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JF-17 Thunder Multirole Fighter [Thread 6]

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In my humble opinion there ars multiple disadvantages in going down this route. Firstly you need to clear the ambiguity around what exactly you want. Our conversation started with EJ2000 engines for JFT. Then it was proposed that adding the EJ2000 engine would convert it into a medium weight fighter (+ weight reduction with composites). Now we have a hypothetical replacement fighter for the 16s. It seems to me and please correct me if I am wrong that your goal posts are changing.
Let us first set our criteria for discussion.
A. A replacement medium weight fighter for the 16s like JFT.
B. How many squadrons as this will have a bearing on costs
C. Commonality of characteristics ---a problem or not?
D. Can PAF/GOP sustain two projects simultaneously or not.
E. What is the proposed outcome for the cureent JFT--ie project completed or continuing.
Current engine strength of RD 93 Iis 19600 lbs which might be a bit more than the 84 KN you have quoted.
Lets get our criteria set and please feel free to change any of the criteria and then we can talk
Kind regards.
Lets call this hypothetical fighter PFX.

A. Not exactly a replacement but an alternative to buying further F-16s from US. Induction of PFX to increase the number of medium weight fighters to a minimum of 110.

B. You're looking at 2 squadrons of PFX. More units can be ordered if required. R&D costs will be minimum due to the minimum alterations required to install EJ2x0. Composites are most probably planned for JF-17's future variants so no additional R&D costs there.


C. No.

D. Not exactly a different program as the only difference will be a different engine and alterations to the rear fuselage.

E. Continues as planned.
 
120 - 84.4 = 35.6

That is 35.6 KN of additional thrust. Not to mention that the empty weight of JF-17 is much less than F-16 C/D block 52.It will be further reduced by using composites.

Just to butt in on the debate a tiny bit but what you have claimed is too generous.

If you add 35.6 kN of additional thrust it goes without saying you will be ADDING weight as well because such a dramatic increase in thrust WILL require rather extensive strengthening of the structure. So sure adding a higher thrust engine could be a future path for the JF-17 but don't expect to increase thrust by 40% and expect the T/W to increase by 40% as well. Just keep in mind your weight will increase significantly, probably even if you are switching to more and more composites.
 
OK mastan bahi what should I belief here are your two 180 degree out of phase quotes ..... do not mean any offense .... but how do you define yourself ..... a change of heart or some involvement of people from ME caused this @MastanKhan

Hi,

A new engine for the JF 17 is a must---the engine must have FADEC---full authority digital engine control---that in itself would be a massive fuel saver---will give it at least 1 1/2 time the flying time if not double and more power.

As the JF17 design is modular---it has the capacity built in to utilize engines of the same class with minimal modifications---that was planned during the design.

Because at that time---the engine was an issue---chinese engine was not ready---.

Now I believe that the EJ200 is smaller than the RD93 and a little lighter as well---and even the chinese engine.

So better thrust to weight ratio---better fuel mileage---lighter in weight----better acceleration---shorter spool up time.

Just want to let you new guys know---the current JF17 at kamra---and a SU30 at srinagar airbase---if the JF17 is taking off from kamra---a sortie of 2 JF17's will be in the air at striking distance of the airfield in srinagar even before the SU30 takes off.

and from under mentioned thread

Source: Pakistan to stick with RD-93 engine for JF-17, say PAF officials

"
Hi.

That tells you that the RD93 is the right engine for his aircraft and it was the right engine from day one. The issue about the power are not technical in nature but just for the armchair bandits----blowing bubbles.

This is not a race of who is faster from 0 to 60---but the race is for endurance---utility---availability---ease of servicing and reliability.

Young pakistanis must learn and realize that in weapons of war---you do not go out for glittery and shinny stuff--but you go for the known and proven---.

This is not a dash for a 100 meters race---but this is sustenance for a marathon---so your utility needs to be suitable for the marathon.

We also find out that the smoke issue is also secondary---and there is no big deal about it----it was just a drama created by the critics who could not find anything else wrong with it.

"

please elaborate .....
 
One thing that is being repeatedly quoted is that restructuring will add weight, but the thing is that EJ200 is not only lesser in diameter but also some 70 odd KG lighter. This will allow increased room for avionics and structural reinforcement. Although the weight might increase but still better thrust and fuel optimization will pay off in longer run. It can also free up space for greater fuel storage for longer sortie.

