I'd imagine such a mechanism would be a decent bit heavier than standard airline recliners (as mentioned in the article, "Today, an economy seat that tips the scales above 9 kilograms (20 pounds) is, by an airline’s measure, too heavy to fly")
Also, if the seats slide downwards, does that impinge on the small luggage space underneath the seat for the person behind?
Re:The Incredible Shrinking Airline Seat
by seszett on Saturday August 19, 2017 @03:42AM
(#15052205)
The seats don't just slide downwards, the seating part slides forward on the frame that is fixed, so in effect the top of the seat gets lower, the angle of the back increases, and the forward edge moves forward. The space under the seat isn't affected.
But yeah, the seats are probably bulkier.
It doesn't seem that complicated, actually at least French trains have solved this by making reclining seats slide down their frame (and forward) instead of actually recline backwards into the rear passenger's space. It works really well, and the result is that reclining uses the reclining person's space and cannot bother anyone else.
However, these trains have more leg space and sturdier seats than regular planes, so maybe it's more difficult to achieve on a plane?