Hi,

I don't think I've ever had my bags tagged through when entering India, even when connecting to the same airline on the same ticket. I've always have to collect my bags and clear customs at the first port of arrival.

Its a fairly easy transfer from Arrivals to departures once he's cleared customs and it is clearly signposted. He will need to show boarding pass(es)/ print out of booking and passport to the guard on the lift. As far as I can remember this transfer needs to be done following the route inside the terminal. If he goes outside and tries to go back in through the main entrance he may get stopped by the guards for being 'too early' for his next flight.

AI does have both baggage drop off counters and normal check in counters in the terminal. I'd advise joining whichever queue looks shortest- everyone else does.

If the transfer time is long there is a good chance they wont take his bags. If its over 4 hours I think they can get a bit funny about it. I have managed to get them to take mine about 7 hours early in the past but it took a bit of arguing and I think they only did it because I was flying in Business, have status and was connecting on the same PNR.

In conclusion this is doable but might be a bit of a pain. One option (depending on budget) would be to book into the terminal hotel. They will then send a greeter to guide you through immigration/customs and sort things out for you. Worth it if the layover is 8+ hours I'd say but not otherwise.

If you let me know the flight times I can advise further. Generally when I have transfers like that I forget hanging around the terminal and check into a nearby hotel for the night.