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JF-17 Thunder Multirole Fighter [Thread 4]

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Gripen have canards, why not JF-17s?? That's advantages over JF-17s.

Gripen_Air_Display_440x293.jpg

This question belongs to the design phase of the aircraft. Gripen and JF-17, though both single engine, were designed by two different aero industries. The debate of canard vs. conventional layout is complex and never ending as there are certain scenarios which favor one or other. There is no ultimate loser in this debate as yet. Like, If canard provide extra lift they contribute to the RCS of the aircraft. But this is just one argument. List of arguments from both sides goes on as aero engineering is still evolving.
 
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Hi, I am assuming the weight has been cut down on this iteration of the SD-10(b or c?). The question is, is it light enough to be carried on the wingtip stations of the JF-17.

Also I am curious if the PAF has inducted the initial SD-10 version, or are waiting for the SD-10B? Can anyone please shed some light on this topic?
 
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Hi, I am assuming the weight has been cut down on this iteration of the SD-10(b or c?). The question is, is it light enough to be carried on the wingtip stations of the JF-17.

I dont think SD10 work with the wingtip, but works well with inner station
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Also I am curious if the PAF has inducted the initial SD-10 version, or are waiting for the SD-10B? Can anyone please shed some light on this topic?

PAF may have 2-3 dozens SD10, may not have more....as PAF more intrestred in any following SD10 versions

PL-12B: with improved guidance system
PL-12C: with foldable tailfins for internal carriage on 5th-generation fighters
PL-12D: with a belly inlet and ramjet engine for even longer range attacks, similar to the PL-21

20110627_38.jpg
 
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Hi, if the PAF can induct a ramjet powered SD-10 that would be amazing. I recall reading an article way back in the early 90s, in which it mentioned the USAF had secretly tested a ramjet powered AMRAAM in the first gulf war against the Iraqi AF.

A ramjet version would be very long ranged, and also cut down an opponent's reaction time.
 
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This question belongs to the design phase of the aircraft. Gripen and JF-17, though both single engine, were designed by two different aero industries. The debate of canard vs. conventional layout is complex and never ending as there are certain scenarios which favor one or other. There is no ultimate loser in this debate as yet. Like, If canard provide extra lift they contribute to the RCS of the aircraft. But this is just one argument. List of arguments from both sides goes on as aero engineering is still evolving.
The main advantage of canards is that these make aircraft manuverable at supersonic speed vis-a-vis conventional layout. The reason is the shockwave and pressure mounted on tail making it almost unreactive whereas canards being mounted on frontal end can still be used for manuvering at supersonic speeds. We also have to consider the layouts, the detalwing of grippen also means that it will though turn tighter but will bleed energy quickly due to immense drag. Conventional layout may not turn as tight as a deltawing, but preserves energy and momentum.
 
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The author is too flawed in his description for example

1-AFAIK, EW is not a passive technology but RWR is which author has mixed up with EW, the author also apparently describes AESA as PESA, because AESA does not apply passive tech but avoids detection by employing LPI tech.
2-The author also apparently does not know that passive sensors have their own limitations vis-a-vis active sensors.
3-It is indeed in Passive mode but if grippen relies only on passive while its opponent also uses active sensors to agument passive ones. Grippen would be a clear looser. For example, the passive sensor may tell you that you have an adversary in 200KM but does not tell you where to be exactly.

I think by “EW” he is saying “Electronic Warfare” and not “Early Warning”. Therefore he could be including the RWR and other sensors link SigInt.
With regards to passive sensors not being able to determine the distance/location of the adversary … … I thought there were attempts (likely someone has something working already) to put sensors on the tips of thee wings and tail fin thereby be able to triangulate the point of emission? … … The USA put out tenders for bistatic airborne early warning a few weeks ago. With Gripen and its famous datalink wouldn’t three Gripens be able to detect and locate an adversary passively?
 
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The main advantage of canards is that these make aircraft manuverable at supersonic speed vis-a-vis conventional layout. The reason is the shockwave and pressure mounted on tail making it almost unreactive whereas canards being mounted on frontal end can still be used for manuvering at supersonic speeds. We also have to consider the layouts, the detalwing of grippen also means that it will though turn tighter but will bleed energy quickly due to immense drag. Conventional layout may not turn as tight as a deltawing, but preserves energy and momentum.

Now this is again a VS. argument. You can see both have their own pros and cons; Now it is up to designer / customer what they need. Tight turn or less energy bleed.
 
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Gripen have canards, why not JF-17s?? That's advantages over JF-17s.

Gripen_Air_Display_440x293.jpg

No it isnt, its just design philosophy.
The canards are there to offset the delta wings inherent aerodynamic setbacks.
Canards offer advantages in terms of high AOA capability among other things.
A post from another forum might clear things up.

I think a lot of people are also confusing canard aircraft with canard deltas. A stable canard is better than a stable wing tail, and a stable canard delta is better than a delta, but delta wings have there own issues, more internal volume and less weight/unit area, but that is only due to the low aspect ratio. The high sweep angle loweres maximum lift and steepens the Cl Alpha curves. This means a lot of drag in a turn.

