Multiple Boeing projects were pursued and then canceled, notably the Sonic Cruiser, a proposed jetliner that would travel just under the speed of sound, cutting intercontinental travel times by as much as 20%.
Beberapa proyek Boeing dikejar dan kemudian dibatalkan, terutama Sonic Cruiser, sebuah pesawat jet usulan yang akan melakukan perjalanan tepat di bawah kecepatan suara, memotong waktu perjalanan antarbenua sebanyak 20 persen.