JF-17/FC-1 Fighter Aircraft thread

[ougoah]

Yep weapons integration is a long and difficult process. I never said it wasn't. PL-15 and PL-10 integration may take many years but work may have begun a long time ago. Who knows when block 3's planning for these missiles in mind would have begun. Block 3 coming out a year ago or so may have missed out on AESA. It is quite likely that block 3 will be tasked with meeting IAF's increased capability with its introduction of 36 Rafales to be completed in coming years.

Then again the delay could entirely be caused by the weapons integration where PAF/ China previously did not plan on equipping JF-17 with PL-15.

 

[Brumby]

The concept of BLK-III is to bring this baby as near as possible to J10Cs/J16s to face MKIs or Rafales in terms of sensors/avionics/radars, hence weapons integration (PL10/15) are not going to be an issue as the systems are already tested on J10Cs/J16s.

There is no doubt that with Block 3, the capabilities of the JF-17 will be enhanced. However you are conflating between effects and function. For example, an AESA equipped Block 3 will increase the detection range of the platform - that is the effect. How you achieve that effect is the functional capability of the eventually adopted AESA design for the Block 3. There will be trade offs in the design. That radar design will be different to that of the J-10 or the J-16. The point is that whatever integration work on the J-10/J-16 with the PL-15 has no relevance to the process that needs to take place with the JF-17. It will require the initial carry flight test for vibration and draq, the electrical interfaces between the store management system, the sensors, avionics, GPS, cockpit management system et al; priming and aiming testing; weapons load configuration testing; flight envelope release testing, carriage life testing and then finally a first firing test.

You need a Block 3 with stable systems to do all of the above. Currently such a platform does not exist. .

Who knows when block 3's planning for these missiles in mind would have begun. Block 3 coming out a year ago or so may have missed out on AESA. It is quite likely that block 3 will be tasked with meeting IAF's increased capability with its introduction of 36 Rafales to be completed in coming years.

Then again the delay could entirely be caused by the weapons integration where PAF/ China previously did not plan on equipping JF-17 with PL-15.

I do not understand your point about "planning" and how it is helping directly to front run the integration timeline. Integration is a progressive set of activities leading to eventual test firing and while that might involve program planning the primary drivers on how quickly integration can take place is the availability of test platform and the stability of its sub systems and that include the radar.

 

[Mohsin77]

I'm skeptical that the Block III's AESA will have the range to support the PL-15. There is no miniature AESA, as far as I know, which can make use of the PL-15's capabilities. If the Block III ever gets qualified for the PL-15, it will need to be cued via datalink from an AWACS, which is possible... but that will take a long time to get working.

As for the flight test delay, the fact that there's not even any leaked pictures of the prototype makes me thing that maybe the airframe is still being modified... There's just so many unknown variables right now and no official word... It's super annoying.

 

[ougoah]

I do not understand your point about "planning" and how it is helping directly to front run the integration timeline. Integration is a progressive set of activities leading to eventual test firing and while that might involve program planning the primary drivers on how quickly integration can take place is the availability of test platform and the stability of its sub systems and that include the radar.

I think my explanation was confusing. What I meant was that PL-15 integration could have been part of the plan for block 3. PL-15 is not the only upgrade to enhance the newer model's abilities. Integration may or may not be the thing delaying the fighter, assuming there is a delay at all. We are, and I certainly was assuming that blk 3 was planned to go into service before 2020. Even with that alternative timeline, it does not remove the possibility of PL-15 integration since the missile may have been planned for the fighter since the conception of blk 3 and work on integrating it could have been happening for years already. The delay could be caused by the fact they haven't been given enough time to properly integrate the new radar and PL-15 to the new block. So far it seems HMD and AESA are going to be fielded. PL-15 and PL-10 have not been confirmed.

I'm skeptical that the Block III's AESA will have the range to support the PL-15. There is no miniature AESA, as far as I know, which can make use of the PL-15's capabilities. If the Block III ever gets qualified for the PL-15, it will need to be cued via datalink from an AWACS, which is possible... but that will take a long time to get working.

As for the flight test delay, the fact that there's not even any leaked pictures of the prototype makes me thing that maybe the airframe is still being modified... There's just so many unknown variables right now and no official word... It's super annoying.

The PL-15's range is well under 200km. I'm sure for large RCS targets like Su-30MKI and the rest of IAF with the exception of the Rafale, the new AESA can comfortably detect and paint these targets at max range. Not that PAF will be wasting medium-long range AAMs at max range to deny entry. They can use older missiles for that. With estimated PL-15 max range at around 150-170km depending on launch altitude, speed, and target position, the no escape range is probably just above half that number. Well within even current radar's range.

