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Another question, how much of a difference does the 2D vector nozzles of the engine can make on the cost of the flying hour compared to flying without using them.

And also, how the 2D vector nozzles of the engine make a difference on the life of the engine. I asked because I used to read that the engine life can go down a lot when using them.

Well MKI uses 3D thrust vectoring. 3D thrust vectoring allow to deflect the thrust in both pitch and yaw whereas 2D uses only two straight vanes above and below the jet exhaust, which will create only pitch movements (no yaw).

Of course 3D TVC helps the jet a lot but if its a stealthy airframe 2D TVC is preferred owing to the fact that when the aircraft starts making Yaw movement too, the probability of detection increases significantly owing to bouncing of waves from all angles.

It is also to be noted 3D TVC is not an absolute requirement .. if we use conventional control systems via on wings and tail, then aerodynamic control surfaces takes space and additional loads are induced on the airframe. Space in wings is already a constraint owing to installation of wing flaps. Tails planes is a factor of drag inducement and cost for maneuverability and stability.

TVC OTOH adds weight, cost and complexity to the aircraft maintenance and operations. The good news is there is no penalty of drag but then its usage is basically proportional to thrust of the engine and desired Maneuverability. But bad news is also there..

Here is a good explanation

Is 3D thrust vectoring, like that found on advanced MiG-29 and Su-27 variants, the threat some say it is when it comes to the within visual range fight?

First, a little thrust vectoring history. The USAF tested a 3D nozzle on the Multi-Axis Thrust Vectored F-16 in the early 1990s. It was found that thrust vectoring was really only useful at speeds below 250 knots (with the F-16; the speed will vary with other jets). Above that speed the jet had enough g available and was maneuverable enough that thrust vectoring didn't add anything. Also, at high speeds, if the nozzles start to swing the jet violently around you're apt to induce unacceptable loads on the airframe.

Thrust vectoring, whether 2D or 3D, is a two-edged sword. If you're going to use it, you'd better kill me now. Ever seen videos of the Super Flanker spinning around like a top and doing back flips at an airshow? First off, the jet is slow – not a place to be in a multi-bogey environment. Second, when thrust is steered off-axis the axial component of thrust is decreased. Axial thrust pushes the jet (and wing) through the air at a speed required to maintain lift. Take away forward thrust, take away speed and lift. Go back to the videos. What's happening? The Flanker is dropping like a rock at slow speed (no lift is being produced by the wing). If the Flanker pilot does not kill me now, the other edge of the sword is about to fall. He's automatically building in vertical turning room for me and it's going to take an unacceptable amount of time for him to get enough smash back to take it away due to his low airspeed. If I'm still alive I'm turning him into a strafe rag.

I flew enough BFM against the Raptor before I retired where the new Raptor pilots were discovering there's a time for thrust vectoring and there's a time to leave that club in the bag.

How To Win In A Dogfight: Stories From A Pilot Who Flew F-16s And MiGs

When we induce additional loads on the airframe and on top the TVC module is an added weight and maintenance issues, we are going to increase time in hanger between sorties for checks and also a cost part in maintenance. Also the schedule Time Between Overhauls TBOs has to be a much narrower window to ascertain the often load induced stress on the air frame and on the TVC part has not resulted into any structural deformity/defect.

If you see IAF MKI engines are rated for 4000h service life and yet the mean time between overhaul is reportedly 1,000 hours with a full-life span ; the titanium nozzle has a mean time between overhaul of 500 hours

According to wiki
In early 2015, Defence Minister Manohar Parrikar stated before Parliament that the Al-31FP had suffered numerous failures, between the end of 2012 and early 2015, a total of 69 Su-30MKI engine-related failures had occurred; commons causes were bearing failures due to metal fatigue and low oil pressure, in response several engine modifications were made to improve lubrication, as well as the use of higher quality oil and adjustments to the fitting of bearings.[51]

