That's because of upgrades.
Check what is known officially about the Bars radar. Double it, that's IAF's Bars capability on new MKIs. Stuff like this goes unreported.
The duty cycle of the Kopyo-M is above 25%, the same as what's on LCA. So, it is not inefficient. It has a smaller radar array, and hence requires greater power to match LCA's range. That's because the gain is smaller on the Kopyo-M.
It was the Bison which made USAF say that inferior platforms fitted with BVR will be a major threat to superior American platforms. This applies to LCA too. Overall the Mig-21 is an inferior aircraft. But it has far higher speed as compared to LCA so it does not have to stay in the fight after firing its missile. It has the option of running, the same as what it did after killing F-15s in CI-2004. Come within 10Km of the fighter, fire BVR missiles and run. Add a superior breed of pilots already flying the Mig-21 compared to LCA, the man always beats the machine.
Only BVrs fired from bisons hit the F-15 not the experience of bison pilots .Speeds won't matter much,because once the ge-414 engined mk-2 comes it will have much better top speed than mig-21.
Even the mk-1's 90 kn engine can be upgraded with HIGHER TWR k-10 in future ,so they too will have much better top speeds post upgrades after 10 years.So every single LCA tejas inducted into IAF is worth it's place.No debate about it. First IAF ordered 20 mk-1, and then it increased the order to a total of 40 mk-1s,voluntarily.
The machines capacity enables man to beat the enemy, experience won't make up for inferior radar detection and tracking range.Any rookie pilot on LCA will use this excess radar detection and tracking range. And LCAA is the most modern fly by wire aircraft in IAF , so flying it won't be as risky as MIG-21 s it is a universal truth.FBW will ensure carefree operation even for rookie pilots, opposed to mig-21 which is an unforgiving aircraft to fly.
Superio breed of mig-21 pilots will do a much superior job in tejas, So people dont need to worry on that count.
Having a 10 or 15 Km range advantage does nothing. If you remember what I posted before, an aircraft only carries weapons that it itself is capable of using. Mig-21 carries the 70Km R-77, LCA will carry the 50Km Derby. So, Mig-21 has the BVR advantage too. 20 whole seconds of advantage. Once the 70Km Astra Mk1 is fitted on the LCA, it will be time for Mig-21s retirement.
This is the main problem with your argument. You don't understand modern fighters are weapon platforms.The present tejas can fire a 120 km meteor if it is mated with it.No new hardware addition is needed.Let me say how,
1. Once tejas detects an aircraft at 120 km it does not have to worry about tracking range either. AS modern BVRs have active seekers which will finish the enemy once they reach within 18 kms . This is your statement.So tejas can fire at will. The mig-21 with 80 km detection range cannot do that.
If people argue against it as I expect, The first thing I am going to ask from them is,
WHAT IS GRIPPEN GOING TO DO WITH METEOR AS IT TOO HAS SIMILAR PYLON LOADS, RADAR RANGES AND SAME AS TEJAS IN ALL ASPECT. If they are not ready to clarify this point then they must do the decent thing and keep SHUT UP
2. It's tracking range is also given as 120 kms officially. Then it can give mid course guidance as well,
3.Even if it has a 80 km tracking range , if it flies another 30 km straighter it will start guiding the missile accurately.In this job it is as good as any other fighter.
4.SO it is unfair to compare mig-21s to LCA.For people saying that lca can carry only 2 long range bvrs , they can go to rafale thread here and see" MULTIPLE BVR LAUNCHER RACKS " on rafale and clear their doubts. I won't elaborate on this matter.
5.If they are not convinced after that they can go to GRIPPEN sites and see how many BVRs it carries.
Anyway, read this.
Mig-21
Scroll to the bottom and you will notice the specs for the Kopyo (a radar version inferior to the one Bison was first upgraded with) was far superior to the EL/M 2032(Mig-21 Lancer). And the 2032 did not even come with BVR capability, with lesser targets tracked and only a one target capability.
Upgrades happen in a cycle. You don't deliver 5KW of power now and say your range is 75Km. So, what is consistent with EL/M 2032 today, will be the same for Kopyo-M. Even Bars has undergone 4 upgrades over the last 10 years with the biggest one being in 2008-09. Specs double every few years. The 130Km range on Bars-1 (Pune squadrons) was upgraded to 200Km on Bars-2 and will now see a 400Km range upgrade with the AESA version of Bars(or Phazatron). While Bison wouldn't have seen such major upgrades, it is enough to state there would have been enough upgrades to fire the R-77 effectively. It's been a decade after all.
Same for Rafale's RBE-2 which will see a 200Km range, up from 100Km range today.