Why Are Cabin Lights Dimmed During Takeoff and Landing?

If you’ve ever flown on a commercial airplane, you’ve probably noticed that the cabin lights are dimmed right before takeoff and landing. It’s a small detail, but a consistent one.

Some people assume it’s just a way for the crew to get passengers to stop reading or looking at their phones and pay attention to announcements. In reality, the reason has nothing to do with that.

It’s about safety.

Helping Your Eyes Adjust to Darkness​

Chris Cooke, a commercial pilot who has flown numerous long-haul flights, explained to Travel + Leisure that this practice is part of standard safety procedures. The goal is to prepare passengers in case of an emergency evacuation.

“Imagine you’re in a room you don’t know, fully lit and filled with obstacles,” he said. “Then suddenly, the lights go out and you’re told to get out as fast as possible.”

It’s much easier for your eyes to go from dim lighting to darkness than from bright light to complete darkness. When the cabin is already dim, you’ll be able to see better if the lights suddenly go out, which can make a critical difference during an evacuation.

This is also why window shades are typically required to be open during takeoff and landing. Natural light helps improve visibility and allows both passengers and crew to better assess conditions outside the aircraft.

Your Eyes Need Time to Adapt​

The human eye can take anywhere from 10 to 30 minutes to fully adapt to darkness. By dimming the lights ahead of time, airlines give passengers and crew a head start in adjusting to low-light conditions.

This becomes especially important during nighttime flights. In an emergency, those extra minutes of visual adaptation could significantly improve the chances of evacuating safely.

Making Emergency Lighting More Visible​

Another key reason is visibility. When the cabin is darker, emergency exit lights and floor path lighting become much easier to see.

This ensures that, in the event of an evacuation, passengers can quickly locate exits and follow the illuminated pathways without confusion.

According to Colin C. Law, an assistant professor of aviation business at Stamford International University, cabin lighting is carefully adjusted based on outside conditions. For example, during takeoff, the lights are not kept at full brightness because that could interfere with passengers’ ability to see clearly if an evacuation becomes necessary.

Additional Practical Benefits​

Dimming the lights is often combined with opening the window shades. During daytime flights, this allows natural light to fill the cabin, improving overall visibility.

In most cases, of course, emergencies never happen. But aviation safety is built around preparation for worst-case scenarios.

There is also a minor operational benefit: reducing cabin lighting slightly lowers energy consumption, helping optimize aircraft performance during critical phases of flight such as takeoff and landing.

In short, that dim cabin isn’t about comfort or convenience — it’s about making sure everyone on board has the best possible chance to react quickly if something goes wrong.