The Su-30MKI's Al-31FP powerplant built on the earlier Al-37FU, adding two-plane thrust vectoring nozzles are mounted 32 degrees outward to longitudinal engine axis (i.e. in the horizontal plane) and can be deflected ±15 degrees in one plane. The canting allows the aircraft to produce both roll and yaw by vectoring each engine nozzle differently; this allows the aircraft to create thrust vectoring moments about all three rotational axes, pitch, yaw and roll. Engine thrust is adjusted via a conventional engine throttle lever as opposed to a strain-gauge engine control stick. The aircraft is controlled by a standard control stick. The pilot can activate a switch for performing difficult maneuvers; while this is enabled, the computer automatically determines the deflection angles of the swiveling nozzles and aerodynamic surfaces
Sukhoi Su-30MKI - Wikipedia, the free encyclopedia

Notice the word usage - Metal fatigue
Metal fatigue is the weakening of a material caused by repeatedly applied loads. It is the progressive and localised structural damage that occurs when a material is subjected to cyclic loading. The nominal maximum stress values that cause such damage may be much less than the strength of the material typically quoted as the ultimate tensile stress limit, or the yield stress limit.

Fatigue occurs when a material is subjected to repeated loading and unloading. If the loads are above a certain threshold, microscopic cracks will begin to form at the stress concentrators such as the surface, persistent slip bands (PSBs), and grain interfaces.
Fatigue (material) - Wikipedia, the free encyclopedia

Thus wiki says something which adds to the load induce issues i said above.
 
I would have thought everyone to understand the above post #3346
but it is still a great idea to have it re-stated.

GTG, Tay.
 
I would have thought everyone to understand the above post #3346
but it is still a great idea to have it re-stated.

GTG, Tay.

Well MKI uses 3D thrust vectoring. 3D thrust vectoring allow to deflect the thrust in both pitch and yaw whereas 2D uses only two straight vanes above and below the jet exhaust, which will create only pitch movements (no yaw).

Of course 3D TVC helps the jet a lot but if its a stealthy airframe 2D TVC is preferred owing to the fact that when the aircraft starts making Yaw movement too, the probability of detection increases significantly owing to bouncing of waves from all angles.

It is also to be noted 3D TVC is not an absolute requirement .. if we use conventional control systems via on wings and tail, then aerodynamic control surfaces takes space and additional loads are induced on the airframe. Space in wings is already a constraint owing to installation of wing flaps. Tails planes is a factor of drag inducement and cost for maneuverability and stability.

TVC OTOH adds weight, cost and complexity to the aircraft maintenance and operations. The good news is there is no penalty of drag but then its usage is basically proportional to thrust of the engine and desired Maneuverability. But bad news is also there..

Here is a good explanation

Is 3D thrust vectoring, like that found on advanced MiG-29 and Su-27 variants, the threat some say it is when it comes to the within visual range fight?

First, a little thrust vectoring history. The USAF tested a 3D nozzle on the Multi-Axis Thrust Vectored F-16 in the early 1990s. It was found that thrust vectoring was really only useful at speeds below 250 knots (with the F-16; the speed will vary with other jets). Above that speed the jet had enough g available and was maneuverable enough that thrust vectoring didn't add anything. Also, at high speeds, if the nozzles start to swing the jet violently around you're apt to induce unacceptable loads on the airframe.

Thrust vectoring, whether 2D or 3D, is a two-edged sword. If you're going to use it, you'd better kill me now. Ever seen videos of the Super Flanker spinning around like a top and doing back flips at an airshow? First off, the jet is slow – not a place to be in a multi-bogey environment. Second, when thrust is steered off-axis the axial component of thrust is decreased. Axial thrust pushes the jet (and wing) through the air at a speed required to maintain lift. Take away forward thrust, take away speed and lift. Go back to the videos. What's happening? The Flanker is dropping like a rock at slow speed (no lift is being produced by the wing). If the Flanker pilot does not kill me now, the other edge of the sword is about to fall. He's automatically building in vertical turning room for me and it's going to take an unacceptable amount of time for him to get enough smash back to take it away due to his low airspeed. If I'm still alive I'm turning him into a strafe rag.