Just my thoughts
 
OK mastan bahi what should I belief here are your two 180 degree out of phase quotes ..... do not mean any offense .... but how do you define yourself ..... a change of heart or some involvement of people from ME caused this @MastanKhan



and from under mentioned thread

Source: Pakistan to stick with RD-93 engine for JF-17, say PAF officials

"
Hi.

That tells you that the RD93 is the right engine for his aircraft and it was the right engine from day one. The issue about the power are not technical in nature but just for the armchair bandits----blowing bubbles.

This is not a race of who is faster from 0 to 60---but the race is for endurance---utility---availability---ease of servicing and reliability.

Young pakistanis must learn and realize that in weapons of war---you do not go out for glittery and shinny stuff--but you go for the known and proven---.

This is not a dash for a 100 meters race---but this is sustenance for a marathon---so your utility needs to be suitable for the marathon.

We also find out that the smoke issue is also secondary---and there is no big deal about it----it was just a drama created by the critics who could not find anything else wrong with it.

"

please elaborate .....

Hi,

Thank you for asking----. In major weapons systems----you need to attain stability in a platform to take you to a certain pleteau---so that your requirements and usage is managed and maintained optimally at the highest possible standard for that machine.

So---the RD93 has reached that standard awhile ago---and there are what----around 75 examples of aircrafts flying with this engine.

Now as with all fighter aircrafts---once a successful block has been established---the work goes onto build the next block with more features and better power plant---and that is all that is happening with the JF17---.

With the success of the program---you also may have much better equipment available to enhance the capabilities of your machine---and that is what is happening at this time.

The RD93 has reached its maximum potential---to take the aircraft to the next level you need an engine with FADEC---

Google

I have posted a link to multiple websites-----which explains what fadec does.

To give a car example---the RD93 is like a carburator engine----the fadec engine is fuel injection engine.

In automobiles---when the fuel injection first came in---the difference in HP immediately jumped by 20% just by replacing a carburator with a fuel injection system---the gas mileage got better and when the fuel imjection changed from continuous fuel injection to metered fuel injection---there was another increase in fuel mileage and HP---and when the fuel injection changed over to direct fuel injection for gasoline engine----the HP jumped up further on the same engine with better gas mileage---.

So---the HP difference in a carburator engine and direction fuel injection engine would be like

Carburator engine 100 HP

Direct Injection engine 150---180 HP---for the same engine---but now the problem is that the old engine cannot handle that much power----so you need a new block---crankshaft---cam shaft---pistons and rings to handle that much more power.
 
Just keep in mind your weight will increase significantly, probably even if you are switching to more and more composites.
Are you sure about this?

Still, The empty weight of JF-17 is almost 1700 kg less than the F-16 C/D blk 50/52.

Will it still not be able to match blk 50/52 in MTOW and combat radius?

@Danish Moazzam What do you think?
 
One thing that is being repeatedly quoted is that restructuring will add weight, but the thing is that EJ200 is not only lesser in diameter but also some 70 odd KG lighter. This will allow increased room for avionics and structural reinforcement. Although the weight might increase but still better thrust and fuel optimization will pay off in longer run. It can also free up space for greater fuel storage for longer sortie.

Just my thoughts
You cant just add thrust without strengthening the air frame for it. Strengthening means additional weight. This was what JamD pointed out.
A
 
Hi,

Thank you for asking----. In major weapons systems----you need to attain stability in a platform to take you to a certain pleteau---so that your requirements and usage is managed and maintained optimally at the highest possible standard for that machine.

So---the RD93 has reached that standard awhile ago---and there are what----around 75 examples of aircrafts flying with this engine.

Now as with all fighter aircrafts---once a successful block has been established---the work goes onto build the next block with more features and better power plant---and that is all that is happening with the JF17---.

With the success of the program---you also may have much better equipment available to enhance the capabilities of your machine---and that is what is happening at this time.

The RD93 has reached its maximum potential---to take the aircraft to the next level you need an engine with FADEC---

Google

I have posted a link to multiple websites-----which explains what fadec does.

