Pakistan will launch a two-seater version of JF-17 - Induction of JF-17B in 2017

[volatile]

F16 Canopy is also two piece and with clever piece of Engineering its the opposite on any fighter we see e.g

Part A will be at front e.g

and for many other fighters ,F16 comes with a bird slicer at front if im correct ,Any one care to explain what's the limitation for putting B part at front

 

[MastanKhan]

F16 Canopy is also two piece and with clever piece of Engineering its the opposite on any fighter we see e.g
View attachment 329829
Part A will be at front e.g
View attachment 329831
and for many other fighters ,F16 comes with a bird slicer at front if im correct ,Any one care to explain what's the limitation for putting B part at front

View attachment 329836

Hi,

Stress fracture---distortion---flexing. That is why you see the same setup on the J20---.

With the available technology---for the JF 17 that is the best setup---.

Just loo at this---how big the canopy is on the F16 dual seater.

 

[krash]

F16 comes with a bird slicer at front if im correct

That's just a nickname given to the IFF (Identification Friend-or-Foe) antennae at the front. Their purpose doesn't actually include slicing birds. Also, they aren't present on all the different versions of the F-16.

 

[amardeep mishra]

That's just a nickname given to the IFF (Identification Friend-or-Foe) antennae at the front. Their purpose doesn't actually include slicing birds. Also, they aren't present on all the different versions of the F-16.

Hi @krash
Apart from being IFF,just by their design,i tend to think they can also generate very strong vortices just behind them,so that the flow remain attached to the surface of the bubble canopy. 4 very powerful vortices will energize the flow over bubble canopy thereby creating strong suction regions. I like the arrangement and design of IFF in this particular F-16 model

 

[krash]

Hi @krash
Apart from being IFF,just by their design,i tend to think they can also generate very strong vortices just behind them,so that the flow remain attached to the surface of the bubble canopy. 4 very powerful vortices will energize the flow over bubble canopy thereby creating strong suction regions. I like the arrangement and design of IFF in this particular F-16 model

That is a very interesting thought. Would you reckon that the vortices would be strong enough to 'deflect' large birds at such speeds? Intrigued by the nickname myself, I remember trying to search something about it online but all I found was that they were just antennae.

 

[amardeep mishra]

That is a very interesting thought. Would you reckon that the vortices would be strong enough to 'deflect' large birds at such speeds? Intrigued by the nickname myself, I remember trying to search something about it online but all I found was that they were just antennae.

Hi dear @krash
I was talking more in terms of their physical design-aerodynamic considerations of such a structure. I am sure you would have heard of "strakes"?These are small edged structures that are attached to certain regions of planes(now-a-days in sports cars as well!) to generate strong vortices. I mean strictly speaking any "finite wing" will generate vortices and if that vortex happens to pass just over any surface then it transfers some of itz energy to the boundary layer in contact with that surface over which this vortex is flowing. This added energy(velocity) to the boundary layer in contact with this surface further reduces the pressure-bernoulli's principle in action here-thereby creating more lift or increasing what is known as Clmax!
Practically an IFF antenna in the shape of a strake just before canopy would ensure that the flow remain attached to the canopy even at high AoA.
As for it being able to "slice" birds,i think thats because the typical shape of a strake.It looks like a slicer lol

 

[krash]

Hi dear @krash
I was talking more in terms of their physical design-aerodynamic considerations of such a structure. I am sure you would have heard of "strakes"?These are small edged structures that are attached to certain regions of planes(now-a-days in sports cars as well!) to generate strong vortices. I mean strictly speaking any "finite wing" will generate vortices and if that vortex happens to pass just over any surface then it transfers some of itz energy to the boundary layer in contact with that surface over which this vortex is flowing. This added energy(velocity) to the boundary layer in contact with this surface further reduces the pressure-bernoulli's principle in action here-thereby creating more lift or increasing what is known as Clmax!
Practically an IFF antenna in the shape of a strake just before canopy would ensure that the flow remain attached to the canopy even at high AoA.
As for it being able to "slice" birds,i think thats because the typical shape of a strake.It looks like a slicer lol

