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JF-17 Thunder Multirole Fighter [Thread 7]

CFT is a very simple thing. First designed by Israeli conception. There is no magic to it. We have half-witted people here who don't know what they are talking about, making bland statements when they dont know jack about anything.

This is a sad mindset. Instead of trying to learn and grow, these fellows can neither learn nor help others gain anything other than their garbage. This garbage then creates more garbage minds.
While I agree with your post, I don't think CFT is as simple as you are making it out. From the top of my head I can think of a few factors that would have to be considered for its design.

1. Aerodynamics of the CFT itself
2. Reduced aerodynamics/lift factor of the wings
3. Added load on the wing structure
4. Dynamic loading due to the fuel inside sloshing around
 
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Why would it be negligible?
We don't know what design and size Thunder CFT's would be but using the same ratio as for F-16, Thunder CFT's would be about 60% of the underwing tanks, and then underwing pylons would carry additional armaments so the impact on the range would be quite significant i,e. less fuel, more drag due to CFT's (howsoever negligible, it won't be zero) and then the additional weight of underwing armament.

F-16:
Internal 7,160lbs
CFTs 3,000lbs (36% of underwing)
Centerline 2,045lbs
Underwing 8,180lbs

Thunder:
Internal 5,130lbs
CFT's 463lbs (36% of underwing)
Centerline 467lbs
Underwing 1,286lbs
What?
Use of F16s underwing and centerline fuel carrying capacity here is not relevant.

Wouldn't the only thing relevant be the capacity of fuel tanks currently being carried by JF17 vs the fuel carrying capacity of potential CFTs on JF17?

It is the difference between the two that we are interested in. Currently(according to wikipedia)...the JF17 optionally carries an 800 Kg(1764 lbs) fuel tank on the centerline hardpoint...
...while the two underwing fuel tanks can be either the 800 Kg(1764 lbs) or 1100 Kg(2425 lbs).

So if instead of the two underwing hardpoints carrying fuel tanks...the two CFTs are to carry it...then we will need to know the capacity of the supposed conformal fuel tanks of JF17...which don't yet exist...hence why I had used F16 as an example here. The reason for using F16...as opposed to some other aircraft is that F16 is similar in dimensions to JF17(with JF17 being slightly smaller). F16's CFTs both combined carry 3000 lbs of fuel...so that's 1500 lbs each.

Now circling back to the JF17's underwing tank of 800 Kg(1764 lbs)...that 1500 lbs isn't too far off.

As for the drag induced by the extra munitions carried instead of the fuel tanks...well in absence of those munitions...when the fuel tanks are carried underwing...they also add to that drag...
...to remove those fuel tanks from underwing and attach munitions like an ARM missile...it wouldn't really add too much of an excessive drag penalty.

The biggest two drawbacks are...
1) not being able to use the 1100 Kg fuel tanks...the centerline can only carry 800 Kg...probably bcuz of ground clearance issue. So if the underwing hardpoints are not utilized for fuel tanks...that 1100 Kg fuel tank can't be carried.
2) the second main drawback is the added overall weight. Still hanging munitions...while also carrying extra fuel in CFTs...as opposed to only hanging fuel tanks and not using CFTs.

A minor drawback is still the slight difference in fuel...1764 lbs(underwing if using 800 Kg tank) vs the 1500 lbs estimate of the CFT...
...a difference of 264 lbs times 2 = 528 lbs.

Another minor drawback could be the drag induced by the CFTs...but that remains to be seen. It would depend on the aerodynamic characteristics of the CFT...it doesn't always have to impose a drag penalty...in case of the CFTs on F18 it creates lift IIRC.

In any case...CFTs on JF17B make sense in the wild weasel role bcuz of the two hardpoints that are freed up...other than that role it seems to be doing fine without CFTs.
 
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FB_IMG_1592772364294.jpg
 
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Thunder centerline tank is 800 litres not 800 kg. and the underwing 1100 litres not 1100 kg.
We know what the F16 CFT capacity is, so in abscence of an actual CFT for thunder, I assumed the same ratio to make my point.


no idea was just responding to some post regarding the increase in range with CFT's compared with underwing tanks

Is there a plan for jft cft
What?
Use of F16s underwing and centerline fuel carrying capacity here is not relevant.

Wouldn't the only thing relevant be the capacity of fuel tanks currently being carried by JF17 vs the fuel carrying capacity of potential CFTs on JF17?

It is the difference between the two that we are interested in. Currently(according to wikipedia)...the JF17 optionally carries an 800 Kg(1764 lbs) fuel tank on the centerline hardpoint...
...while the two underwing fuel tanks can be either the 800 Kg(1764 lbs) or 1100 Kg(2425 lbs).

