The Labyrinth of Air Navigation in the Valley of Mexico

Season 1, Episode 17 | December 3rd, 2025

Executive Summary (English)

This episode of Altitude delivers an in-depth and unfiltered analysis of the aviation challenges in Mexico City’s Valley airspace, one of the most complex environments in the world. The discussion explains how Mexico moved from a long-term, high-capacity solution (Texcoco) to a dual-airport system (AICM + AIFA) that is intrinsically constrained by geography and design.

Key insights include:

• Texcoco vs. AICM+AIFA: Texcoco offered up to 140 operations per hour with true triple-runway simultaneity; the AICM+AIFA system is limited to ~44 operations due to interfering flight paths and airspace saturation.

• Redesign shortcomings: The 2021 airspace redesign reorganized flows but did not provide operational independence between both airports.

• Capacity cuts: The AICM’s reduction from 61 to 44 operations per hour was driven by the need to “make room” for AIFA within the same constrained airspace—not due to passenger experience improvements.

• U.S. DOT reaction: Capacity cuts and slot reallocations triggered diplomatic friction, with the DOT arguing discrimination against U.S. carriers and imposing restrictions on Mexican airlines.

• Slots conflict: Returning slots to U.S. airlines without increasing total capacity mathematically reduces access for Mexican carriers.

• Long-term reality: Under the current configuration, the AICM+AIFA system will never match Texcoco’s projected capacity, resilience, or hub competitiveness.

• Core recommendation: Mexico must adopt a 30-year, technical—not political— vision for its airport system to meet actual demand.

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INTRO

Nico: Welcome to Altitude. Today we’re diving deep into a topic that affects everyone: what is really happening with air navigation in the Valley of Mexico? The AICM, the AIFA, capacity cuts, slots, U.S. relations, Texcoco… everything.

Fabricio: And today, more than ever, we want to hear from Arturo. We’re going to put him on the spot with tough questions so he can explain—no filters—how we got here and what needs to be done to fix it.

Nico: Let’s get started. Arturo, we begin with you.

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BLOCK 1 – How did we get here?

Fabricio: Arturo, for context: how would you explain the transition from Texcoco to the AICM+AIFA system?

Arturo: If I had to summarize the story in two minutes, I’d say this: Mexico had one major airport—the AICM—which had been operating at its limit for years. Technically it could handle around 61 operations per hour, but in good weather we would push it to 65 or even 70 with a lot of pressure, delays, and no safety margin. It was obvious we had reached the ceiling.

Texcoco was designed as a State-level solution, not a six-year administration project: an airport with three runways that could operate simultaneously, eventually expandable to six, and projected to handle more than 140 operations per hour from day one. It was an infrastructure plan for several decades—a true hub.

Then came the turning point: Texcoco was cancelled, and the country pivoted to Santa Lucía. Instead of one large airport replacing the AICM, we now had two airports sharing an extremely complex airspace. And for AIFA to “fit” inside that airspace, the AICM had to sacrifice capacity. That’s where the current problem begins.

Nico: How different was Texcoco from the current setup?

Arturo: Radically different. Texcoco wasn’t “another airport”—it was an integrated system. It allowed full triple-runway simultaneity, something we cannot do at the AICM. It offered much cleaner airspace, modern navigation systems, and room for growth.

What we have now is a split system: two airports sharing routes, altitudes, and procedures inside a valley surrounded by mountains. It’s like going from a four-lane highway to two parallel avenues full of speed bumps. They work, but you lose flow and capacity.

Fabricio: It has now been seven years since the cancellation of the NAIM project that would have replaced the AICM. What were the government’s arguments? Arturo: The official narrative focused on three points:

1. Corruption and cost overruns

2. Environmental impact on the lakebed area

3. The idea that Santa Lucía was cheaper

But these arguments never aligned with the technical studies. Everything related to capacity, safety, airspace, future connectivity, and operations pointed to Texcoco as the only long-term solution. Its cancellation was a political decision—not a technical one.

BLOCK 2 – The AICM–AIFA coexistence

Nico: Explain why it is so complicated to have two major airports in the Valley of Mexico.

Arturo: The Valley of Mexico is a bowl surrounded by mountains. All aircraft arriving at the AICM must follow very specific corridors with strictly defined altitude profiles and limited maneuverability.

When you add a second major airport into the same space, their routes intersect at critical altitudes: aircraft descending into the AICM meet those climbing or descending into AIFA. It’s like having two highways crossing at different heights but without a traffic light.

In places like London or New York, airports were designed from the start to work together. Here, AIFA was inserted into a system never planned for two major airports.

Fabricio: The airspace redesign was sold as a major integrated solution. What really happened?

