motor which uses solid fuel and solely relies on the thrust from the fuel ejection to fly. Due to this, high speed can be achieved by keeping such kind of fuel that is expelled quickly. Ramjet is another form of Turbojet which uses solid fuel but has no solid oxidizer mixed with the fuel. Instead, oxygen is sucked from the air to burn the fuel.

Turbofan is an engine that burns liquid fuel like kerosene, ether etc to rotate the fan and not eject fuel with high momentum. Something like a helicopter fan but smaller. The fan sucks the air and then pushes it back with greater force to propel the vehicle. Here, the fuel is not ejected directly but the fan merely pushes the air back faster - called bypass. The cruise missiles have high bypass while jet engine has low bypass. Cruise missiles are more fuel efficient than jet aircraft. The after burner in jet engine works something like a turbojet by wasting huge fuel

The result of this difference is that turbofan can't fly much faster and is subsonic. Turbojet, however works well when supersonic.

Nirbhay couldn't have been turbojet at all. It is mandatory for it to be a turbofan. Turbofan for cruise missiles have no link with Kaveri engine. Though both are turbofan, Nirbhay uses 4kN thrust while Kaveri is 90kN. The difference in thrust is so huge that Nirbhay turbofan is far easier than Kaveri engine. The problem of single crystal blades, melting points, super alloy etc doesn't arise. 4kN thrust has minimal temperature or pressure, even for the smaller size of Nirbhay and hence easily accomplished.

There should be no doubt that Nirbhay used Turbofan engines
Western standoff missiles all use turbojet. But turbofans are fuel efficient.
 

Articles

Top