So if instead of the two underwing hardpoints carrying fuel tanks...the two CFTs are to carry it...then we will need to know the capacity of the supposed conformal fuel tanks of JF17...which don't yet exist...hence why I had used F16 as an example here. The reason for using F16...as opposed to some other aircraft is that F16 is similar in dimensions to JF17(with JF17 being slightly smaller). F16's CFTs both combined carry 3000 lbs of fuel...so that's 1500 lbs each.

Now circling back to the JF17's underwing tank of 800 Kg(1764 lbs)...that 1500 lbs isn't too far off.

As for the drag induced by the extra munitions carried instead of the fuel tanks...well in absence of those munitions...when the fuel tanks are carried underwing...they also add to that drag...
...to remove those fuel tanks from underwing and attach munitions like an ARM missile...it wouldn't really add too much of an excessive drag penalty.

The biggest two drawbacks are...
1) not being able to use the 1100 Kg fuel tanks...the centerline can only carry 800 Kg...probably bcuz of ground clearance issue. So if the underwing hardpoints are not utilized for fuel tanks...that 1100 Kg fuel tank can't be carried.
2) the second main drawback is the added overall weight. Still hanging munitions...while also carrying extra fuel in CFTs...as opposed to only hanging fuel tanks and not using CFTs.

A minor drawback is still the slight difference in fuel...1764 lbs(underwing if using 800 Kg tank) vs the 1500 lbs estimate of the CFT...
...a difference of 264 lbs times 2 = 528 lbs.

Another minor drawback could be the drag induced by the CFTs...but that remains to be seen. It would depend on the aerodynamic characteristics of the CFT...it doesn't always have to impose a drag penalty...in case of the CFTs on F18 it creates lift IIRC.

In any case...CFTs on JF17B make sense in the wild weasel role bcuz of the two hardpoints that are freed up...other than that role it seems to be doing fine without CFTs.

simple in structure may be as they are nothing but tanks to hold fuel, but they are linked with the fuel pumping systems that are complex for multiple reasons including which tank to consume first at what rate as that impact centre of gravity and dynamics the other being able to supply fuel in all flight profiles. If it was as simple as you say, they they would have popped up many decades ago on every plane.



CFT is a very simple thing. First designed by Israeli conception. There is no magic to it. We have half-witted people here who don't know what they are talking about, making bland statements when they dont know jack about anything.

This is a sad mindset. Instead of trying to learn and grow, these fellows can neither learn nor help others gain anything other than their garbage. This garbage then creates more garbage minds.
 
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Thunder centerline tank is 800 litres not 800 kg. and the underwing 1100 litres not 1100 kg.
We know what the F16 CFT capacity is, so in abscence of an actual CFT for thunder, I assumed the same ratio to make my point.


no idea was just responding to some post regarding the increase in range with CFT's compared with underwing tanks
I took that info off of wikipedia...
I don't have a JF17 on hand and so internet searches are the next best thing...
https://en.m.wikipedia.org/wiki/CAC/PAC_JF-17_Thunder

There u can see the fuel tanks listed as 800 Kg or 1100 Kg...either can be used(on the underwing hardpoints).
...whereas the centerline fuel tank can only be 800 Kg.

Maybe it's a mistake on Wikipedia? For water it is roughly equivalent whether one uses Kg(unit of mass) or Litres(unit of volume)...bcuz the density roughly works out to be 1 Kg/L. So it could be that somebody swapped out the unit by mistake?

In any case using the density of jet fuel...the volume of the fuel can be calculated from the 800 Kg and the 1100 Kg number...
...unless these numbers are wrong to begin with.
 
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no one keeps a jet fighter handy in their back yard to get the true specs, do use the internet but an authentic site.

https://www.pac.org.pk/Jf-17

2.jpg




I took that info off of wikipedia...
I don't have a JF17 on hand and so internet searches are the next best thing...
https://en.m.wikipedia.org/wiki/CAC/PAC_JF-17_Thunder

There u can see the underwing fuel tanks listed as 800 Kg or 1100 Kg...either can be used.
...whereas the centerline fuel tank can only be 800 Kg.

Maybe it's a mistake on Wikipedia? For water it is roughly equivalent whether one uses Kg(unit of mass) or Litres(unit of volume)...bcuz the density roughly works out to be 1 Kg/L. Using the density of jet fuel...the volume of the fuel can be calculated from the 800 Kg and the 1100 Kg number...
...unless these numbers are wrong to begin with.
 
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no one keeps a jet fighter handy in their back yard to get the true specs, do use the internet but an authentic site.

https://www.pac.org.pk/Jf-17

View attachment 643615
That's even better if the current fuel tanks are of 800 L and 1100 L of capacity.

