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LCA Tejas' and Mirage-2000's close combat performance

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what ?
Saab_JA37_37447_Swedish_Air_Force_Marcel_van_Leeuwen.jpg

Saab_VIGGEN_AJ-37.png

Tejas_3_view.gif

HAL_Tejas_AeroIndia-2009.JPG


canards are absent which makes aircraft to perform still worse than viggen

really!!!!!! viggen was intended for ground attack while LCA has completly different task.
 
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what ?
Saab_JA37_37447_Swedish_Air_Force_Marcel_van_Leeuwen.jpg

Saab_VIGGEN_AJ-37.png

Tejas_3_view.gif

HAL_Tejas_AeroIndia-2009.JPG


canards are absent which makes aircraft to perform still worse than viggen

If you know the engineering, LCA wings ended near pilot seat , which provide lot of wing area and lift , while Viggin wing ended at half of plane body which the lower part can get lift and upper part remain absent . there they need canards.

if you increase the Length of LCA and wing ended before 50% of body then you need canard to have same performance
 
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what ever we mass produce our aircrafts with out any ones dependence where as you still beg components from other countries .
Like you keep begging Russia for your jet engines! Chinese dependence on Russian engines can only be explained by technological inferiority of Chinese engine-building.

For many years China has been the biggest buyer of Russian military planes. Overall it has bought 178 fighter jets of only Su-27/Su-30 family – until producing a copycat of it, named J-11.

They also replicated Russian deck-based fighter Su-33 (J-15), Su-27 fighter jet (J-10), Su-30 (J-11), MiG-29 (FC-1). The J-20s will most likely fly with Russian engines for years before they make a reliable engine of their own.

So there! And stop spewing garbage when you know squat!
 
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Nice questions. But I bet many ppl don't even know what those terms mean. So i'll go over them first.

Angle of Attack(AoA) is the maximum angle an aircraft makes against the air flow. Practically it means, the greater the angle of attack, the more vigoursly you can turn. If the Angel of attack is breached, then the aircraft ceases being an aircraft and becomes a giant metal in the sky hurtling towards the earth. This is what is called as stall. Normally you can breach AoA for 2-3 seconds. Anything more than that then the aircraft loses lift and becomes a falling brick. This problem is solved by the use of thrust vectoring. Using thrust vectoring, the dangerus stall phenmenon is fully eliminated now. Now you can go into even the most dangerus types of stall with 100% chance of recovery. Also with Thrust vectoring, the AoA limit can be breached without adverse effects. This is important in close combat because the more the angel of attack, the more tighter the pilot can turn. So aircrafts having high AoA wiill have smaller turn radius.


Thrust to Weight ratio(TWR) as the name implies is obtained by dividing the Engine-thrust of a fighter by its weight. If the Thurst is more than its weight then the result of that is a number greater than 1. If thrust is less than the weight, then the result is a number less than 1. So for fighters with numbers more than 1, these fighters can zoom up into the sky like a rocket instead of gradually increasing their altitude. Also having more thrust to weight ratio means, the fighter can use the maximum use of its angle of attack. It wont matter if your fighter has a high AoA but a poor thrust to weight, because your fighter at maximum high AoA creates more drag and slows down the fighter. The more you turn with the help of high AoA, the more you loose speed. The only way to counteract this losing of speed, is for the engine to put out more power. More engine power(or in other words more thrust to weight ratio) means, more thrust to counteract the drag due to high AoA turn. Say both Fighter-A & Fighter-B have an angle of attack of 25 degrees, but A has TWR of 1.2 while B has a TWR of 1.1. Since A has more engine power than B, it will turn more tightly than B because the more engine thrust will counteract the slow down due to a high AoA turn. So eventhough both B and A has 25 degrees of AoA, B won't be able to fully utilise its 25 degrees, and will be turning at 22 degrees AoA only, because if it goes to 23 degrees it will create extra drag which cannot be counteracted by its engine thrust and will start to lose speed and become a sitting duck soon. While Fighter-A will turn at 24 degrees AoA because at that angle the drag will be counteracted by its superior TWR(or more engine thrust).


