Emirates is offering 2-for-1 pricing on tickets to Dubai, recalling American CEO Bob Crandall's 2-for-1 pricing in 1992 that triggered the biggest fare sale in industry history.
American and Delta have both dropped routes to India, leaving United as the only U.S. carrier in the market, where the Gulf carriers have tightened their grip on the market.
Hawaiian Airlines says it will retrofit the 18 Boeing 717 jets, which it operates between the Hawaiian islands, by the end of the year.
Etihad Airways says it will put an Airbus A380 on the Abu Dhabi-JFK route in December, meaning it will offer passengers the chance to fly in 125-square-foot penthouses for $32,000.
American Airlines President Scott Kirby says the airline is adding 10 seats each to 221 Boeing 737-800s, a one-time event that will not be repeated in 2016.
Spirit follows American Airlines to a downgrade resulting from pricing competition as Southwest adds routes at Dallas Love Field.
American Airlines, unlike most competitors, does not hedge fuel, so it benefits more when fuel prices fall and is hurt more when they rise.
The three global U.S. airlines face plenty of opposition as they battle to end massive subsidies to Gulf carriers.
Southwest told the FAA Tuesday that it had neglected to inspect backup rudder control systems in some Boeing 737s, but then it reached a deal to continue flying the aircraft.
Boeing's 787 Dreamliner enables flights on routes that, initially, don't have huge traffic flows -- routes like Shanghai-Boston and Beijing-San Jose on Hainan Airlines.