To give a car example---the RD93 is like a carburator engine----the fadec engine is fuel injection engine.

In automobiles---when the fuel injection first came in---the difference in HP immediately jumped by 20% just by replacing a carburator with a fuel injection system---the gas mileage got better and when the fuel imjection changed from continuous fuel injection to metered fuel injection---there was another increase in fuel mileage and HP---and when the fuel injection changed over to direct fuel injection for gasoline engine----the HP jumped up further on the same engine with better gas mileage---.

So---the HP difference in a carburator engine and direction fuel injection engine would be like

Carburator engine 100 HP

Direct Injection engine 150---180 HP---for the same engine---but now the problem is that the old engine cannot handle that much power----so you need a new block---crankshaft---cam shaft---pistons and rings to handle that much more power.



thanx for the detail ..... I have gone through the RD33MK on which I assume that RD93ma was to be based upon and it does have FADEC and the description matches your definition above ..... so why EJ200 and why not RD93ma as speculated earlier along with news of setting up facility for overhauling ......... is it owing to the stage-2 upgrade of EJ200 which provides 120KN thrust and RD93ma is said to have around 98KN (as I rememeber) or some other factor "POLITICAL" involved .... may be some customer want similarity with existing fleet engines
 
One thing that is being repeatedly quoted is that restructuring will add weight, but the thing is that EJ200 is not only lesser in diameter but also some 70 odd KG lighter. This will allow increased room for avionics and structural reinforcement. Although the weight might increase but still better thrust and fuel optimization will pay off in longer run. It can also free up space for greater fuel storage for longer sortie.

Just my thoughts

Hi,

In the automotive industry some cars and trucks are designed for 4 and 6 cyl engines and some are designed for 6 and 8 and 10 cyl engines right from the gitgo.

Like a dodge ram truck or a ford truck or cargo van----the suspension would be of a heavier duty on the larger engine---.

I would 'assume' that some of the concerns of a higher output engine would already had been figured out in the initial design----because the supposed chinese engine was in the development stage---so the chasis / frame would have to be designed originally to take on the more powerful power plant----.

I mean to say---that is basic engineering 101----. If the paf failed to do that---then you got serious issues.

Now to the engine issue----american and european engines have a much longer life span---and a much better fuel consumption---the reliability level is pretty high---.

Then it also comes to marketing----some nations are already pre-sold on the equipment of certain countries and they won't change their minds---and to others you can coax them.

So---your product needs to have international appeal and that is what the JF17 product is headed towards.
 
Are you sure about this?

Still, The empty weight of JF-17 is almost 1700 kg less than the F-16 C/D blk 50/52.

Will it still not be able to match blk 50/52 in MTOW and combat radius?

@Danish Moazzam What do you think?
I am not entirely sure hence the use of the word probably but it is my guesstimate. 40% increase is thrust is huge from a structural standpoint

Just to be clear you won't just be strengthening the mounts but also the wing structure and the empenage. I mean the whole point of adding more thrust was to aircraft to do more aggressive things right?

I'm just saying suddenly putting in an engine with so much more thrust seems like a bad adhoc solution. To use a car example corolla main 6 litre v12 lagana lol.

I hate to talk in absolutes so I will just say what I think is the smart play here. I think it is best to stick with the RD-93 and get something like an RD-93MA upgrade or something. Change the least number of things to get the most advantage. Get better fuel economy and maybe 5 to 10 % more thrust. I would be a very happy man if we could do this by simply upgrading the same engine somehow. Of course you would still need some structural strengthening but nothing as dramatic as you would need for let's say 40% increase in thrust.
 
I agree, stick to RD-93 and upgrade to MA. get local 100% support capability to avid any sanctions. increaes couple of hardpoints and may be that is it.
definitely upgrade avionics to EOTS, AESA, ECCM etc.
 
Lets call this hypothetical fighter PFX.

A. Not exactly a replacement but an alternative to buying further F-16s from US. Induction of PFX to increase the number of medium weight fighters to a minimum of 110.

B. You're looking at 2 squadrons of PFX. More units can be ordered if required. R&D costs will be minimum due to the minimum alterations required to install EJ2x0. Composites are most probably planned for JF-17's future variants so no additional R&D costs there.


