The dissolution of the Delta-Aeromexico joint venture on Jan. 1 isn't likely to have a major impact on consumers or on those carriers' combined transborder route networks, analysts say.
But the protectionist posture projected in Transportation Secretary Sean Duffy's order that ends the Delta-Aeromexico antitrust immunity could portend challenges to come for global aviation.
"The whole airline industry is worrying about that," said John Grant, senior analyst for the airline data tracker OAG.
The Sept. 15 order won't end codesharing between Delta and Aeromexico. And Delta can continue as a 20% Aeromexico owner. But the two carriers will have to stop jointly scheduling and pricing U.S.-Mexico flights. In addition, with the end of the joint venture, revenue sharing across their combined cross-border networks will be replaced by smaller fees or commissions.
During the 20 months that the DOT contemplated shutting down the joint venture, Delta and Aeromexico warned that such a move would jeopardize two dozen routes and could force the airlines to fly existing routes with smaller planes.
When the decision was announced, Delta said it would "cause significant harm to U.S. jobs, communities and consumers traveling between the U.S. and Mexico."
But the airline also said all of its Mexico flights would continue as normal unless customers are contacted and told otherwise.
Aeromexico offered a similar message.
Mexico City-based aviation analyst Fabricio Cojuc said he expects only a few marginal routes to be imperiled. Since the joint venture started in 2016, Delta and Aeromexico have fine-tuned their networks to avoid overlap and to be cooperative, Cojuc said. As a result, during the fourth quarter of this year the two carriers will overlap on just three routes, Mexico City-New York JFK, Mexico City-Salt Lake City and Monterrey-Atlanta.
With the end of the joint venture, Delta, the much larger of the two partners, could theoretically attempt to compete with Aeromexico on some of its U.S. routes. But with Delta owning 20% of Aeromexico, that course of action is unlikely, Cojuc said.
The airlines, of course, will want to adjust schedules and capacity as market conditions change, but multi-airline connections can be synchronized through key hubs like Atlanta and Mexico City even without direct coordination.
"I think these guys know each other inside out, so they will have made contingency plans," Cojuc said. "I think you are going to see predictable, steady, nondramatic changes to the networks. It's a hard pill to swallow, but it's not a poison pill."
Still, he said he expects the airlines to consider dropping routes that don't make economic sense absent the full benefits that come from joint-venture profit sharing. Two that he singled out are Aeromexico's daily regional jet service between Mexico City and Raleigh-Durham, N.C., which started in July 2024, and its daily regional jet flights between San Luis Potosi and Atlanta, which launched in June of this year. On both of those routes, said Cojuc, Aeromexico relies heavily on Delta's ability to market inbound multi-airline itineraries from its vast network.
Similarly, the carriers will be less likely to establish new service on marginal routes, the analyst said.
From Biden to Trump's DOT
It was the Biden administration DOT, led by Pete Buttigieg, that initiated proceedings to end the Delta-Aeromexico antitrust immunity in January 2024, citing the Mexican government's decision to cut hourly flight operations at Mexico City Airport from 61 to 43 in 2022 and 2023, and also to terminate cargo service there in 2023. Mexico City cargo flights instead must now go to the new Felipe Angeles Airport, 28 miles to the north of the main airport. The restrictions, the Biden DOT warned, violated the open market-oriented air transport agreement between the U.S. and Mexico.
The matter, though, ultimately languished until it was picked up by Trump's DOT.
In a Sept. 16 press release, the DOT framed its decision to break up the joint venture as demonstration of Trump's "America first agenda in our skies."
"President Trump and Secretary Duffy are taking note of multiple other countries that are disregarding the terms of our air transport agreements," they noted, before making a veiled reference to the Netherlands, which has reduced flight capacity at Amsterdam Airport to reduce noise pollution -- an action that also garnered attention from the Biden DOT.
OAG's Grant said that concerns about whether Trump's economic protectionism will spill over to air travel were pervasive at the Routes World conference, which he attended late last month in Hong Kong.
"It feels like a piece of market interference that is not necessary," he said of the Delta-Aeromexico breakup.
The U.S. has pushed for open international flight markets since the 1990s and currently has 142 Open Skies agreements in force, the State Department website shows.
"It's ironic," Grant said. "They were the pioneers of Open Skies, and now they are the ones pulling back from that."