 

[Mohsin77]

The PL-15's range is well under 200km. I'm sure for large RCS targets like Su-30MKI and the rest of IAF with the exception of the Rafale, the new AESA can comfortably detect and paint these targets at max range. Not that PAF will be wasting medium-long range AAMs at max range to deny entry. They can use older missiles for that. With estimated PL-15 max range at around 150-170km depending on launch altitude, speed, and target position, the no escape range is probably just above half that number. Well within even current radar's range.

I hope that it gets integrated. But I still think its utilization will require launch via datalink, not the smaller integral AESA of the Block III.

In order to fully utilize a 170km ranged missile, you need a radar that has at least a 250km range. Because if you start to detect the target at 180km, by the time you lock and launch, the range will be less than 100km, and the target will launch on you before breaking. We're talking about closure speeds of over a 1000 kms in most scenarios, and a lot has to happen before you can launch (clear ROEs, IFF, get clearances etc.)

With that said, I still want the PL-15 on the Block III if it can be integrated with the AWACS and the JF-17 is merely a missile carrier that launches and breaks before it even detects the target (or better yet, has its own radar switched off.) That's a very powerful combination.

In any case, as far as the flight test goes... I hope some intel gets released from somewhere... this suspense is killing me.

 

[ougoah]

I hope that it gets integrated. But I still think its utilization will require launch via datalink, not the smaller integral AESA of the Block III.

In order to fully utilize a 170km ranged missile, you need a radar that has at least a 250km range. Because if you start to detect the target at 180km, by the time you lock and launch, the range will be less than 100km, and the target will launch on you before breaking. We're talking about closure speeds of over a 1000 kms in most scenarios, and a lot has to happen before you can launch (clear ROEs, IFF, get clearances etc.)

With that said, I still want the PL-15 on the Block III if it can be integrated with the AWACS and the JF-17 is merely a missile carrier that launches and breaks before it even detects the target (or better yet, has its own radar switched off.) That's a very powerful combination.

In any case, as far as the flight test goes... I hope some intel gets released from somewhere... this suspense is killing me.

Do we have any specs on blk 3's radar range? I'm not sure if the unit has officially been disclosed but an AESA should be able to provide at least 180km detection range. Suppose it is 180km, you will want to launch the PL-15 within NEZ which is not anywhere close to 170km. R-77 and earlier AMRAAMs had about 80km of max range so PL-15's NEZ is already about the max range of previous generations of medium range AA missiles. So even if the AESA unit provides 180km detection, it will be more than enough to launch the PL-15 because it should be launched at about 80 or 90km. Closing speeds are usually not going to be at max speeds so let's say relative closing speed at launch is mach 3, that's roughly 1km/second. The lock and launch action itself should take a few seconds, accounting for decision making and positioning, maybe a minute or so. So detection to launch after deliberating for a bit more than a minute will result in distance closing from 180km to 110km or so. I just don't see the problem since the target is still outside NEZ and can turn around and then climb pretty quickly.

Then again I'm confident with support, there will be even less time used to reposition. Radars will be on since AESA have LPI.

 

[Mohsin77]

you will want to launch the PL-15 within NEZ.

Not necessarily. It depends on the tactical requirement. You might need to FOX much earlier. For example, if the target is about to launch at a friendly and you have to force him to disengage. That's what I mean when I say utilization of the full potential of the PL-15, that would only be possible with AWACS+Datalink integration. I hope they get it done, but it would take time... especially for the Swedish AWACS we are operating.

Do we have any specs on blk 3's radar range?.

I doubt the real number will be released even when its fitted. The F-35 radar's max detection is still classified, there are wild speculations depending on RCS, everywhere from 150km to 400km. No one knows for sure. But we do know that the Block III's AESA will be a small one, a 'mini AESA' basically. So it's a safe assumption that it won't be able to fully utilize the PL-15's potential by itself, without being cued by AWACS.

 

[ougoah]

Not necessarily. It depends on the tactical requirement. You might need to FOX much earlier. For example, if the target is about to launch at a friendly and you have to force him to disengage. That's what I mean when I say utilization of the full potential of the PL-15, that would only be possible with AWACS+Datalink integration. I hope they get it done, but it would take time... especially for the Swedish AWACS we are operating.



I doubt the real number will be released even when its fitted. The F-35 radar's max detection is still classified, there are wild speculations depending on RCS, everywhere from 150km to 400km. No one knows for sure. But we do know that the Block III's AESA will be a small one, a 'mini AESA' basically. So it's a safe assumption that it won't be able to fully utilize the PL-15's potential by itself, without being cued by AWACS.