Haha glad we cleared that out, I was a bit sceptical about the slicing bit :p

Squeezing in the bernoulli's effect wherever can be makes good sense (short of making it a flying wing design) but during fast high AoA manoeuvres wouldn't the generated vortices be more pronounced and hence at least somewhat clearly visible passing over the canopy? Like they are over the wings when generated from the LERX? I've tried finding evidence of it but to no avail,

But then again, the vortices generated from the outboard trailing edges aren't always visible either. In such a case wouldn't the low pressure generated by these minuscule vortices be negligible?

 

[volatile]

Hi,

Stress fracture---distortion---flexing. That is why you see the same setup on the J20---.

With the available technology---for the JF 17 that is the best setup---.

Just loo at this---how big the canopy is on the F16 dual seater.

Yes ,I deliberately didn't dare to put dual seat picture as that canopy is real piece of Engineering .

 

[amardeep mishra]

Squeezing in the bernoulli's effect wherever can be makes good sense (short of making it a flying wing design) but during fast high AoA manoeuvres wouldn't the generated vortices be more pronounced and hence at least somewhat clearly visible passing over the canopy? Like they are over the wings when generated from the LERX? I've tried finding evidence of it but to no avail,

Hi @krash
Yes indeed bernoulli's effect is what generates the pressure differential across the top and bottom surface of the "finite wing".It is this pressure differential again that pushes the circulation of air from higher pressure at bottom to low pressure at top giving rise to "vortices". I mean in a continuous flow along the chord of the wing,if you take two points 1 and 2,top and bottom of the wing respectively and apply the bernoulli(which is essentially a conservation principle)-
P1+0.5*rho*v1^2+rho*g*h=P2+0.5*rho*v2^2+rho*g*h.
this can be re-written as P2-P1=0.5*rho(v1^2-v2^2)=delta(P)----------------1
Eqn 1 is very crucial and relates the difference in velocity to difference in pressure.Now the velocity of air moving over the wing is higher than the air moving below it because of the camber- the air over it has to travel longer distance in same amount of time! So by increasing the camber you also increase the pressure differential.
But how do you increase the camber?- by control surfaces!
We also know that water boils at a lesser temperature if the surface pressure is low.Now if by some means you can bring down the pressure over the wings,you can boil water(from atmosphere) at normal ambient temperature! THats what essential happens when you see that white smoke trail from the LERX in f-16!
In picture above,i.e F-16 with large LERX,you can clearly see a very strong vortex over the wing- itz effect is similar to lets say the compound delta you find in LCA!- in both these cases,these wing portions help in pushing flight envelop by increasing Clmax- or the max allowable AoA before the wing stalls!
In case of LCA though,in sub-sonic regime as we increase the AoA,the comound delta structure- double angle at the leading edge section of the wing- helps in creating vortex in a much controlled fashion thereby reducing the total drag!
The stronger vortex generation you can render,more will be your evaporation. The strakes on the other hand are not big enough to create such strong vortices- although a group of small strakes can generate small vortices that definitely helps in keeping flow attached over the canopy!

 

[Bratva]

In my controversial opinion. Developing JF-17 B is akin to wasting your resources time and dedication. JF-17B would be based on block-2 costing 20-25 Million a piece. It would have a limited utility and small buyer base because of its price when it comes out in 2017.

A smart path was to put your resources into JL-10 development and customization. Because multiple african countries have already purchased JL-10 aka L-15. There is nothing JL-10 cant do what JF-17 can do. Recent Up-gradations in JL-10 engine avionics and PESA Radar, E/O sensors and weapon integration has made it surpass Block-1 in many aspects and is at par with JF-17 block-II .

