It depends whether it is a nonstop flight or if it is a one stop through a European airport most likely London Heathrow. I doubt there would be a nonstop flight from Houston to Delhi, because the only plane Air India migh use for that distance would be the 777-200LR. Notice that Delhi is in Northern India near the Himalayas. A twin engined plane like the 777 cannot currently fly over the Himalayas due to international regulations. A non-stop flight from Houston or Dallas would be much more likely to go to Mumbai (formerly Bombay), because the restrictions on twin engined planes flying over the Himalayas would not apply. It is likley that instead of being nonstop, the flight would fly first to London Heathrow first, then go to Mumbai (BOM) or New Delhi (DEL). Due to the intermediate stop, they could fly a 747-400 which has no restrictions flying over the Himalayas. A stop at Heathrow would be very beneficial to DFW, because Air India has 5th freedom rights in and out of Britain to pick up and drop off passengers going both directions. Under the Bermuda II protocol currently Dallas is not on the list of cities from which US carriers can fly to Heathrow. Air India has the rights to land there, and they aren't bound by Bermuda II.
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