WoW
24h? I am counting...
15 years?
India import parts from all over the world, so the planes of IAF can have much less than 15-year-gap with China, some of them could be quite similar, e.g. Su-30 MKI and J-11b.
However, producing planes reflects the underlying large scale industrial sophistication of a country. If measured from this angle, India-assembled plane (the 1st and the only one and still unfinished: LCA Tejas) , which is the hallmark of Indian industrial capabilities (i.e. assembling imported foreign key parts under guidance of foreign consultants, & final painting of course) by and large, is about 50 years behind China's industrial might and sophistication (today's India can not even match China's industrial depth & width and engineering indepedence of 1960s after the Soviet-split), and the gap is enlarging by the day...
Anyway, it's not my intention to be off-topic. Let's come back to J-20's incoming new version.