JL-10 would have cost 10-15 million in the end and by inducting JL-10 we could have phased out our K-8P Thus by JL-10 saving us money not only on JF-17B development cycle with little return but also would had saved our time and resources in buying a new platform to replace K-8P and not mention its commonality with JF-17, not only the similar avionics and weapons, but we could have added customized EW and Data link systems on it so that Newbies who starts their flying careers learn from the get go about the advance technologies

Can K-8P do all the things JL-10 do No it cant. JL-10 would had been a complete bang for bucks. But I dont know what goes into the minds of PAF planners. @MastanKhan @RAMPAGE @Arsalan @HRK @Oscar

 

[Deino]

@Bratva
I think You are not correct: the JL-10 is a trainer - in the current JL-10-form not even a supersonic one at least not comparable to the JF-17 - its weapons load is smaller, has less range and I'm sure since it is a dedicated trainer at first, flight performance is at least different - IMO surely not on par - with the performance a JF-17 has. Also the PESA has only a small diameter, so radar performance shouldn't be comparable.

It surely has its pros - esp. price - for many coulntries ... but it is surely not a dedicated multirole fighter like the JF-17.

Just my 2 cents,
Deino

 

[Tipu7]

In my controversial opinion. Developing JF-17 B is akin to wasting your resources time and dedication. JF-17B would be based on block-2 costing 20-25 Million a piece. It would have a limited utility and small buyer base because of its price when it comes out in 2017

Jf17B is developed to full fill export demands.
Probably first three air crafts will be bought by Nigeria who requested for enhanced ground strike package.
Jf17B is not only a LIFT, but also a multirole fighter with same capabilities as Jf17A with range as exception. It will be active part of squadrons.PAC can Develop dedicated ECM or Ground strike air craft out of it.

There is nothing JL-10 cant do what JF-17 can do.

How about carrying CM400 AKG? Or C802? Mar1? Will it be able to integrate weapon package which will be introduced in Blk3 ?

JL-10 would have cost 10-15 million in the end and by inducting JL-10 we could have phased out our K-8P Thus by JL-10 saving us money not only on JF-17B development cycle with little return but also would had saved our time and resources in buying a new platform to replace K-8P and not mention its commonality with JF-17, not only the similar avionics and weapons, but we could have added customized EW and Data link systems on it so that Newbies who starts their flying careers learn from the get go about the advance technologies

I doubt about similar avionics and weapons part.

Can K-8P do all the things JL-10 do No it cant. JL-10 would had been a complete bang for bucks. But I dont know what goes into the minds of PAF planners.

Why you want K8 to do all the things which JL10 can do?
And yara plz, PAF planners did the right thing to go for twin seater ......

 

[Bratva]

@Bratva
I think You are not correct: the JL-10 is a trainer - in the current JL-10-form not even a supersonic one at least not comparable to the JF-17 - its weapons load is smaller, has less range and I'm sure since it is a dedicated trainer at first, flight performance is at least different - IMO surely not on par - with the performance a JF-17 has. Also the PESA has only a small diameter, so radar performance shouldn't be comparable.

It surely has its pros - esp. price - for many coulntries ... but it is surely not a dedicated multirole fighter like the JF-17.

Just my 2 cents,
Deino

There is no sizeable increase in the dimensions of dual-seater. Which means Dual seater will have less fuel as compare to single seater. So Dual seater will have a less range than single seater. Dual seater is coming with same number of hard points. PAF slogan from the get go is they dont need dual seater. PAF has 70+ JF-17 without any dual seater. Which means they dont have any immediate requirement for the dual seater.

Now for the weapons. Dual seater will not offer any significant advantage over single seater because both are sharing same things. And since 70 single seater JF-17's have trained much in multi role aspects that It can be said with certainity that it is a good compromise that PAF can live without Dual seater JF-17.

Hence what I suggested in the original post that Customization has to be done for JL-10 if PAF wants it


So what my original post tried to convey was that JL-10 is an excellent tradeoff. Target market of dual seater JF-17 is very very dim. African nations are already buying JL-10. They will go for a much cheaper option than Dual seater JF. So why waste resources on a product which will not be used in great numbers in PAF and will not be bought by customers in the long run ?