I don't really buy into the whole launching missiles just to keep enemies at bay tactic. Certainly has a place but it's a good way for the opposition to exhaust your entire arsenal very quickly. Okay maybe PAF will be very selective with where and when they do this and weigh things up accordingly.

At useful ranges of PL-15, I think the new radar should prove more than capable enough. SD-10 which is export PL-12 is currently used on JF-17 with pulse dopplers. The PL-12's range is about 80km + depending on version. If the current radar can do justice to the SD-10, an AESA that is used to replace the current radar surely must be able to extend the "fireability" range of the PL-15. The Rafale uses a small AESA unit and more than allows for the full range of the Meteor which reaches further than the PL-15. Sure there are many finer details involved and the RBE AESA may be vastly superior in many ways but my point is size, T/R numbers, and power are not everything. If the RBE can make use of 200km missiles while being only marginally larger with perhaps higher T/R count and peak power, then blk 3's AESA compact nature alone, shouldn't stop it from giving justice to PL-15. We'll need to know what the detection ranges are like and what sort of resolution it can provide to really say. Guess we'll never know.

 

[Brumby]

In discussing radar detection range across different platforms, there are a few underlying factors that need to be understood in order to derive any meaningful understanding of the numbers.

Those factors include :
(1)The signal to noise (S/R) threshold that is used;
(2)The need to relate to comparative RCS;
(3)The radar mode used in establishing the number
(4)The probability of detection (P/D) that is adopted; and
(5)The difference between detection and tracking range.

(1) is never made available in the public domain and so the assumption is that they are similar across different platforms. This assumption is seriously flawed and consequently any comparison across platforms has this built-in underlying flaw.
(2)Any detection range quoted must relate to a RCS number. Without the RCS reference, the detection range is meaningless. Russian numbers tend to reference to fighter size target which can mean between 3 to 5 m2. US numbers tend to use 1 m2. Once the number and RCS is known, varying RCS can be determined using radar range equation. For example, a detection range of 100 kms against a 1 m2 target is equivalent to 150 kms against a 5 m2 target and 178 kms against a 10 m2 target.
(3)The search mode affects the detection range because of dwell time. The infamous 400 kms detection range claimed by the SU-35 IRBIS radar was based on a narrow search mode which effectively doubles the range.
(4)The PD % affects the detection range. The IRBIS radar claim to fame with its detection range was in using a 50 % PD. Western radars use 80 % PD.
(5)A firing solution is based on tracking range and not detection range. A rule of thumb conversion is to use 80 % of the detection range to get to tracking range. This only works for Western radar because as in (4) the PD adopted is 80 %. A valid track by definition requires a minimum three successive data points. The Russian in using 50 % PD will not get a reliable track from that range because 0.5X0.5X0.5 = 12.5 % PD As the saying goes, "you can cheat some of the people all of the time, all of the people some of the time but not all of the people all of the time". Cheaters do not win.

So in determining the JF-17 radar range, the question is more difficult to address because hardly any of the above is known and any number will be rather rubbery. In any case I have taken a stab. All ranges are expressed in kms.



.

 

[Brumby]

That's what I mean when I say utilization of the full potential of the PL-15, that would only be possible with AWACS+Datalink integration. I hope they get it done, but it would take time... especially for the Swedish AWACS we are operating.

I have on a few occasions seen comments in passing in this forum concerning the leveraging of targeting data off AWACs through data links.

I have serious reservations on whether this is even technically feasible for a number of reasons.

The first reason is purely distance. AWACs are high value targets and for this reason are typically kept within safe zone and this could easily mean 300 kms away from the air assets being supported. Any penetrating counter air engagements could at least 200 - 300 kms from the outer rim. This collectively puts a distance of 500 - 600 kms distance between the AWCs and any OCA. The Erieye currently has a detection distance using S band of 350 kms against a fighter size target. Such a set up means the Eireye would not have insufficient coverage to be of any credible use.



The second consideration is the nature of the data link. Any credible data links need to have high throughput with low latency. Data links such as Link 16 or "Link 16" like would not be technically feasible primarily due to high latency against fast moving maneuvering targets. Even in the case of the USAF, the use of third party targeting data using data links are restricted to IFDL and MADL links that are used by the F-22s and F-35s respectively. The USN has plans to roll out TTNT for such purpose but won't be in place until F-18 E/F Block 3s are introduced starting in 2020.

Finally, I question whether the S band range resolution is sufficient for targeting beyond its primary function of providing vectoring data.