C. No.

D. Not exactly a different program as the only difference will be a different engine and alterations to the rear fuselage.

E. Continues as planned.
OK!?Lets get the facts out on the board.
Max thrust of RD 93 currently as per recent interview of project director of JFT is 19600 lbf.
Max thrust of EJ200 Series engines is 100kn (20000lbf).
So what we are looking at is an engine which has 400lbf more thrust, has significantly better MTBO but is 5 million more expensive if not more.
RD93MA is round the corner with fadec and better MTBO and the same thrust as EJ200 series. It may be a couple of million more expensive but with PAF having infrastructure available for over hauling RD93 series the infrastructure could be utilized to save a lot of costs.
If we agree to the facts mentioned above then lets move on to analysing our remit.
A. Designing an alternate to buying more 16s.
F16s come not only with increased range and payload but also with other hardware which is where we have huge problems countering/manufacturing. The Goodrich recce pod is a classical example. The fighter you are proposing to build will take too much time and for the money PAF will probably get its target of 110 fighters with a combination of new and MLUed platfor and the acquisition will be complete most likely by 2019-20.
So where we can improve JFT is by increasing at least 3 more hardpoint one for a POD on the chin inlet and 2 more on the wings. More composites might mean a bit more weight loss which might translate into ability to carry more fuel thereby increasing range in conjunction with a better performing engine. This is in my humble opinion achievable on the current airframe with a slightly better engine. Other alternative is to relocate the gun and use both chin inlets for hardpoints which will be a lot more fiddly. The last option is to think along the lines of CFT freeing up the 3 hardpoints. Or only one central tank plus 2 hardpoints. Combine that with a chin inlet and you have a pretty good fighter.
These are achievable points on the curent airframe with very little or few modifications.
Now if we lengthen or enlarge the airframe that will need retesting and moe money which we dont have. Just to give you an example the IFR probe installations and testing has taken at least 12_-15 months.
The other point to consider is that we are at the transition phase between generations. If you now waste another 3-5 years on researching and then another couple of years manufacturing the platform then you have lost the purpose of the platform.
The last thing I would say is that in order to develop a middle weight fighter you will have to rely on the Chinese as your developmental capabilities are infantile at best. Would they want to create competition for theJ10 in the market? They would much rather we bought 2xsq. J10s
So in my view it is possible to make incremental changes to JFT ala F16 to incrementally develop its capabilities in blocks depending on what capabilities are available at the time. Do we transform the JFT at some stage to a heavier fighter like the C&°D examples of 16s remains to be seen. The factors are the needs of PAF,fighter demands in the market and the finances available. We have suffered more from the last angle than most other factor. We have a very gòod airframe that not only suites our needs but is an aerodynamic wonder. The thing to do is increase its capabilities depending on resouces available at the time.
One of the problems with theFF35 has been that it has been tweeked tò bethe be all aand know all of all the fighters to such an extent that it is fast becoming a liability rather than an assett. We dont want to go down that route with what has worked beautifully for us.
The world of hypothesis is always good to keep the brain in gear but always remember the old adage" the enemy of good is better".
A
 