Jf17B is developed to full fill export demands.
Probably first three air crafts will be bought by Nigeria who requested for enhanced ground strike package.
Jf17B is not only a LIFT, but also a multirole fighter with same capabilities as Jf17A with range as exception. It will be active part of squadrons.PAC can Develop dedicated ECM or Ground strike air craft out of it.

How about carrying CM400 AKG? Or C802? Mar1? Will it be able to integrate weapon package which will be introduced in Blk3 ?

I doubt about similar avionics and weapons part.


Why you want K8 to do all the things which JL10 can do?
And yara plz, PAF planners did the right thing to go for twin seater ......

Continuing from the reply given to Deino. This is the catch. JF-17B is targeted for which customers ? Because customers are scarce for JF and correct me If I'm wrong. Dual seater cost more than the single seater. JF-17 export customers are 3rd world countries. So why do they need dual seaters when they can practice on JL-10 for air-2-air, air-2-Ground combats and then can transition on to JF-17 ? Multiple african countries has purchased JL-10.

And for being active part of PAF. I will remain skeptical. A air-force who is claiming from the get go they dont need dual seaters will develop a dedicated ECM or ground strike of it ? Single seaters have perfected the art of dedicated ground strike. I dont see any reason why would they need dedicated ground strike of JF.

What is the benefit of attaching CM-400 C802 or MAR-1 on an aircraft whose range would be reduced because of adding an extra seat ? which again begs the question. A lesser range aircraft carrying ground strike package will add a benefit in combat how ?

Similar avionics and weapons in a sense that Customers can practive PGM, GPS_Guided, HOBS missile, BVR on JL-10 and then easily transition on JF-17. Isnt business models run on tradeoffs ?

 

[MastanKhan]

There is no sizeable increase in the dimensions of dual-seater. Which means Dual seater will have less fuel as compare to single seater. So Dual seater will have a less range than single seater. Dual seater is coming with same number of hard points. PAF slogan from the get go is they dont need dual seater. PAF has 70+ JF-17 without any dual seater. Which means they dont have any immediate requirement for the dual seater.

Now for the weapons. Dual seater will not offer any significant advantage over single seater because both are sharing same things. And since 70 single seater JF-17's have trained much in multi role aspects that It can be said with certainity that it is a good compromise that PAF can live without Dual seater JF-17.

Hence what I suggested in the original post that Customization has to be done for JL-10 if PAF wants it


So what my original post tried to convey was that JL-10 is an excellent tradeoff. Target market of dual seater JF-17 is very very dim. African nations are already buying JL-10. They will go for a much cheaper option than Dual seater JF. So why waste resources on a product which will not be used in great numbers in PAF and will not be bought by customers in the long run ?

Hi,

In this day and age----it is very difficult to introduce a new aircraft for sale in a market dominated by superpowers.

So---in order for you to be successful---you have to cover all corners. That is what the JF17B will do---. It was an error in the original decision making process---what is happening now is to cover up that blunder.

Now---when you already have a successful product---the buyers also want a twin seater of that single seater aircraft---then it would not be very intelligent to offer a JL - 10.

That would be like opening another can of worms----.

 

[Bratva]

Hi,

In this day and age----it is very difficult to introduce a new aircraft for sale in a market dominated by superpowers.

So---in order for you to be successful---you have to cover all corners. That is what the JF17B will do---. It was an error in the original decision making process---what is happening now is to cover up that blunder.

Now---when you already have a successful product---the buyers also want a twin seater of that single seater aircraft---then it would not be very intelligent to offer a JL - 10.

That would be like opening another can of worms----.

Well why would customer buy a 25-30 million dual seater JF-17B and spend more on it to maintain it when he can buy a 10-15 million JL-10. Practice A-2-A, A-2-G combats. Will cost less to maintain JL-10 and then pilot can transition on to single seater JF-17 ?