Many members are taking genuine questions like criticisms and as if a difference in fighter development can be seen from projects in Europe, US or even India.
Testing an manned fighter is an exhaustive ball game. Let's say you have 1000 parameters to check. You have successfully tested 999. And then have an issue with an last one. You redo the change even if by adding one if statement. You have to retest all 1000 parameters again. And the funny part is, that one statement will break any other parameter and will again relook at the code. Testing and validation is fun
And this validation can't be done with one ac. You need to have variables. One needs to have preferably atleast 3 protos almost with the same design. And if the first proto has some minor design issue, it needs to be rectified in the second. Or the existing one needs to be modified and again tested for 1000 parameters.
And again it would be kinda fun integrating all electronics to the mission computer. And when sub-systems fail testing, the engineers have to pray to God hoping it's not an hardware issue. If it's software it can be modified with sometime. If it's hardware it has to go back to design review of that sub-systems, testing and validation again.
And then testing an new aircraft would ask for new test infra in the country or have to ask LM or BAE facilities to do testing (it can fastrack schedules). Test jigs, fixtures have to be designed and installed for testing mechanical parts for limited production as well.
I think the BAE role here is to certify and qualify the aircraft. Certification and qualifications is a separate huge discipline altogether. No one will certify any aircraft in 1-2 year. Cos it needs data, flying variables under different conditions, min hours required.
India learnt from Tejas, the hard way. I think LM was supposed to be our advisor, but the nuclear tests of 1998 put an full stop to it. India had to develop everything from scratch. From FCS tool, test infra (huge), modalities, certification and we had our pilots trained in US on how to become test pilots for new aircrafts etc. The only thing we were worse were in management and decided to use our own engine instead of going foreign. It wasted nearly 8 years of our programme. These are the only advantages Turks would have but the other dev activities can't be shortened, cut or dealt with. It has to follow normal development process which is trial and error.