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JF-17 Radar Dome Size

I have used this foto for the EF-2000 : http://data3.primeportal.net/hangar...ails/eurofighter_typhoon_t_lfsr_01_of_17t.jpg and used the 5.28m height from wiki: The radome is about 980 cm and assuming 80%, the antena is about 780cm.

For the J-10B i have used this image : http://img521.imageshack.us/i/20680009.jpg/ and also the height from wiki = 4.78m which is for the J-10A so if the J-10b has a different height to the j-10a then that will be another source of error. The slant face of the radome is about 850cm on the major axis which assuming 80% = 680cm.
 
(Izvinite sto pisem na engleskom, ali hocu da me razume bez da mu translator nesto pobrka.)

I have to disagree, for the sake of facts. There's four reasons, please read everything before replying, and try not to get me wrong :D Also, I know that you probably know most of this already, but I still have to write it down when elaborating :)

a) The radome and subsequently the antenna size of the JF-17 is being grossly overestimated on defence.pk. I understand where it comes from, but I will still point it out to you guys, for your own benefit (if you are really interested in the technical specifications of the airplane and not just do it for the good feeling of knowing yours is better than others) I've read claims of around 1 meter, which is, realistically, far from the truth (more on that later). They are based on pixel counting with unreliable numbers and unusable angles, which are only good for guesswork in the +/- several decimeter range, and often feature obvious errors in measurement which are overlooked, but even if they didn't, then:

b) The diameter of the radome at the point of attachment, or even of the antenna itself, doesn't necessarily give you any reliable information about the range of the radar unless you have a lot of other factors to factor in together, and even then there is no reliable calculations to be made, and until then it is pure guesswork and wishing.

c)The radar antenna is not necessarily located in the backmost position of the painted radome part. Here's a few pictures for illustration purposes:
http://1.bp.blogspot.com/-ZAO-14Eq0...gDU0zk/s1600/f16_block60_nose_radome_open.jpg

Mig-29SMT


Rafale:
the f16pic shown here is of blk60
contin..........................................
 
And finally, the JF-17 itself. Here's the point of attachement of the radome cover, the one which some on defence.pk "measure" (guess) as 1 meter and directly translate that into antenna diameter:


Here's what the mounted radar looks like:


This is it from the outside, compare it to the wheel or human head, doesn't look as huge now anymore, does it?:


Notice something? Before starting to argue back about the size or whatever with some paint-lines and pixel counting, just go back to point b). :)

d) The most important part. Here's the brochure for the Selex Grifo radars. It contains the antenna diameters for the planes that the radars are intended for, including JF-17 and F-16. I am sure you've seen it before, but why you wouldn't believe it is beyond me. Let's assume that all the diameters are the maximum, full antenna diameter available in each planes radome, and why wouldn't they be? They are made to fit, after all. Here's the PDF, if you want to check any of my further elaborations.
http://www.selex-sas.com/EN/Common/files/SELEX_Galileo/Products/GRIFO_FAMILY.pdf

The antenna diameter of the radar intended for the older Mirage fighters is 51cm's. AFAIK Pakistan has them and is replacing them with the JF-17. So far so good.

The antenna diameter of the radar intended for the JF-17 is 60cm's. It is larger than that of the old Mirage's, which is pretty much the way it should be when the plane is intented to replace them for the future, it should be better. And comparing it to the pictures above (starting from the last one from outside, then working up to the shots of the radar antenna and it's respective position inside the previously seen radome), it seems more than reasonable, it seems perfectly realistic to me. And I would be hard pressed to come up with a reason why it should be smaller than the antenna diameter of the KLJ-7, after all Selex Grifo radars are all about small space optimization, so there is no reason to not believe that they exploited the full and maximum available space.

Now, the radar antenna diameter given for the Grifo for the F-16 is the known 74cm x 48cm's. So that's correct.

If we now calculate the area of the 60cm radar antenna on the JF-17 and the 74x48 cm radar antenna on the F-16 we'll see that they are of pretty much the same size:
F-16= 2789cm^2
JF-17= 2827cm^2

A difference of 1,3%, which is nothing.