Sustained Turn Rate(STR) and Instantaneous Turn Rate(ITR) are very imprtant parameters.
STR as the name implies is a turn which can be sustained. STR is a derived quantity from AoA and TWR. As explained above, the balance between AoA and TWR makes Fighter B to turn at 22 degrees AoA only because if it goes abve that, it will start to lose speed. At 22 degrees AoA and TWR of 1.1, lets assume Fighter B can complete a full circle 360 degree turn in 20 seconds, without losing air speed. So its sustained turn rate is, 360 degrees divided by 20 sec, which is 18 degrees per second. So the STR of Fighter B is 18 degrees per second. While Fighter A with 24 degrees AoA and TWR of 1.2, will complete a full 360 turn much faster than Fighter B. Lets assume it completes it in just 16 seconds. So its STR is 360/16 = 22.5 degrees per second.

What this means is, if both fighter A and Fighter B meet each other head-on in a fight and start turning(it is called a merge), (the initial difference in angle in a head on engagement is 180 degrees.), Fighter A due to its superior STR(it has a superior STR because of a superior AoA, and it got its superior AoA because of its superior TWR. Now you can see how these parameters interact with each other.), will slowly start to get behind Fighter-B. Fighter-A has an advantage of 4.5 degres per second(22.5-18), over B. So to cover 180 degrees(or get behind B's back), Fighter-A will take 40 seconds to do it(180/4.5). So after A and B meet face to face, Fighter A will be behind Fighter B in just 40 seconds and pump his asss full of lead with his cannon or missile. This is what STR is all about.

ITR , is a turn which is performed instantaneously. Here the full 25 degrees AoA is used by both fighters A and B. As a result, both A and B whose STR limits them to 24 and 22 degrees respectively, doesn't matter here. Ofcourse turning at 25 degrees AoA creates massive drag, which slows down both the fighters, with B slowing down much more than A. So you can ask, why on earth would a fighter turn like that, lose speed and become a sitting duck? A few years ago that would have been true, but with the new short range high off boresight missiles, all u have to do now is to turn using your full AoA advantage and quickly point your nose to the direction of the enemy fighter, get a lock on, with your missile, and then fire! It is this ITR which the Russians and the Americans have increased greatly with the help of Thrust vectoring. With thrust vectoring, as mentioned before, you can safely even exceed the 25 degrees AoA without losing control of the aircraft. So you can turn instantly, move your nose in the general direction of the enemy, get a lock on your HMS, get a good tone on your Short range off-bore sight missile, and launch it.
With off bore-sight missiles, this becomes even more easier since you don't have to fully turn and only come into the off bore of the missile in order to launch. So when on a headon engagement(180 degrees difference), Fighter-A with 90 degrees high off boresight missiles and HMS, coupled with thrust vectoring, will perform a much higher ITR, and as a result will turn faster and will be able to get a lock-on much faster than, Fighter-B with its own 90 degrees high off boresight missile and HMS, but without thrust vectoring. 90 Degrees Thrust vectoring + 90 Degrees with HMS-offboresight missile = 180 degrees covered from the initial head-on angle.

Ofcourse performing ITR will kill your airspeed, and hence if your missile misses, then you are dead. That's why most fighters now carry more missiles to increase the chance of a hit. For example, the Su-30MKI can carry 6 or more R-73s each.


Another 2 parameters which are important are the G tolerance and corner velocity. But explaining everything written above in the context of Corner Velocity and G load, will complicate it further. I think this is more than enough to give a basic understanding of close combat.



Now with that finished, lets move on to real fighters...

Main reason why F-15 and Flanker series are agile fighters despite their large size
 
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I appriciate your gratitude and support for your master :kiss3:

:woot:Are u high or something... < Insult bardasht nai hui ya insult ki vja sy oopar ka portion kharaab ho gya hy>
 
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Are we talking about the LCA on paper spec or the real one? On paper, it beats Mirage 2000. In reality, it falls way short of Mirage 2000.
 
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the question is why do we need to compare the close combat performance Of LCA to a Mirage 2000 as of now both Mirage and LCA are with India or is that some people are thinking of procuring Mirage Against LCA = i guess quatar is not such a desperate country to Give its Mirages to a Cash Strapped Air Force ;) .... or is it:azn:
 
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I think Mirage-2000 is an awesome machine. Even some of the experts told that IAF should have gone for about 80-90 Mirage-2000 from France old ones in order to counter their own MiG-21s which are no good and Mirage-2000 can take over their duties well.
 
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