Let's just use the same unit for comparison...now that there's no need of using Kg and lbs...

Also using official sources this time...
http://www.defense-aerospace.com/ar...16-conformal-fuel-tanks-tested-(nov.-28).html

The source for that article above is Lockheed Martin.
It lists the F16 CFT's fuel capacity as 450 gallons(for both CFT combined). 450 gallons(unit of volume) = 1703.435 Litres

So one CFT can hold about 850 L
...if we assume JF17's CFT to be similarly sized as that of an F16's CFT(bcuz the two jets are close in dimensions)...then it seems that the CFTs can at least match 800 L fuel capacity of the underwing fuel tank.
 
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Block 52
Internal 3,975 liters
Centerline 1,135 liters
2x Underwing 4,542 liters
2x CFT's 1,665 liters

The fact is that the CFT's capacity is about 1/3 of the underwing tanks, hence the notion that by replacing underwing tanks with CFT's and hanging armaments on the underwing pylon would increase the range is factually incorrect.


That's even better if the current fuel tanks are of 800 L and 1100 L of capacity.

Let's just use the same unit for comparison...now that there's no need of using Kg and lbs...

Also using official sources this time...
http://www.defense-aerospace.com/ar...16-conformal-fuel-tanks-tested-(nov.-28).html

The source for that article above is Lockheed Martin.
It lists the F16 CFT's fuel capacity as 450 gallons(for both CFT combined). 450 gallons(unit of volume) = 1703.435 Litres

So one CFT can hold about 850 L
...if we assume JF17's CFT to be similarly sized as that of an F16's CFT(bcuz the two jets are close in dimensions)...then it seems that the CFTs can at least match 800 L fuel capacity of the underwing fuel tank.
 
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Block 52
Internal 3,975 liters
Centerline 1,135 liters
2x Underwing 4,542 liters
2x CFT's 1,665 liters

The fact is that the CFT's capacity is about 1/3 of the underwing tanks, hence the notion that by replacing underwing tanks with CFT's and hanging armaments on the underwing pylon would increase the range is factually incorrect.
I never said that by adding the CFT...it would increase the range.

The whole point I'm making is that with two CFTs and a centerline fuel tank...JF17 can carry about as much fuel as it would with a centerline 800 L and two underwing 800 L fuel tanks. It would add an overall more weight(weight of fuel, CFT, and the munitions hanging off the freed hardpoints) and possibly a bit of drag in addition to the fact that CFTs can't be jettisoned...and thus reduce the range a bit. So under normal circumstances it's just better to stick the fuel tanks under the hardpoints. However in certain cases like for SEAD/DEAD types of missions...it would be useful to have CFTs so that the hardpoints can be used for munitions. For example something like below...
2 ELINT pods on wingtips
2 WVR missiles
2 ARM missiles

As for using F16s underwing fuel carrying capacity...like I said before...that's not useful here. We are concerned with the fact whether or not CFTs can provide enough fuel to roughly match the 800 L or 1100 L capacity currently carried underwing. Using the dimensions of a jet(F16) that is close in size to JF17 and has CFTs...we can see that it is possible to match the 800 L capacity(each).
 
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While I agree with your post, I don't think CFT is as simple as you are making it out. From the top of my head I can think of a few factors that would have to be considered for its design.

1. Aerodynamics of the CFT itself
2. Reduced aerodynamics/lift factor of the wings
3. Added load on the wing structure
4. Dynamic loading due to the fuel inside sloshing around

See the post I was responding to that was making CFT out to be a capability China would have a hard time implementing. There is no such thing. That was a childish post and had to be straightened out. Al the things that you mention are not outside the capability matrix of PAC let alone China. If you read forward, CFTs according to messiach were long figured out in the JFT. Why are we still having this conversation...
 
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Its a laser guided bomb, our version of Paveway.
So they named it after the sword of Prophet Muhammad PBUH

The al-Battar sword was taken by the prophet Muhammad as booty from the Banu Qaynaqa. It is called the "sword of the prophets" and is inscribed in Arabic with the names of David, Solomon, Moses, Aaron, Joshua, Zechariah, John, Jesus, and Muhammad. It also has a drawing of King David when cut off the head of Goliath to whom this sword had belonged originally. The sword also features an inscription which has been identified as Nabataean writing.

The blade of the sword is 101 cm in length. It is preserved in the Topkapi Museum, Istanbul. Some report that it is this sword that Jesus will use when he returns to Earth to defeat the anti-Christ Dajjal.



Sent from my HTC One X9 dual sim using Defence.pk mobile app
 
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