Is it rude to keep the airplane window shades open?

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The great window-shade debate

Airplane question for you: If you're in a window seat, do you keep the shade up or down?

We raised this in our morning news meeting a few days ago, and the room erupted into a fierce debate over flying etiquette. This is up there with whether reclining your seat is appropriate, or society's unwritten rules around airplane armrests or taking off your shoes and socks.

For some travelers, open shades offer a lot of positives. You can watch the clouds, take a photo, or just feel a little less claustrophobic at 35,000 feet. (I'm shades up, for sure!)

For others, leaving the shade open is an act of selfishness. Sunlight pouring into the airplane cabin can keep half the plane awake, or cause glare on laptop or tablet screens. These folks very much want the shades closed. Flyers have been intensely litigating the issue on Reddit in recent days.

So, who's right in the window-seat debate?

The practical answer depends on the moment. Many airlines require the shades to be open during takeoff and landing for safety reasons, so passengers and crew can spot hazards outside and emergency responders can see into the cabin. But once the plane reaches cruising altitude, there are generally few rules governing the shade.

From there, it's all etiquette.

We spoke with a former flight attendant who spent nearly a decade working for an international airline. She has particularly strong feelings about how this debate should be settled.

Where do you stand on the issue? Should airplane window shades be open or shut during flights? Drop me a note at srussolillo@businessinsider.com and let me know what you think.