TWA's zenith occurred in the summer of 1988, when, for the only time, the airline would carry more than 50 percent of all trans-Atlantic passengers.
Britain is demanding large concessions because, it claims, American and United would be strong competitors for its own trans-Atlantic passengers.
These airports can be inconvenient, especially for trans-Atlantic passengers, who must arrange their own transport from an international airport for connections.
Several of the earlier ships carried trans-atlantic passengers and played a role in German immigration to the United States.
It began service on the New York to London route in 1958, the first year that more trans-Atlantic passengers traveled by air than by ship.
Virgin is also among the airlines developing telephone, fax and other communications capabilities for trans-Atlantic passengers.
At its peak, in 1980, the airline was carrying one of every five trans-Atlantic passengers on its DC-10 planes.
For trans-Atlantic passengers, in fact, more competition - that is, more flights - lies ahead.
Last year, of the 669,701 trans-Atlantic passengers to Ireland, 55 percent went only to Shannon.
Sir Richard also said that he expected to attract 10 to 12 percent of British Airways' first-class trans-Atlantic passengers.