The Rolls-Royce Griffith VTO was a bold 1950s British concept blending supersonic speed with vertical takeoff, powered by a staggering 68 jet engines. Designed to carry 44 passengers across the ...

Such a concept scales up the QSST-X to a maximum take-off weight of about 90,700kg (200,000lb), Paulsen says. It would remain capable of a cruise speed of Mach 1.6-1.8.

As Boom Supersonic continues efforts to build the world's fastest airliner, they've revealed a sort of proof-of-concept. The Boom Supersonic XB-1 is a "supersonic demonstrator" aircraft.