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OK!?Lets get the facts out on the board.
Max thrust of RD 93 currently as per recent interview of project director of JFT is 19600 lbf.
Max thrust of EJ200 Series engines is 100kn (20000lbf).
So what we are looking at is an engine which has 400lbf more thrust, has significantly better MTBO but is 5 million more expensive if not more.
RD93MA is round the corner with fadec and better MTBO and the same thrust as EJ200 series. It may be a couple of million more expensive but with PAF having infrastructure available for over hauling RD93 series the infrastructure could be utilized to save a lot of costs.
If we agree to the facts mentioned above then lets move on to analysing our remit.
A. Designing an alternate to buying more 16s.
F16s come not only with increased range and payload but also with other hardware which is where we have huge problems countering/manufacturing. The Goodrich recce pod is a classical example. The fighter you are proposing to build will take too much time and for the money PAF will probably get its target of 110 fighters with a combination of new and MLUed platfor and the acquisition will be complete most likely by 2019-20.
So where we can improve JFT is by increasing at least 3 more hardpoint one for a POD on the chin inlet and 2 more on the wings. More composites might mean a bit more weight loss which might translate into ability to carry more fuel thereby increasing range in conjunction with a better performing engine. This is in my humble opinion achievable on the current airframe with a slightly better engine. Other alternative is to relocate the gun and use both chin inlets for hardpoints which will be a lot more fiddly. The last option is to think along the lines of CFT freeing up the 3 hardpoints. Or only one central tank plus 2 hardpoints. Combine that with a chin inlet and you have a pretty good fighter.
These are achievable points on the curent airframe with very little or few modifications.
Now if we lengthen or enlarge the airframe that will need retesting and moe money which we dont have. Just to give you an example the IFR probe installations and testing has taken at least 12_-15 months.
The other point to consider is that we are at the transition phase between generations. If you now waste another 3-5 years on researching and then another couple of years manufacturing the platform then you have lost the purpose of the platform.
The last thing I would say is that in order to develop a middle weight fighter you will have to rely on the Chinese as your developmental capabilities are infantile at best. Would they want to create competition for theJ10 in the market? They would much rather we bought 2xsq. J10s
So in my view it is possible to make incremental changes to JFT ala F16 to incrementally develop its capabilities in blocks depending on what capabilities are available at the time. Do we transform the JFT at some stage to a heavier fighter like the C&°D examples of 16s remains to be seen. The factors are the needs of PAF,fighter demands in the market and the finances available. We have suffered more from the last angle than most other factor. We have a very gòod airframe that not only suites our needs but is an aerodynamic wonder. The thing to do is increase its capabilities depending on resouces available at the time.
One of the problems with theFF35 has been that it has been tweeked tò bethe be all aand know all of all the fighters to such an extent that it is fast becoming a liability rather than an assett. We dont want to go down that route with what has worked beautifully for us.
The world of hypothesis is always good to keep the brain in gear but always remember the old adage" the enemy of good is better".
A
Thank you for the replies, Sir. The points you raise are not without merit. Lets leave it at that.
 
In the beginning at this forum it was greatly annoying but with the passage of time it got funny. I am talking about the "expert reviews" coming from mouths that still got "feeders"(technically speaking).
For example a person summed it up like that "EJ-200 has only 400 lbf higher thrust and FADEC with a bit better MTBO than RD-93 and the MA variant of the Russian engine will more likely cover that distance too", simply hilarious :tup:
Now it would be childish for me to go through the vast details being repeated over and over again so let me simply put it that you people are comparing the lowest(in every regard) turbofan available with the best in this class. And for getting some genuine info about early and modern, vastly used turbofans you should go through this article. And by the way RD-33 is not even mentioned here and instead AL-31 and izdelyi117 are given as a comparatives examples from Russian engines.
Fighter aircraft engine comparision « Defense Issues
MastanKhan I salute your strength of heart for answering each and every of these "experts", despite the fact that they don't even deserve it.
We will simply be only quenching our "technical enthusiasm" here but the main factor will remain untouched. From day first the choices of the decision makers were out of sense. From early 2000's the MK variant of RD-33 was in production and RD-93 could have been easily converted to this standard upon proper diplomacy without adding significantly to the unit cost but with advantages of higher thrust, increased reliability & MBTO, no smoke, and FADEC as well. But surprisingly even yet the focus is just on increasing a few hundred pounds of wet thrust which in the end means nothing if the dry thrust remains the same. The Chinese engine will also be no different story even if it gets operational in next "may be 5 years" cuz it's based on the same 40 years old design.
So the bottom line will still be a need for an engine that will not only give JF-17 the punch and primness it lacks and will also be a better dependable option in case of going for a fifth gen twin engine fighter. And EJ-200 is the most favorable choice in this regard with points of being the best in its class in every technical and performance based area, less prone to sanctions comparing to US options and especially when Turkey is also going to induct it for its TFX , making it more in reach.
And I am tired.
 
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In the beginning at this forum it was greatly annoying but with the passage of time it got funny. I am talking about the "expert reviews" coming from mouths that still got "feeders"(technically speaking).

MastanKhan I salute your strength of heart for answering each and every of these "experts", despite the fact that they don't even deserve it.

I hope you wouldn't let your emotions get the better of you in the future. Condescension never helped anyone's argument. If anything it is a perfect way to make your own argument weaker. We should try to stay unemotional and civil :)
 
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