The report estimates that Southwest would add 98 flights at Love if the master plan is eliminated, or 77 if the plan remains. The airline now has 112 daily flights.
But Southwest has predicted more modest growth. Gary Kelly, the airline's chief executive, has said that if the amendment is repealed, Southwest will initially add about 22 flights and up to 50 over several years.
The study does not mention the amendment's impact on airfares, which for many travelers is central to the debate.
Fares are also the crux of Southwest's argument. Airline officials say fares would drop at both Love and D/FW if the restrictions are lifted, and more people would fly out of both airports.
"We've never gone into a market that didn't grow," Southwest's Stewart said. "That's what would happen at D/FW."
Sbarra said the big question for North Texas consumers is whether lower fares are worth some drawbacks, such as the shifting of flights from D/FW to Love Field or reduced service to some smaller cities.
"That's what people need to consider," he said. "It's a complicated issue."
Study author Cassotis told reporters at an airport briefing Tuesday that fares will likely decrease if the Wright Amendment is eliminated. But she added that new low-fare airlines will likely come to D/FW, lowering fares there, even if the restrictions remain.
"Fares would drop in either case," she said.
Since Delta closed its hub at D/FW this year, D/FW officials haven't had any luck in attracting new low-fare service. The airport has offered $22 million in incentives, but no airlines have signed on.
The only low-cost airline to add flights at D/FW in recent years, AirTran Airways, has faced a fierce battle with American, particularly on routes to Los Angeles.
Airport officials also released a packet of quotations attributed to Herb Kelleher, Southwest's co-founder and chairman, that appear to support the Wright Amendment.
For example, the airport produced a 1979 quote from the Star-Telegram in which Kelleher said he was "personally pleased that the Wright Amendment will finally bring peace to the Dallas/Fort Worth area."
But Southwest spokesman Stewart pointed out that most of the quotes are 15 to 25 years old and claimed that they were taken out of context.
"In no way, shape, form or fashion has Herb ever supported the Wright Amendment," Stewart said.
Southwest's stock (ticker: LUV) dropped 43 cents to close at $14.95 per share. Stock in AMR Corp., American's parent company (AMR), fell 36 cents to close at $11.02 per share.
Consultants say that if the Wright Amendment is repealed:
Dallas/Fort Worth Airport, the world's sixth-busiest airport in terms of passengers, would drop to 16th, based on Airports Council International figures.
D/FW could lose 14 million to 21 million passengers, dropping it to 1985 levels. Traffic would not recover for 19 years.
Fewer passengers and more debt would likely require higher landing fees, raising the costs for airlines and making it harder for D/FW to attract new carriers.
Connecting international passengers would drop up to 24 percent, which would likely mean fewer flights to Latin America.
Flights at Dallas Love Field could triple, resulting in up to 16 million more passengers annually, which would add congestion to surrounding neighborhoods. Pressure to use larger aircraft could render invalid Dallas' master plan, which limits growth at the airport.
SOURCE: Dallas/Fort Worth International Airport: Potential Airport Impacts -- Repeal of Wright Amendment by Simat, Helliesen & Eichner; D/FW Airport