Originally Posted by CPH-Flyer

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The narrower seats are sadly a consequence of buying a smaller aircraft than the 777-300ER, and then trying to get close to the same seat count. Something has to give. The domestic A350 was going from the 777 3-4-3 to A350 3-3-3 so quite the improvement. But in the end, the A350 cabin is just narrower than the 777, and even less roomy than the original design (yet only used by JAL) 2-4-2 of the 787.