I flew enough BFM against the Raptor before I retired where the new Raptor pilots were discovering there's a time for thrust vectoring and there's a time to leave that club in the bag.

How To Win In A Dogfight: Stories From A Pilot Who Flew F-16s And MiGs

When we induce additional loads on the airframe and on top the TVC module is an added weight and maintenance issues, we are going to increase time in hanger between sorties for checks and also a cost part in maintenance. Also the schedule Time Between Overhauls TBOs has to be a much narrower window to ascertain the often load induced stress on the air frame and on the TVC part has not resulted into any structural deformity/defect.

If you see IAF MKI engines are rated for 4000h service life and yet the mean time between overhaul is reportedly 1,000 hours with a full-life span ; the titanium nozzle has a mean time between overhaul of 500 hours

According to wiki
In early 2015, Defence Minister Manohar Parrikar stated before Parliament that the Al-31FP had suffered numerous failures, between the end of 2012 and early 2015, a total of 69 Su-30MKI engine-related failures had occurred; commons causes were bearing failures due to metal fatigue and low oil pressure, in response several engine modifications were made to improve lubrication, as well as the use of higher quality oil and adjustments to the fitting of bearings.[51]

The Su-30MKI's Al-31FP powerplant built on the earlier Al-37FU, adding two-plane thrust vectoring nozzles are mounted 32 degrees outward to longitudinal engine axis (i.e. in the horizontal plane) and can be deflected ±15 degrees in one plane. The canting allows the aircraft to produce both roll and yaw by vectoring each engine nozzle differently; this allows the aircraft to create thrust vectoring moments about all three rotational axes, pitch, yaw and roll. Engine thrust is adjusted via a conventional engine throttle lever as opposed to a strain-gauge engine control stick. The aircraft is controlled by a standard control stick. The pilot can activate a switch for performing difficult maneuvers; while this is enabled, the computer automatically determines the deflection angles of the swiveling nozzles and aerodynamic surfaces
Sukhoi Su-30MKI - Wikipedia, the free encyclopedia

Notice the word usage - Metal fatigue
Metal fatigue is the weakening of a material caused by repeatedly applied loads. It is the progressive and localised structural damage that occurs when a material is subjected to cyclic loading. The nominal maximum stress values that cause such damage may be much less than the strength of the material typically quoted as the ultimate tensile stress limit, or the yield stress limit.

Fatigue occurs when a material is subjected to repeated loading and unloading. If the loads are above a certain threshold, microscopic cracks will begin to form at the stress concentrators such as the surface, persistent slip bands (PSBs), and grain interfaces.
Fatigue (material) - Wikipedia, the free encyclopedia

Thus wiki says something which adds to the load induce issues i said above.
Ok let me rephrase it in simpler terms
  • MKI uses 3D TVC
  • A 3D TVC uses thurst deflection in both Yaw and pitch axis
  • A 2D TVC uses Thrust deflection in Pitch axis
  • When a 3D TVC uses Thrust to deflect in both Yaw and Pitch, radar waves are more easily bounced off from its surface bcz of which its not preferred in stealthier airframes
  • An example is F22 which uses 2D TVC
Now TVC is not an absolute requirement. Modern jets uses conventional control systems via on wings and tail. But these systems takes space and additional loads are induced on the airframe. Space in wings is already a constraint owing to installation of wing flaps. As for the case of Tails planes, it is a factor of drag inducement and cost for maneuverability and stability. Thus a modern jet without TVC has to have a more of tradeoff based solution for factoring in benefits being offerred by a TVC system

But there are negatives to TVC system too. It basically adds weight, cost and complexity to the aircraft maintenance and operations.
Its benefit in combat is best summarised by this explanation

Is 3D thrust vectoring, like that found on advanced MiG-29 and Su-27 variants, the threat some say it is when it comes to the within visual range fight?

