JF-17 Thunder Multirole Fighter [Thread 4]

[Viper0011.]

While talking to one of my friends (who maintains close links with AF), he told me that according to his cousins ,the JFT of Hussain shaheed disintegrated in mid air. He also told me that the aircraft was being tested at Mach 2.2. I remember we did have quite a lot of discussion on the topic but still every now and then something exceptional turns out. He told me a lot of other things as well which I would share, if required.

This is simply not true. Every heard of wind tunnel testing? When that happens, an airframe (even a dummy or a smaller version) is tested at different airspeed; way above and beyond its required capabilities. The purpose is to ensure, for example, in case of trying to break a missile lock, the plane may go pull extreme g's to break the lock and of course with full speed. With that, certain angles and turns will impact the plane from the gravity's standpoint as if it was flying much over its speed limit.
So the airframes are tested thoroughly for a higher speed. The idea isn't to run the plane on that higher speed at all times. The idea is to check and see how strong is the structural integrity of the plane under such circumstances.

If JFT was being tested for Mach 2.2.....unless it was doing it 24*7 for weeks, I don't buy that by doing a ten minute Mach 2.2 test, its structural integrity got compromised.

Next, usually the reason behind a plane's disintegration in the air is pure structural. Primarily older airframes, weaker spine, over loaded weapons causing significant stress over a longer period of time to the airframe, etc. Weak spine causes most of it. If the speed was an issue, it would've resulted in an engine failure first, resulting in giving pilot some time to eject or putting the plane in a Jet Wash where the plane just falls out of the sky turning so hard in every way that the pilot is trying to stay conscious vs. passing out, and that makes it difficult to eject. Plus the wind, turns and stress in this case MAY cause the plane's wings to detach. The spine should still be in tact however. But this isn't due to the speed. It's due to the engine failure.

 

[SQ8]

JFT vs F-16A from the Izmir Air Show, F-16 was still 10 times better than JFT in this case. It's turning makes me feel like am watching the aerobatics of an F-7 fighter.

It's right here in front of you, now elaborate how did you come to ten times better?
Turn rate? Corner airspeed calculations? T/W? What?

 

[Argus Panoptes]

It's right here in front of you, now elaborate how did you come to ten times better?
Turn rate? Corner airspeed calculations? T/W? What?

The JF-17 display is from 5:09 to about 7:20, followed by the F-16 till the end.

The turn rates are pretty similar for sure. The F-16 clearly has a better T:W ratio than the JF-17, witness the climb out at 9:50 or so.

 

[Thunder_Rider]

It's right here in front of you, now elaborate how did you come to ten times better?
Turn rate? Corner airspeed calculations? T/W? What?

Look Carefully...... the climb of JFT vs F-16A, the Turning rate, the of maneuverability of JFT is no where near the maneuverability of F-16A. And about that "10 Times",
by "10 times" I meant to explain my point, not to undermine the A/C. Thanks

 

[SQ8]

Look Carefully...... the climb of JFT vs F-16A, the Turning rate, the of maneuverability of JFT is no where near the maneuverability of F-16A. And about that "10 Times",
by "10 times" I meant to explain my point, not to undermine the A/C. Thanks

how did you come up with measuring the turn rate?
Do you know the corner airspeed for both A/C? Are they the same?
The T/W issue of thunder is well known, but the turning rate claim I find ludicrous based on ... what?

 

[Thunder_Rider]

how did you come up with measuring the turn rate?
Do you know the corner airspeed for both A/C? Are they the same?
The T/W issue of thunder is well known, but the turning rate claim I find ludicrous based on ... what?

Ok...... Let me make it clear,
I'm pointing out the difference or similarities on my personal inception. Conner Speed ? I don't know, Do you ? If you do then point it out brother, make my doubt clear. If you are trying to point out that JFT's main issue is about T/W Ratio then, why is Gripen more impressive in Turning, Maneuvers and etc then JFT ? It also have a T/W Ratio of under '1' (of 0.97). Why does JFT not seems similar with 0.96 ?
I admit that Turning rate is pretty similar to F-16A but why JFT still falls behind an A/C which was produced in 1980s ?
What I believe ? I believe it's bcoz of the Engine on which JFT is powered on......

See this: JAS 39 Gripen aerobatic display 2006 at Dalajärna airshow 2006 - YouTube

 

[Dazzler]

10-115 at CAC, notice the underbelly "pod"

UPDATE on 06..

"Fierce Dragon" 06 static test aircraft proceeded smoothly

*
Recently, 06 the AVIC Chengfei "Fierce Dragon" static test aircraft completed over 1100 channels of internal patch work into a comprehensive the fuselage wing adhesive tape paste. Early all the preparatory work is progressing smoothly, and has laid a good foundation for the follow-up test to carry out. Xu of Bo Xing-root photo coverage

 

[Bratva]

10-115 at CAC, notice the underbelly "pod"

UPDATE on 06..

"Fierce Dragon" 06 static test aircraft proceeded smoothly

*
Recently, 06 the AVIC Chengfei "Fierce Dragon" static test aircraft completed over 1100 channels of internal patch work into a comprehensive the fuselage wing adhesive tape paste. Early all the preparatory work is progressing smoothly, and has laid a good foundation for the follow-up test to carry out. Xu of Bo Xing-root photo coverage

I wish another hard point added under chin which could act as a pod dedicated station. Pod Underbelly is wasting crucial hardpoint there which i think can carry the much heavier loads as compare to other 6 points

 

[S-A-B-E-R->]

10-115 at CAC, notice the underbelly "pod"

UPDATE on 06..