So I have to disagree on the point that it has a larger radar antenna. Also, refer to point b, that the radar antenna diameter alone doesn't determine the range of the radar. The F-16 Block52+'s radar is much more advanced by itself and delivers more range per watt and cm^2 than the KLJ-7 radar. Also, the (as you already pointed out yourself) engine power of the JF-17 is the limiting factor and not the antenna diameter, and since the F-16 has a more powerful engine (due to the larger size/diameter of the engine itself), it will also be able to power much more powerful radars than the JF-17 ever will, even when it gets a new radar or engine.
Don't get me wrong, I hope I don't step onto your pride or something like that, I just want to discuss the technical aspects.

Comparing the JF-17 with the F-16 is a mute point anyway, because one is simply a class above the other in engine power and MTOW, while the other one has other advantages, like price and therefore numbers, and operational costs, while proportionally (in proportion to the difference in engine and weight class) being good enough/just as good or even better (it's anyones own opinion). It would be much more correct to compare the J-10 to the F-16, due to the similar engine class and weight load, and the J-10 could in fact support a radar similar in characteristics to the F-16, while carrying (if they work on the construction) just as much load and having an engine in the same power range. Of course, there's the whole technology thing, and jamming and jamming resistance and other gizmos, but I'll stick to the measurable, simple stuff now.

So they are both excellent planes and good designs to improve upon. They offer a lot of bang for the buck, and are a great addition to Pakistan and many other Air Forces in the world, but one shouldn't overestimate their features. I mean I totally understand it, we guys are exited if our country builds a piston engined or turboprop plane, we would probably get together and celebrate the sht out of the weekend if our country would start producing an aircraft like the JF-17, even if with assistance from another country. The JF-17 is a perfect replacement for the Q-5 and older Mirage and Mig-21 fighters, while the J-10B will be a good replacement for the older F-16 versions. I am not trying to belittle them or anything, but I am just assessing their possibilities and characteristics realistically. :D They both will guarantee the future of the Pakistani Air Force for at the next 3-4 decades, until China comes up with a medium sized 5th gen aircraft, so you guys are very lucky there, that you have such a good partner that can provide you with very affordable and perfectly useful hardware tailored for your needs, and that you have no outside pressure on who you can buy from.

mareCar responded to a post which would essentially be directed towards tempest and nabil
JF-17(FC-1) Thunder
 
OFF TOPIC.
Sir, i'm new here.. I'm not expert.
But i've a question for you.
Is there any spectulation/negotiation for AESA to be assembled at PAC..?
As we'll get them in numbers for thunder upgrades in future (2015). :/
 
Thanks ANTIBODY, that is the article I was searching for: 600mm-800mm.

600mm is a good size and combined with other subsystems being optimised, can give good perfomance. The Gripen radar is 600mm.

Yes, we are very aware performance is not just about the antenna, but antenna size is one of the MANY factors.

Pixel counting has got it errors and we acknowledge that but concerning the KLJ-7 specifically, it is the best info we have.

@ mareCar, can you please present better info? So far, you have presented Grifo data and ASSUMED that to be the same for the KLJ-7.
 
gambit said---

''It is not the 'nose' but the fuselage that matter, particularly the wall that separate the 'nose' area from the rest of the body . It is the wall's dimensions. That is where the radar antenna is mounted. If this wall and radome volumn can accommodate a larger antenna, no problem installing the larger one.
''

http://www.defence.pk/forums/pakist...-ranges-different-fighters-3.html#post1900916

so , anybody got those specs?
 
diameter of the radar dome -rough estimate

F-20/T-50 => ~500mm (APG-67 family)
Gripen => ~500mm (PS/05 family)
M2000 => ~500mm (RDM, RDI, RDY families)
Rafale => ~600mm(RBE family)
MIG-29 => ~624 mm (N019, N010 families)
F-16 => ~660mm (APG-66, APG-68, APG-80 families)

JFT =>~ 670-740 mm

Typhoon => ~700mm (ECR-90/CAPTOR family)
F-18 => ~700mm (APG-65, APG-73, APG-79 families)
F-35 => ~700mm (APG-81)
F-22 => ~900mm (APG-77)
F-15 => ~950mm (APG-63, APG-70 families)
SU-27/30 => ~1000 mm (N001, N010 [924mm antenna ver], N011 faimilies)
MIG-31 => ~1400mm (N007 family)

As long as we are on the same topic, i would like to know the exact size of nose cone sizes (dia+area) of all major aircraft in use with Pakistan and India.