First, a little thrust vectoring history. The USAF tested a 3D nozzle on the Multi-Axis Thrust Vectored F-16 in the early 1990s. It was found that thrust vectoring was really only useful at speeds below 250 knots (with the F-16; the speed will vary with other jets). Above that speed the jet had enough g available and was maneuverable enough that thrust vectoring didn't add anything. Also, at high speeds, if the nozzles start to swing the jet violently around you're apt to induce unacceptable loads on the airframe.

Thrust vectoring, whether 2D or 3D, is a two-edged sword. If you're going to use it, you'd better kill me now. Ever seen videos of the Super Flanker spinning around like a top and doing back flips at an airshow? First off, the jet is slow – not a place to be in a multi-bogey environment. Second, when thrust is steered off-axis the axial component of thrust is decreased. Axial thrust pushes the jet (and wing) through the air at a speed required to maintain lift. Take away forward thrust, take away speed and lift. Go back to the videos. What's happening? The Flanker is dropping like a rock at slow speed (no lift is being produced by the wing). If the Flanker pilot does not kill me now, the other edge of the sword is about to fall. He's automatically building in vertical turning room for me and it's going to take an unacceptable amount of time for him to get enough smash back to take it away due to his low airspeed. If I'm still alive I'm turning him into a strafe rag.

I flew enough BFM against the Raptor before I retired where the new Raptor pilots were discovering there's a time for thrust vectoring and there's a time to leave that club in the bag.
How To Win In A Dogfight: Stories From A Pilot Who Flew F-16s And MiGs

Add to this,
When we induce additional loads on the airframe and on top the TVC module is an added weight and maintenance issues, we are going to increase time in hanger between sorties for checks and also a cost part in maintenance. Also the schedule Time Between Overhauls TBOs has to be in shorter time frame

If you see IAF MKI engines are rated for 4000h service life and yet the mean time between overhaul is reportedly 1,000 hours with a full-life span of 3000h ; the titanium nozzle (TVC Part) has a mean time between overhaul of 500 hours.

This is bcz of the fact that induced loads on airframe and TVC portions suffer from metal fatigue issues which leads to engine related failures.

More can be found in here
Sukhoi Su-30MKI - Wikipedia, the free encyclopedia
 
Ok let me rephrase it in simpler terms
  • MKI uses 3D TVC
  • A 3D TVC uses thurst deflection in both Yaw and pitch axis
  • A 2D TVC uses Thrust deflection in Pitch axis
  • When a 3D TVC uses Thrust to deflect in both Yaw and Pitch, radar waves are more easily bounced off from its surface bcz of which its not preferred in stealthier airframes
  • An example is F22 which uses 2D TVC
Now TVC is not an absolute requirement. Modern jets uses conventional control systems via on wings and tail. But these systems takes space and additional loads are induced on the airframe. Space in wings is already a constraint owing to installation of wing flaps. As for the case of Tails planes, it is a factor of drag inducement and cost for maneuverability and stability. Thus a modern jet without TVC has to have a more of tradeoff based solution for factoring in benefits being offerred by a TVC system

But there are negatives to TVC system too. It basically adds weight, cost and complexity to the aircraft maintenance and operations.
Its benefit in combat is best summarised by this explanation

Is 3D thrust vectoring, like that found on advanced MiG-29 and Su-27 variants, the threat some say it is when it comes to the within visual range fight?

First, a little thrust vectoring history. The USAF tested a 3D nozzle on the Multi-Axis Thrust Vectored F-16 in the early 1990s. It was found that thrust vectoring was really only useful at speeds below 250 knots (with the F-16; the speed will vary with other jets). Above that speed the jet had enough g available and was maneuverable enough that thrust vectoring didn't add anything. Also, at high speeds, if the nozzles start to swing the jet violently around you're apt to induce unacceptable loads on the airframe.

