The double-decker airplane seat is back. Here's what it looks like now

[Ocelot II]

29. I can't imagine that those seats would pass FAA certification, or that

an airline would want them even if they did. Of course airlines want as many passengers as possible, but what's possible is limited by both physics and safety regulations. Assuming an airplane has high enough ceilings to accommodate those seats (most don't), the weight of the additional passengers and the seats themselves would likely cause the airplane to exceed its maximum takeoff weight by a lot. In any event, even if the plane could fly, there's a point where more weight means less revenue because it takes more fuel to carry more weight. Also, there's an FAA rule that says that during an emergency evacuation all passengers have to able to get out in no more than 90 seconds. Those seats, if filled, would cause a horrific clusterfuck if passengers had to be evacuated. And who wants to sit with someone else's ass in their face? Even if you could get a cheap ticket?