I know following.

1. JF17 (prototype 1)............600mm ... 282,745 mm2 (assuming circular)
2. JF17 production................660mm ... 342,119 mm2 (assuming circular)
3. Mirage 2000.....................674mm ... 356,787 mm2 (assuming circular)
4. F16...................................??????
5. Su30................................1000mm . 785,397 mm2 (assuming circular)
6. F15...................................1000mm . 785,397 mm2 (assuming same as Su30)

I have added Su30 info as i read it somewhere i dont remember, and it was also mentioned that it was in same category as F14/F15.

Correct me if i am wrong ... add info if you have some source ... but don't comment if you dont know **** and just want to increase your post count.

Also add info on GrippenNG, Rafale, Eurofighter and J10A/B if you have it.

Regards,
Sapper


I have been constantly digging around for more information on radar sizes, and found some new information.
I am updating the radar specs for a few more aircraft.

I can be wrong about some of these specs, so please contribute to make it as fool-proof as possible.

1. JF17 (prototype 1)--------600mm ... 282,745 mm2 (assuming circular Radome)
2. *JF17 production-----------664mm ... 346,278 mm2 (assuming circular Radome)
3. Mirage 2000--------------674mm ... 356,787 mm2 (assuming circular Radome)
4. *F16------------------------740x480 ... 278,973 mm2 (elliptical Radome, Unconfirmed)
5. Su30----------------------~1000mm . 785,397 mm2 (assuming circular Radome)
6. F15------------------------~1000mm . 785,397 mm2 (assuming similar to Su30)
7. *Rafale--------------------550mm ... 237,582 mm2 (circular Radar Antenna)
8. *Mig35--------------------700mm ... 384,845 mm2 (Zhuk-AE/FGA35 Antenna)
9. *F18-----------------------700mm ... 384,845 mm2 (Unconfirmed if Radome or antenna)
10. *Eurofighter--------------~750mm ... 441,786 mm2 (Unconfirmed speculation)
11. *LCA----------------------650mm ... 331,830 mm2 (Circular Antenna, Radome Unknown, but will be bigger)
12 *Grippen-------------------~600mm ... 282,745 mm2 (PS-05/A Antenna, Radome will be bigger)

Some updated figures may be wrong ... since i tried my best to find at-least 3 sources to site my claims ... found less than that for some info i have posted above. So forgive me for any mistakes.

Regards,
Sapper

Some more updates ...

1. JF17 (prototype 1)----------600mm ... 282,745 mm2 (assuming circular Radome)
2. JF17 production-------------664mm ... 346,278 mm2 (assuming circular Radome)
3. *JF17 GrifoS7---------------600mm ... 282,745 mm2 (GrifoS7 circular Antenna)
4. Mirage 2000-----------------674mm ... 356,787 mm2 (assuming circular Radome)
5. *Mirage 3 Pk------------------470mm ... 173,494 mm2 (GrifoM3 circular Antenna)
6. *Mirage 5 Pk-------------------510mm ... 204,281 mm2 (GrifoM5/S5 circular Antenna)
7. *Mirage F1---------------------510mm ... 204,281 mm2 (GrifoF1/S1 circular Antenna)
8. *F16---------------------------740x480 ... 278,973 mm2 (Grifo16 elliptical Antenna, Radome will be bigger)
9. Su30-------------------------~1000mm . 785,397 mm2 (assuming circular Radome)
10. F15---------------------------~1000mm . 785,397 mm2 (assuming similar to Su30)
11. Rafale------------------------550mm ... 237,582 mm2 (circular Radar Antenna)
12. Mig35------------------------700mm ... 384,845 mm2 (Zhuk-AE/FGA35 Antenna)
13. F18--------------------------700mm ... 384,845 mm2 (Unconfirmed if Radome or antenna)
14. Eurofighter-----------------~750mm ... 441,786 mm2 (Unconfirmed speculation)
15. LCA--------------------------650mm ... 331,830 mm2 (Circular Antenna, Radome Unknown, but will be bigger)
16. Grippen--------------------~600mm ... 282,745 mm2 (PS-05/A Antenna, Radome will be bigger)
13. *Grippen NG-----------------~700mm ... 384,845 mm2 (Speculated Vixen 1000 Antenna)


Regards,
Sapper



Some more comparisons
 
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