Why Did Boeing Build The 777X With Folding Wings?

Two of the most notable developments with the upcoming Boeing 777X are its massive General Aerospace GE9X engines and its folding wingtips. While it is usual for aircraft to have unfolding wings, it is far from unprecedented. Navy military aircraft designed to operate from aircraft carriers have had folding wingtips for decades. On aircraft carriers, folding wings help aircraft to make as much use of limited space as possible.