 This was also the time Laker Airways was battling the authorities on both sides of the Atlantic to gain approval for its revolutionary "Skytrain" low-fare, "no frills" transatlantic scheduled service that it intended to operate between London and New York City on a daily basis.The resulting compromise led to the framing of a set of new "Advance Booking Charter" (ABC) flight rules that did away with all of the onerous rules that had governed "affinity group" charters other than a four-week advance booking period (subsequently reduced to two weeks).However, the subsequent introduction of Laker Airways' "Skytrain" operation on key transatlantic routes between the UK and the US as well as the competitive response this triggered from other airlines, including many long-established IATA members, resulted in a growing range of low fares being offered on most scheduled services on a year-round basis.