@ramu &
@knight11 have a question sir the reason we went for LCA(a light aircraft ) was our inexperience in developing an aircraft plus the engine , now we neither are inexperienced nor making an indegineous engine so y not try to go for an slightly bigger design of Tejas something in the league of F16 around 7.5 ton to 8.5 ton . Then Tejas would not be just a point defence fighter and will be able to undertake more duties as it will have more fuel and will also be able to do ground strike duties of Mirage much better .
@ramu
give it a read I think Tejas will fit in perfectly here for us.(if we ever face such a scenario.)
Japan Scrambling Jets at Cold War Levels | The Diplomat
Good question to explore the reason we have to go to the time when the HAL proposed the GOI for the development of the fighter plane for the replacement of Mig-21. But govt. created ADA, and asked the IAF to formulate and submit its ASQR i.e requirement. Now IAF took 9 years to submit its ASQR, after which the ADA was given the funds for the preminary design study to check whether the technology in India is able to develop LCA. After which the funds could be released for the development of the prototype.
Now its clear that ADA have to develop the fighter plane as per the requirement of the IAF, so the small light wt requirement of the IAF could be due to the following reason :
1. IAF was impressed with the GNAT, which was small but agile fighter plane with short take off capability. So in another word you can treat LCA as the direct decendant of the GNAT.
2. IAF have mig-21 in large numbers, so they want the fighter plane that could fit in the already existed hangers.
3. IAF primrary wanted the fighter plane to replace mig-21, which was given the role of the interceptor, so they don't want long range for deep strike but for the point defense fighter plane, whose role fighter was been replaced with it.
4. IAF intended to use in mountainous airfield, which could take off from small airfield.
The earlier target was 1995, which was the fighter plane which was gen-3, a GNAT-2 fighter plane. But IAF took 9 years to formulate ASQR, and govt took another 3 years to release the fund due to economic crisis. The time was wasted but ADA used this time to study and work on 4 core technology, because now new technology was started impressing IAF --
FBW, Composites, FADEEC & turbo fan, BVR capability.
From Mig -29 - radar, BVR, WVR missile (Earlier fighter planes were only guns, rockets only)
from mirrage 2000 - FBW, FADEC, BVR, RADARS, glass cockpit
Jaguar -- LGB, Aerial refuel
Later on -- EW Suites, Center fusion, Data link,
So, the requirement of IAF now increases, because of the emergence of new technology and the goal post was changed for the LCA for the 4 gen from 3rd gen.
Question arises why they gone for the Delta wing with no tail and not the conventional design
Answer lies in the requirement of taking off with full load, in high altitute like LEH. The FBW developed for the LCA is another reason why ? Because with this design, they have less control surface, and if they could have included the Canard like Grippen, the FBW, and the Control law would have been more complex, so they came up with unique design of the wing, thus eliminating the canard and simple air inlet design.
Question why they go for the composite and that too in such high percentage
So LCA have to use the composite to fulfill its ASQR requirement
Question arises why Kaveri fails :
Changes required more thrust and power, which cannot be increased now. So the new ASR requirement of the IAF killed kaveri, because to achieve that, the engine have to be developed from the zero again and with the budget of 1.2 billion allocated, it was not possible, because the M88 engine was developed with 2.5 billion by the dassault in 10 years with experience of decades of engine making. And for those making fun of the kaveri project, no where in any country, the engine (turbo fan) was developed from the scratch in less than 40 years. China is an example, and very well know the difficulty in this development, because they have pumped around 100 billion in various engine development and R&D.
Question arises why difficulty in IOC, FOC
The first flight of the Legendary F-14 ended up in the crash, such thing could send LCA into the gallow.
For FOC the reason is the small size of the LCA, now makes things complicated, because the avionics have to packed taking care of heat problems in small space. So, the problem of the space makes the choice of off shelf foreign product difficult.
As far as you question is concerned, there is one another question Should they have gone for bigger fighter plane.
The answer is ADA have done great, because the knowledge, and technology they have learned in the fighter plane making give us the capability, now that we can go for the bigger MMRCA in Tejas MK3 with G-414 EPE engine with 110 kn. And I think this was the last chance we have to become self reliance in this field, because the technology is evolving way too fast and to keep up with that, it would have been impossible to cope up with without pumping huge amount of money, because till the time you develop a fighter plane, several new better technology evolves and the old Giants like LM, boeing, MIG, Sukhoi, Chinese won't like it be happened in the country which is the biggest arms importer in the world. After all its all buisness.
Rest assure there is no technology which is more than 5 year old in Tejas and
The one who flies swear to it, and who never flies discuss it.