"Fierce Dragon" 06 static test aircraft proceeded smoothly

*
Recently, 06 the AVIC Chengfei "Fierce Dragon" static test aircraft completed over 1100 channels of internal patch work into a comprehensive the fuselage wing adhesive tape paste. Early all the preparatory work is progressing smoothly, and has laid a good foundation for the follow-up test to carry out. Xu of Bo Xing-root photo coverage

so what is that pod .irst or a flir or some kind of ecm pod?

 

[SQ8]

Ok...... Let me make it clear,
I'm pointing out the difference or similarities on my personal inception. Conner Speed ? I don't know, Do you ? If you do then point it out brother, make my doubt clear. If you are trying to point out that JFT's main issue is about T/W Ratio then, why is Gripen more impressive in Turning, Maneuvers and etc then JFT ? It also have a T/W Ratio of under '1' (of 0.97). Why does JFT not seems similar with 0.96 ?

Because your perception of turning rate is incorrect. You seem to be basing it on how fast the aircraft is going and not how tight it's turning. The JFT has a lower corner airspeed than both of these types.
Now, there is also a difference in instantaneous and sustained rates.
Take a look at this video, without the clipping of the JF-17 performance.

The JFT starts it's max turn around 0:46-47.. by 0:51-0:52 it's already pointing the other way..his wings are almost 90 degrees(lift is coming from sideslip)... around 0:56 we can see that he is losing airspeed(this is where the t/w ratio kicks in) but he still maintains his turn rate by increasing his AoA ever so slightly.(The aircraft rolls to the left a little).. By 1:06(and I assume the camera stayed where it was.. the JFT is done with a 360 degree turn in 19-20 seconds. You do the math on that.

In comparison, Here is a F-16 doing a 9G turn at its corner airspeed(BTW, the 9G is only sustained in instantaneous.. most of the turn its around 7-7.5G)... 19-20 seconds?

You think that's impressive.. here the F-16 does the very same 360 turn in a whopping 16-17 seconds.

Now, that begs the question? are the two F-16's different? or does it have to do with how the turns were made.
The F-16 in the first video still had enough energy to continue a maneuver(or a fight). The one in the second video bled all his energy out in that turn which is why he levels out to gain some airspeed for the next trick.

The question then in a FIGHT.. not an airshow.. is that of sustained and instantaneous turn rates.

Unless you know the exact figures for the JF-17 and F-16, you cannot say who turned better and who did not.
I know a gentleman whose currently Dir Ops JF-17 and has flown both types so I do have some rough idea.. but Ill only say this on the matter.

In the DACT's that took place during the initial T&E period around 2007-2009...Whenever the F-16 won.. it won due to being able to outclimb the JF-17.

I wish there is another hard point added under chin which could act as a pod dedicated station. Pod Underbelly is wasting crucial hardpoint which i think can carry the large heavy loads in compare to other 6 points

Probably has to do with the pod-size and load-bearing capability of the intakes(which are still largely sheet metal and not that strong.. a honeycomb structure would have been better..but more expensive)

 

[Armstrong]

In the DACT's that took place during the initial T&E period around 2007-2009...Whenever the F-16 won.. it won due to being able to outclimb the JF-17.

For a Layman like myself :

(i) What significance does that have ?

(ii) Is that because of F-16's better T/W ratio ?

(iii) Is that a weakness & its ensuing threat, we're looking into to cover ?

 

[Argus Panoptes]

..........

In the DACT's that took place during the initial T&E period around 2007-2009...Whenever the F-16 won.. it won due to being able to outclimb the JF-17...............

The superior T:W ratio also comes in handy in all maneuvers, not just climbing ones. Recall that the rate of change of velocity is acceleration, and thrust throughout a accelerative maneuver can improve its sustainability.

 

[Dazzler]

For a Layman like myself :

(i) What significance does that have ?

(ii) Is that because of F-16's better T/W ratio ?

(iii) Is that a weakness & its ensuing threat, we're looking into to cover ?

is simple words, F-16 excels in vertical realm due to very powerful engine but jf-17 has better horizontal agility due to bleeding edge LERX, DSI, quick engine response time and a more responsive quad+ dual redundant FCS (blk -15s have single analog fly by wire FCS), both will try to take another to their backyard

so what is that pod .irst or a flir or some kind of ecm pod?

if i remember correctly, it appears to be similar to the pod that we saw when JFT was used as a chase plane for J-20, it could be some optical pod or something new, could be a specifically designed pod since it has the same rear body as KG-300G jammer? cant say for sure

 

[Argus Panoptes]

is simple words, F-16 excels in vertical realm due to very powerful engine but jf-17 has better horizontal agility due to bleeding edge LERX, DSI, quick engine response time and a more responsive quad+ dual redundant FCS (blk -15s have single analog fly by wire FCS), both will try to take another to their backyard

The superior T:W ratio is useful for all maneuvers, not just vertical. The JF-17 will scrub off speed much quicker than an F-16 in any axis due to less thrust available to maintain the maneuver.

Redundancy of the FCS aids safety, not agility. Agility comes from other design factors, including control surface areas and their locations.

 

[Safriz]

is simple words, F-16 excels in vertical realm due to very powerful engine but jf-17 has better horizontal agility due to bleeding edge LERX, DSI, quick engine response time and a more responsive quad+ dual redundant FCS (blk -15s have single analog fly by wire FCS), both will try to take another to their backyard



if i remember correctly, it appears to be similar to the pod that we saw when JFT was used as a chase plane for J-20, it could be some optical pod or something new, could be a specifically designed pod since it has the same rear body as KG-300G jammer? cant say for sure

as you pointed out....looks more like a chase pod....