I think for low speed designs in general aviation that a canard has a lot of advantages. One being that when you stall such a plane the canard stalls first so you get the desired nose down pitching moment but the wing is still producing most of its lift so the sink rate is not as bad. Plus such designs are stable so there is the drag benefit.

For a combat aircraft there are advantages to all configurations. Canards can be used as brakes better than a tail. Weather you pitch a tailplane up or down it will try to lift one set of wheels off the ground while a down-pitched canard would just push down into the ground. to make an unstable canard to me seems to be foolish, really. It takes away all of the benefit of canards!! Are the figures for the F-35 based on planform shape and main wheels? if so... I had no idea its pitching moment arm was going to be so large, and it has large surfaces. I notice that there are no canarded "supermaneuvering" aircraft. Yes the Su-35/37 HAS canards, but it already had sufficiant supermaneuver pitch with its large tails and they added TVC as well. I guess then Tails allow for greater non aerodynamic maneuvering (pitch moment based, or post stall). Now I know its all still aerodynamics but I think of aerodynamic turning as a "sustained" Cl pulling the whole aircraft around, not a pitch moment exceeding the AOA limits.

and more on the subject countering the above post.

However in the typhoon since design is unstable in the sense that the aircraft wants to pitch all the time means in a turn the canards direction and intensity of force varies with time accordingly to the pilots demands and the dynamic situation of the aircraft. In adition to that the downforce necessay to keep the aircraft leveled is relatively reduced. The arm moment is large thus the force necessary is smaller, similarly like a lever.

A typhoon making a hard turn will have its cannards ease off the downforce, or even use lift.

Most tail elevators are located nearer to the centroid of lift wich in turn is behind the CG. That necessitates a larger downforce that subtarts that of the wings.


Comparing both concepts, the tail configuration aircraft will aquire higher angles of attack than a given aircraft with a similar wing loading.


Similarly to the typhoon, the F-16 albeit with tail elevators doesnt mean they are producing downforce all the time. During pitch for example in a take off, the elevators direction of force varies from down to up lift several times per second. That happens because the planes got the CG behind the lift centroid making it unstable but in a different way the typhoon is.

An f-16 or F-35 during a hard turn will have both downforce at the moment of initial pitch and up force once the aircraft reaches the desired AOA for the main wings to produce the necessary lift. when that hapens the elevators literaly hold the aircraft heavy weight. A very different efect than that of the typhoon.

did this made sense to you?

You can conpensate the disavantages of tail planes with a lower wing loading but that also requires more thrust due to extra drag. During the turn that extra drag is ofset by smaller AOA induced drag. But for the lobgest part of the mission the plane will spend more fuel.

Usualy canard unstable deltas have more vicious spin charestics that are harder to defeat by design. That is in my opinion why US has stayed away from it since they can conpensate that with a large wing and the most powerfull engines in the world.

canardvstailhc5.jpg
 
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Well I remember Alan warnes saying about JF-17 and EF-2000 DACT training .... He said we'll know after a week..and then the crash happened and we never got on it after that... can some one on twitter ask Mr Warnes what he was about to inform us ..PLZ..:flame:
 
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Some users over here are facing some problems in knowledge.
Let me add one more point. Pakistani Pilots/Airmen are working in China for Chengdu. No, not joint co-operation or joint-venture, but they wear Chinese uniform and live in China. They are hired by China. Best thing to say is, they are Pakistani National but work for PLAAF.

As for test flights, Sir Kaiser Tufail has test flied the J-10A.
And they very first flights of Pt-01 were made by Chinese guys. But P.A.F pilots flew every Prototype, (except for Pt-06) as it is given major technological changes and the Chinese are evaluating for their use. After the end of this Research, our pilots maybe given the Pt-06 to see if we would like to upgrade the Avionics.

SD-10 is the major objective. If we try to seek new avionics, the first thing will be the avionics used on Pt-06 and the major reason would be BVRAAM. No chance for WS-13 on the Thunders Block 1 though.
 
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jf3m.jpg


Those pitot tubes are huge. Don't you people think.
 
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I think by “EW” he is saying “Electronic Warfare” and not “Early Warning”. Therefore he could be including the RWR and other sensors link SigInt.
With regards to passive sensors not being able to determine the distance/location of the adversary … … I thought there were attempts (likely someone has something working already) to put sensors on the tips of thee wings and tail fin thereby be able to triangulate the point of emission? … … The USA put out tenders for bistatic airborne early warning a few weeks ago. With Gripen and its famous datalink wouldn’t three Gripens be able to detect and locate an adversary passively?
Actual i meant that he was duducing Electronic Warfare by EW. AFAIK, EW is not a passive process. if both aircraft are slient and your Passive sensors will get nothing, it will be just like two blind men walking in the street. IMHO active and passive sensors complement eachother. Even on Erieye, there are passive detectors on wigtips which in-turn helps AESA to look for most probable object areas. Its just like passive sensor initates the presence of an object, but active sensor pinpoints it. The advantage of passive sensors is their relatively very long range vis-a-vis active sensors but their disadvantage is the lack of preciseness.
 
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