Some of the world’s largest aircraft manufacturers seem convinced that adding new technologies and increasing automation will allow airlines to reduce the number of pilots on the flight deck. For them, it is a question of when, not if. Despite the misconception that planes largely fly themselves, they can’t. Autopilot on commercial flights is simply a tool designed to assist pilots, not completely replace their training and experience. As these manufacturers push to advance technology on the flight deck, there is a red line that must not be crossed: any effort that removes pilots from the controls.

As we prepare for a busy holiday travel season, our industry’s paramount commitment to passenger safety must never be in doubt. That’s why it is essential to sound the alarm before a bad idea—like removing pilots from the flight deck—takes root. Unfortunately, this isn’t some far-fetched, far-in-the-future proposition; it’s something airplane manufacturers are actively working to implement as soon as possible. Already, European manufacturers Dassault and Airbus are pursuing designs that introduce new technologies they say would allow a single pilot to actively fly a commercial plane.

Pilots have long embraced technology that makes flying safer by improving their ability to manage and troubleshoot emergency situations and irregular events as a team. But relying on technology, no matter how advanced, to fully assume the role of one or both pilots onboard commercial flights is a step too far. As an airline pilot with 28 years of experience, I can tell you that technology fails, even on the flight deck of a new airliner featuring the latest bells and whistles. Putting increased trust in autonomous systems creates an overreliance on systems that could undoubtedly fail or be hacked.

Recent high-profile events underscore why two rested, highly trained and qualified pilots are essential on every flight. Last year, two pilots working together on board a FedEx Express Boeing 767 identified and averted a potential disaster by acting quickly to avoid colliding with a Southwest Boeing 737 in dense fog over Austin. Similarly, the rapid decompression that occurred on Alaska Airlines Flight 1282 earlier this year after a door plug blew out inflight required two pilots on the flight deck to safely land that plane—an effort National Transportation Safety Board Chair Jennifer Homendy called “heroic”.

In both cases and hundreds of others just like them, it wasn’t technology that averted disaster. It was a team of two pilots working together, combining their shared expertise, awareness and ability to quickly analyze multiple factors to make decisions that led to a safe outcome. While a combination of factors led to these events, this critical safety feature worked exactly as designed. Incredibly, despite stories like this and the countless other in-flight computer or mechanical issues that don’t make headlines, some manufacturers are still forging ahead and seeking to replace pilots with automation. These incidents should remind us that pilots provide the vital—and irreplaceable—ability to identify and react during a wide range of critical moments in flight, a message I helped personally deliver to Airbus CEO Guillaume Faury in a joint letter.

Technology has tremendous potential to decrease workload and enhance awareness while also creating safer flights for passengers. However, the push for automation coupled with fewer—or even zero—human pilots is not about using technology to enhance safety: it’s about increasing profitability. The flying public is overwhelmingly opposed to removing pilots from the flight deck. A survey commissioned by the Air Line Pilots Association, the organization I represent, found nearly 80% of U.S. adults say remotely operated planes would make them feel less safe flying—and a significant majority say they would never feel comfortable flying without two pilots on the flight deck. A separate survey from the International Transport Workers’ Federation also found strong opposition globally to fully autonomous flight, with 76% of respondents saying they would not feel comfortable on a plane without a pilot on board.

As pilots, we owe it to our passengers to warn them when storm clouds roll in and turbulence lies ahead. Attempts to replace pilots invite danger to our skies and add significant risk to the lives of those in the air and on the ground. As we consider the future of air travel, we must not roll the dice with a single pilot at the controls or visions of computers solely operating commercial airliners.

Gambling with safety in such ways is a fool’s bet that neither pilots nor the flying public are willing to make.

Capt. Jason Ambrosi is the 12th president of the Air Line Pilots Association, International, is the world’s largest airline pilot union representing more than 78,000 airline pilots in the United States and Canada.

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