Thrust vectoring, whether 2D or 3D, is a two-edged sword. If you're going to use it, you'd better kill me now. Ever seen videos of the Super Flanker spinning around like a top and doing back flips at an airshow? First off, the jet is slow – not a place to be in a multi-bogey environment. Second, when thrust is steered off-axis the axial component of thrust is decreased. Axial thrust pushes the jet (and wing) through the air at a speed required to maintain lift. Take away forward thrust, take away speed and lift. Go back to the videos. What's happening? The Flanker is dropping like a rock at slow speed (no lift is being produced by the wing). If the Flanker pilot does not kill me now, the other edge of the sword is about to fall. He's automatically building in vertical turning room for me and it's going to take an unacceptable amount of time for him to get enough smash back to take it away due to his low airspeed. If I'm still alive I'm turning him into a strafe rag.

I flew enough BFM against the Raptor before I retired where the new Raptor pilots were discovering there's a time for thrust vectoring and there's a time to leave that club in the bag.
How To Win In A Dogfight: Stories From A Pilot Who Flew F-16s And MiGs

Add to this,
When we induce additional loads on the airframe and on top the TVC module is an added weight and maintenance issues, we are going to increase time in hanger between sorties for checks and also a cost part in maintenance. Also the schedule Time Between Overhauls TBOs has to be in shorter time frame

If you see IAF MKI engines are rated for 4000h service life and yet the mean time between overhaul is reportedly 1,000 hours with a full-life span of 3000h ; the titanium nozzle (TVC Part) has a mean time between overhaul of 500 hours.

This is bcz of the fact that induced loads on airframe and TVC portions suffer from metal fatigue issues which leads to engine related failures.

More can be found in here
Sukhoi Su-30MKI - Wikipedia, the free encyclopedia

Good data, thank you.

So I think as a summary we can say that trust vectoring doesn't actually add to the flying hour cost, but it will add to the maintenancc and repair cost and it could actually be quite significant.

I'll have to disagree there Carlosa mate! There is no such thing as a standard CPFH formula.
The best proof of this is that both the US and France actually use more than one each!

A CPFH is a measurement tool, right? But who is measuring what? Govt or AF?
Your formula is OK for an air force and yet some of them would put modifications aside : ex.
- If the changes happen at program level and retrofit is not done by its maintenance crews.
It doesn't fit govt which is likely to want a more global addition so as not to find treasury surprises.

In France, the AdlA does a lot in-house. That computation of the Rafale CPFH is 14, 000€.
Then you have basic cost computation that amounts to what Pic posted : +- 10 000€.
In mine, any maintenance done by the AdlA is included so that you could call it an OPEX CPFH.
The program CPFH, compounded costs from OEM to Budget ministry is 27 000€ however!
The former is about your version but the latter includes pilots' pay and benefits and infrastructures.
The same is true in America if you compare a USAF CPFH as above or the Congress one.


That is why I asked.

And I missed the convo Parik but not the point! 8-)

Have a great day, Tay.

Thank you, good point. Take care.
 
Originally said the data of CPFH among IAF operated jets in Aero India 2015 held on 16-18 Feb 2015

Picture not very clear but here is the pic

View attachment 298230

According to it as on 2014 end data, (since the Aero India happened in Feb 2016)
  • SU 30 MKI CPFH is USD 12000 for IAF
  • Mirage 2000 CPFH is USD 3000 for IAF

Video on Demand

Check at 1:32:30ish in the video

@Abingdonboy @MilSpec @AUSTERLITZ @scorpionx @nair @Vauban @Taygibay @Picdelamirand-oil

I am sure IAF planners looking at CPFH of Mirage 2000 @3000 USD is most probably hoping to have Rafales CPFH around USD 6000-7000 to keep it around 40-50% cheaper than MKI @12000 USD.