Arturo: The redesign promised independence between both airports. The reality is—it didn’t deliver it.

It reorganized routes but didn’t eliminate vertical conflicts. We still rely on sequencing arrivals, stretching vectors, using holding patterns, and at certain times of day, deciding which airport “dominates.”

In plain terms: the redesign rearranged the traffic, but didn’t create more capacity. At times it even added complexity.

Nico: So, is there real simultaneous operation today?

Arturo: There is simultaneity on paper, but not true independence. For two airports to operate fully at the same time, their arrival and departure paths must not interfere. Here, they do. That’s why the AICM had to cut operations—to create space for AIFA. The system works, but with more limitations than before.

BLOCK 3 – Capacity cuts

Fabricio: The AICM went from 61 to 43 operations per hour in just 14 months, and then up slightly to 44. Why?

Arturo: The official explanation talks about improving service, reducing terminal congestion, and enabling construction works. In reality, it was a three-step process:

• First from 61 to 52

• Then from 52 to 43

• Recently up to 44

Why? Because for AIFA to operate, the density at the AICM had to drop. Two airports sharing such a limited airspace cannot run at maximum density simultaneously. The cut was a way to create room in the sky.

Nico: Who is hit hardest?

Arturo: Mexican airlines. They operate most of their flights out of the AICM, and it is their strongest revenue generator. With fewer slots, they lose growth potential, bank structure, and scheduling flexibility. For passengers, this means fewer options, higher load factors, and at times higher fares.

Fabricio: And what happened with U.S. carriers? Why did the DOT file complaints and impose sanctions on Mexican airlines?

Arturo: Because they viewed Mexico as affecting their access to the AICM. If you cut capacity and reassign slots, you must follow the bilateral agreement. The DOT interpreted the process as favoring Mexican airlines and violating the spirit of “open skies.”

Their response was severe: suspending Mexican carrier routes, blocking new operations, and even prohibiting flights to the U.S. from AIFA.

SPECIAL BLOCK – What is a slot?

Nico: Really interesting Arturo, but let’s clarify what a slot is. A slot is a permit to take off or land at a specific time. Think of it as a ticket to use a runway for exactly one minute within a precise sequence.

Example: If a toll booth can only let one car pass every 60–90 seconds and the limit is 44 cars per hour, you cannot push 60 “just because.” Each car needs its turn. That turn is the slot.

Fabricio: And that’s why each slot is so valuable A saturated airport cannot add more flights. The AICM is classified by IATA as one of only 13 Level-3 airports in the Americas. Before, we had 61 slots per hour. Now we have 44. Twenty-eight percent of the “places” no longer exist.

If Aeroméxico, Volaris or Delta need a new flight, they cannot add it if the hour is saturated. They must wait for someone to return a slot or take a less favorable time. And here is the sensitive part: If Mexico returns slots to U.S. airlines without increasing total capacity, Mexican carriers must give up their slots. It’s like losing your place in the fast lane to give it to someone else.

BLOCK 4 – Slot returns to the U.S.

Nico: What does it mean for Mexico to return slots to U.S. carriers without increasing total AICM capacity?

Arturo: It means we’re reallocating a pie that doesn’t grow. If there are 44 operations per hour and that number doesn’t increase, any new slot for a U.S. airline means one less for a Mexican airline. There’s no magic. It’s pure arithmetic. This affects domestic networks, connections, and key frequencies.

Fabricio: Does this decongest the AICM or just kick the can down the road?

Arturo: It doesn’t decongest anything. It only redistributes who flies when. Total operations remain the same—and the airport stays saturated.

BLOCK 5 – The Texcoco scenario

Nico: If Texcoco existed today with its three initial runways, how would things look? Arturo: We’d have around 140 operations per hour instead of 44. We’d have three simultaneous runways instead of two that essentially function as one. We’d have an airport more resilient to fog and adverse weather. We’d have a hub capable of competing regionally. In raw numbers: we would have tripled system capacity.

Fabricio: Could the AICM+AIFA system reach that in the coming years? Arturo: No. Not with the current configuration. The airspace simply doesn’t allow it. Capacity is not unlimited. We can improve processes and optimize routes, but it will never match Texcoco’s design.

CLOSING

Nico: If you could make one decision to fix the airport system of the Valley of Mexico, what would it be?

Arturo: To adopt a 30-year vision—not a six-year one. To be honest about real demand and about the valley’s limitations. And to build infrastructure based on technical reasoning, not politics. If we don’t do that, we will keep patching a system that is already insufficient.

Fabricio: Thank you, Arturo. Very clear and straight to the point.

Nico: Thanks to everyone for joining us. See you in the next episode of Altitude.