My personal observations,
When LCA started out, IAF and ADA did indeed work together. However while IAF wanted a workable fighter like JF-17 to replace the MiG-21, ADA wanted to incorporate bleeding edge technology.
Things came to a breaking point when IAF wanted to use proven Dassault analogue FBW software while ADA wanted to develop its own quad channel digital FBW. Both IAF and ADA PoV hold merit. IAF PoV was using a proven subsystem will quicken development. ADA PoV was new system technologically superior.
At this point IAF walked out because its PoV was not being considered by ADA.
In hindsight, the ADA FBW system had a long development time, Lockheed Martin was roped in to assist testing the software, 1998 Pokharan happened, they kept the code, neither Boeing nor EADS could assist testing, and even today, the Tejas flight envelope has not been fully opened up. Hence implementing IAF's PoV would have resulted in a quicker and less risky development
The radar and engine were even murkier stories. No one kept track of how development was progressing. There was no internal audit done or review conducted.
Once IAF walked out, user feedback became unavailable. Small issues – like stressing the outer wing to carry a better missile – became big issue. ADA said original spec said R-60. However, if ADA was projecting themselves as seasoned designers, they should have kept in mind that R-60 was rapidly becoming obsolete, and they should have future proofed the outer wing by sufficiently stressing it. IAF acquired R-73 only in 1996-97 with the Su-30.
Not one BR member in LCA thread could respond why air intakes, that is one of the first things being designed and tested via computer modeling, simulations and wind tunnel testing, still has issues 10 years after first flight? Couldn’t we test, discover these issues and resolve then in the last 10 years?
Many members cited stealthy Y ducts, however, the primary function of a duct is to supply air and the secondary function is to offer stealth. Isn’t it irrational fulfilling secondary function while failing the primary function? A stealthy intake duct is designed for a plane that chokes it and restricts its envelope?
Refer here,
http://www.cadfamily.com/download/CAE/n ... CA_ada.pdf. This is a 2003 study. The first three points on the first slide make the problem amply clear. So problem is known, simulation tools are available, yet problem persists to this day.
Practically, the stealthy duct is meaningless. Firstly, in a single engine aircraft, the forward fuselage hides the compressor face, unlike a twin engine plane like F-14 or Su-30. The simplest approach would have been focusing on supplying air to the turbofan ignoring the stealth requirement.
There are operational issues with inducting a platform like LCA.
An aircraft with sound basics and less than optimal performance OVERALL can be inducted. Not an aircraft exceeding performance in some areas and lacking in others. So, a chap with 15 inch biceps and normal lungs can be inducted. Here we have a chap with 18 inch biceps and asthmatic lungs. The 18 inch biceps doesn’t compensate for the asthmatic lungs.
Now, when ADA ignored IAF’s Point of View regarding flight control, how can one expect IAF to keep partnering? It takes two to tango. When one partner organization’s PoV is repeatedly disregarded, the natural reaction of that partner organization is WTF, go to hell.
DRDO’s feverish desire to over engineer to create superlative systems has been its major reason for failure and acrimony with its end users.
BR members say services don’t take initiative, however there is a history behind the mindset of the services.
Having said that, things are changing for the better in both organizations.
Its always 80 : 20 principle. 20% is best performing than the rest 80. Same in Army or IAF or Navy.