It used to be that if you bought a window seat on a plane, your seat would be perfectly lined up with a window. But if you've flown in recent years, you may have noticed your entire row doesn't line up nicely with a window.
"When the airplane was purchased from the manufacturer, the seats matched perfectly with the windows," said Richard Levy, a retired pilot with over 50 years of experience. Levy runs a consulting firm called Aviation Expert Consulting now.
Levy explains that after an airline purchases an airplane, it is free to move the seats around as it wishes. Here are a few reasons why an airline could want to do that:
Fit more or fewer seats
Airlines sometimes move seats so they can fit more passengers on board.
"There could be adding more seats to make more money, put more people back there," Levy said. "It could be adding, changing out the original seats to put more comfortable seats on there."
Adding more seats not only reduces the legroom but also means airlines have to fit more seats in the same space. As a result, some rows of seats may not line up perfectly with a window.
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Access to Wi-Fi
U.S. & World
Adding Wi-Fi connectivity to a plane sometimes requires wiring individual seats with technology to support the signal, said Levy. When an airline does this, the dimensions of the seat may change.
"It's like a domino effect, " Levy said. "It will move up maybe an inch, half an inch, a quarter of an inch. And then eventually somebody is going to lose a little bit of window. But you always have window space."
"Now, if the electronics people, the maintenance people, can attach the Wi-Fi equipment underneath the seat, then you don't have to change the seat."
The same applies to power outlets. Some airlines include power outlets on the backs of their seats, which makes the seats increase in size.
Lavatories
Depending on the type of plane you board and the duration of the flight, you may have noticed that the size of the bathroom varies.
"If it's a short-range type flight, or they make them larger for long-range flying and more comfortable, spacious, that's going to affect the seating also," Levy said.
Are there safety concerns?
While all these factors may affect how much window space you get, the good news is that there are no safety concerns.
"As far as safety, it has zero to do with that," Levy said. "What is important for safety are the emergency exits."
"Neither the airline or the manufacturer can block emergency exits. They have to stay perfectly open."
Levy says airlines measure different factors — profit, comfort and amenities, to name a few — when deciding how many seats to fit on an aircraft.
"The airline's hoping that you are comfortable, that you're happy, and you enjoy at least as much of the view as you can get," Levy said.