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

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Never knew the forum was that touchy when certain fighters are written in a single line. I wrote that because the site in question was comparing the 2 and hence....
OK, lemme re-phrase that. *sigh*



Forgetting powerful radar's and BVR missiles for a second...
I once read in a certain* site that Tejas would fair poorly in a close combat scenario because its delta wings will bleed more energy(drag or slow down) with each turn, while jets having a conventional wing will not bleed as much energy like Tejas would. Is this assertion true?

Or in other words, what is its instantaneous turn rate and sustained turn rate?

Its Angel of Attack?

If that is not known, then atleast that of Mirage-2000 should be available to give a general idea where Tejas stands.

Also what is the ratio of thrust to weight for both the planes?


It is often said that, a BVR kill highlights the avionics, while a close combat gun or missile kill highlights the raw performance parameters of plane. So I hope if someone can clarify if the assertions are true or not.

I would not mind if people can share the above mentioned 4 parameters for Su-30MKI, MiG-29, Su-27, F-15, F-16, F-18, F-22, Eurofighter, Rafale, FC-1 & J-10 as well.
 
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...
 
Delta wings does have poor STR because of high drag of those wings as it requires more engine power to compnsate which both LCA and mirage-2000 doesn't have, but its ITR is quite high due to low wing loading. Mirage-2000 has higher ITR than the F-16, and same as that of the MiG-29. MiG-29's ITR is 28 degrees per second while F-16's is 26 degrees.
Luftwaffe MiG-29 experience - positives and negatives


STR for JF-17 F-16, MiG-29-
Watch JF-17 vs F-16 vs MiG-29 Turn Rate Comparison Video | Break.com
From the above video,
JF-17 - 22.5 seconds for 360 degrees. So STR is 360/22.5 = 16 degrees per second
F-16 - 18 seconds for 360 degrees. So STR is 360/18 = 20 degrees per second
MiG-29 - 16 seconds for 360 degrees. So STR is 360/16 = 22.5 degrees per second


By the above its obvious now that the STR of the Mirage-2000 is less than that of the MiG-29. Further confirmed by this - Beauty vs the Beast You can extend the mirage data to Tejas as well. But are Tejas and Mirage-2000's STR less or higher than JF-17? Most probably will be lower or the same as that of JF-17, due to their delta wing but a bit higher TWR. At the same time, most probably the very same low-wing-loading delta-wing of the Tejas and Mirage-2000 ensures their ITR will be higher than the JF-17. MiG-29 is unique and leads in both STR and ITR because, its high thrust to weight ratio compensates very well for its drag/air-speed-loss caused by its low-wing-loading-high-AoA-STR-turn, while the very same low-wing-loading & its unique fuselage-body lift ensures a good ITR.

Su-30MKI has a lower STR due to less TWR than the MiG-29, but its ITR is very huge due to thrust vectoring and canards.


AoA of Tejas is currently 22, which will be increased to 24 in FOC.
Livefist: IAF Grudgingly Accepts Tejas IOC, Wants 83 Mk-IIs

For thrust to weight ratio of the fighters, go here - Thrust to Weight Ratios of all Fighters



Sorry about the spelling errors, keyboard not working properly.
 
Just re-read again and there were quite a lot of silly errors which unfortunately changed the entire meaning of sentences. I was quite busy yesterday and just raced through the reply without proper proof-reading. I bet many of you were scratching your heads reading some of the sentences I wrote yesterday, because it didn't make sense. Sorry about that. I've corrected it.


To sum up what I've wrote yesterday..

ITR
1# Su-30MKI
2# Mirage-2000 & MiG-29 (28 Degrees per second)
3# F-16 (26 Degrees per second)
? JF-17
? Tejas

AoA
1# Su-30MKI
? MiG-29
? F-16
? Mirage-2000
? JF-17
? Tejas (22 / 24 Degrees)

STR
1: MiG-29 (22.5 Degrees per second)

? Su-30MKI
? F-16 (20 Degrees per second)

?? JF-17 (16 Degrees per second)
?? Mirage-2000
?? Tejas


TWR
1: MiG-29
2: Su-30MKI
3: F-16
4: Mirage-2000
5: Tejas
6: JF-17

G Loading/Tolerance
1: Su-30MKI, MiG-29, F-16, Mirage-2000 (9Gs)
2: Tejas & JF-17 (8Gs)

Corner Velocity
1: MiG-29
? Su-30MKI
? F-16
3: Mirage-2000
4: JF-17
5: Tejas


The Units for these terms are
ITR - Degrees per second (Higher is better)
STR- Degrees per second (Higher is better)
TWR - No unit. Its just a number. (Higher is better)
AoA - Degrees (Higher is better)
Gs - No unit. Its just a number. (Higher is better)
Corner Velocity - Km/hr or Knots (Lower is better)
 
LCA is the lighter aircraft of its class with better specs . It would be the best interceptor and CAS aircraft after FOC .
 
Both are similar in performance , because LCA was mock up of saab viggen and Mirage . Still LCA is no where near the capabilities of Mirage .
 
Both are similar in performance , because LCA was mock up of saab viggen and Mirage . Still LCA is no where near the capabilities of Mirage .
Mock up of viggen? whatever! So pilli, what is the offbore sight angle of Pili? Any idea?



I think none of the missiles in the subcontinent has 90 degree offboresight. Only ASRAAM, RVV-MD and Aim-9X has 90 degrees. So the bulk of the turning has to be done by the aircraft using maximum thrust vectoring ITR. R-73 has only 60 degrees and Aim-9M, what is the off-bore sight of the Aim-9M anyway? 45 degrees or 60 degrees?

One thing is for sure, Aim-9X looks completely different from its predecessors.
sidewinder_family.jpg
 
Both are similar in performance , because LCA was mock up of saab viggen and Mirage . Still LCA is no where near the capabilities of Mirage .
Ya like J10 is a mock up of IAI Lavi or Saab Gripen or is it a cheap copy of Eurofighter....and J17 was desiegned by Romania...as it is copy of Romanian Desiegn IAR 95.......
 
Well IOC-1 trails proved LCA Tojes AoA, G limit and speed is way below IAF requirements so you can't compare a unfinished jet with Mirage 2000.
 
Ya like J10 is a mock up of IAI Lavi or Saab Gripen or is it a cheap copy of Eurofighter....and J17 was desiegned by Romania...as it is copy of Romanian Desiegn IAR 95.......
what ever we mass produce our aircrafts with out any ones dependence where as you still beg components from other countries .

while you ended up as failure in mocking mirage :haha:
 
LCA Tejas' and Mirage-2000's close combat performance are almost the same as LCA is a copy of Mirage..I think LCA wouldn't outperform Mirage as it was tend to replace Mig21's.
 
LCA Tejas' and Mirage-2000's close combat performance are almost the same as LCA is a copy of Mirage..I think LCA wouldn't outperform Mirage as it was tend to replace Mig21's.

unlike our neighbor we don't have weapons/jets xerox machines..... If we copied M2k, french will never offer Rafael to us....
 
LCA Tejas' and Mirage-2000's close combat performance are almost the same as LCA is a copy of Mirage..I think LCA wouldn't outperform Mirage as it was tend to replace Mig21's.
really???Do you know any thing about Engineering???
 
^^^^ You just proved it ...........There is no similarity ..........

what ever we mass produce our aircrafts with out any ones dependence where as you still beg components from other countries .

while you ended up as failure in mocking mirage :haha:

Says a guy from a country which uses russian engines on copied russian aircrafts ........:wave:
 

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