UA can easily support a DEL flight provided they don't get over ambitious and try to route a double-daily 744 through there, which will trigger the capacity restrictions. If they stuck to a daily 777/763 flight through LHR, they could easily turn a profit on the route. India-US is a cash cow for everyone who operates it. AI (10x 744), DL (7x 763) and NW (7x 744) have same-aircraft direct service that is invariably full, while BA and SQ also control huge chunks of connecting traffic.