And this is an authentic source.... Now we know why IAF loves French Jets

M2k Is a 95KN AF thrust compared that to 123KN on each engine of the MKI. It is obvious that just the fuel consumption is more than twice considering similar SFC for the engines, in addition, MKI is a larger plane, more subsystems on the plane , more labor hours on ground crew, larger amount of consumables.

By similar logic, LCA 1p operating costs should be quite low too.
 
India's first three women fighter pilots have been advised by the Indian Air Force (IAF) to restrain from motherhood for
the next four years so as not to adversely impact their ongoing training process.
However, IAF sources clarified that the advisory is not legal binding and is to ensure that their training does not get affected.
The three women pilots will be commissioned into the fighter stream on June 18 this year after successful completion of the initial
training.
Thereafter, they would undergo advanced training for one year and would enter a fighter cockpit by June 2017.
"Continuous training is required for a minimum of five years for fighter pilots, men or women, to become combat ready. The three
women are about to complete one year of training," the sources said. Pregnancy means that the entire training schedule gets
disturbed, they added.
"It is not just the cost but the time also that gets affected. Even young fighter pilots are advised not to think about marriage till a
particular age," they said.
Bhawana Kanth, Mohana Singh and Avani Chaturvedi are the trainees who qualified for the fighter stream after it was thrown open to
women in October 2015.
They will go to Bidar in Karnataka in June 2016 for their stage-III training for a year on Hawk advanced jet trainers, before they get to
fly supersonic warplanes.
Six female cadets were competing to become fighter pilots after the government, in a landmark move, approved an IAF plan in
October to induct them as fighter pilots.
However, only three female trainees were selected for the fighter stream.
© India Strategic
 
10955738_714713435292651_5783886409823143929_o.jpg
 
[URL='http://trishul-trident.blogspot.in/2016/03/siva-imr-pod-explained.html']SIVA IMR Pod Explained

In simple terms, the SIVA IMR pod is something similar to the ELTA Systems-developed ELM-2060P radar targetting pod, and it will be used for location of static ground targets/installations. The fact that the DRDO’s PJ-10 Project Office is the nodal agency for developing the IMR pod indicates that this pod will be used in conjunction with the BrahMos-NG (previously known as BrahMos-Mini) air-launched supersonic cruise missile.


While DATA Patterns Pvt Ltd has won the contract to series-produce the BrahMos-NG’s on-board X-band monopulse SAR seeker, the X-band monopulse SAR suite meant for installation inside the IMR pod will be produced by ECIL Ltd.







Contn.......
[/URL]
 
Systems integration and flight qualification of both the BrahMos-NG and SIVA IMR pod will be jointly undertaken by the Indian Air Force’s Bengaluru-based Aircraft & Systems Testing Establishment, HAL’s Nashik Division, BrahMos Aerospace and IRKUT Corp, which is the sole IPR owner of all operating software source-codes used by the Su-30MKI. Service-induction of this weapon system is not expected before 2020.


The existing SIVA HADF pods is used primarily for real-time detection and location of hostile ground-based air-defence radars, with the targetting cues then being uploaded into the Kh-3P anti-radiation missile’s on-board mission computer. This very same pod will in future also be used in conjunction with the DRDO-developed NG-ARM.
 
What do our Indian brothers and sisters think about Iran's possible purchase of the Su-30SM (similar to MKI)? How do they think it would do against Saudi F-15s, bearing in mind that the F-15 is significantly faster and has a better climb rate (speed kills)?

I ask because I know you are bound to be highly knowledgeable on this aircraft.

Thanks in advance.
 
What do our Indian brothers and sisters think about Iran's possible purchase ogivese Su-30SM (similar to MKI)? How do they think it would do against Saudi F-15s, bearing in mind that the F-15 is significantly faster and has a better climb rate (speed kills)?

I ask because I know you are bound to be highly knowledgeable on this aircraft.

Thanks in advance.

Well not much difference in the capabilities of both. All boils down to the pilot and maybe the radar and IRST system of Flanker gives it an edge over F15.
 
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