AI/IA come out with ads for trainee first-officers once every two years or so , they also occasionaly look for senior first officers with usually an ALTP and jet time ....I don't really remember when the last ad was.....
Requirements for trainee first officers are usually:
2.COP RTR--basically Indian R/T.
3.Unrestricted medical, Indian of course.
4.FRTO issued by DGCA.
5.250 hrs TT & maybe 25 hrs multi.
Everything should be current and will be examined at the time of the written exam and they are quite pedantic about it , you can't tell them here's a copy, the original's submitted in DGCA.
Ads usually come out for maybe 20-40 candidates and 50% are reserved for SC/ST/OBC .....
As for who you know that counts , I think knowing someone working in Air India might help in terms of what sort of preparation's required for the written/oral exams , also getting all your paperwork current and running is in itself a difficult task.Experience does help, I've been told by senior pilots who interview but corruption cannot be totally ruled out too.....good news is things are getting better slowly but surely.